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Sample records for spectrometry hplc-icp ms

  1. Application of high performance liquid chromatography with inductively coupled plasma mass spectrometry (HPLC-ICP-MS) for determination of chromium compounds in the air at the workplace.

    Science.gov (United States)

    Stanislawska, Magdalena; Janasik, Beata; Wasowicz, Wojciech

    2013-12-15

    The toxicity and bioavailability of chromium species are highly dependable on the form or species, therefore determination of total chromium is insufficient for a complete toxicological evaluation and risk assessment. An analytical method for determination of soluble and insoluble Cr (III) and Cr (VI) compounds in welding fume at workplace air has been developed. The total chromium (Cr) was determined by using quadruple inductively coupled plasma mass spectrometry (ICP-MS) equipped with a dynamic reaction cell (DRC(®)). Soluble trivalent and hexavalent chromium compounds were determined by high performance liquid chromatography with inductively coupled plasma mass spectrometry (HPLC-ICP-MS). A high-speed, reversed-phase CR C8 column (PerkinElmer, Inc., Shelton, CT, USA) was used for the speciation of soluble Cr (III) and soluble Cr (VI). The separation was accomplished by interaction of the chromium species with the different components of the mobile phase. Cr (III) formed a complex with EDTA, i.e. retained on the column, while Cr (VI) existed in the solutions as dichromate. Alkaline extraction (2% KOH and 3% Na2CO3) and anion exchange column (PRP-X100, PEEK, Hamilton) were used for the separation of the total Cr (VI). The results of the determination of Cr (VI) were confirmed by the analysis of the certified reference material BCR CRM 545 (Cr (VI) in welding dust). The results obtained for the certified material (40.2±0.6 g kg(-1)) and the values recorded in the examined samples (40.7±0.6 g kg(-1)) were highly consistent. This analytical method was applied for the determination of chromium in the samples in the workplace air collected onto glass (Whatman, Ø 37 mm) and membrane filters (Sartorius, 0.8 μm, Ø 37 mm). High performance liquid chromatography with inductively coupled plasma mass spectrometry is a remarkably powerful and versatile technique for determination of chromium species in welding fume at workplace air. Crown Copyright © 2013 Published by

  2. Measurement of isotopic composition of lanthanides in reprocessing process solutions by high-performance liquid chromatography with inductively coupled plasma mass spectrometry (HPLC/ICP-MS)

    International Nuclear Information System (INIS)

    Okano, Masanori; Jitsukata, Shu; Kuno, Takehiko; Yamada, Keiji

    2011-01-01

    Isotopic compositions of fission products in process solutions and wastes in a reprocessing plant are valuable to proceed safety study of the solutions and research/development concerning treatment/disposal of the wastes. The amount of neodymium-148 is a reliable indication to evaluate irradiation history. The isotopic compositions of samarium and gadolinium in high radioactive wastes are referred to as essential data to evaluate environmental impact in geological repositories. However, pretreatment of analysis must be done with complicated chemical separation such as solvent extraction and ion exchange. The actual measurement data of isotopic compositions of lanthanides comparable to the one of actinides in spent fuel reprocessing process has not been obtained enough. Rapid and high sensitive analytical technique based on high-performance liquid chromatography (HPLC) with an inductively coupled plasma mass spectrometry (ICP-MS) has been developed for the measurement of isotopic compositions of lanthanides in spent fuel reprocessing solutions. HPLC/ICP-MS measurement system was customized for a glove-box to be applied to the radioactive solutions. The cation exchange chromatographic columns (Shim-pack IC-C1) and injection valve (20μL) were located inside of the glove-box except the chromatographic pump. The elements of lanthanide group were separated by a gradient program of HPLC with α-hydroxyisobutyric acid. Isotopic compositions of lanthanides in eluate was sequentially analyzed by a quadruple ICP-MS. Optimization of parameter of HPLC and ICP-MS measurement system was examined with standard solutions containing 14 lanthanide elements. The elements of lanthanides were separated by HPLC and detected by ICP-MS within 25 minutes. The detection limits of Nd-146, Sm-147 and Gd-157 were 0.37 μg L -1 , 0.69 μg L -1 and 0.47 μg L -1 , respectively. The analytical precision of the above three isotopes was better than 10% for standard solutions of 100 μg L -1 with

  3. Multielemental speciation analysis by advanced hyphenated technique - HPLC/ICP-MS: A review.

    Science.gov (United States)

    Marcinkowska, Monika; Barałkiewicz, Danuta

    2016-12-01

    Speciation analysis has become an invaluable tool in human health risk assessment, environmental monitoring or food quality control. Another step is to develop reliable multielemental speciation methodologies, to reduce costs, waste and time needed for the analysis. Separation and detection of species of several elements in a single analytical run can be accomplished by high performance liquid chromatography hyphenated to inductively coupled plasma mass spectrometry (HPLC/ICP-MS). Our review assembles articles concerning multielemental speciation determination of: As, Se, Cr, Sb, I, Br, Pb, Hg, V, Mo, Te, Tl, Cd and W in environmental, biological, food and clinical samples analyzed with HPLC/ICP-MS. It addresses the procedures in terms of following issues: sample collection and pretreatment, selection of optimal conditions for elements species separation by HPLC and determination using ICP-MS as well as metrological approach. The presented work is the first review article concerning multielemental speciation analysis by advanced hyphenated technique HPLC/ICP-MS. Copyright © 2016 Elsevier B.V. All rights reserved.

  4. Determination of the total drug-related chlorine and bromine contents in human blood plasma using high performance liquid chromatography-tandem ICP-mass spectrometry (HPLC-ICP-MS/MS).

    Science.gov (United States)

    Klencsár, Balázs; Bolea-Fernandez, Eduardo; Flórez, María R; Balcaen, Lieve; Cuyckens, Filip; Lynen, Frederic; Vanhaecke, Frank

    2016-05-30

    A fast, accurate and precise method for the separation and determination of the total contents of drug-related Cl and Br in human blood plasma, based on high performance liquid chromatography - inductively coupled plasma - tandem mass spectrometry (HPLC-ICP-MS/MS), has been developed. The novel approach was proved to be a suitable alternative to the presently used standard methodology (i.e. based on a radiolabelled version of the drug molecule and radiodetection), while eliminating the disadvantages of the latter. Interference-free determination of (35)Cl has been accomplished via ICP-MS/MS using H2 as reaction gas and monitoring the (35)ClH2(+) reaction product at mass-to-charge ratio of 37. Br could be measured "on mass" at a mass-to-charge of 79. HPLC was relied on for the separation of the drug-related entities from the substantial amount of inorganic Cl. The method developed was found to be sufficiently precise (repeatability 0.990) from the limit of quantification (0.05 and 0.01 mg/L for Cl and Br in blood plasma, respectively) to at least 5 and 1mg/L for Cl and Br, respectively. Quantification via either external or internal standard calibration provides reliable results for both elements. As a proof-of-concept, human blood plasma samples from a clinical study involving a newly developed Cl- and Br-containing active pharmaceutical ingredient were analysed and the total drug exposure was successfully described. Cross-validation was achieved by comparing the results obtained on Cl- and on Br-basis. Copyright © 2016 Elsevier B.V. All rights reserved.

  5. Metabolite profiling with HPLC-ICP-MS as a tool for in vivo characterization of imaging probes.

    Science.gov (United States)

    Boros, Eszter; Pinkhasov, Omar R; Caravan, Peter

    2018-01-01

    Current analytical methods for characterizing pharmacokinetic and metabolic properties of positron emission tomography (PET) and single photon emission computed tomography (SPECT) probes are limited. Alternative methods to study tracer metabolism are needed. The study objective was to assess the potential of high performance liquid chromatography - inductively coupled plasma - mass spectrometry (HPLC-ICP-MS) for quantification of molecular probe metabolism and pharmacokinetics using stable isotopes. Two known peptide-DOTA conjugates were chelated with nat Ga and nat In. Limit of detection of HPLC-ICP-MS for 69 Ga and 115 In was determined. Rats were administered 50-150 nmol of Ga- and/or In-labeled probes, blood was serially sampled, and plasma analyzed by HPLC-ICP-MS using both reverse phase and size exclusion chromatography. The limits of detection were 0.16 pmol for 115 In and 0.53 pmol for 69 Ga. Metabolites as low as 0.001 %ID/g could be detected and transchelation products identified. Simultaneous administration of Ga- and In-labeled probes allowed the determination of pharmacokinetics and metabolism of both probes in a single animal. HPLC-ICP-MS is a robust, sensitive and radiation-free technique to characterize the pharmacokinetics and metabolism of imaging probes.

  6. Comparison of standard and reaction cell inductively coupled plasma mass spectrometry in the determination of chromium and selenium species by HPLC-ICP-MS

    International Nuclear Information System (INIS)

    Bednar, A.J.; Kirgan, R.A.; Jones, W.T.

    2009-01-01

    Elemental speciation is becoming a common analytical procedure for geochemical investigations. The various redox species of environmentally relevant metals can have vastly different biogeochemical properties, including sorption, solubility, bioavailability, and toxicity. The use of high performance liquid chromatography (HPLC) coupled to elemental specific detectors, such as inductively coupled plasma mass spectrometry (ICP-MS), has become one of the most important speciation methods employed. This is due to the separation versatility of HPLC and the sensitive and selective detection capabilities of ICP-MS. The current study compares standard mode ICP-MS to recently developed reaction cell (RC) ICP-MS, which has the ability to remove or reduce many common polyatomic interferences that can limit the ability of ICP-MS to quantitate certain analytes in complex matrices. Determination of chromium and selenium redox species is achieved using ion-exchange chromatography with elemental detection by standard and RC-ICP-MS, using various chromium and selenium isotopes. In this study, method performance and detection limits for the various permutations of the method (isotope monitored or ICP-MS detection mode) were found to be comparable and generally less than 1 μg L -1 . The method was tested on synthetic laboratory samples, surface water, groundwater, and municipal tap water matrices

  7. HPLC-ICP-MS speciation analysis of arsenic in urine of Japanese subjects without occupational exposure.

    Science.gov (United States)

    Hata, Akihisa; Endo, Yoko; Nakajima, Yoshiaki; Ikebe, Maiko; Ogawa, Masanori; Fujitani, Noboru; Endo, Ginji

    2007-05-01

    The toxicity and carcinogenicity of arsenic depend on its species. Individuals living in Japan consume much seafood that contains high levels of organoarsenics. Speciation analysis of urinary arsenic is required to clarify the health risks of arsenic intake. There has been no report of urinary arsenic analysis in Japan using high performance liquid chromatography with inductively coupled plasma mass spectrometry (HPLC-ICP-MS). We performed speciation analysis of urinary arsenic for 210 Japanese male subjects without occupational exposure using HPLC-ICP-MS. The median values of urinary arsenics were as follows: sodium arsenite (AsIII), 3.5; sodium arsenate (AsV), 0.1; monomethylarsonic acid (MMA), 3.1; dimethylarsinic acid (DMA), 42.6; arsenobetaine (AsBe), 61.3; arsenocholine, trimethylarsine oxide, and unidentified arsenics (others), 5.2; and total arsenic (total As), 141.3 microgAs/l. The median creatinine-adjusted values were as follows: AsIII, 3.0; AsV, 0.1; MMA, 2.6; DMA, 35.9; AsBe, 52.1; others 3.5; and total As, 114.9 microgAs/g creatinine. Our findings indicate that DMA and AsBe levels in Japan are much higher than those found in Italian and American studies. It appears that the high levels of DMA and AsBe observed in Japan may be due in part to seafood intake. ACGIH and DFG set the BEI and BAT values for occupational arsenic exposure as 35 microgAs/l and 50 microgAs/l, respectively, using the sum of inorganic arsenic (iAs), MMA, and DMA. In the general Japanese population, the sums of these were above 50 microgAs/l in 115 (55%) samples. We therefore recommend excluding DMA concentration in monitoring of iAs exposure.

  8. High-performance liquid chromatography and inductively coupled plasma mass spectrometry (HPLC-ICP-MS) for the analysis of xenobiotic metabolites in rat urine: application to the metabolites of 4-bromoaniline.

    Science.gov (United States)

    Nicholson, J K; Lindon, J C; Scarfe, G; Wilson, I D; Abou-Shakra, F; Castro-Perez, J; Eaton, A; Preece, S

    2000-02-01

    The use of HPLC-ICP-MS for the profiling and quantification of the metabolites of 4-bromoaniline following reversed-phase gradient chromatography is demonstrated. In the 0-8 h post dose sample, which contained the highest concentrations of compound-related material, it was possible to detect at least 16 metabolites of the compound. The methodology described offers the possibility of obtaining metabolite profiles and quantification for drugs and other xenobiotics in biological fluids and excreta without the requirement for radiolabelled tracers.

  9. Simultaneous speciation of endogenous and exogenous elements by HPLC/ICP-MS with enriched stable isotopes

    International Nuclear Information System (INIS)

    Suzuki, K.T.

    1996-01-01

    High performance liquid chromatography (HPLC)/inductively coupled argon plasma-mass spectrometry (ICP-MS) was introduced to investigate the distributions of selenium (Se) in biological fluids. The method was to determine both the natural abundance of Se and an enriched stable isotope of Se used as a tracer. The distributions of Se in plasma and in urine specimens were determined in Wistar rats on various Se diets with and without an intravenous injection of 82 Se-selenite. Although the distribution of natural abundance Se (endogenous Se) in the plasma was affected little by the nutritional status of Se, that in the urine gave a Se peak depending on the nutritional status of Se, and the peak was identified as methylselenol. When 82 Se-selenite was injected in excess into rats given three different Se diets (Se-deficient, Se-adequate, Se-excessive), three Se peaks occurred in the HPLC chromatogram of the urine samples, corresponding to selenite, methylselenol and trimethylselenonium ion in the order of elution, and the intensities of the tracer peaks reflected the nutritional status. These results indicate that the HPLC/ICP-MS method is a powerful analytical tool for specifying Se-containing biological constituents, both natural abundance and enriched stable isotopes. Methylselenol in urine is proposed to be a sensitive and Se-specific biological indicator for diagnosing the nutritional status of Se. Furthermore, it was shown that an enriched stable isotope such as 82 Se-selenite was shown to be used for the same purpose, and that 82 Se-methylselenol and 82 Se-trimethylselenonium ion in urine were more sensitive indicators of the Se status of the rats. (author)

  10. [Analysis of Arsenic Compounds in Blood and Urine by HPLC-ICP-MS].

    Science.gov (United States)

    Lin, L; Zhang, S J; Xu, W C; Luo, R X; Ma, D; Shen, M

    2018-02-01

    To establish an analysis method for the detection of 6 arsenic compounds [AsC, AsB, As(Ⅲ), DMA, MMA and As(V)] in blood and urine by high-performance liquid chromatography-inductively coupled plasma-mass spectrometryHPLC-ICP-MS), and apply it to real cases. Triton was used to damage cells, and then EDTA·2Na·2H2O was used to complex arsenic compounds in cells, and sonication and protein deposition by acetonitrile were performed for sample pretreatment. With the mobile phase consisted of ammonium carbonate and ultrapure water, gradient elution was performed for obtaining the arsenic compounds in samples, which were analysed by ICP-MS with Hamilton PRP-X100 column. The limits of detection in blood were 1.66-10 ng/mL, while the lower limits of quantitation in blood ranged from 5 to 30 ng/mL. The limits of detection in urine were 0.5-10 ng/mL, while the lower limits of quantitation in urine were 5-30 ng/mL. The relative standard deviation of inter-day and intra-day precisions was less than 10%. This method had been successfully applied to 3 cases. This study has established an analysis method for detecting 6 common arsenic compounds in blood and urine, which can be used to detect the arsenic compounds in the blood and urine from arsenic poisoning cases as well as the patients under arsenic treatment. Copyright© by the Editorial Department of Journal of Forensic Medicine.

  11. HPLC-ICP-MS compared with radiochemical detection for metabolite profiling of H-3-bromohexine in rat urine and faeces

    DEFF Research Database (Denmark)

    Jensen, B.P.; Gammelgaard, B.; Hansen, S.H.

    2005-01-01

    H-3-Bromohexine was dosed to rats as a model compound to allow comparison of HPLC-ICP-MS detection on bromine to radiochemical detection in an in vivo drug metabolism study. Metabolite profiles were obtained in urine and faeces extracts. No influence of the methanol gradient on the bromine response...... was observed in the range of 18 - 75% methanol. The sensitivity obtained by HPLC- ICP-MS was almost two orders of magnitude better than on-line H-3 radiochemical detection. For ICP- MS, the limit of detection was calculated to be 69 nM Br ( injection volume 100 mu l), corresponding to an absolute limit...

  12. Development and application of a method for Cr(III) determination in dairy products by HPLC-ICP-MS.

    Science.gov (United States)

    Hernandez, Fanny; Jitaru, Petru; Cormant, Florence; Noël, Laurent; Guérin, Thierry

    2018-02-01

    This study describes the development of an analytical approach for the determination of Cr(III) in dairy products by microwave assisted extraction, complexation in situ by ethylenediaminetetraacetate (EDTA) and high performance liquid chromatography hyphenated to inductively coupled plasma-mass spectrometry (HPLC-ICP-MS). The extraction step was optimised by using an experimental design. A limit of quantification of 38µgkg -1 dry weight (d.w.) was obtained whereas the bias (%) measured ranged from 10 to 18%. The repeatability and intermediate precision varied between 1.2-5.0% and 7.5-13.5%, respectively. The method was applied to the analysis of several dairy samples beforehand characterized in terms of Cr(VI) and total chromium (Cr total ). Cr(III) concentrations ranged from <13 to 255µgkg -1 d.w. The results showed a good agreement between Cr(III) and Cr total concentration levels. Copyright © 2017 Elsevier Ltd. All rights reserved.

  13. Determination of inorganic arsenic in white fish using microwave-assisted alkaline alcoholic sample dissolution and HPLC-ICP-MS

    DEFF Research Database (Denmark)

    Larsen, Erik Huusfeldt; Engman, Joakim; Sloth, Jens Jørgen

    2005-01-01

    An analytical method for the determination of inorganic arsenic in fish samples using HPLC-ICP-MS has been developed. The fresh homogenised sample was subjected to microwave-assisted dissolution by sodium hydroxide in ethanol, which dissolved the sample and quantitatively oxidised arsenite (As...

  14. Reversed Phase Column HPLC-ICP-MS Conditions for Arsenic Speciation Analysis of Rice Flour.

    Science.gov (United States)

    Narukawa, Tomohiro; Matsumoto, Eri; Nishimura, Tsutomu; Hioki, Akiharu

    2015-01-01

    New measurement conditions for arsenic speciation analysis of rice flour were developed using HPLC-ICP-MS equipped with a reversed phase ODS column. Eight arsenic species, namely, arsenite [As(III)], arsenate [As(V)], monomethylarsonic acid (MMAA), dimethylarsinic acid (DMAA), trimethylarsine oxide (TMAO), tetramethylarsonium (TeMA), arsenobetaine (AsB) and arsenocholine (AsC), were separated and determined under the proposed conditions. In particular, As(III) and MMAA and DMAA and AsB were completely separated using a newly proposed eluent containing ammonium dihydrogen phosphate. Importantly, the sensitivity changes, in particular those of As(V) and As(III) caused by coexisting elements and by complex matrix composition, which had been problematical in previously reported methods, were eliminated. The new eluent can be applied to C8, C18 and C30 ODS columns with the same effectiveness and with excellent repeatability. The proposed analytical method was successfully applied to extracts of rice flour certified reference materials.

  15. Extraction techniques for arsenic species in rice flour and their speciation by HPLC-ICP-MS.

    Science.gov (United States)

    Narukawa, Tomohiro; Suzuki, Toshihiro; Inagaki, Kazumi; Hioki, Akiharu

    2014-12-01

    The extraction of arsenic (As) species present in rice flour samples was investigated using different extracting solvents, and the concentration of each species was determined by HPLC-ICP-MS after heat-assisted extraction. The extraction efficiencies for total arsenic species and especially for arsenite [As(III)] and arsenate [As(V)] were investigated. As(III), As(V) and dimethylarsinic acid (DMAA) were found in the samples, and the concentration of DMAA did not vary with treatment conditions. However, the concentrations of extracted total arsenic and those of As(III) and As(V) depended on the extracting solvents. When an extracting solvent was highly acidic, the concentrations of extracted total arsenic were in good agreement with the total arsenic concentration determined by ICP-MS after microwave-assisted digestion, though a part of the As(V) was reduced to As(III) during the highly acidic extraction process. Extraction under neutral conditions increased the extracted As(V), but extracted total arsenic was decreased because a part of the As(III) could not be extracted. Optimum conditions for the extraction of As(III) and As(V) from rice flour samples are discussed to allow the accurate determinations of As(III), As(V) and DMAA in the rice flour samples. Heat block extraction techniques using 0.05 mol L(-1) HClO4 and silver-containing 0.15 mol L(-1) HNO3 were also developed. Copyright © 2014 Elsevier B.V. All rights reserved.

  16. Speciation analysis of antimony in extracts of size-classified volcanic ash by HPLC-ICP-MS.

    Science.gov (United States)

    Miravet, R; López-Sánchez, J F; Rubio, R; Smichowski, P; Polla, G

    2007-03-01

    Although there is concern about the presence of toxic elements and their species in environmental matrices, for example water, sediment, and soil, speciation analysis of volcanic ash has received little attention. Antimony, in particular, an emerging element of environmental concern, has been less studied than other potentially toxic trace elements. In this context, a study was undertaken to assess the presence of inorganic Sb species in ash emitted from the Copahue volcano (Argentina). Antimony species were extracted from size-classified volcanic ash (<36 microm, 35-45 microm, 45-150 microm, and 150-300 microm) by use of 1 mol L(-1) citrate buffer at pH 5. Antimony(III) and (V) in the extracts were separated and quantified by high-performance liquid chromatography combined on-line with inductively coupled plasma mass spectrometry (HPLC-ICP-MS). Antimony species concentrations (microg g(-1)) in the four fractions varied from 0.14 to 0.67 for Sb(III) and from 0.02 to 0.03 for Sb(V). The results reveal, for the first time, the occurrence of both inorganic Sb species in the extractable portion of volcanic ash. Sb(III) was always the predominant species.

  17. Arsenic speciation in biological environmental samples of aquatic ecosystems by using HPLC-ICP-MS; Speciation von Arsen in biologischen Umweltproben aus aquatischen Oekosystemen mittels HPLC-ICP-MS

    Energy Technology Data Exchange (ETDEWEB)

    Falk, K.

    1999-09-01

    The physicochemical forms of arsenic (arsenic species) which are present in the environment vary significantly with respect to toxicity, bioavailability, stability and transport behaviour. Therefore, it is necessary for an assessment of the toxic potential to humans and the environment to investigate not only the total arsenic concentrations but also to differentiate the single species. By that the knowledge about ecological correlations and pathways will be increased. The present thesis reports the results of a Ph.D. study on the development and optimisation of analytical methods for arsenic speciation and their application to biological samples from different aquatic ecosystems in Germany. The method development included separation of 12 naturally occurring arsenic species by high-performance liquid chromatography (HPLC) followed by an arsenic selective detection by inductively coupled plasma-mass spectrometry (ICP-MS). The arsenic species As (III), As (V), monomethylarsonic acid (MMA), dimethylarsinic acid (DMA), arsenobetaine (AB), arsenocholine (AC), trimethylarsine oxid (TMAO) and tetramethylarsonium (Tetra) were separated with ion-exchange chromatography, whereas reversed-phase chromatography was used for the separation of four arsenosugars. Because of the partly low arsenic concentration in biological samples a very good detection power was required. Therefore, an HPLC-ICP-MS system was tested with different nebulizers. Using the high efficiency nebulizer HHPN (Hydraulic High Pressure Nebulizer), detection limits in the low pg-range could be achieved. The developed analytical methods were applied to arsenic speciation in four marine matrices, which are representative of different trophic levels in the food chain. All samples originated from an ecosystem in the North Sea.

  18. Determination of arsenenic compounds in environmental and biological samples with LAMMA and HPLC-ICP-MS

    International Nuclear Information System (INIS)

    Goessler, W.

    1997-07-01

    Different arsonium salts and alkyl- or aryl arsine sulfides were analyzed with a Laser-Microprobe-Mass-Analyzer (LAMMA-500). The positive-ion spectra of the arsonium salts showed clear signals for the (CH 3 ) 3 AsR + fragment. In the positive-ion spectra of alkyl- or arylarsine sulfides these arsenic compounds the molecular ions R 3 AsS + were never observed, but in most of the spectra the protonated parent compounds R 3 AsSH2 + were present. The negative-ion spectra showed mainly fragments S-n (n = 1, 2, 3, 4) and AsS n (n = 1, 2, 3). Chlorella vulgaris Beijerinck var. vulgaris with a concentration of 13,000 mg As/kg dry mass were analyzed with the LAMMA-500 to identify arsenic compounds. Surprisingly, arsenic could not be detected by the LAMMA technique at these high arsenic concentrations. Electron microscopy of Chlorella cells reveals, that particles adhered at the surface of the cells. Scanning transmission electron microscopy showed a high correlation between the arsenic concentration and the iron concentration in these particles. Algae may protect themselves from high arsenic concentrations, by precipitating FeAsO 4 at the cell surface. Different Chlorella sp. were grown to investigate the arsenic tolerance of Chlorella strains. Chlorella Boehm and Chlorella Kessleri grew better in arsenic-containing than in arsenic-free media. The growth of Chlorella 108 was depressed in high-arsenic media. After harvesting, the algal biomass was extracted and arsenic compounds determined in the extracts with HPLC-ICP-MS. Approximately 98 % of the total arsenic were present as arsenic acid. A method for the simultaneous identification and quantification of arsenocholine, arsenous acid, dimethylarsinic acid, arsenobetaine, methylarsonic acid, and arsenic acid at concentrations below 1 μg/L was developed. The developed HPLC-MPN-ICP-MS system allows the determination of arsenic compounds in urine sample at concentrations of 0.5 μg As/L with a relative standard deviation of

  19. Possible interferences of mercury sulfur compounds with ethylated and methylated mercury species using HPLC-ICP-MS

    International Nuclear Information System (INIS)

    Wilken, R.D.; Nitschke, F.; Falter, R.

    2003-01-01

    The HPLC-ICP-MS coupling technique is able to separate and detect methyl, ethyl and inorganic mercury isotopes specifically. An identification of ethyl mercury(+) is not possible when the widely used sodium tetraethylborate derivatisation method in combination with GC-AFS/AAS or ICP-MS techniques is performed because it contains ethyl groups. An unidentified compound with the same retention time as ethyl mercury was found in the HPLC chromatograms of industrial sewage samples and humic-rich soils of microcosm experiments after applying water vapour distillation. We also observed such unidentified peaks in samples of heavily contaminated sites in Eastern Germany, separated by HPLC fractionation only. In the experiments described, different mercury sulfur adducts were synthesised and tested for their retention times in the HPLC-ICP-MS system. It was found that the compound CH 3 -S-Hg + showed the same retention time as the ethyl mercury standard. It is therefore possible that ethyl mercury detected in chromatography by comparison of the retention time could also be due to an adduct of a sulfur compound and a mercury species. CH 3 -S-Hg + should be tested in other chromatographic mercury speciation methods for this effect. This work can also be regarded as a contribution to the discussion of artificially occurring methyl mercury in sediments during sample preparation. (orig.)

  20. Selenium speciation analysis of Misgurnus anguillicaudatus selenoprotein by HPLC-ICP-MS and HPLC-ESI-MS/MS

    Science.gov (United States)

    Analytical methods for selenium (Se) speciation were developed using high performance liquid chromatography (HPLC) coupled to either inductively coupled plasma mass spectrometry (ICP-MS) or electrospray ionization tandem mass spectrometry (ESI-MS/MS). Separations of selenomethionine (Se-Met) and sel...

  1. Study of HPLC/ICP-MS coupling for the As speciation; Estudo de um acoplamento de HPLC/ICP-MS para a especiacao do As

    Energy Technology Data Exchange (ETDEWEB)

    Cortez, Bruna C.G.; Oliveira, Arno Heeren de [Minas Gerais Univ., Belo Horizonte, MG (Brazil). Dept. de Engenharia Nuclear]. E-mail: brunacortez2004@yahoo.com.br; heeren@nuclear.ufmg.br

    2005-07-01

    Trace metals in the environment may provide benefit or risk to humans, other life forms, and the environment. More robust and information-rich trace and ultra-trace analyses are needed to all adequate risk/benefit assessments. Further, it is no longer adequate to consider only the total trace metal or metalloid, because the impact of elements on ecological systems or biological organisms is not necessarily given by total element concentrations alone. It is necessary to determine the chemical form (species) of the element, primarily the oxidation state or the organometallic nature, because different species of the same metal can range from essential to innocuous to toxic. The actual toxicity levels from different arsenic compounds vary greatly. Inorganic arsenic is considered the most acutely toxic form; arsenite (As{sup III}) is more toxic than arsenate (As{sup V}). The chronic toxicity of arsenic compounds is currently not well understood and is actively being researched. In this study, the viability of the ICP-MS detector coupled with High Performance Liquid Chromatography (HPLC) was tested in 21 water samples from the Das Velhas River, Minas Gerais state, in Brazil. The results showed that the low detection limits and the ease coupling HPLC system - which offers a rugged and versatile separation technique - makes ICP-MS a successful detection method for arsenic speciation analysis. (author)

  2. Simultaneous determination of arsenic, selenium and antimony species using HPLC/ICP-MS

    Energy Technology Data Exchange (ETDEWEB)

    Lindemann, T.; Prange, A.; Neidhart, B. [GKSS-Forschungszentrum Geesthacht GmbH (Germany). Inst. fuer Physikalische und Chemische Analytik; Dannecker, W. [Univ. of Hamburg (Germany). Inst. for Inorganic and Applied Chemistry

    1999-07-01

    A new method for the simultaneous separation and determination of four arsenic species [As(III), As(V), monomethylarsonic acid and dimethylarsinic acid], three selenium species [Se(IV), Se(VI) and selenomethionine] as well as Sb(III) and Sb(V) is presented. The speciation was achieved by on-line coupling of anion exchange high-performance liquid chromatography (HPLC) with inductively coupled plasma mass spectrometry (ICP-MS). Chromatographic parameters such as the composition and pH of the mobile phase were optimised. Limits of detection are below 4.5 {mu}g L{sup -1} (as element) for Sb(III) and the selenium species and below 0.5 {mu}g L{sup -1} for the other species. Precisions of retention times were better than 2% RSD and of peak areas better than 8% RSD for all the species investigated. (orig.) With 5 figs., 3 tabs., 41 refs.

  3. Evaluation of the inorganic selenium biotransformation in selenium-enriched yogurt by HPLC-ICP-MS.

    Science.gov (United States)

    Alzate, Adriana; Cañas, Benito; Pérez-Munguía, Sandra; Hernández-Mendoza, Hector; Pérez-Conde, Concepción; Gutiérrez, Ana Maria; Cámara, Carmen

    2007-11-28

    Selenium is an essential element in the human diet. Interestingly, there has been an increased consumption of dietary supplements containing this element in the form of either inorganic or organic compounds. The effect of using selenium as a dietary supplement in yogurt has been evaluated. For this purpose, different concentrations of inorganic Se (ranging from 0.2 to 5000 microg g(-1)) have been added to milk before the fermentation process. Biotransformation of inorganic Se into organic species has been carefully evaluated by ion-exchange, reversed-phase, or size-exclusion chromatography, coupled to inductively coupled plasma mass spectrometry (ICP-MS). Yogurt fermentation in the presence of up to 2 microg g(-1) of Se(IV) produces a complete incorporation of this element into proteins as has been demonstrated applying a dialysis procedure. Analysis by SEC-ICP-MS showed that most of them have a molecular mass in the range of 30-70 kDa. Species determination after enzymatic hydrolysis has allowed the identification of Se-cystine using two different chromatographic systems. The biotransformation process that takes place during yogurt fermentation is very attractive because yogurt can act as a source of selenium supplementation.

  4. Analysis of gold(I/III)-complexes by HPLC-ICP-MS demonstrates gold(III) stability in surface waters.

    Science.gov (United States)

    Ta, Christine; Reith, Frank; Brugger, Joël; Pring, Allan; Lenehan, Claire E

    2014-05-20

    Understanding the form in which gold is transported in surface- and groundwaters underpins our understanding of gold dispersion and (bio)geochemical cycling. Yet, to date, there are no direct techniques capable of identifying the oxidation state and complexation of gold in natural waters. We present a reversed phase ion-pairing HPLC-ICP-MS method for the separation and determination of aqueous gold(III)-chloro-hydroxyl, gold(III)-bromo-hydroxyl, gold(I)-thiosulfate, and gold(I)-cyanide complexes. Detection limits for the gold species range from 0.05 to 0.30 μg L(-1). The [Au(CN)2](-) gold cyanide complex was detected in five of six waters from tailings and adjacent monitoring bores of working gold mines. Contrary to thermodynamic predictions, evidence was obtained for the existence of Au(III)-complexes in circumneutral, hypersaline waters of a natural lake overlying a gold deposit in Western Australia. This first direct evidence for the existence and stability of Au(III)-complexes in natural surface waters suggests that Au(III)-complexes may be important for the transport and biogeochemical cycling of gold in surface environments. Overall, these results show that near-μg L(-1) enrichments of Au in environmental waters result from metastable ligands (e.g., CN(-)) as well as kinetically controlled redox processes leading to the stability of highly soluble Au(III)-complexes.

  5. Application of ICP-MS and HPLC-ICP-MS for diagnosis and therapy of a severe intoxication with hexavalent chromium and inorganic arsenic.

    Science.gov (United States)

    Heitland, Peter; Blohm, Martin; Breuer, Christian; Brinkert, Florian; Achilles, Eike Gert; Pukite, Ieva; Köster, Helmut Dietrich

    2017-05-01

    ICP-MS and HPLC-ICP-MS were applied for diagnosis and therapeutic monitoring in a severe intoxication with a liquid containing hexavalent chromium (Cr(VI)) and inorganic arsenic (iAs). In this rare case a liver transplantation of was considered as the only chance of survival. We developed and applied methods for the determination of Cr(VI) in erythrocytes and total chromium (Cr) and arsenic (As) in blood, plasma, urine and liver tissue by ICP-MS. Exposure to iAs was diagnosed by determination of iAs species and their metabolites in urine by anion exchange HPLC-ICP-MS. Three days after ingestion of the liquid the total Cr concentrations were 2180 and 1070μg/L in whole blood and plasma, respectively, and 4540μg/L Cr(VI) in erythrocytes. The arsenic concentration in blood was 206μg/L. The urinary As species concentrations were <0.5, 109, 115, 154 and 126μg/L for arsenobetaine, As(III), As(V), methylarsonate (V) and dimethylarsinate (V), respectively. Total Cr and As concentrations in the explanted liver were 11.7 and 0.9mg/kg, respectively. Further analytical results of this case study are tabulated and provide valuable data for physicians and toxicologists. Copyright © 2017. Published by Elsevier GmbH.

  6. Simultaneous Speciation of Arsenic, Selenium, and Chromium by HPLC-ICP-MS

    Science.gov (United States)

    Wolf, Ruth E.; Morman, Suzette A.; Morrison, Jean M.; Lamothe, Paul J.

    2008-01-01

    An adaptation of an analytical method developed for chromium speciation has been utilized for the simultaneous determination of As(III), As(V), Se(IV), Se(VI), Cr(III), and Cr(VI) species using high performance liquid chromatography (HPLC) separation with ICP-MS detection. Reduction of interferences for the determination of As, Se, and Cr by ICP-MS is a major consideration for this method. Toward this end, a Dynamic Reaction Cell (DRC) ICP-MS system was used to detect the species eluted from the chromatographic column. A variety of reaction cell gases and conditions may be utilized, and the advantages and limitations of the gases tested to date will be presented and discussed. The separation and detection of the As, Se, and Cr species of interest can be achieved using the same chromatographic conditions in less than 2 minutes by complexing the Cr(III) with EDTA prior to injection on the HPLC column. Practical aspects of simultaneous speciation analysis will be presented and discussed, including issues with HPLC sample vial contamination, standard and sample contamination, species stability, and considerations regarding sample collection and preservation methods. The results of testing to determine the method's robustness to common concomitant element and anion effects will also be discussed. Finally, results will be presented using the method for the analysis of a variety of environmental and geological samples including waters, soil leachates and simulated bio-fluid leachates.

  7. Characterisation of spent nuclear fuels by an on-line coupled HPLC-ICP-MS system

    International Nuclear Information System (INIS)

    Guenther-Leopold, I.; Gabler, F.; Wernli, B.; Kopajtic, Z.

    2000-01-01

    The determination of burn-up is one of the essential components of post-irradiation examination of nuclear fuel samples. In the framework of the ARIANE programme (Actinides Research in a Nuclear Element), at PSI the analysis of the isotopic vectors of uranium, plutonium, neodymium and some other fission and spallation products was carried out for the first time in the Hot Lab using high-performance liquid chromatography (HPLC), coupled on-line with an inductively coupled plasma mass spectrometer (ICP-MS). The results of these investigations, a comparison with the classical technique for burn-up determination, the advantages and limitations of the new method, the accuracy and precision of these types of analyses, the applicability of the technique to other samples and separation problems, and conclusions for further analyses of nuclear fuel samples, are here presented. (authors)

  8. Arsenic-containing fatty acids and hydrocarbons in marine oils - determination using reversed-phase HPLC-ICP-MS and HPLC-qTOF-MS.

    Science.gov (United States)

    Sele, Veronika; Sloth, Jens J; Holmelid, Bjarte; Valdersnes, Stig; Skov, Kasper; Amlund, Heidi

    2014-04-01

    Arsenolipids are the major arsenic species present in marine oils. Several structures of arsenolipids have been elucidated the last 5 years, demonstrating the chemical complexity of this trace element in the marine environment. Several commercial fish oils and marine oils, ranging in total arsenic concentrations from 1.6 to 12.5 mg kg(-1) oil, were analyzed for arsenolipids using reversed-phase high performance liquid chromatography coupled with inductively coupled plasma mass spectrometry (HPLC-ICP-MS). The arsenolipids were quantified using three different arsenic-containing calibration standards; dimethylarsinate (DMA), triphenylarsinoxide (Ph₃AsO) and a synthesized arsenic-containing hydrocarbon (AsHC) (dimethylarsinoyl nonadecane; C₂₁H₄₃AsO). The observed variation in signal intensity for arsenic during the gradient elution profile in reversed-phase HPLC was compensated for by determining the time-resolved response factors for the arsenolipids. Isotopes of germanium ((74)Ge) and indium ((115)In) were suited as internal standards for arsenic, and were used for verification of the arsenic signal response factors during the gradient elution. Dimethylarsinate was the most suitable calibration standard for the quantification of arsenolipids, with recoveries between 91% and 104% compared to total arsenic measurements in the same extracts. A range of marine oils was investigated, including oils of several fish species, cod liver and seal, as well as three commercial fish oils. The AsHCs - C₁₇H₃₈AsO, C₁₉H₄₂AsO and C₂₃H₃₈AsO - were identified as the major arsenolipids in the extracts of all oils by HPLC coupled with quadrupole time-of-flight mass spectrometry (qTOF-MS). Minor amounts of two arsenic-containing fatty acids (AsFAs) (C₂₃H₃₈AsO₃ and C₂₄H₃₈AsO₃) were also detected in the oils. The sum of the AsHCs and the AsFAs determined in the present study accounted for 17-42% of the total arsenic in the oils

  9. Separation of organic and inorganic arsenic species by HPLC-ICP-MS

    Energy Technology Data Exchange (ETDEWEB)

    Londesborough, S. [University of Helsinki, Department of Chemistry (Finland); Mattusch, J.; Wennrich, R. [UFZ-Centre for Environmental Research Leipzig-Halle, Department of Analytical Chemistry, Leipzig (Germany)

    1999-03-01

    The HPLC separation of eight anionic, cationic or neutral arsenic species (arsenite, arsenate, monomethylarsonic acid, dimethylarsinic acid, arsenobetaine, arsenocholine, trimethylarsine oxide and tetramethylarsonium ion) on a high-capacity, anion-exchange column (Ion Pac AS 7, Dionex) was studied. The separation was performed during one run with a nitric acid gradient ranging from pH 4-1.3. The influence of sodium dodecyl sulfate (SDS), sodium octyl sulfate (SOS) and 1,2-benzenedisulfonic acid (BDSA) as ion pairing eluent modifiers was investigated. In addition the effect of elevated temperatures (30 to 40 C) was studied. The best results were obtained at room temperature of 20 C with 0.05 mM benzenedisulfonic acid as the eluent modifier. The chromatograph was connected to an ICP-MS via a cross-flow nebulizer. Detection limits obtained with the optimized chromatographic separation were 0.16-0.60 {mu}g As L{sup -1} for different species. The proposed speciation method was applied to the determination of arsenic species in the DORM-2 reference material (Dogfish Muscle) and in aqueous extracts of mushrooms collected on arsenic contaminated ground. (orig.) With 7 figs., 4 tabs., 17 refs.

  10. HPLC-ICP-MS speciation analysis and risk assessment of arsenic in Cordyceps sinensis.

    Science.gov (United States)

    Zuo, Tian-Tian; Li, Yao-Lei; Jin, Hong-Yu; Gao, Fei; Wang, Qi; Wang, Ya-Dan; Ma, Shuang-Cheng

    2018-01-01

    Cordyceps sinensis , one of the most valued traditional herbal medicines in China, contains high amount of arsenic. Considering the adverse health effects of arsenic, this is of particular concern. The aim of this study was to determine and analyze arsenic speciation in C. sinensis , and to measure the associated human health risks. We used microwave extraction and high-performance liquid chromatography coupled with inductively coupled plasma mass spectrometry to determine and analyze the arsenic content in C. sinensis , and measured the associated human health risks according to the hazard index (HI), lifetime cancer risk (CR), and target hazard quotient (THQ). The main arsenic speciation in C. sinensis were not the four organic arsenic compounds, including dimethyl arsenic, monomethyl arsenic, arsenobetaine, and arsenocholine, but comprised inorganic arsenic and other unknown risk arsenic compounds. HI scores indicated that the risk of C. sinensis was acceptable. CR results suggested that the cancer risk was greater than the acceptable lifetime risk of 10 -5 , even at low exposure levels. THQ results indicated that at the exposure level  3.0 months/year, the systemic effects of the arsenic in C. sinensis was of great concern. The arsenic in C. sinensis might not be free of risks. The suggested C. sinensis consumption rate of 2.0 months/year provided important insights into the ways by which to minimize potential health risks. Our study not only played the role of "cast a brick to attract jade" by which to analyze arsenic speciation in C. sinensis but also offered a promising strategy of risk assessment for harmful residues in traditional herbal medicines.

  11. Speciation of As(III), As(V), MMA and DMA in contaminated soil extracts by HPLC-ICP/MS

    Energy Technology Data Exchange (ETDEWEB)

    Bissen, M.; Frimmel, F.H. [Engler-Bunte-Institut, Univ. Karlsruhe (Germany)

    2000-05-01

    A method to separate and quantify two inorganic arsenic species As(III) and As(V) and two organic arsenic species, monomethylarsonic acid (MMA) and dimethylarsinic acid (DMA), by HPLC-ICP/MS has been developed. The separation of arsenic species was achieved on the anionic exchange column IonPac {sup trademark} AS11 (Dionex) with NaOH as mobile phase. The technique was successfully applied to analyze extracts of two contaminated soils, sampled at a former tannery site (soil 1) and a former paint production site (soil 2). The soils were extracted at pH values similar to the natural environment. Extractions were performed at different pH values with 0.3 M ammonium oxalate (pH = 3), milli-Q water (pH = 5.8), 0.3 M sodium carbonate (pH = 8) and 0.3 M sodium bicarbonate (pH = 11). No organically bound arsenic was found in the extracts. As(V) was the major component. Only up to 0.04% of the total arsenic contained in soil 1 were mobilized. The highest amount of extracted arsenic was found at the highest pH. In the milli-Q water extract of soil 1 As(III) and As(V) were found. High amounts of As(V) were found in the extracts of soil 2. Up to 20% of the total arsenic bound to soil 2 constituents were released. The results show that the mobilization of arsenic depended on the pH value of the extraction solution and the kind of extracted soil. Dramatic consequences have to be expected for pH changes in the environment especially in cases where soils contain high amounts of mobile arsenic. (orig.)

  12. Determination of Arsenic Species in Ophiocordyceps sinensis from Major Habitats in China by HPLC-ICP-MS and the Edible Hazard Assessment.

    Science.gov (United States)

    Guo, Lian-Xian; Zhang, Gui-Wei; Wang, Jia-Ting; Zhong, Yue-Ping; Huang, Zhi-Gang

    2018-04-26

    This study sought to determine the concentration and distribution of arsenic (As) species in Ophiocordyceps sinensis ( O. sinensis ), and to assess its edible hazard for long term consumption. The total arsenic concentrations, measured through inductively coupled plasma mass spectrometry (ICP-MS), ranged from 4.00 mg/kg to 5.25 mg/kg. As determined by HPLC-ICP-MS, the most concerning arsenic species—AsB, MMA V , DMA V , As V , and As Ш —were either not detected (MMA V and DMA V ) or were detected as minor As species (AsB: 1.4⁻2.9%; As V : 1.3⁻3.2%, and As Ш : 4.1⁻6.0%). The major components were a cluster of unknown organic As (uAs) compounds with As Ш , which accounted for 91.7⁻94.0% of the As content. Based on the H₂O₂ test and the chromatography behavior, it can be inferred that, the uAs might not be toxic organic As. Estimated daily intake ( EDI) , hazard quotient ( HQ ), and cancer risk ( CR ) caused by the total As content; the sum of inorganic As (iAs) and uAs, namely i+uAs; and iAs exposure from long term O. sinensis consumption were calculated and evaluated through equations from the US Environmental Protection Agency and the uncertainties were analyzed by Monte-Carlo Simulation (MCS). EDI total As and EDI i+uAs are approximately ten times more than EDI iAs ; HQ total As and HQ i+u As > 1 while HQ i As 1 × 10 −4 while CR iAs iAs is very low.

  13. Comparative evaluation of ICP sample introduction systems to be used in the metabolite profiling of chlorine-containing pharmaceuticals via HPLC-ICP-MS.

    Science.gov (United States)

    Klencsár, Balázs; Sánchez, Carlos; Balcaen, Lieve; Todolí, José; Lynen, Frederic; Vanhaecke, Frank

    2018-05-10

    A systematic evaluation of four different ICP sample introduction systems to be used in the context of metabolite profiling of chlorine-containing pharmaceuticals via HPLC-ICP-MS was carried out using diclofenac and its major metabolite, 4'-hydroxy-diclofenac, as model compounds. The strict requirements for GMP validation of chromatographic methods in the pharmaceutical industry were adhered to in this context. The final aim of this investigation is an extension of the applicability and validatability of HPLC-ICP-MS in the field of pharmaceutical R&D. Five different gradient programmes were tested while the baseline peak width (w b ), peak capacity (P), USP tailing factor (A s ) and USP signal-to-noise ratio (USP S/N) were determined as major indicators of the chromatographic performance and the values obtained were compared to the corresponding FDA recommendations (if applicable). Four different ICP-MS sample introductions systems were investigated involving two units typically working at higher flow rates (∼1.0 mL min -1 ) and another two systems working at lower flow rates (∼0.1 mL min -1 ). Optimal conditions with potential for applicability under GMP conditions were found at a mobile phase flow rate of 1.0 mL min -1 by using a pneumatic micro-flow LC nebulizer mounted onto a Peltier-cooled cyclonic spray chamber cooled to -1 °C for sample introduction. Under these conditions, HPLC-ICP-MS provided a chromatographic performance similar to that of HPLC with UV detection. The peak shape (USP tailing factor = 1.1-1.4) was significantly improved compared to that obtained with the Peltier-cooled Scott-type spray chamber. Two alternative sample introduction systems - a POINT ® and a High-Temperature Torch-Integrated Sample Introduction System (hTISIS) - were also tested at a flow rate of 0.1 mL min -1 using a chromatographic column with 1.0 mm ID. Although these systems allowed the peak shape to be improved compared to that obtained with

  14. Determination of Arsenic Species in Ophiocordyceps sinensis from Major Habitats in China by HPLC-ICP-MS and the Edible Hazard Assessment

    Directory of Open Access Journals (Sweden)

    Lian-Xian Guo

    2018-04-01

    Full Text Available This study sought to determine the concentration and distribution of arsenic (As species in Ophiocordyceps sinensis (O. sinensis, and to assess its edible hazard for long term consumption. The total arsenic concentrations, measured through inductively coupled plasma mass spectrometry (ICP-MS, ranged from 4.00 mg/kg to 5.25 mg/kg. As determined by HPLC-ICP-MS, the most concerning arsenic species—AsB, MMAV, DMAV, AsV, and AsШ—were either not detected (MMAV and DMAV or were detected as minor As species (AsB: 1.4–2.9%; AsV: 1.3–3.2%, and AsШ: 4.1–6.0%. The major components were a cluster of unknown organic As (uAs compounds with AsШ, which accounted for 91.7–94.0% of the As content. Based on the H2O2 test and the chromatography behavior, it can be inferred that, the uAs might not be toxic organic As. Estimated daily intake (EDI, hazard quotient (HQ, and cancer risk (CR caused by the total As content; the sum of inorganic As (iAs and uAs, namely i+uAs; and iAs exposure from long term O. sinensis consumption were calculated and evaluated through equations from the US Environmental Protection Agency and the uncertainties were analyzed by Monte-Carlo Simulation (MCS. EDItotal As and EDIi+uAs are approximately ten times more than EDIiAs; HQtotal As and HQi+uAs > 1 while HQiAs < 1; and CRtotal As and CRi+uAs > 1 × 10−4 while CRiAs < 1 × 10−4. Thus, if the uAs is non-toxic, there is no particular risk to local consumers and the carcinogenic risk is acceptable for consumption of O. sinensis because the concentration of toxic iAs is very low.

  15. Comparison of GC-ICP-MS and HPLC-ICP-MS for species-specific isotope dilution analysis of tributyltin in sediment after accelerated solvent extraction

    International Nuclear Information System (INIS)

    Wahlen, Raimund; Wolff-Briche, Celine

    2003-01-01

    This study describes a direct comparison of GC and HPLC hyphenated to ICP-MS determination of tributyltin (TBT) in sediment by species-specific isotope dilution analysis (SS-IDMS). The certified reference sediment PACS-2 (NRC, Canada) and a candidate reference sediment (P-18/HIPA-1) were extracted using an accelerated solvent extraction (ASE) procedure. For comparison of GC and LC methods an older bottle of PACS-2 was used, whilst a fresh bottle was taken for demonstration of the accuracy of the methods. The data obtained show good agreement between both methods for both the PACS-2 sediment (LC-ICP-IDMS 828±87 ng g -1 TBT as Sn, GC-ICP-IDMS 848±39 ng g -1 TBT as Sn) and the P-18/ HIPA-1 sediment (LC-ICP-IDMS 78.0±9.7 ng g -1 TBT as Sn, GC-ICP-IDMS 79.2±3.8 ng g -1 TBT as Sn). The analysis by GC-ICP-IDMS offers a greater signal-to-noise ratio and hence a superior detection limit of 0.03 pg TBT as Sn, in the sediment extracts compared to HPLC-ICP-IDMS (3 pg TBT as Sn). A comparison of the uncertainties associated with both methods indicates superior precision of the GC approach. This is related to the better reproducibility of the peak integration, which affects the isotope ratio measurements used for IDMS. The accuracy of the ASE method combined with HPLC-ICP-IDMS was demonstrated during the international interlaboratory comparison P-18 organised by the Comite Consultatif pour la Quantite de Matiere (CCQM). The results obtained by GC-ICP-IDMS for a newly opened bottle of PACS-2 were 1087±77 ng g -1 Sn for DBT and 876±51 ng g -1 Sn for TBT (expanded uncertainties with a coverage factor of 2), which are in good agreement with the certified values of 1090±150 ng g -1 Sn and 980±130 ng g -1 Sn, respectively. (orig.)

  16. Development of analytical procedures for determination of total chromium by quadrupole ICP-MS and high-resolution ICP-MS, and hexavalent chromium by HPLC-ICP-MS, in different materials used in the automotive industry.

    Science.gov (United States)

    Séby, F; Gagean, M; Garraud, H; Castetbon, A; Donard, O F X

    2003-10-01

    A European directive was recently adopted limiting the use of hazardous substances such as Pb, Hg, Cd, and Cr(VI) in vehicle manufacturing. From July 2003 a maximum of 2 g Cr(VI) will be authorised per vehicle in corrosion-preventing coatings of key components. As no standardised procedures are available to check if produced vehicles are in agreement with this directive, the objective of this work was to develop analytical procedures for total chromium and Cr(VI) determination in these materials. The first step of this study was to optimise digestion procedures for total chromium determination in plastic and metallic materials by inductively coupled plasma mass spectrometry (ICP-MS). High resolution (HR) ICP-MS was used to examine the influence of polyatomic interferences on the detection of the (52)Cr(+) and (53)Cr(+) isotopes. If there was strong interference with m/ z 52 for plastic materials, it was possible to use quadrupole ICP-MS for m/ z 53 if digestions were performed with HNO(3)+H(2)O(2). This mixture was also necessary for digestion of chromium from metallic materials. Extraction procedures in alkaline medium (NH(4)(+)/NH(3) buffer solution at pH 8.9) assisted by sonication were developed for determining Cr(VI) in four different corrosion-preventing coatings by HPLC-ICP-MS. After optimisation and validation with the only solid reference material certified for its Cr(VI) content (BCR 545; welding dusts), the efficiency of this extraction procedure for screw coatings was compared with that described in the EN ISO 3613 standard generally used in routine laboratories. For coatings comprising zinc and aluminium passivated in depth with chromium oxides the extraction procedure developed herein enabled determination of higher Cr(VI) concentrations. This was also observed for the screw covered with a chromium passivant layer on zinc-nickel. For coating comprising a chromium passivant layer on alkaline zinc the standardized extraction procedure was more efficient

  17. Improvement of accuracy for the quantitation of selenoproteins in post-column isotope dilution technique with HPLC ICP/MS

    International Nuclear Information System (INIS)

    Kim, Soo Jin; Pak, Yong Nam

    2016-01-01

    Post-column isotope dilution (PCID) or species-unspecific isotope dilution (ID) is a very useful quantitative technique in chromatography hyphenated with inductively coupled plasma–mass spectrometer (ICP/MS). In quantitative analysis, the calibration curve method is the most common one. However, it is not an absolute technique for the determination of concentration for the samples. ID method is the absolute one for the quantitative measurement technique, which means the quantity could be determined by the fundamental unit such as weight. To use the technique, it needs some requirements and there are several restrictions especially in the application for high-performance liquid chromatography (HPLC). The impurities in eluting solvent were in question. Thus, different purity of AA was examined and the result is shown in Figure 3. Figure 3(a) is the one for low (98%) and Figure 3(b) is high (99.999%) purity AA. The dotted area is for the eluting solvent. When low purity of 98% AA was introduced, the background was increasing while it remained the same for high-purity AA

  18. Improvement of accuracy for the quantitation of selenoproteins in post-column isotope dilution technique with HPLC ICP/MS

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Soo Jin; Pak, Yong Nam [Dept. of Chemistry Education, Korea National University of Education, Cheongju (Korea, Republic of)

    2016-11-15

    Post-column isotope dilution (PCID) or species-unspecific isotope dilution (ID) is a very useful quantitative technique in chromatography hyphenated with inductively coupled plasma–mass spectrometer (ICP/MS). In quantitative analysis, the calibration curve method is the most common one. However, it is not an absolute technique for the determination of concentration for the samples. ID method is the absolute one for the quantitative measurement technique, which means the quantity could be determined by the fundamental unit such as weight. To use the technique, it needs some requirements and there are several restrictions especially in the application for high-performance liquid chromatography (HPLC). The impurities in eluting solvent were in question. Thus, different purity of AA was examined and the result is shown in Figure 3. Figure 3(a) is the one for low (98%) and Figure 3(b) is high (99.999%) purity AA. The dotted area is for the eluting solvent. When low purity of 98% AA was introduced, the background was increasing while it remained the same for high-purity AA.

  19. Development and validation of a simple and robust method for arsenic speciation in human urine using HPLC/ICP-MS.

    Science.gov (United States)

    Sen, Indranil; Zou, Wei; Alvaran, Josephine; Nguyen, Linda; Gajek, Ryszard; She, Jianwen

    2015-01-01

    In order to better distinguish the different toxic inorganic and organic forms of arsenic (As) exposure in individuals, we have developed and validated a simple and robust analytical method for determining the following six As species in human urine: arsenous (III) acid (As-III), As (V) acid, monomethylarsonic acid, dimethylarsinic acid, arsenobetaine (AsB), and arsenocholine. In this method, human urine is diluted using a pH 5.8 buffer, separation is performed using an anion exchange column with isocratic HPLC, and detection is achieved using inductively coupled plasma-MS. The method uses a single mobile phase consisting of low concentrations of both phosphate buffer (5 mM) and ammonium nitrate salt (5 mM) at pH 9.0; this minimizes the column equilibration time and overcomes challenges with separation between AsB and As-III. In addition, As-III oxidation is prevented by degassing the sample preparation buffer at pH 5.8, degassing the mobile phase online at pH 9.0, and by the use of low temperature (-70 °C) and flip-cap airtight tubes for long term storage of samples. The method was validated using externally provided reference samples. Results were in agreement with target values at varying concentrations and successfully passed external performance test criteria. Internal QC samples were prepared and repeatedly analyzed to assess the method's long-term precision, and further analyses were completed on anonymous donor urine to assess the quality of the method's baseline separation. Results from analyses of external reference samples agreed with target values at varying concentrations, and results from precision studies yielded absolute CV values of 3-14% and recovery from 82 to 115% for the six As species. Analysis of anonymous donor urine confirmed the well-resolved baseline separation capabilities of the method for real participant samples.

  20. A systematic approach to the accurate quantification of selenium in serum selenoalbumin by HPLC-ICP-MS

    International Nuclear Information System (INIS)

    Jitaru, Petru; Goenaga-Infante, Heidi; Vaslin-Reimann, Sophie; Fisicaro, Paola

    2010-01-01

    In this paper, two different methods are for the first time systematically compared for the determination of selenium in human serum selenoalbumin (SeAlb). Firstly, SeAlb was enzymatically hydrolyzed and the resulting selenomethionine (SeMet) was quantified using species-specific isotope dilution (SSID) with reversed phase-HPLC (RP-HPLC) hyphenated to (collision/reaction cell) inductively coupled plasma-quadrupole mass spectrometry (CRC ICP-QMS). In order to assess the enzymatic hydrolysis yield, SeAlb was determined as an intact protein by affinity-HPLC (AF-HPLC) coupled to CRC ICP-QMS. Using this approach, glutathione peroxidase (GPx) and selenoprotein P (SelP) (the two selenoproteins present in serum) were also determined within the same chromatographic run. The levels of selenium associated with SeAlb in three serum materials, namely BCR-637, Seronorm level 1 and Seronorm level 2, obtained using both methods were in a good agreement. Verification of the absence of free SeMet, which interferes with the SeAlb determination (down to the amino acid level), in such materials was addressed by analyzing the fraction of GPx, partially purified by AF-HPLC, using RP-HPLC (GPx only) and size exclusion-HPLC (SE-HPLC) coupled to CRC ICP-QMS. The latter methodology was also used for the investigation of the presence of selenium species other than the selenoproteins in the (AF-HPLC) SelP and SeAlb fractions; the same selenium peaks were detected in both control and BCR-637 serum with a difference in age of ca. 12 years. It is also for the first time that the concentrations of selenium associated with SeAlb, GPx and SelP species in such commercially available serums (only certified or having indicative levels of total selenium content) are reported. Such indicative values can be used for reference purposes in future validation of speciation methods for selenium in human serum and/or inter-laboratory comparisons.

  1. A systematic approach to the accurate quantification of selenium in serum selenoalbumin by HPLC-ICP-MS

    Energy Technology Data Exchange (ETDEWEB)

    Jitaru, Petru, E-mail: Petru.Jitaru@lne.fr [Laboratoire National de Metrologie et d' Essais (LNE), Department of Biomedical and Inorganic Chemistry, 1 rue Gaston Boissier, 75015 Paris (France); Goenaga-Infante, Heidi [LGC Limited, Queens Road, Teddington, TW11 OLY, Middlesex (United Kingdom); Vaslin-Reimann, Sophie; Fisicaro, Paola [Laboratoire National de Metrologie et d' Essais (LNE), Department of Biomedical and Inorganic Chemistry, 1 rue Gaston Boissier, 75015 Paris (France)

    2010-01-11

    In this paper, two different methods are for the first time systematically compared for the determination of selenium in human serum selenoalbumin (SeAlb). Firstly, SeAlb was enzymatically hydrolyzed and the resulting selenomethionine (SeMet) was quantified using species-specific isotope dilution (SSID) with reversed phase-HPLC (RP-HPLC) hyphenated to (collision/reaction cell) inductively coupled plasma-quadrupole mass spectrometry (CRC ICP-QMS). In order to assess the enzymatic hydrolysis yield, SeAlb was determined as an intact protein by affinity-HPLC (AF-HPLC) coupled to CRC ICP-QMS. Using this approach, glutathione peroxidase (GPx) and selenoprotein P (SelP) (the two selenoproteins present in serum) were also determined within the same chromatographic run. The levels of selenium associated with SeAlb in three serum materials, namely BCR-637, Seronorm level 1 and Seronorm level 2, obtained using both methods were in a good agreement. Verification of the absence of free SeMet, which interferes with the SeAlb determination (down to the amino acid level), in such materials was addressed by analyzing the fraction of GPx, partially purified by AF-HPLC, using RP-HPLC (GPx only) and size exclusion-HPLC (SE-HPLC) coupled to CRC ICP-QMS. The latter methodology was also used for the investigation of the presence of selenium species other than the selenoproteins in the (AF-HPLC) SelP and SeAlb fractions; the same selenium peaks were detected in both control and BCR-637 serum with a difference in age of ca. 12 years. It is also for the first time that the concentrations of selenium associated with SeAlb, GPx and SelP species in such commercially available serums (only certified or having indicative levels of total selenium content) are reported. Such indicative values can be used for reference purposes in future validation of speciation methods for selenium in human serum and/or inter-laboratory comparisons.

  2. Separation and identification of Se-methylselenogalactosamine - a new metabolite in basal human urine - by HPLC-ICP-MS and CE-nano-ESI-(MS)(2)

    DEFF Research Database (Denmark)

    Bendahl, L.; Gammelgaard, Bente

    2004-01-01

    Three minor metabolites were isolated from human urine. Two of these were identified by nano electrospray ionisation mass spectrometry (nESI-MS) as Se-methylseleno-N-acetylglucosamine and Se-methylselenogalactosamine, respectively. A human urine pool was lyophilised and reconstituted in methanol......-chromatographed in the reversed phase system and further purified in different separation systems before analysis by nESI-MS. By CE-nESI-MS analysis of one of the fractions, the characteristic selenium pattern was recognized around m/z 285 and ( MS) 2 fragmentation resulted in a fragments at m/z 267, 173 and 155, respectively....... It was not possible to identify this selenium compound on basis of the available data. The selenium compound in the second fraction showed co-elution with a Se-methylseleno-N-acetylglucosamine standard. The identity of this compound was verified by nESI-MS after further purification by size exclusion chromatography...

  3. Separation, purification and identification of the major selenium metabolite from human urine by multi-dimensional HPLC-ICP-MS and APCI-MS

    DEFF Research Database (Denmark)

    Gammelgaard, Bente; Madsen, K.G.; Bjerrum, J.

    2003-01-01

    volunteers were collected and analysed by ion-pair chromatography with ICP-MS detection for this major selenium metabolite. Samples containing the metabolite were pooled and solid phase extracted to remove ionic substances. The extracted pool was purified and preconcentrated twice by preparative reversed...

  4. Identification and quantification of metallothionein isoforms and superoxide dismutase in spiked liver extracts using HPLC-ESI-MS offline coupling and HPLC-ICP-MS online coupling.

    Science.gov (United States)

    Nischwitz, V; Michalke, B; Kettrup, A

    2003-01-01

    A two-dimensional chromatographic method for the characterization of metallothionein isoforms (MT) and superoxide dismutase (SOD) in spiked liver extracts was developed for the optimization of extraction procedures from liver samples. Element-specific detection (ICP-MS) and molecule-specific detection (ESI-MS) were applied for maximum species information. A special focus was laid on the quantitative data evaluation (species stoichiometry, calibration with and without matrix, recovery), which is neglected in most MT/SOD publications with hyphenated techniques. Linearity, precision (residual standard deviation of calibration curves <10%), and detection limits (<0.6 mg L(-1) for MT isoforms and 13 mg L(-1) for SOD) prove the suitability of the method for quantification. An alternative quantification is proposed for the extension towards other lesser or even unknown trace element species, especially the native porcine MT and SOD.

  5. Metal components analysis of metallothionein-III in the brain sections of metallothionein-I and metallothionein-II null mice exposed to mercury vapor with HPLC/ICP-MS

    Energy Technology Data Exchange (ETDEWEB)

    Kameo, Satomi; Nakai, Kunihiko; Kurokawa, Naoyuki; Satoh, Hiroshi [Tohoku University, Graduate School of Medicine, Aoba-ku, Sendai (Japan); Kanehisa, Tomokazu; Naganuma, Akira [Tohoku University, Graduate School of Pharmaceutical Sciences, Sendai (Japan)

    2005-04-01

    variance. As for zinc, the copper concentrations only changed significantly in the cerebellum. Metal components of metal-binding proteins of soluble fractions in the brain sections were analyzed by size-exclusion high-performance liquid chromatography (HPLC) connected with ICP-MS. From the results of HPLC/ICP-MS analyses, it was concluded that the mercury components of MT-III and high molecular weight metal-binding proteins in the cerebellum of MT-I, II null mice were much higher than those of wild-type mice. It was suggested that MT-III is associated with the storage of mercury in conditions lacking MT-I, and MT-II. It was also suggested that the physiological role of MT-III and some kind of high molecular weight proteins might be impaired by exposure to mercury vapor and lack of MT-I and MT-II. (orig.)

  6. The impact of whole human blood on the kinetic inertness of platinum(iv) prodrugs - an HPLC-ICP-MS study.

    Science.gov (United States)

    Theiner, Sarah; Grabarics, Márkó; Galvez, Luis; Varbanov, Hristo P; Sommerfeld, Nadine S; Galanski, Markus; Keppler, Bernhard K; Koellensperger, Gunda

    2018-04-17

    The potential advantage of platinum(iv) complexes as alternatives to classical platinum(ii)-based drugs relies on their kinetic stability in the body before reaching the tumor site and on their activation by reduction inside cancer cells. In this study, an analytical workflow has been developed to investigate the reductive biotransformation and kinetic inertness of platinum(iv) prodrugs comprising different ligand coordination spheres (respectively, lipophilicity and redox behavior) in whole human blood. The distribution of platinum(iv) complexes in blood pellets and plasma was determined by inductively coupled plasma-mass spectrometry (ICP-MS) after microwave digestion. An analytical approach based on reversed-phase (RP)-ICP-MS was used to monitor the parent compound and the formation of metabolites using two different extraction procedures. The ligand coordination sphere of the platinum(iv) complexes had a significant impact on their accumulation in red blood cells and on their degree of kinetic inertness in whole human blood. The most lipophilic platinum(iv) compound featuring equatorial chlorido ligands showed a pronounced penetration into blood cells and a rapid reductive biotransformation. In contrast, the more hydrophilic platinum(iv) complexes with a carboplatin- and oxaliplatin-core exerted kinetic inertness on a pharmacologically relevant time scale with notable amounts of the compound accumulated in the plasma fraction.

  7. Stability studies of arsenic, selenium, antimony and tellurium species in water, urine, fish and soil extracts using HPLC/ICP-MS

    Energy Technology Data Exchange (ETDEWEB)

    Lindemann, T.; Prange, A.; Neidhart, B. [GKSS Research Centre, Geesthacht (Germany). Inst. of Physical and Chemical Analysis; Dannecker, W. [Hamburg Univ. (Germany). Inst. fuer Anorganische und Angewandte Chemie

    2000-10-01

    The stability of arsenic, selenium, antimony and tellurium species in water and urine (NIST SRM 2670n) as well as in extracts of fish and soil certified reference materials (DORM-2 and NIST SRM 2710) has been investigated. Stability studies were carried out with As(III), As(V), arsenobetaine, monomethylarsonic acid (MMA), dimethylarsinic acid (DMA), phenylarsonic acid (PAA), Se(IV), Se(VI), selenomethionine, Sb(III), Sb(V) and Te(VI). Speciation analysis was performed by on-line coupling of anion exchange high-performance liquid chromatography (HPLC) with inductively coupled plasma mass spectrometry (ICP-MS). Best storage of aqueous mixtures of the examined species was achieved at 3 C whereas at -20 C species transformation especially of selenomethionine and Sb(V) took place and a new selenium species appeared within a period of 30 days. Losses and species transformations during extraction processes were investigated. Extraction of the spiked fish material with methanol/water led to partial conversion of Sb(III), Sb(V) and selenomethionine to two new antimony and one new selenium species. The other arsenic, selenium and tellurium species were almost quantitatively extracted. For soil spiked with MMA, PAA, Se(IV) and Sb(III), recoveries after extraction with water and sulfuric acid (0.01 mol/L) were below 20%. (orig.)

  8. Application of on-line HPLC-ICP-MS for the determination of the nuclide abundances of lanthanides produced via spallation reactions in an irradiated tantalum target of a spallation neutron source

    International Nuclear Information System (INIS)

    Kerl, W.; Becker, J.S.; Dietze, H.J.

    1998-01-01

    An analytical procedure has been developed for the determination of spallation nuclides in an irradiated tantalum target using HPLC coupled on-line to ICP-MS after dissolution and separation of the tantalum matrix. Pieces of tantalum were taken from different locations of the irradiated tantalum target which had been used as the target material in a spallation neutron source. Tantalum was dissolved in a HNO 3 /HF mixture and the tantalum matrix was separated by liquid-liquid extraction so that only the spallation nuclides were left in the sample solutions. The major fraction of the spallation nuclides in the tantalum target are lanthanide metals in the μg g -1 concentration range determined in the present study. Additional reaction products are formed by the irradiation of trace impurities in the original tantalum target. The nuclide abundances of the lanthanide metals measured in the tantalum target differ significantly from the natural isotopic composition so that a lot of isobaric interferences of long-lived radionuclides and stable isotopes in the mass spectrum are to be expected. Therefore, all the lanthanide metals had to be separated chemically prior to their mass spectrometric determination. The separation of all rare earth elements was performed by ion chromatography on-line to ICP-MS. The nuclide abundances of each lanthanide were determined using a sensitive double-focusing sector field inductively coupled plasma mass spectrometer. The nuclide abundances of the lanthanides in the irradiated tantalum target calculated theoretically and the experimental results obtained by on-line HPLC-ICP-MS proved to be in good agreement. (orig.)

  9. Characterisation of selenium compounds in rye seedling biomass using {sup 75}Se-labelling/SDS-PAGE separation/{gamma}-scintillation counting, and HPLC-ICP-MS analysis of a range of enzymatic digests

    Energy Technology Data Exchange (ETDEWEB)

    Bryszewska, Malgorzata A. [Technical University of Lodz (Poland). Institute of General Food Chemistry; Ambroziak, Wojciech [Technical University of Lodz (Poland). Institute of Fermentation Technology and Microbiology; Rudzinski, Juliusz [Technical University of Lodz (Poland). Institute of Applied Radiation Chemistry; Lewis, D. John [Central Science Laboratory, York (United Kingdom)

    2005-07-01

    In the present study, selenium-enriched plant biomass was investigated to evaluate the ability of rye seedlings to take up, and assimilate, inorganic selenium. Two different analytical approaches were used. Electrophoretic separation (SDS-PAGE) of proteins extracted from {sup 75}Se-labelled biomass was used to investigate the biotransformation of selenite into organic forms of the element. Ion-pair chromatography coupled with ICP-MS detection was chosen for the analysis of selenium species, enzymatically extracted from the plant biomass. The results of three enzymatic hydrolysis procedures and three sequential enzymatic extractions procedures are compared. The most effective single extraction was proteolysis (using protease type XIV), giving an overall extraction efficiency of 48%. However, for combinations of enzymes, the most effective was cellulase (Trichoderma viride) followed by sequential extraction of the solid pellet using protease type XIV, giving an extraction efficiency of 70%. The complementary data from the electrophoretic fractionation of proteins, and the HPLC separation of Se-species in the proteolytic digests, reveal the existence of large number of selenium-containing compounds in the rye seedling plant biomass. The results showed the complete biotransformation of inorganic selenium into organic forms during germination of the rye seedlings. HPLC-ICP-MS analysis of extracts from the plant biomass did not show the presence of selenate or selenite. At the time of this study, the lack of suitable organic-MS facilities meant that it was not possible to characterise them fully. However, the data does show that a combination of different enzymes, rather than just the commonly-used protease, should be considered when developing an extraction strategy for selenium in different food types to those already reported in the literature. (orig.)

  10. Speciation of dimethylarsinyl-riboside derivatives (arsenosugars) in marine reference materials by HPLC-ICP-MS

    DEFF Research Database (Denmark)

    Larsen, Erik Huusfeldt

    1995-01-01

    (cf. Table 2) were present in shellfish certified reference materials (CRMs) and in a lobster hepatopancreas CRM. The concentration of the two arsenosugars in the shellfish samples amounts to 18% of the total arsenic as compared to arsenobetaine at 9–13% and dimethylarsinate at 4–9% of the total...

  11. Determination of organoarsenic species in marine samples using gradient elution cation exchange HPLC-ICP-MS

    DEFF Research Database (Denmark)

    Sloth, Jens Jørgen; Larsen, Erik Huusfeldt; Julshamn, Kåre

    2003-01-01

    and dimethylarsinoylacetic acid, whereas the cationic arsenocholine ion and tetramethylarsonium ion were not affected. The accuracy of the method for DMA, AsB and TMAs was validated with the CRMs DORM-2 and BCR626 Tuna. The concentrations found for arsenobetaine, dimethylarsinic acid and tetramethylarsonium ion were within...

  12. HPLC-ICP/MS Analysis of Thyroid Hormone and Related Iodinated Compounds in Tissues and Media

    Science.gov (United States)

    Quantifying thyroid hormone (TH) and the synthetic precursors and metabolic products of TH is important for developing models of the hypothalamic-pituitary-thyroid (HPT) axis as well as for understanding the effects of xenobiotics on HPT axis function. In this study, the developm...

  13. Determination of technetium-99 in soil samples by high performance liquid chromatography coupled to inductively coupled plasma mass spectrometry

    International Nuclear Information System (INIS)

    Muto, Toshio; Shimokawa, Toshinari

    1997-01-01

    A new powerful analytical technique viz. high performance liquid chromatography(HPLC) coupled to inductively coupled plasma mass spectrometry(HPLC/ICP-MS) has been applied to the determination of technetium-99( 99 Tc) in soils as a typical environmental sample. Technetium was enriched in a solution from incinerated soil samples by leaching in HNO 3 and passed through 'TEVA resin' column. The solution was injected into HPLC/ICP-MS system to eliminate the interfering elements (i.e. Ru and Mo) and to determine the 99 Tc concentration at the same time. The concentrations of 99 Tc in the incinerated soils were found to be 0.49Bq/kg(0.77ng/kg)-1.4Bq/kg(2.2ng/kg) with the determination limit of 0.02Bq/kg(0.03ng/kg(0.03ppt)). The results indicate the following findings; 1) the determination of 99 Tc by ICP-MS after strict elimination of the interfering elements by HPLC brings about the improvement in their reliability; 2) the detection limits identified are much lower compared with those by conventional ICP-MS methods because of the concentration of 99 Tc to smaller volume, which is due to only 100μl of samples could be measured by HPLC/ICP-MS system; 3) sample preparation could be simplified because of strict elimination of the interfering elements by HPLC. This research showed that HPLC/ICP-MS system is very effective to determine 99 Tc in environmental samples. (author)

  14. Speciation of Selenium in Selenium-Enriched Sunflower Oil by High-Performance Liquid Chromatography-Inductively Coupled Plasma Mass Spectrometry/Electrospray-Orbitrap Tandem Mass Spectrometry.

    Science.gov (United States)

    Bierla, Katarzyna; Flis-Borsuk, Anna; Suchocki, Piotr; Szpunar, Joanna; Lobinski, Ryszard

    2016-06-22

    The reaction of sunflower oil with selenite produces a complex mixture of selenitriglycerides with antioxidant and anticancer properties. To obtain insight into the identity and characteristics of the species formed, an analytical approach based on the combination of high-performance liquid chromatography (HPLC) with (78)Se-specific selenium detection by inductively coupled plasma mass spectrometry (ICP MS) and high-resolution (100 000), high mass accuracy (HPLC-ICP MS for the separation of a complex mixture of selenospecies and a mathematical correction of the background signal was developed. The identical chromatographic conditions served for the sample introduction into electrospray MS. Two types of samples were analyzed: sunflower oil dissolved in isopropanol and methanol extract of the oil containing 65% selenium. HPLC-ICP MS showed 14 peaks, 11 of which could also be detected in the methanol extract. Isotopic patterns corresponding to molecules with one or two selenium atoms could be attributed by Orbitrap MS at the retention times corresponding to the HPLC-ICP MS peak apexes. Structural data for these species were acquired by MS(2) and MS(3) fragmentation of protonated or sodiated ions using high-energy collisional dissociation (HCD). A total of 11 selenium-containing triglycerol derivatives resulting from the oxidation of one or two double bonds of linoleic acid and analogous derivatives of glycerol-mixed linoleate(s)/oleinate(s) have been identified for the first time. The presence of these species was confirmed by the targeted analysis in the total oil isopropanol solution. Their identification corroborated the predicted elution order in reversed-phase chromatography: LLL (glycerol trilinoleate), LLO (glycerol dilinoleate-oleinate), LOO (glycerol linoleate-dioleinate), OOO (glycerol trioleinate), of which the extrapolation allowed for the prediction of the identity [glycerol dioleinate-stearate (OOS) and glycerol oleinate-distearate (OSS)] of the

  15. Fast Determination of Toxic Arsenic Species in Food Samples Using Narrow-bore High-Performance Liquid-Chromatography Inductively Coupled Plasma Mass Spectrometry.

    Science.gov (United States)

    Terol, Amanda; Marcinkowska, Monika; Ardini, Francisco; Grotti, Marco

    2016-01-01

    A new method for the speciation analysis of arsenic in food using narrow-bore high-performance liquid-chromatography inductively coupled plasma mass spectrometry (HPLC-ICP-MS) has been developed. Fast separation of arsenite, arsenate, monomethylarsonic acid and dimethylarsinic acid was carried out in 7 min using an anion-exchange narrow-bore Nucleosil 100 SB column and 12 mM ammonium dihydrogen phosphate of pH 5.2 as the mobile phase, at a flow rate of 0.3 mL min(-1). A PFA-ST micronebulizer jointed to a cyclonic spray chamber was used for HPLC-ICP-MS coupling. Compared with standard-bore HPLC-ICP-MS, the new method has provided higher sensitivity, reduced mobile-phase consumption, a lower matrix plasma load and a shorter analysis time. The achieved instrumental limits of detection were in the 0.3 - 0.4 ng As mL(-1) range, and the precision was better than 3%. The arsenic compounds were efficiently (>80%) extracted from various food samples using a 1:5 methanol/water solution, with additional ultrasonic treatment for rice products. The applicability of this method was demonstrated by the analysis of several samples, such as seafood (fish, mussels, shrimps, edible algae) and rice-based products (Jasmine and Arborio rice, spaghetti, flour, crackers), including three certified reference materials.

  16. Selective arsenic speciation analysis of human urine reference materials using gradient elution ion-exchange HPLC-ICP-MS

    DEFF Research Database (Denmark)

    Sloth, Jens Jørgen; Larsen, Erik Huusfeldt; Julshamn, K.

    2004-01-01

    identical with the reference values given for total arsenic. The obtained values for arsenobetaine and dimethylarsinic acid were identical with the values certified for the NIES No. 18 urine CRM. The speciation data presented here may be valuable for the quality assurance of analytical method development...

  17. Arsenic speciation in soil using high performance liquid chromatography/inductively coupled plasma/mass spectrometry

    Energy Technology Data Exchange (ETDEWEB)

    Bass, D.A.; Yaeger, J.S.; Parish, K.J.; Crain, J.S.; Kiely, J.T.; Gowdy, M.J. [Argonne National Lab., IL (United States); Mohrman, G.B.; Besmer, M.G. [Rocky Mountain Arsenal, Commerce City, CO (United States)

    1996-08-01

    A method has been developed to identify and quantify As(III), As(V), and organoarsenic compounds in soil samples from the Rocky Mountain Arsenal (RMA) by high performance liquid chromatography/inductively coupled plasma/mass spectrometry (HPLC/ICP/MS). The soils were extracted using tetrabutylammonium hydroxide (TBAH) and sonication. The percentages of As(III), As(V), and organoarsenic species extracted from soil samples were 30, 50, and 100 respectively. The arsenic species were not altered during the extraction process. They were separated by reversed-phase, ion-pairing, HPLC using a microbore Inertsil-ODS{trademark} column. The HPLC column effluent was introduced into an ICP/MS system using a direct injection nebulizer (DIN). Detection limits of less than 1 pg were readily obtained for each arsenic species. Internal standards are recommended to increase accuracy and precision. Soil samples spiked with arsenic oxide, sodium arsenate, dimethylarsinic acid (DMAA), and chlorovinyl arsenious acid (CVAA) were extracted, identified and quantified with the HPLC/ICP/MS system. The soil samples were analyzed in support of the analytical needs of a thermal desorption treatability study being conducted at the RMA.

  18. EPA CRL MS014: Analysis of Aldicarb, Bromadiolone, Carbofuran, Oxamyl and Methomyl in Water by Multiple Reaction Monitoring Liquid Chromatography / Tandem Mass Spectrometry (LC/MS/MS)

    Science.gov (United States)

    Method MS014 describes procedures for solvent extraction of aldicarb, bromadiolone, carbofuran, oxamyl and methomyl from water samples, followed by analysis using liquid chromatography tandem mass spectrometry (LC-MS-MS).

  19. Speciation of Bio-Available Iodine in Abalone (Haliotis discus hannai) by High-Performance Liquid Chromatography Hyphenated with Inductively Coupled Plasma-Mass Spectrometry Using an In Vitro Method.

    Science.gov (United States)

    Doh, Han Sol; Park, Hyun Jin

    2018-06-01

    Abalone is one of the most valuable marine products found in East Asia because it is rich in nutritious substances including iodine. In this study, the in vitro dialyzability approach was used to assess the bio-available iodine species in abalone. Iodide, iodate, 3-iodo-L-tyrosine (MIT), and 3,5-diiodo-L-tyrosine (DIT) were separated by high-performance liquid chromatography hyphenated with inductively coupled plasma-mass spectrometry (HPLC-ICP-MS). To assure the consistency, reliability, and accuracy of the data, the method was validated. Comparison of the total iodine in abalone muscle and viscera indicated that abalone muscle showed greater digestion/absorption efficiency than abalone viscera (digestion efficiency: 68.13 ± 2.59% and 47.88 ± 5.76% and absorption efficiency: 59.78 ± 2.93% and 35.12 ± 1.43% for abalone viscera and muscle, respectively). However, evaluation of the sum of the analyzed iodine species targeted in this study by HPLC-ICP-MS indicated that abalone muscle showed lower digestion efficiency and similar absorption efficiency compared to that of abalone viscera (digestion efficiency: 35.52 ± 5.41% and 28.84 ± 1.83%; absorption efficiency: 23.56 ± 4.38% and 27.56 ± 1.51% for abalone viscera and muscle, respectively). The main forms of iodine detected in abalone muscle were iodide and MIT, whereas iodide was the major form in abalone viscera. The bio-available iodine in abalone was quantified via an in vitro method employing HPLC-ICP-MS. The results of this study indicated that abalone is feasible as a new iodine source and may prospectively find application in iodine-fortified foods. © 2018 Institute of Food Technologists®.

  20. Inductively coupled plasma mass spectrometry (ICP-MS)

    International Nuclear Information System (INIS)

    Shimamura, Tadashi

    1997-01-01

    The period of investigation for the previous general remarks on the progress of ICP-MS was from January, 1991 to September, 1993. In the investigation of this time, for the object of the Chemical Abstracts from January, 1994 to September, 1996, retrieval was carried out by using the STN International. As the key words, ICP-MS, Inductively Coupled Plasma Mass Spectrometry or Inductively Coupled Plasma Mass Spectrometer was used. The number of hit was 373 in 1994, 462 in 1995, and 356 as of September, 1996, 1191 in total. The cumulative number of the papers from 1980 to 1996 is shown. It is known how rapidly the ICP-MS has pervaded as the means of analysis. In order to cope with the enormous number of papers, this time, it was decided to do the review by limiting to the papers which were published in the main journals deeply related to analytical chemistry. As to the tendency in the last three years, it is summarized as how to overcome the spectrum interference and matrix effect in the ICP-MS and the trend of using the ICP-MS as the high sensitivity detector for separation techniques. The technical basic research of the ICP-MS on spectrum interference, sample introduction method and others and the analysis of living body samples are reported. (K.I.)

  1. Method optimization and quality assurance in speciation analysis using high performance liquid chromatography with detection by inductively coupled plasma mass spectrometry

    DEFF Research Database (Denmark)

    Larsen, Erik Huusfeldt

    1998-01-01

    Achievement of optimum selectivity, sensitivity and robustness in speciation analysis using high performance liquid chromatography (HPLC) with inductively coupled mass spectrometry (ICP-MS) detection requires that each instrumental component is selected and optimized with a view to the ideal....... The optimized anion and cation exchange HPLC-ICP-MS systems were used for arsenic speciation in contaminated ground water and in an in-house shrimp reference sample. For the purpose of verification, HPLC coupled with tandem mass spectrometry with electrospray ionization was additionally used for arsenic...... a mass balance of the analytes in each fraction of the extraction procedure, by recovery of spikes and by employing and comparing independent techniques. The urgent need for reference materials certified for elemental species is stressed....

  2. SWATH Mass Spectrometry Performance Using Extended Peptide MS/MS Assay Libraries*

    Science.gov (United States)

    Wu, Jemma X.; Song, Xiaomin; Pascovici, Dana; Zaw, Thiri; Care, Natasha; Krisp, Christoph; Molloy, Mark P.

    2016-01-01

    The use of data-independent acquisition methods such as SWATH for mass spectrometry based proteomics is usually performed with peptide MS/MS assay libraries which enable identification and quantitation of peptide peak areas. Reference assay libraries can be generated locally through information dependent acquisition, or obtained from community data repositories for commonly studied organisms. However, there have been no studies performed to systematically evaluate how locally generated or repository-based assay libraries affect SWATH performance for proteomic studies. To undertake this analysis, we developed a software workflow, SwathXtend, which generates extended peptide assay libraries by integration with a local seed library and delivers statistical analysis of SWATH-quantitative comparisons. We designed test samples using peptides from a yeast extract spiked into peptides from human K562 cell lysates at three different ratios to simulate protein abundance change comparisons. SWATH-MS performance was assessed using local and external assay libraries of varying complexities and proteome compositions. These experiments demonstrated that local seed libraries integrated with external assay libraries achieve better performance than local assay libraries alone, in terms of the number of identified peptides and proteins and the specificity to detect differentially abundant proteins. Our findings show that the performance of extended assay libraries is influenced by the MS/MS feature similarity of the seed and external libraries, while statistical analysis using multiple testing corrections increases the statistical rigor needed when searching against large extended assay libraries. PMID:27161445

  3. Arsenic-containing fatty acids and hydrocarbons in marine oils - Determination using reversed-phase HPLC-ICP-MS and HPLC-qTOF-MS

    DEFF Research Database (Denmark)

    Sele, Veronika; Sloth, Jens Jørgen; Holmelid, Bjarte

    2014-01-01

    ; dimethylarsinate (DMA), triphenylarsinoxide (Ph3AsO) and a synthesized arsenic-containing hydrocarbon (AsHC) (dimethylarsinoyl nonadecane; C21H43AsO). The observed variation in signal intensity for arsenic during the gradient elution profile in reversed-phase HPLC was compensated for by determining the time...

  4. Methods in endogenous steroid profiling - A comparison of gas chromatography mass spectrometry (GC-MS) with supercritical fluid chromatography tandem mass spectrometry (SFC-MS/MS).

    Science.gov (United States)

    Teubel, Juliane; Wüst, Bernhard; Schipke, Carola G; Peters, Oliver; Parr, Maria Kristina

    2018-06-15

    In various fields of endocrinology, the determination of steroid hormones synthesised by the human body plays an important role. Research on central neurosteroids has been intensified within the last years, as they are discussed as biomarkers for various cognitive disorders. Their concentrations in cerebrospinal fluid (CSF) are considered to be regulated independently from peripheral fluids. For that reason, the challenging matrix CSF becomes a very interesting specimen for analysis. Concentrations are expected to be very low and available amount of CSF is limited. Thus, a comprehensive method for very sensitive quantification of a set of analytes as large as possible in one analytical aliquot is desired. However, high structural similarities of the selected panel of 51 steroids and steroid sulfates, including numerous isomers, challenges achievement of chromatographic selectivity. Since decades the analysis of endogenous steroids in various body fluids is mainly performed by gas chromatography (GC) coupled to (tandem) mass spectrometry (MS(/MS)). Due to the structure of the steroids of interest, derivatisation is performed to meet the analytical requirements for GC-MS(/MS). Most of the laboratories use a two-step derivatisation in multi-analyte assays that was already published in the 1980s. However, for some steroids this elaborate procedure yields multiple isomeric derivatives. Thus, some laboratories utilize (ultra) high performance liquid chromatography ((U)HPLC)-MS/MS as alternative but, even UHPLC is not able to separate some of the isomeric pairs. Supercritical fluid chromatography (SFC) as an orthogonal separation technique to GC and (U)HPLC may help to overcome these issues. Within this project the two most promising methods for endogenous steroid profiling were investigated and compared: the "gold standard" GC-MS and the orthogonal separation technique SFC-MS/MS. Different derivatisation procedures for gas chromatographic detection were explored and the

  5. Determination of trace amounts of rare-earth elements in highly pure neodymium oxide by sector field inductively coupled plasma mass spectrometry (ICP-SFMS) and high-performance liquid chromatography (HPLC) techniques

    Science.gov (United States)

    Pedreira, W. R.; Sarkis, J. E. S.; da Silva Queiroz, C. A.; Rodrigues, C.; Tomiyoshi, I. A.; Abrão, A.

    2003-02-01

    Recently rare-earth elements (REE) have received much attention in fields of geochemistry and industry. Rapid and accurate determinations of them are increasingly required as industrial demands expand. Sector field inductively coupled plasma mass spectrometry (ICP-SFMS) with high-performance liquid chromatography (HPLC) has been applied to the determination of REE. HR ICP-MS was used as an element-selective detector for HPLC in highly pure materials. The separation of REE with HPLC helped to avoid erroneous analytical results due to spectral interferences. Sixteen elements (Sc, Y and 14 lanthanides) were determined selectively with the HPLC/ICP-SFMS system using a concentration gradient methods. The detection limits with the HPLC/ICP-SFMS system were about 0.5-10 pg mL-1. The percentage recovery ranged from 90% to 100% for different REE. The %RSD of the methods varying between 2.5% and 4.5% for a set of five (n=5) replicates was found for the IPEN's material and for the certificate reference sample. Determination of trace REEs in two highly pure neodymium oxides samples (IPEN and Johnson Matthey Company) were performed. In short, the IPEN's materials which are highly pure (>99.9%) were successfully analyzed without spectral interferences.

  6. Determination of trace amounts of rare-earth elements in highly pure neodymium oxide by sector field inductively coupled plasma mass spectrometry (ICP-SFMS) and high-performance liquid chromatography (HPLC) techniques

    International Nuclear Information System (INIS)

    Pedreira, W.R.; Sarkis, J.E.S.; Silva Queiroz, C.A. da; Rodrigues, C.; Tomiyoshi, I.A.; Abrao, A.

    2003-01-01

    Recently rare-earth elements (REE) have received much attention in fields of geochemistry and industry. Rapid and accurate determinations of them are increasingly required as industrial demands expand. Sector field inductively coupled plasma mass spectrometry (ICP-SFMS) with high-performance liquid chromatography (HPLC) has been applied to the determination of REE. HR ICP-MS was used as an element-selective detector for HPLC in highly pure materials. The separation of REE with HPLC helped to avoid erroneous analytical results due to spectral interferences. Sixteen elements (Sc, Y and 14 lanthanides) were determined selectively with the HPLC/ICP-SFMS system using a concentration gradient methods. The detection limits with the HPLC/ICP-SFMS system were about 0.5-10 pg mL -1 . The percentage recovery ranged from 90% to 100% for different REE. The %RSD of the methods varying between 2.5% and 4.5% for a set of five (n=5) replicates was found for the IPEN's material and for the certificate reference sample. Determination of trace REEs in two highly pure neodymium oxides samples (IPEN and Johnson Matthey Company) were performed. In short, the IPEN's materials which are highly pure (>99.9%) were successfully analyzed without spectral interferences

  7. Precise and accurate isotope ratio measurements by ICP-MS.

    Science.gov (United States)

    Becker, J S; Dietze, H J

    2000-09-01

    The precise and accurate determination of isotope ratios by inductively coupled plasma mass spectrometry (ICP-MS) and laser ablation ICP-MS (LA-ICP-MS) is important for quite different application fields (e.g. for isotope ratio measurements of stable isotopes in nature, especially for the investigation of isotope variation in nature or age dating, for determining isotope ratios of radiogenic elements in the nuclear industry, quality assurance of fuel material, for reprocessing plants, nuclear material accounting and radioactive waste control, for tracer experiments using stable isotopes or long-lived radionuclides in biological or medical studies). Thermal ionization mass spectrometry (TIMS), which used to be the dominant analytical technique for precise isotope ratio measurements, is being increasingly replaced for isotope ratio measurements by ICP-MS due to its excellent sensitivity, precision and good accuracy. Instrumental progress in ICP-MS was achieved by the introduction of the collision cell interface in order to dissociate many disturbing argon-based molecular ions, thermalize the ions and neutralize the disturbing argon ions of plasma gas (Ar+). The application of the collision cell in ICP-QMS results in a higher ion transmission, improved sensitivity and better precision of isotope ratio measurements compared to quadrupole ICP-MS without the collision cell [e.g., for 235U/238U approximately 1 (10 microg x L(-1) uranium) 0.07% relative standard deviation (RSD) vs. 0.2% RSD in short-term measurements (n = 5)]. A significant instrumental improvement for ICP-MS is the multicollector device (MC-ICP-MS) in order to obtain a better precision of isotope ratio measurements (with a precision of up to 0.002%, RSD). CE- and HPLC-ICP-MS are used for the separation of isobaric interferences of long-lived radionuclides and stable isotopes by determination of spallation nuclide abundances in an irradiated tantalum target.

  8. Determination of organic and inorganic mercury species in Sungai Kinta, Perak by reversed-phase high performance liquid chromatography (HPLC) on-line coupled with ICP-MS

    International Nuclear Information System (INIS)

    Norshidah Baharuddin; Norashikin Saim; Rozita Osman; Sharifuddin Mohd Zain

    2012-01-01

    This paper describes a simple method for mercury speciation in river water samples of Sungai Kinta, Perak. Separation and measurement were done by high-performance liquid chromatography on-line with inductively coupled plasma mass spectrometry (HPLC/ ICP-MS). Separation of mercury species was accomplished within 6 minutes on an AQ C18 4.6 mm i.d x 150 mm, 5 μm reversed phase column with 0.1 % (w/ v) L-cysteine as mobile phase. Under the optimum instrumental conditions, recoveries of 101-104 % for MeHg + and 96 - 104 % for Hg 2+ were obtained with experimental detection limits of 1ngL -1 for inorganic mercury and 1.5 μgL -1 for organic mercury. (author)

  9. Gas Chromatography (GC) – Mass Spectrometry (MS) analysis of ...

    African Journals Online (AJOL)

    MS. Glycosides, phenolics and alkaloids were indicated in large amount; eugenols and terpenes were also present while saponin, tannins and steroid were absent. Major components detected by GC-MS were 2-Hydroxy hexadecanoic acid ...

  10. Selective quantitation of the neurotoxin BMAA by use of hydrophilic-interaction liquid chromatography-differential mobility spectrometry-tandem mass spectrometry (HILIC-DMS-MS/MS).

    Science.gov (United States)

    Beach, Daniel G; Kerrin, Elliott S; Quilliam, Michael A

    2015-11-01

    The neurotoxin β-N-methylamino-L-alanine (BMAA) has been reported in cyanobacteria and shellfish, raising concerns about widespread human exposure. However, inconsistent results for BMAA analysis have led to controversy. Liquid chromatography-tandem mass spectrometry (LC-MS/MS) is the most appropriate method for analysis of BMAA, but the risk of interference from isomers, other sample components, and the electrospray background is still present. We have investigated differential mobility spectrometry (DMS) as an ion filter to improve selectivity in the hydrophilic interaction liquid chromatographic (HILIC)-MS/MS determination of BMAA. We obtained standards for two BMAA isomers not previously analyzed by HILIC-MS, β-amino-N-methylalanine and 3,4-diaminobutanoic acid, and the typically used 2,4-diaminobutanoic acid and N-(2-aminoethyl)glycine. DMS separation of BMAA from these isomers was achieved and optimized conditions were used to develop a sensitive and highly selective multidimensional HILIC-DMS-MS/MS method. This work revealed current technical limitations of DMS for trace quantitation, and practical solutions were implemented. Accurate control of low levels of DMS carrier gas modifier was essential, but required external metering. The linearity of our optimized method was excellent from 0.01 to 6 μmol L(-1). The instrumental LOD was 0.4 pg BMAA injected on-column and the estimated method LOD was 20 ng g(-1) dry weight for BMAA in sample matrix. The method was used to analyze cycad plant tissue, a cyanobacterial reference material, and mussel tissues, by use of isotope-dilution quantitation with deuterated BMAA. This confirmed the presence of BMAA and several of its isomers in cycad and mussel tissues, including commercially available mussel tissue reference materials certified for other biotoxins. Graphical Abstract Differential Mobility Spectrometry is used to increases the selectivity of BMAA analysis by HILIC-MS/MS.

  11. A rapid monitoring method for inorganic arsenic in rice flour using reversed phase-high performance liquid chromatography-inductively coupled plasma mass spectrometry.

    Science.gov (United States)

    Narukawa, Tomohiro; Chiba, Koichi; Sinaviwat, Savarin; Feldmann, Jörg

    2017-01-06

    A new rapid monitoring method by means of high performance liquid chromatography-inductively coupled plasma mass spectrometry (HPLC-ICP-MS) following the heat-assisted extraction was developed for measurement of total inorganic arsenic species in rice flour. As(III) and As(V) eluted at the same retention time and completely separated from organoarsenic species by an isocratic elution program on a reversed phase column. Therefore, neither ambiguous oxidation of arsenite to arsenate nor the integration of two peaks were necessary to determine directly the target analyte inorganic arsenic. Rapid injection allowed measuring 3 replicates within 6min and this combined with a quantitative extraction of all arsenic species from rice flour by a 15min HNO 3 -H 2 O 2 extraction makes this the fastest laboratory based method for inorganic arsenic in rice flour. Copyright © 2016 Elsevier B.V. All rights reserved.

  12. Ultra-Sensitive Elemental Analysis Using Plasmas 5.Speciation of Arsenic Compounds in Biological Samples by High Performance Liquid Chromatography-Inductively Coupled Plasma Mass Spectrometry System

    Science.gov (United States)

    Kaise, Toshikazu

    Arsenic originating from the lithosphere is widely distributed in the environment. Many arsenicals in the environment are in organic and methylated species. These arsenic compounds in drinking water or food products of marine origin are absorbed in human digestive tracts, metabolized in the human body, and excreted viatheurine. Because arsenic shows varying biological a spects depending on its chemical species, the biological characteristics of arsenic must be determined. It is thought that some metabolic pathways for arsenic and some arsenic circulation exist in aqueous ecosystems. In this paper, the current status of the speciation analysis of arsenic by HPLC/ICP-MS (High Performance Liquid Chromatography-Inductively Coupled Plasma Mass spectrometry) in environmental and biological samples is summarized using recent data.

  13. Quantitative HPLC-ICP-MS analysis of antimony redox speciation in complex sample matrices: new insights into the Sb-chemistry causing poor chromatographic recoveries

    DEFF Research Database (Denmark)

    Hansen, Claus; Schmidt, Bjørn; Larsen, Erik Huusfeldt

    2011-01-01

    In solution antimony exists either in the pentavalent or trivalent oxidation state. As Sb(III) is more toxic than Sb(V), it is important to be able to perform a quantitative speciation analysis of Sb’s oxidation state. The most commonly applied chromatographic methods used for this redox speciation...

  14. Chemical characterization of neonicotinoids in surface waters by high performance liquid chromatography with Tandem Mass Spectrometry (HPLC MS/MS)

    International Nuclear Information System (INIS)

    Amaral, Priscila Oliveira

    2017-01-01

    The present study aimed to develop a method for the determination and validation of a method for the identification and quantification of Neonicotinoids in surface waters collected in the Bauru region, in the state of São Paulo. The analytical techniques studied for the development of this method were the high performance liquid chromatography with tandem mass spectrometry (HPLC - MS / MS), gas chromatography with mass spectrometry (GC / MS) and gas chromatography with electron capture detector (GC / ECD). The class of pesticides Neonicotinoids was chosen for this work because it is related to a sudden disappearance of bees in colonies around the world. This phenomenon is known as Colony Collapse Disorder (CCD) and it is characterized by a rapid loss in the population of adult bees. The Neonicotinoids used in this study were the compounds Clothianidin, Imidacloprid and Thiamethoxam which were banned in their use as pesticides in Europe by Implementing Regulation No. 540/2011. The samples were concentrated using solid phase extraction (SPE) and liquid liquid extraction (LLE) techniques and injected into HPLC-MS / MS, GC / MS and GC / ECD. The GC / ECD and GC / MS techniques were not satisfactory for determination in the water matrix because the detection limit (10 mg L -1 ) is above the maximum allowed by the US Environmental Protection Agency (0.6 μg L -1 ). The HPLC - MS / MS technique using the multiple reaction monitoring (MRM) proved to be adequate for this study because it obtained quantification limits between 5.89 and 8.06 μg L -1 and a linearity between 0.9963 and 0.9999 for the three compounds. (author)

  15. METHOD 544. DETERMINATION OF MICROCYSTINS AND NODULARIN IN DRINKING WATER BY SOLID PHASE EXTRACTION AND LIQUID CHROMATOGRAPHY/TANDEM MASS SPECTROMETRY (LC/MS/MS)

    Science.gov (United States)

    Method 544 is an accurate and precise analytical method to determine six microcystins (including MC-LR) and nodularin in drinking water using solid phase extraction and liquid chromatography tandem mass spectrometry (SPE-LC/MS/MS). The advantage of this SPE-LC/MS/MS is its sensi...

  16. Quantitation of iothalamate in urine and plasma using liquid chromatography electrospray tandem mass spectrometry (HPLC-ESI-MS/MS).

    Science.gov (United States)

    Molinaro, Ross J; Ritchie, James C

    2010-01-01

    The following chapter describes a method to measure iothalamate in plasma and urine samples using high performance liquid chromatography combined with electrospray positive ionization tandem mass spectrometry (HPLC-ESI-MS/MS). Methanol and water are spiked with the internal standard (IS) iohexol. Iothalamate is isolated from plasma after IS spiked methanol extraction and from urine by IS spiked water addition and quick-spin filtration. The plasma extractions are dried under a stream of nitrogen. The residue is reconstituted in ammonium acetate-formic acid-water. The reconstituted plasma and filtered urine are injected into the HPLC-ESI-MS/MS. Iothalamate and iohexol show similar retention times in plasma and urine. Quantification of iothalamate in the samples is made by multiple reaction monitoring using the hydrogen adduct mass transitions, from a five-point calibration curve.

  17. Radionuclide content of simulated and fully radioactive SRLLL waste glasses: comparison of results from ICP-MS, gamma spectrometry and alpha spectrometry

    International Nuclear Information System (INIS)

    Wolf, S.F.; Bates, J.K.

    1995-01-01

    We have measured the transuranic content of two transuranic=doped, simulated waste glasses, using inductively coupled plasma-mass spectrometry (ICP-MS), γ-spectrometry, and α-spectrometry. Average concentrations measured by each technique were within ± 10% of the as-doped concentrations. We also report the transuranic content of three fully radioactive SRL waste glasses that were determined using γ- and α-spectrometry measurements to deconvolute isobaric interferences present in the ICP-MS analyses

  18. Simultaneous determination of creatinine and creatine in human serum by double-spike isotope dilution liquid chromatography-tandem mass spectrometry (LC-MS/MS) and gas chromatography-mass spectrometry (GC-MS).

    Science.gov (United States)

    Fernández-Fernández, Mario; Rodríguez-González, Pablo; Añón Álvarez, M Elena; Rodríguez, Felix; Menéndez, Francisco V Álvarez; García Alonso, J Ignacio

    2015-04-07

    This work describes the first multiple spiking isotope dilution procedure for organic compounds using (13)C labeling. A double-spiking isotope dilution method capable of correcting and quantifying the creatine-creatinine interconversion occurring during the analytical determination of both compounds in human serum is presented. The determination of serum creatinine may be affected by the interconversion between creatine and creatinine during sample preparation or by inefficient chemical separation of those compounds by solid phase extraction (SPE). The methodology is based on the use differently labeled (13)C analogues ((13)C1-creatinine and (13)C2-creatine), the measurement of the isotopic distribution of creatine and creatinine by liquid chromatography-tandem mass spectrometry (LC-MS/MS) and the application of multiple linear regression. Five different lyophilized serum-based controls and two certified human serum reference materials (ERM-DA252a and ERM-DA253a) were analyzed to evaluate the accuracy and precision of the proposed double-spike LC-MS/MS method. The methodology was applied to study the creatine-creatinine interconversion during LC-MS/MS and gas chromatography-mass spectrometry (GC-MS) analyses and the separation efficiency of the SPE step required in the traditional gas chromatography-isotope dilution mass spectrometry (GC-IDMS) reference methods employed for the determination of serum creatinine. The analysis of real serum samples by GC-MS showed that creatine-creatinine separation by SPE can be a nonquantitative step that may induce creatinine overestimations up to 28% in samples containing high amounts of creatine. Also, a detectable conversion of creatine into creatinine was observed during sample preparation for LC-MS/MS. The developed double-spike LC-MS/MS improves the current state of the art for the determination of creatinine in human serum by isotope dilution mass spectrometry (IDMS), because corrections are made for all the possible errors

  19. The utility of ultra-high performance supercritical fluid chromatography-tandem mass spectrometry (UHPSFC-MS/MS) for clinically relevant steroid analysis.

    Science.gov (United States)

    Storbeck, Karl-Heinz; Gilligan, Lorna; Jenkinson, Carl; Baranowski, Elizabeth S; Quanson, Jonathan L; Arlt, Wiebke; Taylor, Angela E

    2018-05-15

    Liquid chromatography tandem mass spectrometry (LC-MS/MS) assays are considered the reference standard for serum steroid hormone analyses, while full urinary steroid profiles are only achievable by gas chromatography (GC-MS). Both LC-MS/MS and GC-MS have well documented strengths and limitations. Recently, commercial ultra-high performance supercritical fluid chromatography-tandem mass spectrometry (UHPSFC-MS/MS) systems have been developed. These systems combine the resolution of GC with the high-throughput capabilities of UHPLC. Uptake of this new technology into research and clinical labs has been slow, possibly due to the perceived increase in complexity. Here we therefore present fundamental principles of UHPSFC-MS/MS and the likely applications for this technology in the clinical research setting, while commenting on potential hurdles based on our experience to date. Copyright © 2018 The Authors. Published by Elsevier B.V. All rights reserved.

  20. Determination of 4-Methylimidazole in Ammonia Caramel Using Gas Chromatography–Tandem Mass Spectrometry (GC-MS/MS

    Directory of Open Access Journals (Sweden)

    Martyna N. Wieczorek

    2018-01-01

    Full Text Available One of Maillard reaction products formed in the production of ammonia caramel is 4(5-methylimidazole (4-MeI classified as carcinogen. A method of 4-MeI determination based on ion-pair extraction and derivatisation with isobutyl chloroformate with subsequent gas chromatography-tandem mass spectrometry analysis was proposed. Tandem mass spectrometry was applied to reduce the influence of matrix and increase the selectivity and sensitivity of the method. Triple quadrupole GC-MS system was used for this study. The collision energies were optimized for MRM mode. The detection (LOD and quantification limits (LOQ of the elaborated method were 17 and 37.8 μg kg−1, respectively, repeatability was <15% RSD for analyzed caramel samples, and the recovery for 4-MeI was 101%. Comparison of MS/MS with SIM detection on the same instrument proved almost 30 times lower LODs achieved by tandem mass spectrometry compared to SIM. Described method can be routinely used for monitoring 4-MeI as a quality and safety marker in the production of ammonia caramel.

  1. Ion mobility spectrometry-mass spectrometry (IMS-MS) for on- and offline analysis of atmospheric gas and aerosol species

    Science.gov (United States)

    Krechmer, Jordan E.; Groessl, Michael; Zhang, Xuan; Junninen, Heikki; Massoli, Paola; Lambe, Andrew T.; Kimmel, Joel R.; Cubison, Michael J.; Graf, Stephan; Lin, Ying-Hsuan; Budisulistiorini, Sri H.; Zhang, Haofei; Surratt, Jason D.; Knochenmuss, Richard; Jayne, John T.; Worsnop, Douglas R.; Jimenez, Jose-Luis; Canagaratna, Manjula R.

    2016-07-01

    Measurement techniques that provide molecular-level information are needed to elucidate the multiphase processes that produce secondary organic aerosol (SOA) species in the atmosphere. Here we demonstrate the application of ion mobility spectrometry-mass spectrometry (IMS-MS) to the simultaneous characterization of the elemental composition and molecular structures of organic species in the gas and particulate phases. Molecular ions of gas-phase organic species are measured online with IMS-MS after ionization with a custom-built nitrate chemical ionization (CI) source. This CI-IMS-MS technique is used to obtain time-resolved measurements (5 min) of highly oxidized organic molecules during the 2013 Southern Oxidant and Aerosol Study (SOAS) ambient field campaign in the forested SE US. The ambient IMS-MS signals are consistent with laboratory IMS-MS spectra obtained from single-component carboxylic acids and multicomponent mixtures of isoprene and monoterpene oxidation products. Mass-mobility correlations in the 2-D IMS-MS space provide a means of identifying ions with similar molecular structures within complex mass spectra and are used to separate and identify monoterpene oxidation products in the ambient data that are produced from different chemical pathways. Water-soluble organic carbon (WSOC) constituents of fine aerosol particles that are not resolvable with standard analytical separation methods, such as liquid chromatography (LC), are shown to be separable with IMS-MS coupled to an electrospray ionization (ESI) source. The capability to use ion mobility to differentiate between isomers is demonstrated for organosulfates derived from the reactive uptake of isomers of isoprene epoxydiols (IEPOX) onto wet acidic sulfate aerosol. Controlled fragmentation of precursor ions by collisionally induced dissociation (CID) in the transfer region between the IMS and the MS is used to validate MS peak assignments, elucidate structures of oligomers, and confirm the

  2. JS-MS: a cross-platform, modular javascript viewer for mass spectrometry signals.

    Science.gov (United States)

    Rosen, Jebediah; Handy, Kyle; Gillan, André; Smith, Rob

    2017-11-06

    Despite the ubiquity of mass spectrometry (MS), data processing tools can be surprisingly limited. To date, there is no stand-alone, cross-platform 3-D visualizer for MS data. Available visualization toolkits require large libraries with multiple dependencies and are not well suited for custom MS data processing modules, such as MS storage systems or data processing algorithms. We present JS-MS, a 3-D, modular JavaScript client application for viewing MS data. JS-MS provides several advantages over existing MS viewers, such as a dependency-free, browser-based, one click, cross-platform install and better navigation interfaces. The client includes a modular Java backend with a novel streaming.mzML parser to demonstrate the API-based serving of MS data to the viewer. JS-MS enables custom MS data processing and evaluation by providing fast, 3-D visualization using improved navigation without dependencies. JS-MS is publicly available with a GPLv2 license at github.com/optimusmoose/jsms.

  3. Progress in determination of long-lived radionuclides by inductively coupled plasma mass spectrometry

    International Nuclear Information System (INIS)

    Becker, J.S.; Dietze, H.J.

    2000-01-01

    Mass spectrometric methods (such as inductively coupled plasma mass spectrometry - ICP-MS and laser ablation (LA)-ICP-MS) with their ability to provide a very sensitive multielemental and precise isotopic analysis have become established for the determination of radionuclides in quite different sample materials. The determination of long-lived radionuclides is of increasing interest for the characterization of radioactive waste materials and for the detection of radionuclide contamination in environmental materials in which several radioactive nuclides are present from fallout due to nuclear weapons testing, nuclear power plants or nuclear accidents. Due to its multielement capability, excellent sensitivity, low detection limits (up to sub pg I 1 range), very good precision, easy sample preparation and measurement procedures ICP-MS of aqueous solutions has been increasingly applied for the ultrasensitive determination of long-lived radionuclides such as 99 Tc, 129 I, 230 Th, 232 Th, 234 U, 235 U, 236 U, 239 Pu, 240 Pu and 241 Am and precise isotope ratio measurements of U,Th and Pu. The application especially of microanalytical methods (analysis of some MU by flow injection and on-line coupling techniques as capillary electrophoresis (CE-ICP-MS) or HPLC-ICP-MS) for the precise determination nuclide abundances and concentration of long-lived radionuclides at ultra trace concentration levels in radioactive waste and also for controlling contamination from radioactive waste in the environment is a challenging task

  4. Evaluation of laser diode thermal desorption-tandem mass spectrometry (LDTD-MS-MS) in forensic toxicology.

    Science.gov (United States)

    Bynum, Nichole D; Moore, Katherine N; Grabenauer, Megan

    2014-10-01

    Many forensic laboratories experience backlogs due to increased drug-related cases. Laser diode thermal desorption (LDTD) has demonstrated its applicability in other scientific areas by providing data comparable with instrumentation, such as liquid chromatography-tandem mass spectrometry, in less time. LDTD-MS-MS was used to validate 48 compounds in drug-free human urine and blood for screening or quantitative analysis. Carryover, interference, limit of detection, limit of quantitation, matrix effect, linearity, precision and accuracy and stability were evaluated. Quantitative analysis indicated that LDTD-MS-MS produced precise and accurate results with the average overall within-run precision in urine and blood represented by a %CV forensic toxicology but before it can be successfully implemented that there are some challenges that must be addressed. Although the advantages of the LDTD system include minimal maintenance and rapid analysis (∼10 s per sample) which makes it ideal for high-throughput forensic laboratories, a major disadvantage is its inability or difficulty analyzing isomers and isobars due to the lack of chromatography without the use of high-resolution MS; therefore, it would be best implemented as a screening technique. © The Author 2014. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  5. Gas chromatography-mass spectrometry (GC-MS) analysis of extractives of naturally durable wood

    Science.gov (United States)

    G.T. Kirker; A.B. Blodgett; S.T. Lebow; C.A. Clausen

    2011-01-01

    A preliminary study to evaluate naturally durable wood species in an above ground field trial using Gas Chromatography-Mass Spectrometry (GC-MS) detected differences in fatty acid extractives between species and within the same species over time. Fatty acids were extracted with chloroform: methanol mixture then methylated with sodium methoxide and fractionated using...

  6. microMS: A Python Platform for Image-Guided Mass Spectrometry Profiling

    Science.gov (United States)

    Comi, Troy J.; Neumann, Elizabeth K.; Do, Thanh D.; Sweedler, Jonathan V.

    2017-09-01

    Image-guided mass spectrometry (MS) profiling provides a facile framework for analyzing samples ranging from single cells to tissue sections. The fundamental workflow utilizes a whole-slide microscopy image to select targets of interest, determine their spatial locations, and subsequently perform MS analysis at those locations. Improving upon prior reported methodology, a software package was developed for working with microscopy images. microMS, for microscopy-guided mass spectrometry, allows the user to select and profile diverse samples using a variety of target patterns and mass analyzers. Written in Python, the program provides an intuitive graphical user interface to simplify image-guided MS for novice users. The class hierarchy of instrument interactions permits integration of new MS systems while retaining the feature-rich image analysis framework. microMS is a versatile platform for performing targeted profiling experiments using a series of mass spectrometers. The flexibility in mass analyzers greatly simplifies serial analyses of the same targets by different instruments. The current capabilities of microMS are presented, and its application for off-line analysis of single cells on three distinct instruments is demonstrated. The software has been made freely available for research purposes. [Figure not available: see fulltext.

  7. Formaldehyde measurements by Proton transfer reaction – Mass Spectrometry (PTR-MS: correction for humidity effects

    Directory of Open Access Journals (Sweden)

    A. Vlasenko

    2010-08-01

    Full Text Available Formaldehyde measurements can provide useful information about photochemical activity in ambient air, given that HCHO is formed via numerous oxidation processes. Proton transfer reaction mass spectrometry (PTR-MS is an online technique that allows measurement of VOCs at the sub-ppbv level with good time resolution. PTR-MS quantification of HCHO is hampered by the humidity dependence of the instrument sensitivity, with higher humidity leading to loss of PTR-MS signal. In this study we present an analytical, first principles approach to correct the PTR-MS HCHO signal according to the concentration of water vapor in sampled air. The results of the correction are validated by comparison of the PTR-MS results to those from a Hantzsch fluorescence monitor which does not have the same humidity dependence. Results are presented for an intercomparison made during a field campaign in rural Ontario at Environment Canada's Centre for Atmospheric Research Experiments.

  8. Open Access UHPSFC/MS - an additional analytical resource for an academic mass spectrometry facility.

    Science.gov (United States)

    Herniman, Julie M; Langley, G John

    2016-08-15

    Many compounds submitted for analysis in Chemistry at the University of Southampton do not retain, elute or ionize using open access reversed-phase ultra-high-performance liquid chromatography/mass spectrometry (RP-UHPLC/MS) and require analysis via infusion. An ultra-high-performance supercritical fluid chromatography mass spectrometry approach was implemented to afford high-throughput analysis of these compounds with chromatographic separation. A UPC(2) -TQD MS system has been incorporated into the open access MS provision within Chemistry at the University of Southampton, using an ESCi source (electrospray and atmospheric pressure chemical ionization) and an atmospheric pressure photoionization (APPI) source. Access to instrumentation is enabled via a web-based interface (RemoteAnalyzer™). Compounds such as fluorosugars, fullerenes, phosphoramidites, porphyrins, and rotaxanes exhibiting properties incompatible with RP-UHPLC/MS have been analyzed using automated chromatography and mass spectrometry methods. The speedy return of data enables research in these areas to progress unhindered by sample type. The provision of an electronic web format enables easy incorporation of chromatograms and mass spectra into electronic files and reports. The implementation of UHPSFC/MS increases access to a wide range of chemistries incompatible with reversed-phase chromatography and polar solvents, enabling more than 90% of submitted samples to be analyzed using an open access approach. Further, chromatographic separation is provided where previously flow injection or infusion analyses were the only options. Copyright © 2016 John Wiley & Sons, Ltd. Copyright © 2016 John Wiley & Sons, Ltd.

  9. Determination of 20 trace elements and arsenic species for a realgar-containing traditional Chinese medicine Niuhuang Jiedu tablets by direct inductively coupled plasma-mass spectrometry and high performance liquid chromatography-inductively coupled plasma-mass spectrometry.

    Science.gov (United States)

    Jin, Pengfei; Liang, Xiaoli; Xia, Lufeng; Jahouh, Farid; Wang, Rong; Kuang, Yongmei; Hu, Xin

    2016-01-01

    Niuhuang Jiedu tablet (NHJDT) is a realgar-containing traditional Chinese medicine. A direct inductively coupled plasma-mass spectrometry (ICP-MS) method for the simultaneous determination of 20 trace elements (Mg, K, Ca, Na, Fe, As, Zn, Sr, Ba, Cu, Mn, Ni, Pb, V, Cr, Se, Co, Mo, Cd, Hg) in NHJDT, as well as in water, gastric fluid and intestinal fluid was established. Meanwhile, a high performance liquid chromatography-inductively coupled plasma-mass spectrometry (HPLC-ICP-MS) method was developed for the determination of arsenite (As(III)), arsenate (As(V)), monomethylarsonic acid (MMA), dimethylarsinic acid (DMA) and for the identification of arsenobetaine (AsB) and arsenocholine (AsC) in these extracts. Both methods were fully validated in the respect of linearity, sensitivity, precision, stability and accuracy. The reliability of the ICP-MS method was further evaluated using a certified standard reference material prepared from dried tomato leaves (NIST, SRM 1572a). The analysis showed that some manufacturers formulated lower amount of realgar than required in the Chinese Pharmacopoeia (ChP) in their preparations. In addition, almost same extraction profiles for total As and inorganic As were found in water and in gastrointestinal fluids, while higher extraction rates for other 19 elements were observed in gastrointestinal fluids. Our findings show that the toxicities of Hg, Cu, Cd and Pb in NHJDP are low, while the real As toxicity in NHJDT should be deeply investigated. Copyright © 2015 Elsevier GmbH. All rights reserved.

  10. Integration of Electrochemistry with Ultra Performance Liquid Chromatography/Mass Spectrometry (UPLC/MS)

    Science.gov (United States)

    Cai, Yi; Zheng, Qiuling; Liu, Yong; Helmy, Roy; Loo, Joseph A.; Chen, Hao

    2015-01-01

    This study presents the development of ultra-performance liquid chromatography/mass spectrometry (UPLC/MS) combined with electrochemistry (EC) for the first time and its application for the structural analysis of disulfide bond-containing proteins/peptides. In our approach, a protein/peptide mixture sample undergoes fast UPLC separation and subsequent electrochemical reduction in an electrochemical flow cell followed by online MS and MS/MS analyses. The electrochemical cell is coupled to MS using our recently developed desorption electrospray ionization (DESI) interface. Using this UPLC/EC/DESI-MS method, disulfide bond-containing peptides can be differentiated from those without disulfide bonds as the former are electroactive and reducible. Tandem MS analysis of the disulfide-reduced peptide ions provides increased sequence and disulfide linkage pattern information. In a reactive DESI-MS detection experiment in which a supercharging reagent was used to dope the DESI spray solvent, increased charging was obtained for the UPLC-separated proteins. Strikingly, upon online electrolytic reduction, supercharged proteins (e.g., α-lactalbumin) showed even higher charging, which would be useful in top-down protein structure analysis as increased charges are known to promote protein ion dissociation. Also, the separation speed and sensitivity are enhanced by approximately 1~2 orders of magnitude by using UPLC for the LC/EC/MS platform, in comparison to the previously used high performance liquid chromatography (HPLC). This UPLC/EC/DESI-MS method combines the power of fast UPLC separation, fast electrochemical conversion and online MS structural analysis for a potentially valuable tool for proteomics research and bioanalysis. PMID:26307715

  11. Detection of Radiation-Exposure Biomarkers by Differential Mobility Prefiltered Mass Spectrometry (DMS-MS).

    Science.gov (United States)

    Coy, Stephen L; Krylov, Evgeny V; Schneider, Bradley B; Covey, Thomas R; Brenner, David J; Tyburski, John B; Patterson, Andrew D; Krausz, Kris W; Fornace, Albert J; Nazarov, Erkinjon G

    2010-04-15

    Technology to enable rapid screening for radiation exposure has been identified as an important need, and, as a part of a NIH / NIAD effort in this direction, metabolomic biomarkers for radiation exposure have been identified in a recent series of papers. To reduce the time necessary to detect and measure these biomarkers, differential mobility spectrometry - mass spectrometry (DMS-MS) systems have been developed and tested. Differential mobility ion filters preselect specific ions and also suppress chemical noise created in typical atmospheric-pressure ionization sources (ESI, MALDI, and others). Differential-mobility-based ion selection is based on the field dependence of ion mobility, which, in turn, depends on ion characteristics that include conformation, charge distribution, molecular polarizability, and other properties, and on the transport gas composition which can be modified to enhance resolution. DMS-MS is able to resolve small-molecule biomarkers from nearly-isobaric interferences, and suppresses chemical noise generated in the ion source and in the mass spectrometer, improving selectivity and quantitative accuracy. Our planar DMS design is rapid, operating in a few milliseconds, and analyzes ions before fragmentation. Depending on MS inlet conditions, DMS-selected ions can be dissociated in the MS inlet expansion, before mass analysis, providing a capability similar to MS/MS with simpler instrumentation. This report presents selected DMS-MS experimental results, including resolution of complex test mixtures of isobaric compounds, separation of charge states, separation of isobaric biomarkers (citrate and isocitrate), and separation of nearly-isobaric biomarker anions in direct analysis of a bio-fluid sample from the radiation-treated group of a mouse-model study. These uses of DMS combined with moderate resolution MS instrumentation indicate the feasibility of field-deployable instrumentation for biomarker evaluation.

  12. Applications of plasma spectrometry and high performance liquid chromatography in environmental and food science

    International Nuclear Information System (INIS)

    Iordache, Andreea-Maria; Biraruti, Elisabeta-Irina; Ionete, Roxana-Elena

    2008-01-01

    Full text: Plasma spectrometry has many applications in food science in analysis of a wide range of samples in the food chain. Food science in the broadest sense can be extended to include soil chemistry, plant uptake and, at the other end of the food chain, studies into the metabolic fate of particular elements or elemental species when the foods are consumed by humans or animals. Inductively Coupled Plasma Mass Spectrometry allows multi-element measurements of most elements in the periodic table. A very sensitive analytical technique for trace analysis of samples can be performed by inductively plasma mass spectrometer with quadrupolar detector using ultrasonic nebulization. High Performance Liquid Chromatography (HPLC) is an analytical technique for the separation and determination of organic and inorganic solutes in any samples especially biological, pharmaceutical, food, environmental. The present paper emphasizes that the future tendencies HPLC-ICP-MS is often the preferred analytical technique for these applications due to the simplicity of the coupling between the HPLC and ICP-MS Varian 820 using ultrasonic nebulization, potential for on-line separations with high species specificity and the capability for optimum limits of detection without the necessity of using complex hydride generation mechanisms. (authors)

  13. Matrix effect in the analysis of drugs of abuse from urine with desorption atmospheric pressure photoionization-mass spectrometry (DAPPI-MS) and desorption electrospray ionization-mass spectrometry (DESI-MS)

    International Nuclear Information System (INIS)

    Suni, Niina M.; Lindfors, Pia; Laine, Olli; Ostman, Pekka; Ojanperae, Ilkka; Kotiaho, Tapio; Kauppila, Tiina J.; Kostiainen, Risto

    2011-01-01

    Highlights: → DAPPI-MS and DESI-MSI in the analysis of drugs of abuse from urine. → DAPPI-MS has better urine matrix tolerance over DESI-MS. → Urine matrix can affect the ionization mechanism in DAPPI. → DAPPI-MS/MS can be used for screening of drugs from urine after sample pretreatment. - Abstract: We have studied the matrix effect within direct analysis of benzodiazepines and opioids from urine with desorption electrospray ionization-mass spectrometry (DESI-MS) and desorption atmospheric pressure photoionization-mass spectrometry (DAPPI-MS). The urine matrix was found to affect the ionization mechanism of the opioids in DAPPI-MS favoring proton transfer over charge exchange reaction. The sensitivity for the drugs in solvent matrix was at the same level with DESI-MS and DAPPI-MS (LODs 0.05-6 μg mL -1 ) but the decrease in sensitivity due to the urine matrix was higher with DESI (typically 20-160-fold) than with DAPPI (typically 2-15-fold) indicating better matrix tolerance of DAPPI over DESI. Also in MS/MS mode, DAPPI provided better sensitivity than DESI for the drugs in urine. The feasibility of DAPPI-MS/MS was then studied in screening the same drugs from five authentic, forensic post mortem urine samples. A reference measurement with gas chromatography-mass spectrometry (GC-MS) (including pretreatment) revealed 16 findings from the samples, whereas with DAPPI-MS/MS after sample pretreatment, 15 findings were made. Sample pretreatment was found necessary, since only eight findings were made from the same samples untreated.

  14. Matrix effect in the analysis of drugs of abuse from urine with desorption atmospheric pressure photoionization-mass spectrometry (DAPPI-MS) and desorption electrospray ionization-mass spectrometry (DESI-MS)

    Energy Technology Data Exchange (ETDEWEB)

    Suni, Niina M.; Lindfors, Pia; Laine, Olli [Division of Pharmaceutical Chemistry, University of Helsinki, P.O. Box 56, Helsinki FI-00014 (Finland); Ostman, Pekka; Ojanperae, Ilkka [Hjelt Institute, Department of Forensic Medicine, University of Helsinki, P.O. Box 40, Helsinki FI-00014 (Finland); Kotiaho, Tapio [Division of Pharmaceutical Chemistry, University of Helsinki, P.O. Box 56, Helsinki FI-00014 (Finland); Laboratory of Analytical Chemistry, Department of Chemistry, University of Helsinki, P.O. Box 55, Helsinki FI-00014 (Finland); Kauppila, Tiina J. [Division of Pharmaceutical Chemistry, University of Helsinki, P.O. Box 56, Helsinki FI-00014 (Finland); Kostiainen, Risto, E-mail: risto.kostiainen@helsinki.fi [Division of Pharmaceutical Chemistry, University of Helsinki, P.O. Box 56, Helsinki FI-00014 (Finland)

    2011-08-05

    Highlights: {yields} DAPPI-MS and DESI-MSI in the analysis of drugs of abuse from urine. {yields} DAPPI-MS has better urine matrix tolerance over DESI-MS. {yields} Urine matrix can affect the ionization mechanism in DAPPI. {yields} DAPPI-MS/MS can be used for screening of drugs from urine after sample pretreatment. - Abstract: We have studied the matrix effect within direct analysis of benzodiazepines and opioids from urine with desorption electrospray ionization-mass spectrometry (DESI-MS) and desorption atmospheric pressure photoionization-mass spectrometry (DAPPI-MS). The urine matrix was found to affect the ionization mechanism of the opioids in DAPPI-MS favoring proton transfer over charge exchange reaction. The sensitivity for the drugs in solvent matrix was at the same level with DESI-MS and DAPPI-MS (LODs 0.05-6 {mu}g mL{sup -1}) but the decrease in sensitivity due to the urine matrix was higher with DESI (typically 20-160-fold) than with DAPPI (typically 2-15-fold) indicating better matrix tolerance of DAPPI over DESI. Also in MS/MS mode, DAPPI provided better sensitivity than DESI for the drugs in urine. The feasibility of DAPPI-MS/MS was then studied in screening the same drugs from five authentic, forensic post mortem urine samples. A reference measurement with gas chromatography-mass spectrometry (GC-MS) (including pretreatment) revealed 16 findings from the samples, whereas with DAPPI-MS/MS after sample pretreatment, 15 findings were made. Sample pretreatment was found necessary, since only eight findings were made from the same samples untreated.

  15. Plutonium bioassay by inductively coupled plasma mass spectrometry ICP/MS

    International Nuclear Information System (INIS)

    Wyse, E.J.; Fisher, D.R.

    1993-04-01

    The determination of plutonium in urine poses several analytical challenges, e.g., detectability, matrix, etc. We have investigated the feasibility of analyzing plutonium in processed urine by inductively coupled plasma mass spectrometry (ICP/MS). The urine samples are first spiked with 244 Pu as a tracer and internal standard, then processed by co-precipitation and column chromatography using TRU-Spec trademark, an extraction resin. By enhancing ICP/MS detection capabilities via improved sample introduction and data acquisition efficiencies, an instrumental detection limit of 5 to 50 fg (0.3 to 3 fCi for 239 pu) is typically obtained, depending on the desired degree of quantitation. A brief summary of the analytical method as well as the basis for measuring radionuclides by ICP/MS are submitted; the separation procedure, methods of sample introduction, and data acquisition techniques are then highlighted

  16. Ms2lda.org: web-based topic modelling for substructure discovery in mass spectrometry.

    Science.gov (United States)

    Wandy, Joe; Zhu, Yunfeng; van der Hooft, Justin J J; Daly, Rónán; Barrett, Michael P; Rogers, Simon

    2017-09-14

    We recently published MS2LDA, a method for the decomposition of sets of molecular fragment data derived from large metabolomics experiments. To make the method more widely available to the community, here we present ms2lda.org, a web application that allows users to upload their data, run MS2LDA analyses and explore the results through interactive visualisations. Ms2lda.org takes tandem mass spectrometry data in many standard formats and allows the user to infer the sets of fragment and neutral loss features that co-occur together (Mass2Motifs). As an alternative workflow, the user can also decompose a dataset onto predefined Mass2Motifs. This is accomplished through the web interface or programmatically from our web service. The website can be found at http://ms2lda.org , while the source code is available at https://github.com/sdrogers/ms2ldaviz under the MIT license. Supplementary data are available at Bioinformatics online. © The Author(s) 2017. Published by Oxford University Press.

  17. Quantification of Hydroxychloroquine in Blood Using Turbulent Flow Liquid Chromatography-Tandem Mass Spectrometry (TFLC-MS/MS).

    Science.gov (United States)

    Chambliss, Allison B; Füzéry, Anna K; Clarke, William A

    2016-01-01

    Hydroxychloroquine (HQ) is used routinely in the treatment of autoimmune disorders such as rheumatoid arthritis and lupus erythematosus. Issues such as marked pharmacokinetic variability and patient non-compliance make therapeutic drug monitoring of HQ a useful tool for management of patients taking this drug. Quantitative measurements of HQ may aid in identifying poor efficacy as well as provide reliable information to distinguish patient non-compliance from refractory disease. We describe a rapid 7-min assay for the accurate and precise measurement of HQ concentrations in 100 μL samples of human blood using turbulent flow liquid chromatography coupled to tandem mass spectrometry. HQ is isolated from EDTA whole blood after a simple extraction with its deuterated analog, hydroxychloroquine-d4, in 0.33 M perchloric acid. Samples are then centrifuged and injected onto the TFLC-MS/MS system. Quantification is performed using a nine-point calibration curve that is linear over a wide range (15.7-4000 ng/mL) with precisions of <5 %.

  18. Chiral liquid chromatography-mass spectrometry (LC-MS/MS) method development for the detection of salbutamol in urine samples.

    Science.gov (United States)

    Chan, Sue Hay; Lee, Warren; Asmawi, Mohd Zaini; Tan, Soo Choon

    2016-07-01

    A sequential solid-phase extraction (SPE) method was developed and validated using liquid chromatography-electrospray ionization tandem mass spectrometry (LC-ESI-MS/MS) for the detection and quantification of salbutamol enantiomers in porcine urine. Porcine urine samples were hydrolysed with β-glucuronidase/arylsulfatase from Helix pomatia and then subjected to a double solid-phase extraction (SPE) first using the Abs-Elut Nexus SPE and then followed by the Bond Elut Phenylboronic Acid (PBA) SPE. The salbutamol enantiomers were separated using the Astec CHIROBIOTIC™ T HPLC column (3.0mm×100mm; 5μm) maintained at 15°C with a 15min isocratic run at a flow rate of 0.4mL/min. The mobile phase constituted of 5mM ammonium formate in methanol. Salbutamol and salbutamol-tert-butyl-d9 (internal standard, IS) was monitored and quantified with the multiple reaction monitoring (MRM) mode. The method showed good linearity for the range of 0.1-10ng/mL with limit of quantification at 0.3ng/mL. Analysis of the QC samples showed intra- and inter-assay precisions to be less than 5.04%, and recovery ranging from 83.82 to 102.33%. Copyright © 2016 Elsevier B.V. All rights reserved.

  19. A Liquid Chromatography-Quadrupole-Time of Flight Mass Spectrometry (LC-Q-TOF MS) Study for Analyzing 35 Corticosteroid Compounds: Elucidation of MS/MS Fragmentation Pathways

    International Nuclear Information System (INIS)

    Noh, Eunyoung; Yoon, Chang-Yong; Lee, Ji Hyun; Baek, Sun-Young; Do, Jung-Ah; Lee, Jung-min; Oh, Han Bin

    2016-01-01

    Corticosteroids have been often found to be added to a dietary supplement for the purpose of illegally improving the effect of their products. Thus, it is imperative to develop or improve a method that enables one to rapidly and reliably analyze corticosteroids in health or dietary supplements, for the safety management purpose. In the present study, results from liquid chromatography-quadrupole time-of-flight mass spectrometry (LC-Q-TOF-MS) experiments for the selected 35 corticosteroid compounds are presented, which can be useful for the qualitative screening of corticosteroids in health or dietary supplements. Specifically, retention times, accurate mass data of the protonated steroids, m/z values of major fragment ions are given for the 35 corticosteroids. Further, fragmentation pathways for the selected steroids are also suggested. Based on the suggested fragmentation pathways, it was shown that an unknown steroid compound can be readily identified using the knowledge of a group of unique and specific common skeletal fragments. The high selectivity and sensitivity of the LC-Q-TOF-MS/MS results combined with the knowledge of the fragmentation pathways can offer a new opportunity for rapid and accurate screening of corticosteroids, thus preventing health-related incidents involving adulterated products and clamping down on illegally circulated health products.

  20. A Liquid Chromatography-Quadrupole-Time of Flight Mass Spectrometry (LC-Q-TOF MS) Study for Analyzing 35 Corticosteroid Compounds: Elucidation of MS/MS Fragmentation Pathways

    Energy Technology Data Exchange (ETDEWEB)

    Noh, Eunyoung; Yoon, Chang-Yong; Lee, Ji Hyun; Baek, Sun-Young; Do, Jung-Ah [Ministry of Food and Drug Safety, Cheongju (Korea, Republic of); Lee, Jung-min; Oh, Han Bin [Sogang University, Seoul (Korea, Republic of)

    2016-07-15

    Corticosteroids have been often found to be added to a dietary supplement for the purpose of illegally improving the effect of their products. Thus, it is imperative to develop or improve a method that enables one to rapidly and reliably analyze corticosteroids in health or dietary supplements, for the safety management purpose. In the present study, results from liquid chromatography-quadrupole time-of-flight mass spectrometry (LC-Q-TOF-MS) experiments for the selected 35 corticosteroid compounds are presented, which can be useful for the qualitative screening of corticosteroids in health or dietary supplements. Specifically, retention times, accurate mass data of the protonated steroids, m/z values of major fragment ions are given for the 35 corticosteroids. Further, fragmentation pathways for the selected steroids are also suggested. Based on the suggested fragmentation pathways, it was shown that an unknown steroid compound can be readily identified using the knowledge of a group of unique and specific common skeletal fragments. The high selectivity and sensitivity of the LC-Q-TOF-MS/MS results combined with the knowledge of the fragmentation pathways can offer a new opportunity for rapid and accurate screening of corticosteroids, thus preventing health-related incidents involving adulterated products and clamping down on illegally circulated health products.

  1. Determination of {sup 126}Sn half-life from ICP-MS and gamma spectrometry measurements

    Energy Technology Data Exchange (ETDEWEB)

    Bienvenu, P.; Arnal, N.; Comte, J. [CEA Cadarache DEN/DEC/SA3C/LARC, Paul Lez Durance (France); Ferreux, L.; Lepy, M.C.; Be, M.M. [CEA Saclay LIST LNE/LNHB, Gif sur Yvette (France); Andreoletti, G. [AREVA Cogema SL/UP2-800, Beaumont Hague (France)

    2009-07-01

    A new value of {sup 126}Sn half-life was determined by combination of inductively coupled plasma-mass spectrometry (ICP-MS) and gamma spectrometry measurements on purified sample solutions collected from nuclear fuel reprocessing. {sup 126}Sn was isolated through dissolution of fission product precipitates and liquid-liquid extraction with N-benzoyl-N-phenyl-hydroxylamine (BPHA). The abundance of {sup 126}Sn atoms together with the absence of interfering species in the analysed solutions made it possible to measure both mass concentration and nuclide activity with high precision and accuracy. This led to a {sup 126}Sn half-life value of 1.980 (57) x 10{sup 5} a. (orig.)

  2. Separation of different ion structures in atmospheric pressure photoionization-ion mobility spectrometry-mass spectrometry (APPI-IMS-MS).

    Science.gov (United States)

    Laakia, Jaakko; Adamov, Alexey; Jussila, Matti; Pedersen, Christian S; Sysoev, Alexey A; Kotiaho, Tapio

    2010-09-01

    This study demonstrates how positive ion atmospheric pressure photoionization-ion mobility spectrometry-mass spectrometry (APPI-IMS-MS) can be used to produce different ionic forms of an analyte and how these can be separated. When hexane:toluene (9:1) is used as a solvent, 2,6-di-tert-butylpyridine (2,6-DtBPyr) and 2,6-di-tert-4-methylpyridine (2,6-DtB-4-MPyr) efficiently produce radical cations [M](+*) and protonated [M + H](+) molecules, whereas, when the sample solvent is hexane, protonated molecules are mainly formed. Interestingly, radical cations drift slower in the drift tube than the protonated molecules. It was observed that an oxygen adduct ion, [M + O(2)](+*), which was clearly seen in the mass spectra for hexane:toluene (9:1) solutions, shares the same mobility with radical cations, [M](+*). Therefore, the observed mobility order is most likely explained by oxygen adduct formation, i.e., the radical cation forming a heavier adduct. For pyridine and 2-tert-butylpyridine, only protonated molecules could be efficiently formed in the conditions used. For 1- and 2-naphthol it was observed that in hexane the protonated molecule typically had a higher intensity than the radical cation, whereas in hexane:toluene (9:1) the radical cation [M](+*) typically had a higher intensity than the protonated molecule [M + H](+). Interestingly, the latter drifts slower than the radical cation [M](+*), which is the opposite of the drift pattern seen for 2,6-DtBPyr and 2,6-DtB-4-MPyr. 2010 American Society for Mass Spectrometry. Published by Elsevier Inc. All rights reserved.

  3. High performance liquid chromatography hyphenated to inductively coupled plasma mass spectrometry for V and Ni quantification as tetrapyrroles

    Science.gov (United States)

    Duyck, Christiane Béatrice; Saint'Pierre, Tatiana Dillenburg; Miekeley, Norbert; da Fonseca, Teresa Cristina Oliveira; Szatmari, Peter

    2011-05-01

    A method was developed for the determination of V and Ni as tetrapyrroles by High Performance Liquid Chromatography hyphenated to Inductively Coupled Plasma Mass Spectrometry (HPLC-ICP-MS) using reversed phase and elution gradient. Chlorinated solvents and tetrahydrofuran were investigated as regard to separation time and ICP-MS detection efficiencies. The final elution gradient program started from pure methanol to a mixture of 20:80 (v/v) chloroform:methanol. External quantification of V and Ni with inorganic standards by flow injection ICP-MS, used online with HPLC, resulted in 95% of recoveries. The Limits of Detection for V during methanol elution and for Ni during the 20% chloroform gradient elution were evaluated by their minimum detectable concentrations, which were, respectively, 5 μg L - 1 and 8 μg L - 1 . The methodology was applied to polar and resin fractions separated from a Brazilian crude oil and a sediment extract from an oil-polluted area in the Guanabara Bay, Rio de Janeiro, Brazil. Vanadium as tetrapyrroles represented the totality of V content in the polar fraction, whereas Ni was in different polar forms in the resin and sediment extract.

  4. Analysis of trace gases at ppb levels by proton transfer reaction mass spectrometry (PTR-MS)

    International Nuclear Information System (INIS)

    Lindinger, W.; Hansel, A.

    1996-01-01

    A proton transfer reaction mass spectrometry (PTR-MS) system has been developed which allows for on-line measurements of trace gas components with concentrations as low as 1 ppb. The method is based on reactions of H 3 O + ions, which perform non-dissociative proton transfer to most of the common organic trace constituents but do not react with any of the components present in clean air. Examples of medical information obtained by means of breath analysis, of environmental trace analysis, and examples in the field of food chemistry demonstrate the wide applicability of the method. (Authors)

  5. High-throughput screening and confirmation of 22 banned veterinary drugs in feedstuffs using LC-MS/MS and high-resolution Orbitrap mass spectrometry.

    Science.gov (United States)

    Wang, Xufeng; Liu, Yanghong; Su, Yijuan; Yang, Jianwen; Bian, Kui; Wang, Zongnan; He, Li-Min

    2014-01-15

    A new analytical strategy based on liquid chromatography-tandem mass spectrometry (LC-MS/MS) combined with accurate mass high-resolution Orbitrap mass spectrometry (HR-Orbitrap MS) was performed for high-throughput screening, confirmation, and quantification of 22 banned or unauthorized veterinary drugs in feedstuffs according to Bulletin 235 of the Ministry of Agriculture, China. Feed samples were extracted with acidified acetonitrile, followed by cleanup using solid-phase extraction cartridge. The extracts were first screened by LC-MS/MS in a single selected reaction monitoring mode. The suspected positive samples were subjected to a specific pretreatment for confirmation and quantification of analyte of interest with LC-MS/MS and HR-Orbitrap MS. Mean recoveries for all target analytes (except for carbofuran and chlordimeform, which were about 35 and 45%, respectively) ranged from 52.2 to 90.4%, and the relative standard deviations were screening of real samples obtained from local feed markets and confirmation of the suspected target analytes. It provides a high-throughput, sensitive, and reliable screening, identification, and quantification of banned veterinary drugs in routine monitoring programs of feedstuffs.

  6. Exploring surface photoreaction dynamics using pixel imaging mass spectrometry (PImMS)

    Science.gov (United States)

    Kershis, Matthew D.; Wilson, Daniel P.; White, Michael G.; John, Jaya John; Nomerotski, Andrei; Brouard, Mark; Lee, Jason W. L.; Vallance, Claire; Turchetta, Renato

    2013-08-01

    A new technique for studying surface photochemistry has been developed using an ion imaging time-of-flight mass spectrometer in conjunction with a fast camera capable of multimass imaging. This technique, called pixel imaging mass spectrometry (PImMS), has been applied to the study of butanone photooxidation on TiO2(110). In agreement with previous studies of this system, it was observed that the main photooxidation pathway for butanone involves ejection of an ethyl radical into vacuum which, as confirmed by our imaging experiment, undergoes fragmentation after ionization in the mass spectrometer. This proof-of-principle experiment illustrates the usefulness and applicability of PImMS technology to problems of interest within the surface science community.

  7. Quantification of methionine and selenomethionine in biological samples using multiple reaction monitoring high performance liquid chromatography tandem mass spectrometry (MRM-HPLC-MS/MS).

    Science.gov (United States)

    Vu, Dai Long; Ranglová, Karolína; Hájek, Jan; Hrouzek, Pavel

    2018-05-01

    Quantification of selenated amino-acids currently relies on methods employing inductively coupled plasma mass spectrometry (ICP-MS). Although very accurate, these methods do not allow the simultaneous determination of standard amino-acids, hampering the comparison of the content of selenated versus non-selenated species such as methionine (Met) and selenomethionine (SeMet). This paper reports two approaches for the simultaneous quantification of Met and SeMet. In the first approach, standard enzymatic hydrolysis employing Protease XIV was applied for the preparation of samples. The second approach utilized methanesulfonic acid (MA) for the hydrolysis of samples, either in a reflux system or in a microwave oven, followed by derivatization with diethyl ethoxymethylenemalonate. The prepared samples were then analyzed by multiple reaction monitoring high performance liquid chromatography tandem mass spectrometry (MRM-HPLC-MS/MS). Both approaches provided platforms for the accurate determination of selenium/sulfur substitution rate in Met. Moreover the second approach also provided accurate simultaneous quantification of Met and SeMet with a low limit of detection, low limit of quantification and wide linearity range, comparable to the commonly used gas chromatography mass spectrometry (GC-MS) method or ICP-MS. The novel method was validated using certified reference material in conjunction with the GC-MS reference method. Copyright © 2018. Published by Elsevier B.V.

  8. Monoacylglycerol Analysis Using MS/MSALL Quadruple Time of Flight Mass Spectrometry

    Directory of Open Access Journals (Sweden)

    Fei Gao

    2016-08-01

    Full Text Available Monoacylglycerols (MAGs are structural and bioactive metabolites critical for biological function. Development of facile tools for measuring MAG are essential to understand its role in different diseases and various pathways. A data-independent acquisition method, MS/MSALL, using electrospray ionization (ESI coupled quadrupole time of flight mass spectrometry (MS, was utilized for the structural identification and quantitative analysis of individual MAG molecular species. Compared with other acylglycerols, diacylglycerols (DAG and triacylglycerols (TAG, MAG characteristically presented as a dominant protonated ion, [M + H]+, and under low collision energy as fatty acid-like fragments due to the neutral loss of the glycerol head group. At low concentrations (<10 pmol/µL, where lipid-lipid interactions are rare, there was a strong linear correlation between ion abundance and MAG concentration. Moreover, using the MS/MSALL method the major MAG species from human plasma and mouse brown and white adipose tissues were quantified in less than 6 min. Collectively, these results demonstrate that MS/MSALL analysis of MAG is an enabling strategy for the direct identification and quantitative analysis of low level MAG species from biological samples with high throughput and sensitivity.

  9. phpMs: A PHP-Based Mass Spectrometry Utilities Library.

    Science.gov (United States)

    Collins, Andrew; Jones, Andrew R

    2018-03-02

    The recent establishment of cloud computing, high-throughput networking, and more versatile web standards and browsers has led to a renewed interest in web-based applications. While traditionally big data has been the domain of optimized desktop and server applications, it is now possible to store vast amounts of data and perform the necessary calculations offsite in cloud storage and computing providers, with the results visualized in a high-quality cross-platform interface via a web browser. There are number of emerging platforms for cloud-based mass spectrometry data analysis; however, there is limited pre-existing code accessible to web developers, especially for those that are constrained to a shared hosting environment where Java and C applications are often forbidden from use by the hosting provider. To remedy this, we provide an open-source mass spectrometry library for one of the most commonly used web development languages, PHP. Our new library, phpMs, provides objects for storing and manipulating spectra and identification data as well as utilities for file reading, file writing, calculations, peptide fragmentation, and protein digestion as well as a software interface for controlling search engines. We provide a working demonstration of some of the capabilities at http://pgb.liv.ac.uk/phpMs .

  10. {sup 99}Tc bioassay by inductively coupled plasma mass spectrometry (ICP-MS)

    Energy Technology Data Exchange (ETDEWEB)

    Lewis, L.A.

    1998-05-01

    A means of analyzing {sup 99}Tc in urine by inductively coupled plasma mass spectrometry (ICP-MS) has been developed. Historically, {sup 99}Tc analysis was based on the radiometric detection of the 293 keV E{sub Max} beta decay product by liquid scintillation or gas flow proportional counting. In a urine matrix, the analysis of{sup 99}Tc is plagued with many difficulties using conventional radiometric methods. Difficulties originate during chemical separation due to the volatile nature of Tc{sub 2}O{sub 7} or during radiation detection due to color or chemical quenching. A separation scheme for {sup 99}Tc detection by ICP-MS is given and is proven to be a sensitive and robust analytical alternative. A comparison of methods using radiometric and mass quantitation of {sup 99}Tc has been conducted in water, artificial urine, and real urine matrices at activity levels between 700 and 2,200 dpm/L. Liquid scintillation results based on an external standard quench correction and a quench curve correction method are compared to results obtained by ICP-MS. Each method produced accurate results, however the precision of the ICP-MS results is superior to that of liquid scintillation results. Limits of detection (LOD) for ICP-MS and liquid scintillation detection are 14.67 and 203.4 dpm/L, respectively, in a real urine matrix. In order to determine the basis for the increased precision of the ICP-MS results, the detection sensitivity for each method is derived and measured. The detection sensitivity for the {sup 99}Tc isotope by ICP-MS is 2.175 x 10{sup {minus}7} {+-} 8.990 x 10{sup {minus}9} and by liquid scintillation is 7.434 x 10{sup {minus}14} {+-} 7.461 x 10{sup {minus}15}. A difference by seven orders of magnitude between the two detection systems allows ICP-MS samples to be analyzed for a period of 15 s compared to 3,600 s by liquid scintillation counting with a lower LOD.

  11. Triple Quadrupole Versus High Resolution Quadrupole-Time-of-Flight Mass Spectrometry for Quantitative LC-MS/MS Analysis of 25-Hydroxyvitamin D in Human Serum

    Science.gov (United States)

    Geib, Timon; Sleno, Lekha; Hall, Rabea A.; Stokes, Caroline S.; Volmer, Dietrich A.

    2016-08-01

    We describe a systematic comparison of high and low resolution LC-MS/MS assays for quantification of 25-hydroxyvitamin D3 in human serum. Identical sample preparation, chromatography separations, electrospray ionization sources, precursor ion selection, and ion activation were used; the two assays differed only in the implemented final mass analyzer stage; viz. high resolution quadrupole-quadrupole-time-of-flight (QqTOF) versus low resolution triple quadrupole instruments. The results were assessed against measured concentration levels from a routine clinical chemiluminescence immunoassay. Isobaric interferences prevented the simple use of TOF-MS spectra for extraction of accurate masses and necessitated the application of collision-induced dissociation on the QqTOF platform. The two mass spectrometry assays provided very similar analytical figures of merit, reflecting the lack of relevant isobaric interferences in the MS/MS domain, and were successfully applied to determine the levels of 25-hydroxyvitamin D for patients with chronic liver disease.

  12. PyMS: a Python toolkit for processing of gas chromatography-mass spectrometry (GC-MS data. Application and comparative study of selected tools

    Directory of Open Access Journals (Sweden)

    O'Callaghan Sean

    2012-05-01

    Full Text Available Abstract Background Gas chromatography–mass spectrometry (GC-MS is a technique frequently used in targeted and non-targeted measurements of metabolites. Most existing software tools for processing of raw instrument GC-MS data tightly integrate data processing methods with graphical user interface facilitating interactive data processing. While interactive processing remains critically important in GC-MS applications, high-throughput studies increasingly dictate the need for command line tools, suitable for scripting of high-throughput, customized processing pipelines. Results PyMS comprises a library of functions for processing of instrument GC-MS data developed in Python. PyMS currently provides a complete set of GC-MS processing functions, including reading of standard data formats (ANDI- MS/NetCDF and JCAMP-DX, noise smoothing, baseline correction, peak detection, peak deconvolution, peak integration, and peak alignment by dynamic programming. A novel common ion single quantitation algorithm allows automated, accurate quantitation of GC-MS electron impact (EI fragmentation spectra when a large number of experiments are being analyzed. PyMS implements parallel processing for by-row and by-column data processing tasks based on Message Passing Interface (MPI, allowing processing to scale on multiple CPUs in distributed computing environments. A set of specifically designed experiments was performed in-house and used to comparatively evaluate the performance of PyMS and three widely used software packages for GC-MS data processing (AMDIS, AnalyzerPro, and XCMS. Conclusions PyMS is a novel software package for the processing of raw GC-MS data, particularly suitable for scripting of customized processing pipelines and for data processing in batch mode. PyMS provides limited graphical capabilities and can be used both for routine data processing and interactive/exploratory data analysis. In real-life GC-MS data processing scenarios PyMS performs

  13. Analysis of metallic nanoparticles and their ionic counterparts in complex matrix by reversed-phase liquid chromatography coupled to ICP-MS.

    Science.gov (United States)

    Yang, Yuan; Luo, Li; Li, Hai-Pu; Wang, Qiang; Yang, Zhao-Guang; Qu, Zhi-Peng; Ding, Ru

    2018-05-15

    Developing quantification and characterization methodology for metallic nanoparticles (MNPs) and their ionic component in complex matrix are crucial for the evaluation of their environmental behavior and health risks to humans. In this study, reversed phase high performance liquid chromatography combined ICP-MS was established for the characterization of MNPs in complex matrix. The ionic component could be separated from NPs with the optimized parameters of aqueous mobile phase. Good linear relationship between average diameter and retention time of NPs was obtained using HPLC-ICP-MS and the size smaller than 40 nm could be determined with this method, the detected results were in accordance with TEM results. The low detection limit of AuNPs and Au(Ⅲ) (both in sub-μg/L level) showed that this method was promising for the characterization of AuNPs and Au(Ⅲ) in environmental water. The mass concentration of ionic Au(Ⅲ) in environmental water could be detected using the proposed HPLC-ICP-MS and the concentration of AuNPs was obtained by subtracting the Au(Ⅲ) concentration from the total Au (The concentration of total Au was detected by ICP-MS after microwave digestion). Furthermore this proposed HPLC-ICP-MS method and single particle-ICPMS (SP-ICP-MS) was used for the analysis of the Ag speciation in commercial antibacterial products. Copyright © 2018 Elsevier B.V. All rights reserved.

  14. Mass spectrometry of rhenium complexes: a comparative study by using LDI-MS, MALDI-MS, PESI-MS and ESI-MS.

    Science.gov (United States)

    Petroselli, Gabriela; Mandal, Mridul Kanti; Chen, Lee Chuin; Ruiz, Gustavo T; Wolcan, Ezequiel; Hiraoka, Kenzo; Nonami, Hiroshi; Erra-Balsells, Rosa

    2012-03-01

    A group of rhenium (I) complexes including in their structure ligands such as CF(3)SO(3)-, CH(3)CO(2)-, CO, 2,2'-bipyridine, dipyridil[3,2-a:2'3'-c]phenazine, naphthalene-2-carboxylate, anthracene-9-carboxylate, pyrene-1-carboxylate and 1,10-phenanthroline have been studied for the first time by mass spectrometry. The probe electrospray ionization (PESI) is a technique based on electrospray ionization (ESI) that generates electrospray from the tip of a solid metal needle. In this work, mass spectra for organometallic complexes obtained by PESI were compared with those obtained by classical ESI and high flow rate electrospray ionization assisted by corona discharge (HF-ESI-CD), an ideal method to avoid decomposition of the complexes and to induce their oxidation to yield intact molecular cation radicals in gas state [M](+·) and to produce their reduction yielding the gas species [M](-·). It was found that both techniques showed in general the intact molecular ions of the organometallics studied and provided additional structure characteristic diagnostic fragments. As the rhenium complexes studied in the present work showed strong absorption in the UV-visible region, particularly at 355 nm, laser desorption ionization (LDI) mass spectrometry experiments could be conducted. Although intact molecular ions could be detected in a few cases, LDI mass spectra showed diagnostic fragments for characterization of the complexes structure. Furthermore, matrix-assisted laser desorption ionization (MALDI) mass spectra were obtained. Nor-harmane, a compound with basic character, was used as matrix, and the intact molecular ions were detected in two examples, in negative ion mode as the [M](-·) species. Results obtained with 2-[(2E)-3-(4-tert-buthylphenyl)-2-methylprop-2-enylidene] malononitrile (DCTB) as matrix are also described. LDI experiments provided more information about the rhenium complex structures than did the MALDI ones. Copyright © 2012 John Wiley & Sons, Ltd.

  15. [Evaluation of mass spectrometry: MALDI-TOF MS for fast and reliable yeast identification].

    Science.gov (United States)

    Relloso, María S; Nievas, Jimena; Fares Taie, Santiago; Farquharson, Victoria; Mujica, María T; Romano, Vanesa; Zarate, Mariela S; Smayevsky, Jorgelina

    2015-01-01

    The matrix-assisted laser desorption/ionization time-of-flight mass spectrometry technique known as MALDI-TOF MS is a tool used for the identification of clinical pathogens by generating a protein spectrum that is unique for a given species. In this study we assessed the identification of clinical yeast isolates by MALDI-TOF MS in a university hospital from Argentina and compared two procedures for protein extraction: a rapid method and a procedure based on the manufacturer's recommendations. A short protein extraction procedure was applied in 100 isolates and the rate of correct identification at genus and species level was 98.0%. In addition, we analyzed 201 isolates, previously identified by conventional methods, using the methodology recommended by the manufacturer and there was 95.38% coincidence in the identification at species level. MALDI TOF MS showed to be a fast, simple and reliable tool for yeast identification. Copyright © 2014 Asociación Argentina de Microbiología. Publicado por Elsevier España, S.L.U. All rights reserved.

  16. Investigation of mercury-containing proteins by enriched stable isotopic tracer and size-exclusion chromatography hyphenated to inductively coupled plasma-isotope dilution mass spectrometry

    International Nuclear Information System (INIS)

    Shi Junwen; Feng Weiyue; Wang Meng; Zhang Fang; Li Bai; Wang Bing; Zhu Motao; Chai Zhifang

    2007-01-01

    In order to investigate trace mercury-containing proteins in maternal rat and their offspring, a method of enriched stable isotopic tracer ( 196 Hg and 198 Hg) combined with size-exclusion chromatography (SEC) coupled to inductively coupled plasma-isotope dilution mass spectrometry (ICP-IDMS) was developed. Prior to the analysis, 196 Hg- and 198 Hg-enriched methylmercury was administrated to the pregnant rats. Then the mercury-containing proteins in serum and brain cytosol of the dam and pup rats were separated by size-exclusion columns and the mercury was detected by ICP-MS. The ICP-MS spectrogram of the tracing samples showed significantly elevated 196 Hg and 198 Hg isotopic signals compared with the natural ones, indicating that the detection sensitivity could be increased by the tracer method. The contents of mercury in chromatographic fractions of the dam and pup rat brain cytosol were quantitatively estimated by post-column reverse ID-ICP-MS. The quantitative speciation differences of mercury in brain cytosol between the dam and pup rats were observed, indicating that such studies could be useful for toxicological estimation. Additionally, the isotopic ratio measurement of 198 Hg/ 202 Hg in the tracing samples could be used to identify the artifact mercury species caused in the analytical procedure. The study demonstrates that the tracer method combined with high-performance liquid chromatography (HPLC)-ICP-IDMS could provide reliably qualitative and quantitative information on mercury-containing proteins in organisms

  17. Liquid-chromatography mass spectrometry (LC-MS) of steroid hormone metabolites and its applications

    Science.gov (United States)

    Penning, Trevor M.; Lee, Seon-Hwa; Jin, Yi; Gutierrez, Alejandro; Blair, Ian A.

    2010-01-01

    Advances in liquid chromatography-mass spectrometry (LC-MS) can be used to measure steroid hormone metabolites in vitro and in vivo. We find that LC-Electrospray Ionization (ESI)-MS using a LCQ ion trap mass spectrometer in the negative ion mode can be used to monitor the product profile that results from 5α–dihydrotestosterone(DHT)-17β-glucuronide, DHT-17β-sulfate, and tibolone-17β-sulfate reduction catalyzed by human members of the aldo-keto reductase (AKR) 1C subfamily and assign kinetic constants to these reactions. We also developed a stable-isotope dilution LC-electron capture atmospheric pressure chemical ionization (ECAPCI)-MS method for the quantitative analysis of estrone (E1) and its metabolites as pentafluorobenzyl (PFB) derivatives in human plasma in the attomole range. The limit of detection for E1-PFB was 740 attomole on column. Separations can be performed using normal-phase LC because ionization takes place in the gas phase rather than in solution. This permits efficient separation of the regioisomeric 2- and 4-methoxy-E1. The method was validated for the simultaneous analysis of plasma E2 and its metabolites: 2-methoxy-E2, 4-methoxy-E2, 16α-hydroxy-E2, estrone (E1), 2-methoxy-E1, 4-methoxy-EI, and 16α-hydroxy-E1 from 5 pg/mL to 2,000 pg/mL. Our LC-MS methods have sufficient sensitivity to detect steroid hormone levels in prostate and breast tumors and should aid their molecular diagnosis and treatment. PMID:20083198

  18. Chemical profile of mango (Mangifera indica L.) using electrospray ionisation mass spectrometry (ESI-MS).

    Science.gov (United States)

    Oliveira, Bruno G; Costa, Helber B; Ventura, José A; Kondratyuk, Tamara P; Barroso, Maria E S; Correia, Radigya M; Pimentel, Elisângela F; Pinto, Fernanda E; Endringer, Denise C; Romão, Wanderson

    2016-08-01

    Mangifera indica L., mango fruit, is consumed as a dietary supplement with purported health benefits; it is widely used in the food industry. Herein, the chemical profile of the Ubá mango at four distinct maturation stages was evaluated during the process of growth and maturity using negative-ion mode electrospray ionisation Fourier transform ion cyclotron resonance mass spectrometry (ESI(-)FT-ICR MS) and physicochemical characterisation analysis (total titratable acidity (TA), total soluble solids (TSS), TSS/TA ratio, and total polyphenolic content). Primary (organic acids and sugars) and secondary metabolites (polyphenolic compounds) were mostly identified in the third maturation stage, thus indicating the best stage for harvesting and consuming the fruit. In addition, the potential cancer chemoprevention of the secondary metabolites (phenolic extracts obtained from mango samples) was evaluated using the induction of quinone reductase activity, concluding that fruit polyphenols have the potential for cancer chemoprevention. Copyright © 2016 Elsevier Ltd. All rights reserved.

  19. Uranium isotopes determination in urine samples using alpha spectrometry and ICP-MS

    Energy Technology Data Exchange (ETDEWEB)

    Rosa, Mychelle M.L.; Maihara, Vera A. [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil); Tine, Fernanda D.; Santos, Sandra M.C.; Bonifacio, Rodrigo L.; Taddei, Maria HelenaT. [Comissao Nacional de Energia Nuclear (LAPOC/CNEN-MG), Pocos de Caldas, MG (Brazil). Laboratorio de Pocos de Caldas

    2015-07-01

    The action of determining the concentration of uranium isotopes in biological samples, 'in vitro' bioassay, is an indirect method for evaluating the incorporation and quantification of these radionuclides internally deposited. When incorporated, these radionuclides tend to be disposed through excretion, with urine being the main source of data because it can be easily collected and analyzed. The most widely used methods for determination of uranium isotopes ({sup 234}U, {sup 235}U and {sup 238}U) are Alpha Spectrometry and ICP-MS. This work presents a comparative study for the determination of uranium isotopes using these two methodologies in real samples from occupationally exposed workers. In order to validate the methodology, a sample of the intercomparison exercise organized by PROCORAD (Association pour la Promotion du Controle de Qualite des Analyses de Biologie Medicale em Radiotoxicologie) was used, and the results were statistically compared applying the Student's t-test. (author)

  20. Uranium isotopes determination in urine samples using alpha spectrometry and ICP-MS

    International Nuclear Information System (INIS)

    Rosa, Mychelle M.L.; Maihara, Vera A.; Tine, Fernanda D.; Santos, Sandra M.C.; Bonifacio, Rodrigo L.; Taddei, Maria HelenaT.

    2015-01-01

    The action of determining the concentration of uranium isotopes in biological samples, 'in vitro' bioassay, is an indirect method for evaluating the incorporation and quantification of these radionuclides internally deposited. When incorporated, these radionuclides tend to be disposed through excretion, with urine being the main source of data because it can be easily collected and analyzed. The most widely used methods for determination of uranium isotopes ( 234 U, 235 U and 238 U) are Alpha Spectrometry and ICP-MS. This work presents a comparative study for the determination of uranium isotopes using these two methodologies in real samples from occupationally exposed workers. In order to validate the methodology, a sample of the intercomparison exercise organized by PROCORAD (Association pour la Promotion du Controle de Qualite des Analyses de Biologie Medicale em Radiotoxicologie) was used, and the results were statistically compared applying the Student's t-test. (author)

  1. Determination of rare earth elements by liquid chromatography/inductively coupled plasma atomic emission spectrometry

    International Nuclear Information System (INIS)

    Yoshida, K.; Haraguchi, H.

    1984-01-01

    Inductively coupled plasma atomic emission spectrometry (ICP-AES) interfaced with high-performance liquid chromatography (HPLC) has been applied to the determination of rare earth elements. ICP-AES was used as an element-selective detector for HPLC. The separation of rare earth elements with HPLC helped to avoid erroneous analytical results due to spectral interferences. Fifteen rare earth elements (Y and 14 lanthanides) were determined selectively with the HPLC/ICP-AES system using a concentration gradient method. The detection limits with the present HPLC/ICP-AES system were about 0.001-0.3 μg/mL with a 100-μL sample injection. The calibration curves obtained by the peak height measurements showed linear relationships in the concentration range below 500 μg/mL for all rare earth elements. A USGS rock standard sample, rare earth ores, and high-purity lanthanide reagents (>99.9%) were successfully analyzed without spectral interferences

  2. Evaluation of VITEK mass spectrometry (MS), a matrix-assisted laser desorption ionization time-of-flight MS system for identification of anaerobic bacteria.

    Science.gov (United States)

    Lee, Wonmok; Kim, Myungsook; Yong, Dongeun; Jeong, Seok Hoon; Lee, Kyungwon; Chong, Yunsop

    2015-01-01

    By conventional methods, the identification of anaerobic bacteria is more time consuming and requires more expertise than the identification of aerobic bacteria. Although the matrix-assisted laser desorption ionization time-of-flight mass spectrometry (MALDI-TOF MS) systems are relatively less studied, they have been reported to be a promising method for the identification of anaerobes. We evaluated the performance of the VITEK MS in vitro diagnostic (IVD; 1.1 database; bioMérieux, France) in the identification of anaerobes. We used 274 anaerobic bacteria isolated from various clinical specimens. The results for the identification of the bacteria by VITEK MS were compared to those obtained by phenotypic methods and 16S rRNA gene sequencing. Among the 249 isolates included in the IVD database, the VITEK MS correctly identified 209 (83.9%) isolates to the species level and an additional 18 (7.2%) at the genus level. In particular, the VITEK MS correctly identified clinically relevant and frequently isolated anaerobic bacteria to the species level. The remaining 22 isolates (8.8%) were either not identified or misidentified. The VITEK MS could not identify the 25 isolates absent from the IVD database to the species level. The VITEK MS showed reliable identifications for clinically relevant anaerobic bacteria.

  3. Proton-transfer reaction mass spectrometry (PTR-MS) for the authentication of regionally unique South African lamb

    NARCIS (Netherlands)

    Erasmus, Sara W.; Muller, Magdalena; Alewijn, Martin; Koot, Alex H.; Ruth, van Saskia M.; Hoffman, Louwrens C.

    2017-01-01

    The volatile fingerprints of South African lamb meat and fat were measured by proton-transfer mass spectrometry (PTR-MS) to evaluate it as an authentication tool. Meat and fat of the Longissimus lumborum (LL) of lambs from six different regions were assessed. Analysis showed that the volatile

  4. LC-IMS-MS Feature Finder: detecting multidimensional liquid chromatography, ion mobility and mass spectrometry features in complex datasets.

    Science.gov (United States)

    Crowell, Kevin L; Slysz, Gordon W; Baker, Erin S; LaMarche, Brian L; Monroe, Matthew E; Ibrahim, Yehia M; Payne, Samuel H; Anderson, Gordon A; Smith, Richard D

    2013-11-01

    The addition of ion mobility spectrometry to liquid chromatography-mass spectrometry experiments requires new, or updated, software tools to facilitate data processing. We introduce a command line software application LC-IMS-MS Feature Finder that searches for molecular ion signatures in multidimensional liquid chromatography-ion mobility spectrometry-mass spectrometry (LC-IMS-MS) data by clustering deisotoped peaks with similar monoisotopic mass, charge state, LC elution time and ion mobility drift time values. The software application includes an algorithm for detecting and quantifying co-eluting chemical species, including species that exist in multiple conformations that may have been separated in the IMS dimension. LC-IMS-MS Feature Finder is available as a command-line tool for download at http://omics.pnl.gov/software/LC-IMS-MS_Feature_Finder.php. The Microsoft.NET Framework 4.0 is required to run the software. All other dependencies are included with the software package. Usage of this software is limited to non-profit research to use (see README). rds@pnnl.gov. Supplementary data are available at Bioinformatics online.

  5. Two-dimensional HPLC coupled to ICP-MS and electrospray ionisation (ESI)-MS/MS for investigating the bioavailability in vitro of arsenic species from edible seaweed

    Energy Technology Data Exchange (ETDEWEB)

    Garcia-Sartal, Cristina; Barciela-Alonso, Maria del Carmen; Bermejo-Barrera, Pilar [University of Santiago de Compostela, Department of Analytical Chemistry, Nutrition and Bromatology, Faculty of Chemistry, Santiago de Compostela (Spain); Taebunpakul, Sutthinun [LGC Limited, Teddington, Middlesex (United Kingdom); Imperial College of Science, Technology and Medicine, South Kensington, Department of Materials, London (United Kingdom); National Institute of Metrology (Thailand), Pathumthani (Thailand); Stokes, Emma; Goenaga-Infante, Heidi [LGC Limited, Teddington, Middlesex (United Kingdom)

    2012-04-15

    Edible seaweed consumption is a route of exposure to arsenic. However, little attention has been paid to estimate the bioaccessibility and/or bioavailability of arsenosugars in edible seaweed and their possible degradation products during gastrointestinal digestion. This work presents first use of combined inductively coupled plasma mass spectroscopy (ICP-MS) with electrospray ionization tandem mass spectrometry (ESI-MS/MS) with two-dimensional HPLC (size exclusion followed by anion exchange) to compare the qualitative and quantitative arsenosugars speciation of different edible seaweed with that of their bioavailable fraction as obtained using an in vitro gastrointestinal digestion procedure. Optimal extraction conditions for As species from four seaweed namely kombu, wakame, nori and sea lettuce were selected as a compromise between As extraction efficiency and preservation of compound identity. For most investigated samples, the use of ammonium acetate buffer as extractant and 1 h sonication in a water bath followed by HPLC-ICP-MS resulted in 40-61% of the total As to be found in the buffered aqueous extract, of which 86-110% was present as arsenosugars (glycerol sugar, phosphate sugar and sulfonate sugar for wakame and kombu and glycerol sugar and phosphate sugar for nori). The exception was sea lettuce, for which the arsenosugar fraction (glycerol sugar, phosphate sugar) only comprised 44% of the total extracted As. Interestingly, the ratio of arsenobetaine and dimethylarsinic acid to arsenosugars in sea lettuce extracts seemed higher than that for the rest of investigated samples. After in vitro gastrointestinal digestion, approximately 11-16% of the total As in the solid sample was found in the dialyzates with arsenosugars comprising 93-120% and 41% of the dialyzable As fraction for kombu, wakame, nori and sea lettuce, respectively. Moreover, the relative As species distribution in seaweed-buffered extracts and dialyzates was found to be very similar

  6. Rapid Conformational Analysis of Protein Drugs in Formulation by Hydrogen/Deuterium Exchange Mass Spectrometry (HDX-MS)

    DEFF Research Database (Denmark)

    Esmail Nazari, Zeinab; van de Weert, Marco; Bou-Assaf, George

    2016-01-01

    Hydrogen Deuterium Exchange coupled to Mass Spectrometry (HDX-MS) has become an established method for analysis of protein higher-order structure. Here, we use HDX-MS methodology based on manual Solid-Phase Extraction (SPE) to allow fast and simplified conformational analysis of proteins under...... pharmaceutically relevant formulation conditions. Of significant practical utility, the methodology allows global HDX-MS analyses to be performed without refrigeration or external cooling of the setup. In Mode 1, we used DMSO-containing solvents for SPE, allowing the HDX-MS analysis to be performed at acceptable...... in formulation, using an internal HDX reference peptide (P7I) to control for any sample-to-sample variations in back exchange. Advantages of the methodology include low sample use, optimized excipient removal using multiple solvents, and fast data acquisition. Our results indicate that the SPE-HDX-MS system can...

  7. Determination of rivaroxaban in patient's plasma samples by anti-Xa chromogenic test associated to High Performance Liquid Chromatography tandem Mass Spectrometry (HPLC-MS/MS).

    Science.gov (United States)

    Derogis, Priscilla Bento Matos; Sanches, Livia Rentas; de Aranda, Valdir Fernandes; Colombini, Marjorie Paris; Mangueira, Cristóvão Luis Pitangueira; Katz, Marcelo; Faulhaber, Adriana Caschera Leme; Mendes, Claudio Ernesto Albers; Ferreira, Carlos Eduardo Dos Santos; França, Carolina Nunes; Guerra, João Carlos de Campos

    2017-01-01

    Rivaroxaban is an oral direct factor Xa inhibitor, therapeutically indicated in the treatment of thromboembolic diseases. As other new oral anticoagulants, routine monitoring of rivaroxaban is not necessary, but important in some clinical circumstances. In our study a high-performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS) method was validated to measure rivaroxaban plasmatic concentration. Our method used a simple sample preparation, protein precipitation, and a fast chromatographic run. It was developed a precise and accurate method, with a linear range from 2 to 500 ng/mL, and a lower limit of quantification of 4 pg on column. The new method was compared to a reference method (anti-factor Xa activity) and both presented a good correlation (r = 0.98, p plasma samples for rivaroxaban measurement by HPLC-MS/MS without interferences. The chromogenic and HPLC-MS/MS methods were highly correlated and should be used as clinical tools for drug monitoring. The method was applied successfully in a group of 49 real-life patients, which allowed an accurate determination of rivaroxaban in peak and trough levels.

  8. Ultrapressure liquid chromatography-tandem mass spectrometry assay using atmospheric pressure photoionization (UPLC-APPI-MS/MS) for quantification of 4-methoxydiphenylmethane in pharmacokinetic evaluation.

    Science.gov (United States)

    Farhan, Nashid; Fitzpatrick, Sean; Shim, Yun M; Paige, Mikell; Chow, Diana Shu-Lian

    2016-09-05

    4-Methoxydiphenylmethane (4-MDM), a selective augmenter of Leukotriene A4 Hydrolase (LTA4H), is a new anti-inflammatory compound for potential treatment of chronic obstructive pulmonary disease (COPD). Currently, there is no liquid chromatography tandem mass spectrometric (LC-MS/MS) method for the quantification of 4-MDM. A major barrier for developing the LC-MS/MS method is the inability of electrospray ionization (ESI) and atmospheric pressure chemical ionization (APCI) to ionize 4-MDM due to its hydrophobicity and lack of any functional group for ionization. With the advent of atmospheric pressure photoionization (APPI) technique, many hydrophobic compounds have been demonstrated to ionize by charge transfer reactions. In this study, a highly sensitive ultrapressure liquid chromatography tandem mass spectrometry assay using atmospheric pressure photoionization (UPLC-APPI-MS/MS) for the quantifications of 4-MDM in rat plasma has been developed and validated. 4-MDM was extracted from the plasma by solid phase extraction (SPE) and separated chromatographically using a reverse phase C8 column. The photoionization (PI) was achieved by introducing anisole as a dopant to promote the reaction of charge transfer. The assay with a linear range of 5 (LLOQ)-400ngmL(-1) met the regulatory requirements for accuracy, precision and stability. The validated assay was employed to quantify the plasma concentrations of 4-MDM after an oral dosing in Sprague Dawley (SD) rats. Copyright © 2016 Elsevier B.V. All rights reserved.

  9. Tandem mass spectrometry approach for the investigation of the steroidal metabolism: structure-fragmentation relationship (SFR) in anabolic steroids and their metabolites by ESI-MS/MS analysis.

    Science.gov (United States)

    Musharraf, Syed Ghulam; Ali, Arslan; Khan, Naik Tameem; Yousuf, Maria; Choudhary, Muhammad Iqbal; Atta-ur-Rahman

    2013-02-01

    Electrospray ionization tandem mass spectrometry (ESI-MS/MS) was used to investigate the effect of different substitutions introduced during metabolism on fragmentation patterns of four anabolic steroids including methyltestosterone, methandrostenolone, cis-androsterone and adrenosterone, along with their metabolites. Collision-induced dissociation (CID) analysis was performed to correlate the major product ions of 19 steroids with structural features. The analysis is done to portray metabolic alteration, such as incorporation or reduction of double bonds, hydroxylations, and/or oxidation of hydroxyl moieties to keto functional group on steroidal skeleton which leads to drastically changed product ion spectra from the respective classes of steroids, therefore, making them difficult to identify. The comparative ESI-MS/MS study also revealed some characteristic peaks to differentiate different steroidal metabolites and can be useful for the unambiguous identification of anabolic steroids in biological fluid. Moreover, LC-ESI-MS/MS analysis of fermented extract of methyltestosterone, obtained by Macrophomina phaseolina was also investigated. Copyright © 2012 Elsevier Inc. All rights reserved.

  10. A Proof of Concept to Bridge the Gap between Mass Spectrometry Imaging, Protein Identification and Relative Quantitation: MSI~LC-MS/MS-LF

    Directory of Open Access Journals (Sweden)

    Laëtitia Théron

    2016-10-01

    Full Text Available Mass spectrometry imaging (MSI is a powerful tool to visualize the spatial distribution of molecules on a tissue section. The main limitation of MALDI-MSI of proteins is the lack of direct identification. Therefore, this study focuses on a MSI~LC-MS/MS-LF workflow to link the results from MALDI-MSI with potential peak identification and label-free quantitation, using only one tissue section. At first, we studied the impact of matrix deposition and laser ablation on protein extraction from the tissue section. Then, we did a back-correlation of the m/z of the proteins detected by MALDI-MSI to those identified by label-free quantitation. This allowed us to compare the label-free quantitation of proteins obtained in LC-MS/MS with the peak intensities observed in MALDI-MSI. We managed to link identification to nine peaks observed by MALDI-MSI. The results showed that the MSI~LC-MS/MS-LF workflow (i allowed us to study a representative muscle proteome compared to a classical bottom-up workflow; and (ii was sparsely impacted by matrix deposition and laser ablation. This workflow, performed as a proof-of-concept, suggests that a single tissue section can be used to perform MALDI-MSI and protein extraction, identification, and relative quantitation.

  11. [Simultaneous determination of 7 arsenic species in chicken muscle and chicken liver with high performance liquid chromatography-inductively coupled plasma mass spectrometry].

    Science.gov (United States)

    Yang, Lijun; Hu, Qiaoru; Guo, Wei; Liu, Yumin; Song, Xiaohua; Zhang, Pengcheng

    2011-05-01

    A method for the simultaneous determination of 7 arsenic species was developed with high performance liquid chromatography and inductively coupled plasma mass spectrometry (HPLC-ICP-MS). The sample was extracted with artificial gastric juice. The HPLC separation was performed on an anion analytical column utilizing a gradient elution program of ammonium carbonate and water as the mobile phase. Identification and quantification were achieved by ICP-MS. Good linearities of 7 arsenic species were observed in the range from 1 microg/kg to 50 microg/kg with the correlation coefficients greater than 0.999. The average recoveries of 7 arsenic species spiked at the three levels of 1, 2 and 10 microg/kg ranged from 84.3% to 106.6% with the relative standard deviations of 1.4%-4.2%. The quantification limits of 7 arsenic species were 1 microg/kg. The method was proved to be good reproducibility, high sensitivity and simple preprocessing. This method is suitable for the simultaneous determination of 7 arsenic species in chicken muscle and chicken liver.

  12. Method development for speciation analysis of nanoparticle and ionic forms of gold in biological samples by high performance liquid chromatography hyphenated to inductively coupled plasma mass spectrometry

    Science.gov (United States)

    Malejko, Julita; Świerżewska, Natalia; Bajguz, Andrzej; Godlewska-Żyłkiewicz, Beata

    2018-04-01

    A new method based on coupling high performance liquid chromatography (HPLC) to inductively coupled plasma mass spectrometry (ICP MS) has been developed for the speciation analysis of gold nanoparticles (AuNPs) and dissolved gold species (Au(III)) in biological samples. The column type, the composition and the flow rate of the mobile phase were carefully investigated in order to optimize the separation conditions. The usefulness of two polymeric reversed phase columns (PLRP-S with 100 nm and 400 nm pore size) to separate gold species were investigated for the first time. Under the optimal conditions (PLRP-S400 column, 10 mmol L-1 SDS and 5% methanol as the mobile phase, 0.5 mL min-1 flow rate), detection limits of 2.2 ng L-1 for Au(III), 2.8 ng L-1 for 10 nm AuNPs and 3.7 ng L-1 for 40 nm AuNPs were achieved. The accuracy of the method was proved by analysis of reference material RM 8011 (NIST) of gold nanoparticles of nominal diameter of 10 nm. The HPLC-ICP MS method has been successfully applied to the detection and size characterization of gold species in lysates of green algae Acutodesmus obliquus, typical representative of phytoplankton flora, incubated with 10 nm AuNPs or Au(III).

  13. pyOpenMS: a Python-based interface to the OpenMS mass-spectrometry algorithm library.

    Science.gov (United States)

    Röst, Hannes L; Schmitt, Uwe; Aebersold, Ruedi; Malmström, Lars

    2014-01-01

    pyOpenMS is an open-source, Python-based interface to the C++ OpenMS library, providing facile access to a feature-rich, open-source algorithm library for MS-based proteomics analysis. It contains Python bindings that allow raw access to the data structures and algorithms implemented in OpenMS, specifically those for file access (mzXML, mzML, TraML, mzIdentML among others), basic signal processing (smoothing, filtering, de-isotoping, and peak-picking) and complex data analysis (including label-free, SILAC, iTRAQ, and SWATH analysis tools). pyOpenMS thus allows fast prototyping and efficient workflow development in a fully interactive manner (using the interactive Python interpreter) and is also ideally suited for researchers not proficient in C++. In addition, our code to wrap a complex C++ library is completely open-source, allowing other projects to create similar bindings with ease. The pyOpenMS framework is freely available at https://pypi.python.org/pypi/pyopenms while the autowrap tool to create Cython code automatically is available at https://pypi.python.org/pypi/autowrap (both released under the 3-clause BSD licence). © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  14. Improved sensitivity using liquid chromatography mass spectrometry (LC-MS) for detection of propyl chloroformate derivatised β-N-methylamino-L-alanine (BMAA) in cyanobacteria

    OpenAIRE

    Esterhuizen-Londt, M; Downing, S; Downing, TG

    2011-01-01

    β-N-methylamino-L-alanine (BMAA) is a difficult molecule to detect, primarily due to its presence in low concentrations in complex matrices. This has resulted in contradictory reports on the presence of BMAA in cyanobacteria. We report improved sensitivity of detection using propyl chloroformate derivatisation, liquid chromatographic (LC) separation, and single quadrupole mass spectrometry (MS) detection. Triple quadrupole mass spectrometry (MS/MS) was used to confirm the identity of BMAA in ...

  15. Analysis of banned veterinary drugs and herbicide residues in shellfish by liquid chromatography-tandem mass spectrometry (LC/MS/MS) and gas chromatography-tandem mass spectrometry (GC/MS/MS)

    International Nuclear Information System (INIS)

    Chang, Geng-Ruei; Chen, Hui-Shan; Lin, Feng-Yi

    2016-01-01

    Seafood safety is a crucial public health concern for consumers. In this study, we applied a validated method to analyze the residue of banned veterinary drugs in shellfish, namely chloramphenicol, malachite green, leucomalachite green, and nitrofuran metabolites; additionally, the QuEChERS method was employed to detect 76 herbicides by LC/MS/MS and GC/MS/MS. In total, 42 shellfish samples, which included hard clams, freshwater clams, and oysters, were collected from aquafarms and production areas in Taiwan during 2012. Our results revealed 3.8 ng/g of chloramphenicol in one hard clam, 19.9–32.1 ng/g of ametryn in two hard clams, 16.1–60.1 ng/g of pendimethalin in four hard clams, and 17.0 ng/g of mefenacet in one oyster, indicating that 19.1% of the samples contained residues from banned veterinary drugs and pesticides. These data can be used to monitor the residue of veterinary drugs and pesticides in aquatic organisms and as a reference for food safety. - Highlights: • A certified method was employed for analyzing residues of banned veterinary drugs and herbicides in shellfish samples. • The trace levels of chloramphenicol, ametryn, pendimethalin were detected in hard clam samples. • For ensuring food safety, continual monitoring of aquatic products is necessary.

  16. Phenolic profiling of Portuguese propolis by LC-MS spectrometry: uncommon propolis rich in flavonoid glycosides.

    Science.gov (United States)

    Falcão, Soraia I; Vale, Nuno; Gomes, Paula; Domingues, Maria R M; Freire, Cristina; Cardoso, Susana M; Vilas-Boas, Miguel

    2013-01-01

    Propolis is a chemically complex resinous substance collected by honeybees (Apis mellifera) from tree buds, comprising plant exudates, secreted substances from bee metabolism, pollen and waxes. Its chemical composition depends strongly on the plant sources available around the beehive, which have a direct impact in the quality and bioactivity of the propolis. Being as Portugal is a country of botanical diversity, the phenolic characterisation of propolis from the different regions is a priority. Extensive characterisation of the phenolic composition of Portuguese propolis from different continental regions and islands. Forty propolis ethanolic extracts were analysed extensively by liquid chromatography with diode-array detection coupled to electrospray ionisation tandem mass spectrometry (LC-DAD-ESI-MS(n) ). Seventy-six polyphenols were detected in the samples and two groups of propolis were established: the common temperate propolis, which contained the typical poplar phenolic compounds such as flavonoids and their methylated/esterified forms, phenylpropanoid acids and their esters, and an uncommon propolis type with an unusual composition in quercetin and kaempferol glycosides - some of them never described in propolis. The method allowed the establishment of the phenolic profile of Portuguese propolis from different geographical locations, and the possibility to use some phenolic compounds, such as kaempferol-dimethylether, as geographical markers. Data suggest that other botanical species in addition to poplar trees can be important sources of resins for Portuguese propolis. Copyright © 2012 John Wiley & Sons, Ltd.

  17. Liquid chromatography coupled with tandem mass spectrometry (LC-MS/MS) based bioavailability determination of the major classes of phytochemicals.

    Science.gov (United States)

    Stylos, Evgenios; Chatziathanasiadou, Maria V; Syriopoulou, Aggeliki; Tzakos, Andreas G

    2017-03-15

    Natural products derived from plants have served as an inexhausted source for drug discovery and drug development. They have been evolutionary amplified with drug-like properties and have already illustrated immense therapeutic potential over an array of different diseases. However, their incorporation in the drug discovery pipeline has been diminished the last two decades. This was probably due to barriers related to their inherent difficulties to be integrated in high-throughput screening assays as also their largely unexplored bioavailability. Analytical procedures have come into the spotlight, a result of the continuous development of the instrumentation's capabilities as far as detection and separation is concerned. Integral part of this technological evolution is LC-MS instrumentation and its extended use for the determination of various compounds. The fact that it provides extra sensitivity, specificity and good separation in complex samples, makes LC-MS/MS the ultimate tool in the determination of many types of chemical compounds, such as phytochemicals. Herein, we focus on the achievements of the last five years in quantitative analysis of the major classes of phytochemicals (flavonoids, alkaloids, terpenes, glycosides and saponins) in plasma, through LC-MS/MS, as also their bioavailability. Copyright © 2016 Elsevier B.V. All rights reserved.

  18. End-group characterisation of poly(propylene glycol)s by means of electrospray ionisation-tandem mass spectrometry (ESI-MS/MS).

    Science.gov (United States)

    Jackson, Anthony T; Slade, Susan E; Thalassinos, Konstantinos; Scrivens, James H

    2008-10-01

    The end-group functionalisation of a series of poly(propylene glycol)s has been characterised by means of electrospray ionisation-tandem mass spectrometry (ESI-MS/MS). A series of peaks with mass-to-charge ratios that are close to that of the precursor ion were used to generate information on the end-group functionalities of the poly(propylene glycol)s. Fragment ions resulting from losses of both of the end groups were noted from some of the samples. An example is presented of how software can be used to significantly reduce the length of time involved in data interpretation (which is typically the most time-consuming part of the analysis).

  19. Analysis of perchlorate in foods and beverages by ion chromatography coupled with tandem mass spectrometry (IC-ESI-MS/MS)

    Energy Technology Data Exchange (ETDEWEB)

    El Aribi, Houssain [Applied Biosystems/MDS Sciex, 71 Four Valley Drive, Concord, Ont., L4K 4V8 (Canada)]. E-mail: houssain.aribi@sciex.com; Le Blanc, Yves J.C. [Applied Biosystems/MDS Sciex, 71 Four Valley Drive, Concord, Ont., L4K 4V8 (Canada); Antonsen, Stephen [Dionex Canada Ltd., 1540 Cornwall Road, Oakville, Ont., L6J 7W5 (Canada); Sakuma, Takeo [Applied Biosystems/MDS Sciex, 71 Four Valley Drive, Concord, Ont., L4K 4V8 (Canada)

    2006-05-10

    A new IC-ESI-MS/MS method, with simple sample preparation procedure, has been developed for quantification and confirmation of perchlorate (ClO{sub 4} {sup -}) anions in water, fresh and canned food, wine and beer samples at low part-per-trillion (ng l{sup -1}) levels. To the best of our knowledge, this is the first time an analytical method is used for determination of perchlorate in wine and beer samples. The IC-ESI-MS/MS instrumentation consisted of an ICS-2500 ion chromatography (IC) system coupled to either an API 2000{sup TM} or an API 3200{sup TM} mass spectrometer. The IC-ESI-MS/MS system was optimized to monitor two pairs of precursor and fragment ion transitions, i.e., multiple reaction monitoring (MRM). All samples had oxygen-18 isotope labeled perchlorate internal standard (ISTD) added prior to extraction. Chlorine isotope ratio ({sup 35}Cl/{sup 37}Cl) was used as a confirmation tool. The transition of {sup 35}Cl{sup 16}O{sub 4} {sup -} (m/z 98.9) into {sup 35}Cl{sup 16}O{sub 3} {sup -} (m/z 82.9) was monitored for quantifying the main analyte; the transition of {sup 37}Cl{sup 16}O{sub 4} {sup -} (m/z 100.9) into {sup 37}Cl{sup 16}O{sub 3} {sup -} (m/z 84.9) was monitored for examining a proper isotopic abundance ratio of {sup 35}Cl/{sup 37}Cl; and the transition of {sup 35}Cl{sup 18}O{sub 4} {sup -} (m/z 107.0) into {sup 35}Cl{sup 18}O{sub 3} {sup -} (m/z 89.0) was monitored for quantifying the internal standard. The minimum detection limit (MDL) for this method in de-ionized water is 5 ng l{sup -1} (ppt) using the API 2000{sup TM} mass spectrometer and 0.5 ng l{sup -1} using the API 3200{sup TM} mass spectrometer. Over 350 food and beverage samples were analyzed mostly in triplicate. Except for four, all samples were found to contain measurable amounts of perchlorate. The levels found ranged from 5 ng l{sup -1} to 463.5 {+-} 6.36 {mu}g kg{sup -1} using MRM 98.9 {sup {yields}} 82.9 and 100 {mu}l injection.

  20. Quantification of isoflavones in coffee by using solid phase extraction (SPE) and high-performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS).

    Science.gov (United States)

    Caprioli, Giovanni; Navarini, Luciano; Cortese, Manuela; Ricciutelli, Massimo; Torregiani, Elisabetta; Vittori, Sauro; Sagratini, Gianni

    2016-09-01

    A new method for extracting isoflavones from espresso coffee (EC) was coupled with high-performance liquid chromatography-tandem mass spectrometry (MS/MS) for the first time to analyse five isoflavones, which included both a glycosilated form, genistin and the aglycons daidzein, genistein, formononetin and biochanin A. Isoflavones were extracted from coffee samples using methanol, stored in a freezer overnight to precipitate proteic or lipidic residues and purified on SPE C18 cartridges before high-performance liquid chromatography-MS/MS analysis. The recovery percentages obtained by spiking the matrix at concentrations of 10 and 100 µg l(-1) with a standard mixture of isoflavones were in the range of 70 to 104%. The limits of detection and limits of quantification were in the range of 0.015-0.3 µg l(-1) and 0.05-1 µg l(-1) , respectively. Once validated, the method was used to analyze the concentrations of isoflavones in six ECs and ten ground coffee samples. Only formononetin and biochanin A were found, and their respective concentrations ranged from 0.36 to 0.41 µg l(-1) and from 0.58 to 3.26 µg l(-1) in ECs and from 0.36 to 4.27 µg kg(-1) and from 0.71 to 3.95 µg kg(-1) in ground coffees. This method confirms the high specificity and selectivity of MS/MS systems for detecting bioactives in complex matrices such as coffee.Copyright © 2016 John Wiley & Sons, Ltd. Copyright © 2016 John Wiley & Sons, Ltd.

  1. Detection of a rare BCR-ABL tyrosine kinase fusion protein in H929 multiple myeloma cells using immunoprecipitation (IP)-tandem mass spectrometry (MS/MS).

    Science.gov (United States)

    Breitkopf, Susanne B; Yuan, Min; Pihan, German A; Asara, John M

    2012-10-02

    Hypothesis directed proteomics offers higher throughput over global analyses. We show that immunoprecipitation (IP)-tandem mass spectrometry (LC-MS/MS) in H929 multiple myeloma (MM) cancer cells led to the discovery of a rare and unexpected BCR-ABL fusion, informing a therapeutic intervention using imatinib (Gleevec). BCR-ABL is the driving mutation in chronic myeloid leukemia (CML) and is uncommon to other cancers. Three different IP-MS experiments central to cell signaling pathways were sufficient to discover a BCR-ABL fusion in H929 cells: phosphotyrosine (pY) peptide IP, p85 regulatory subunit of phosphoinositide-3-kinase (PI3K) IP, and the GRB2 adaptor IP. The pY peptides inform tyrosine kinase activity, p85 IP informs the activating adaptors and receptor tyrosine kinases (RTKs) involved in AKT activation and GRB2 IP identifies RTKs and adaptors leading to ERK activation. Integration of the bait-prey data from the three separate experiments identified the BCR-ABL protein complex, which was confirmed by biochemistry, cytogenetic methods, and DNA sequencing revealed the e14a2 fusion transcript. The tyrosine phosphatase SHP2 and the GAB2 adaptor protein, important for MAPK signaling, were common to all three IP-MS experiments. The comparative treatment of tyrosine kinase inhibitor (TKI) drugs revealed only imatinib, the standard of care in CML, was inhibitory to BCR-ABL leading to down-regulation of pERK and pS6K and inhibiting cell proliferation. These data suggest a model for directed proteomics from patient tumor samples for selecting the appropriate TKI drug(s) based on IP and LC-MS/MS. The data also suggest that MM patients, in addition to CML patients, may benefit from BCR-ABL diagnostic screening.

  2. Mass Spectrometry (LC-MS-MS) as a Tool in the Maillard Reaction Optimisation and Characterisation of New 6-methoxy-tetrahydro-β-carboline Derivatives

    International Nuclear Information System (INIS)

    Goh, T.B.; Mordi, M.N.; Mansor, S.M.

    2015-01-01

    Four new 6-methoxy-tetrahydro-β-carboline derivatives (1-6- methoxy-1-phenyl-2,3,4,9-tetrahydro-1H-pyrido[3,4-b]indole,2-6-methoxy-1- (4-methoxyphenyl)-2,3,4,9-tetrahydro-1H-pyrido[3,4-b]indole, 3-6-methoxy-1-methyl-2,3,4,9-tetrahydro-1H-pyrido[3,4-b]indole and 4-2-methoxy-4-(6-methoxy-2,3,4,9-tetrahydro-1H-pyrido[3,4-b]indol-1-yl) phenol) were prepared via the Maillard reaction using 5-methoxytryptamine and various aldehydes in water. The synthesis reaction conditions were optimised in catalyst loading, temperature and time using LC-MS for optimum yields. Surface response methodology and contour plot was selected as an approach for optimisation. The optimum yield could be achieved below 50 degree Celsius within 5 h at 7 mole % catalyst loading at yields > 70 %. The β-carboline compounds produced were characterised using electrospray ionization mass spectrometry (ESI-MS) and electrospray tandem mass (ESI-MS/MS). The mass fragmentation patterns of this group of heterocyclic tetrahydro-β-carboline compounds are described herein. (author)

  3. Analysing persistent organic pollutants in eggs, blood and tissue of the green sea turtle (Chelonia mydas) using gas chromatography with tandem mass spectrometry (GC-MS/MS)

    Energy Technology Data Exchange (ETDEWEB)

    Merwe, Jason Paul van de; Lee, Shing Yip [Griffith University, Griffith School of Environment and Australian Rivers Institute, Gold Coast, QLD (Australia); Hodge, Mary [Queensland Health Scientific Services, Queensland Government, Coopers Plains, QLD (Australia); Whittier, Joan Margaret [Univ. of Queensland, St. Lucia (Australia). School of Biomedical Sciences

    2009-03-15

    Investigation into persistent organic pollutants (POPs) in sea turtles is an important area of conservation research due to the harmful effects of these chemicals. However, the analysis of POPs in the green sea turtle (Chelonia mydas) has been limited by methods with relatively high limits of detection and high costs associated with multiple sample injections into complex arrangements of analytical equipment. The present study aimed to develop a method that could detect a large number of POPs in the blood, eggs and tissue of C. mydas at trace concentrations. A gas chromatography with tandem mass spectrometry (GC-MS/MS) method was developed that could report 125 POP compounds to a limit of detection of <35 pg g{sup -1} using a single sample injection. The recoveries of internal standards ranged from 30% to 96%, and the standard reference materials were reported to within 70% of the certified values. The coefficient of variation of ten replicates of pooled egg sample was <20% for all compounds, indicating low within-run variation. This GC-MS/MS method is an improvement of previous methods for analysing POPs in C. mydas in that more compounds can be reported at lower concentrations and the accuracy and precision of the method are sound. This is particularly important for C. mydas as they occupy a low trophic level and have lower concentrations of POPs. This method is also simple to set up, and there are minimal differences in sample preparation for the different tissue types. (orig.)

  4. Rapid extraction combined with LC-tandem mass spectrometry (CREM-LC/MS/MS) for the determination of ciguatoxins in ciguateric fish flesh.

    Science.gov (United States)

    Lewis, Richard J; Yang, Aijun; Jones, Alun

    2009-07-01

    Ciguatera is a significant food borne disease caused by potent polyether toxins known as ciguatoxins, which accumulate in the flesh of ciguateric fish at risk levels above 0.1 ppb. The management of ciguatera has been hindered by the lack of analytical methods to detect and quantify clinically relevant levels of ciguatoxin in easily prepared crude extracts of fish. Here we report a ciguatoxin rapid extraction method (CREM) that allows the rapid preparation of fish flesh extracts for the detection and quantification of ciguatoxin by gradient reversed-phase liquid chromatography-tandem mass spectrometry (LC/MS/MS). CREM-LC/MS/MS delivers a linear response to P-CTX-1 spiked into fish prior to extraction. A similar response was obtained for P-CTX-1 spiked after extraction, indicating >95% extraction efficiency was achieved overall and 85% at the limit of quantification (0.1 ppb). Using this approach, levels >or=0.1 ppb P-CTX-1 could be detected and quantified from an extract of 2g fish flesh, making it suitable as a confirmatory assay for suspect ciguateric carnivorous fish in the Pacific Ocean. The approach is designed to simplify the extraction and analysis of multiple samples per day.

  5. A proteomics method using immunoaffinity fluorogenic derivatization-liquid chromatography/tandem mass spectrometry (FD-LC-MS/MS) to identify a set of interacting proteins.

    Science.gov (United States)

    Nakata, Katsunori; Saitoh, Ryoichi; Ishigai, Masaki; Imai, Kazuhiro

    2018-02-01

    Biological functions in organisms are usually controlled by a set of interacting proteins, and identifying the proteins that interact is useful for understanding the mechanism of the functions. Immunoprecipitation is a method that utilizes the affinity of an antibody to isolate and identify the proteins that have interacted in a biological sample. In this study, the FD-LC-MS/MS method, which involves fluorogenic derivatization followed by separation and quantification by HPLC and finally identification of proteins by HPLC-tandem mass spectrometry, was used to identify proteins in immunoprecipitated samples, using heat shock protein 90 (HSP90) as a model of an interacting protein in HepaRG cells. As a result, HSC70 protein, which was known to form a complex with HSP90, was isolated, together with three different types of HSP90-beta. The results demonstrated that the proposed immunoaffinity-FD-LC-MS/MS method could be useful for simultaneously detecting and identifying the proteins that interact with a certain protein. Copyright © 2017 John Wiley & Sons, Ltd.

  6. Determination of Tributyltin in Seafood Based on Magnetic Molecularly Imprinted Polymers Coupled with High-Performance Liquid Chromatography-Inductively Coupled Plasma Mass Spectrometry

    Directory of Open Access Journals (Sweden)

    Hua Yang

    2017-01-01

    Full Text Available In this study, Fe3O4 was adopted as a carrier for surface molecular imprinting with two-stage polymerization. First, the functional monomer (methacrylic acid, MAA was modified on the surface of Fe3O4, which was then polymerized with the template molecule (tributyltin, TBT, cross linking agent (ethylene glycol dimethacrylate, EGDMA, and porogen (acetonitrile, hereby successfully preparing Fe3O4@MIPs prone to specifically identify TBT. The physical properties of Fe3O4@MIPs were then characterized, and adsorption and selection capacities were also assessed. Compared with conventional imprinting polymers, this magnetic molecular imprinting polymer (MIP displayed significantly increased and more specific adsorption. Meanwhile, its pretreatment was simpler and faster due to magnetic separation characteristics. Using magnetic MIPs as adsorbents for enrichment and separation, detection limit, recovery rate, and linear range were 1.0 ng g−1, 79.74–95.72%, and 5 ng g−1~1000 ng g−1, respectively, for a number of seafood samples. High-performance liquid chromatography-inductively coupled plasma mass spectrometry (HPLC-ICP-MS was used to analyze Tegillarca granosa, mussels, large yellow croaker, and other specimens, with recovery rates of 79.74–95.72% and RSD of 1.3%–4.7%. Overall, this method has a shorter total analysis time, lower detection limit, and wider linear range and can be more effectively applied to determine MAA in seawater and seafood.

  7. Fingerprinting Deepwater Horizon Oil in the northern Gulf of Mexico using biomarkers and Gas Chromatography-Triple Quadrupole Mass Spectrometry (GC/MS/MS)

    Science.gov (United States)

    Adhikari, P. L.; Overton, E. B.; Maiti, K.; Wong, R. L.

    2016-02-01

    Petroleum biomarkers such as hopanes, steranes, and triaromatic steroids are more persistent than alkanes and aromatic compounds. Thus, they are often used to track spilled oil in the environments and as a proxy for weathering processes. The present study utilizes water samples, suspended and sinking particles, and seafloor sediments collected during 2011-2013 from various locations of the northern Gulf of Mexico with wide range of contaminated oil for Deepwater Horizon (DWH) oil fingerprinting. The MC252 source oil along with the samples collected in this study were analyzed using a gas chromatography coupled with a triple quadrupole mass spectrometry (GC/MS/MS) in Multiple Reaction Monitoring (MRM) mode and the results were compared with results from commonly used GC/MS selective ion monitoring (SIM) method. The results indicate that the MRM method separates interfering ions from interfering compounds and can be a powerful analytical strategy for a reliable identification and determination of trace levels of biomarkers in complex matrices. Source indicators such as the MRM fragment ion chromatograms of the biomarkers and their diagnostic ratios in samples were compared with the MC252 source oil. The preliminary results show that the biomarkers were below detection limits in dissolved samples. However, in few particulate and seafloor sediment samples, primarily from the immediate vicinity of the Macondo wellhead, contained their patterns. The results also illustrate that these biomarker compounds have been weathered within 1-3 years following the oil spill, and their DWH oil signature in some of these samples reflects this weathering.

  8. Ultra-performance liquid chromatography tandem mass-spectrometry (uplc-ms/ms) for the rapid, simultaneous analysis of thiamin, riboflavin, flavin adenine dinucleotide, nicotinamide and pyridoxal in human milk

    Science.gov (United States)

    A novel, rapid and sensitive Ultra Performance Liquid-Chromatography tandem Mass-Spectrometry (UPLC-MS/MS) method for the simultaneous determination of several B-vitamins in human milk was developed. Resolution by retention time or multiple reaction monitoring (MRM) for thiamin, riboflavin, flavin a...

  9. Differential Mobility Spectrometry-Mass Spectrometry (DMS-MS) in Radiation Biodosimetry: Rapid and High-Throughput Quantitation of Multiple Radiation Biomarkers in Nonhuman Primate Urine

    Science.gov (United States)

    Chen, Zhidan; Coy, Stephen L.; Pannkuk, Evan L.; Laiakis, Evagelia C.; Fornace, Albert J.; Vouros, Paul

    2018-05-01

    High-throughput methods to assess radiation exposure are a priority due to concerns that include nuclear power accidents, the spread of nuclear weapon capability, and the risk of terrorist attacks. Metabolomics, the assessment of small molecules in an easily accessible sample, is the most recent method to be applied for the identification of biomarkers of the biological radiation response with a useful dose-response profile. Profiling for biomarker identification is frequently done using an LC-MS platform which has limited throughput due to the time-consuming nature of chromatography. We present here a chromatography-free simplified method for quantitative analysis of seven metabolites in urine with radiation dose-response using urine samples provided from the Pannkuk et al. (2015) study of long-term (7-day) radiation response in nonhuman primates (NHP). The stable isotope dilution (SID) analytical method consists of sample preparation by strong cation exchange-solid phase extraction (SCX-SPE) to remove interferences and concentrate the metabolites of interest, followed by differential mobility spectrometry (DMS) ion filtration to select the ion of interest and reduce chemical background, followed by mass spectrometry (overall SID-SPE-DMS-MS). Since no chromatography is used, calibration curves were prepared rapidly, in under 2 h (including SPE) for six simultaneously analyzed radiation biomarkers. The seventh, creatinine, was measured separately after 2500× dilution. Creatinine plays a dual role, measuring kidney glomerular filtration rate (GFR), and indicating kidney damage at high doses. The current quantitative method using SID-SPE-DMS-MS provides throughput which is 7.5 to 30 times higher than that of LC-MS and provides a path to pre-clinical radiation dose estimation. [Figure not available: see fulltext.

  10. Differential Mobility Spectrometry-Mass Spectrometry (DMS-MS) in Radiation Biodosimetry: Rapid and High-Throughput Quantitation of Multiple Radiation Biomarkers in Nonhuman Primate Urine.

    Science.gov (United States)

    Chen, Zhidan; Coy, Stephen L; Pannkuk, Evan L; Laiakis, Evagelia C; Fornace, Albert J; Vouros, Paul

    2018-05-07

    High-throughput methods to assess radiation exposure are a priority due to concerns that include nuclear power accidents, the spread of nuclear weapon capability, and the risk of terrorist attacks. Metabolomics, the assessment of small molecules in an easily accessible sample, is the most recent method to be applied for the identification of biomarkers of the biological radiation response with a useful dose-response profile. Profiling for biomarker identification is frequently done using an LC-MS platform which has limited throughput due to the time-consuming nature of chromatography. We present here a chromatography-free simplified method for quantitative analysis of seven metabolites in urine with radiation dose-response using urine samples provided from the Pannkuk et al. (2015) study of long-term (7-day) radiation response in nonhuman primates (NHP). The stable isotope dilution (SID) analytical method consists of sample preparation by strong cation exchange-solid phase extraction (SCX-SPE) to remove interferences and concentrate the metabolites of interest, followed by differential mobility spectrometry (DMS) ion filtration to select the ion of interest and reduce chemical background, followed by mass spectrometry (overall SID-SPE-DMS-MS). Since no chromatography is used, calibration curves were prepared rapidly, in under 2 h (including SPE) for six simultaneously analyzed radiation biomarkers. The seventh, creatinine, was measured separately after 2500× dilution. Creatinine plays a dual role, measuring kidney glomerular filtration rate (GFR), and indicating kidney damage at high doses. The current quantitative method using SID-SPE-DMS-MS provides throughput which is 7.5 to 30 times higher than that of LC-MS and provides a path to pre-clinical radiation dose estimation. Graphical Abstract.

  11. Optimisation and application of ICP-MS and alpha-spectrometry for determination of isotopic ratios of depleted uranium and plutonium in samples collected in Kosovo

    OpenAIRE

    Boulyga, S. F.; Testa, C.; Desideri, D.; Becker, J. S.

    2001-01-01

    The determination of environmental contamination with natural and artificial actinide isotopes and evaluation of their source requires precise isotopic determination of actinides, above all uranium and plutonium. This can be achieved by alpha spectrometry or by inductively coupled plasma mass spectrometry (ICP-MS) after chemical separation of actinides. The performance of a sector-field ICP-MS (ICP-SFMS) coupled to a low-flow micronebulizer with a membrane desolvation unit, "Aridus'', was stu...

  12. An appraisal on the degradation of paracetamol by TiO2/UV system in aqueous medium: product identification by gas chromatography-mass spectrometry (GC-MS)

    OpenAIRE

    Dalmázio,Ilza; Alves,Tânia M. A.; Augusti,Rodinei

    2008-01-01

    The advanced oxidation of paracetamol (1) promoted by TiO2/UV system in aqueous medium was investigated. Continuous monitoring by several techniques, such as UV-Vis spectroscopy, HPLC (high performance liquid chromatography), TOC (total organic carbon), and ESI-MS (electrospray ionization mass spectrometry), revealed that whereas the removal of paracetamol was highly efficient under these conditions, its mineralization was not likewise accomplished. GC-MS (gas chromatography-mass spectrometry...

  13. Quantitation of mycotoxins using direct analysis in real time (DART)-mass spectrometry (MS)

    Science.gov (United States)

    Ambient ionization represents a new generation of mass spectrometry ion sources which is used for rapid ionization of small molecules under ambient conditions. The combination of ambient ionization and mass spectrometry allows analyzing multiple food samples with simple or no sample treatment, or in...

  14. Critical assessment of ionization patterns and applications of ambient desorption/ionization mass spectrometry using FAPA-MS.

    Science.gov (United States)

    Brüggemann, Martin; Karu, Einar; Hoffmann, Thorsten

    2016-02-01

    Ambient desorption/ionization mass spectrometry (MS) has gained growing interest during the last decade due to its high analytical performance and yet simplicity. Here, one of the recently developed ambient desorption/ionization MS sources, the flowing atmospheric-pressure afterglow (FAPA) source, was investigated in detail regarding background ions and typical ionization patterns in the positive as well as the negative ion mode for a variety of compound classes, comprising alkanes, alcohols, aldehydes, ketones, carboxylic acids, organic peroxides and alkaloids. A broad range of signals for adducts and losses was found, besides the usually emphasized detection of quasimolecular ions, i.e. [M + H](+) and [M - H](-) in the positive and the negative mode, respectively. It was found that FAPA-MS is best suited for polar analytes containing nitrogen and/or oxygen functionalities, e.g. carboxylic acids, with low molecular weights and relatively high vapor pressures. In addition, the source was used in proof-of-principle studies, illustrating the capabilities and limitations of the technique: Firstly, traces of cocaine were detected and unambiguously identified on euro banknotes using FAPA ionization in combination with tandem MS, suggesting a correlation between cocaine abundance and age of the banknote. Secondly, FAPA-MS was used for the identification of acidic marker compounds in organic aerosol samples, indicating yet-undiscovered matrix and sample surface effects of ionization pathways in the afterglow region. Copyright © 2016 John Wiley & Sons, Ltd.

  15. Analyses of organochlorine pesticides residues in eels (Anguilla anguilla from Lake Garda using Gas chromatography coupled with Tandem Mass Spectrometry (GC-MS/MS.

    Directory of Open Access Journals (Sweden)

    Giuseppe Federico Labella

    2017-05-01

    Full Text Available Lake Garda is located in Insubria region, that is known for being the most populated and industrialized area of Italy (Camusso et al., 2001. Therefore, the Lake water, and also the fish species present, could be affected by environmental contamination.  European eel (Anguilla anguilla are considered as suitable matrix for biomonitoring environmental contaminants in European water (Belpaire et al., 2007, being widespread in many European waters and highly contaminated by lipophilic compounds, due to the high lipid content (up to 40% (Larsson et al., 1991. Moreover, eel is an edible species (its farming currently supplies approximately 45,000 tons/year (Nielsen et al., 2008, so it also represents a public health issue. Based on these considerations, the aim of this study was to evaluate the occurrence of fourteen organochlorine pesticides (OCs in forty-five eels (Anguilla anguilla from Lake Garda, using Accelerated Solvent Extraction (ASE procedure for the analytes extraction and Gas chromatography coupled with Tandem Mass Spectrometry (GC-MS/MS for the analysis of OCs. GC-MS/MS analysis was developed and validated according to the SANTE/11945/2015 guidelines.  Uncontaminated eel sample (previously checked for the presence of OCs and considered blank with a concentration of compounds < Limit of Detection were used for all procedure's optimization steps. For all the OCs analysed, satisfactory results were achieved. Regarding eel samples, several pesticides were detected, but DDTs (DDT and its metabolites were found with the highest prevalence (92 %. The concentration rage was from not detected (n.d. to 19000 ng g-1. Although DDTs levels in the environment are declining (Albaiges et al., 2011, they continue to bioaccumulate in tissues of human and animal and biomagnify in food chains.

  16. Multicenter validation of the VITEK MS v2.0 MALDI-TOF mass spectrometry system for the identification of fastidious gram-negative bacteria.

    Science.gov (United States)

    Branda, John A; Rychert, Jenna; Burnham, Carey-Ann D; Bythrow, Maureen; Garner, Omai B; Ginocchio, Christine C; Jennemann, Rebecca; Lewinski, Michael A; Manji, Ryhana; Mochon, A Brian; Procop, Gary W; Richter, Sandra S; Sercia, Linda F; Westblade, Lars F; Ferraro, Mary Jane

    2014-02-01

    The VITEK MS v2.0 MALDI-TOF mass spectrometry system's performance in identifying fastidious gram-negative bacteria was evaluated in a multicenter study. Compared with the reference method (DNA sequencing), the VITEK MS system provided an accurate, species-level identification for 96% of 226 isolates; an additional 1% were accurately identified to the genus level. © 2013.

  17. Simultaneous determination of vitamins A and D3 in dairy products by liquid chromatography-tandem mass spectrometry (LC-MS/MS)

    Science.gov (United States)

    Barakat, I. S. A.; Hammouri, M. K.; Habib, I.

    2015-10-01

    A potential method for simultaneous determination of vitamin A and vitamin D3 (25- hydroxyvitamin D3) in fresh milk samples is addressed. The method is based on combination of high performance liquid chromatography and mass spectrometry during the course of analysis. The method applied for determination of vitamins A and D3 on eighteen (18) different fresh milk samples using liquid chromatography along with tandem -mass spectrometry. The work describes the suitability of the proposed method for the simultaneous determination of both vitamins using LC-MS/MS as a specific and quantitative technique. The vitamins of milk were separated by C18 Thermo gold column(100mm × 4.6mm × 5 μm) with a flow rate of 1ml/min (using an isocratic mobile phase). The method was validated using duplicate analyses, relative recovery experiment, and comparative analysis with control samples. Liquid- liquid extraction was employed as a pre-concentration step with n-hexane - dichloromethane mixture (90%:10%) as an extraction solvent. The molecular ions (m/z) appeared near 286 and 385nm and for the base peaks were appeared near 255 and 355nm for vitamins A and D3. Good correlation coefficients were obtained, 0.9999 for vitamin D3 and 0.9994 for vitamin A. The limit of detection and the limit of quantification were found to be 0.09ng/ml and 0.54ng/ml for vitamin D3 and 0.32ng/ml and 1.8ng/ml and for vitamin A. The proposed method showed excellent recoveries, about 98% for both vitamins A and D3.

  18. Ambient infrared laser ablation mass spectrometry (AIRLAB-MS) with plume capture by continuous flow solvent probe

    Science.gov (United States)

    O'Brien, Jeremy T.; Williams, Evan R.; Holman, Hoi-Ying N.

    2017-10-31

    A new experimental setup for spatially resolved ambient infrared laser ablation mass spectrometry (AIRLAB-MS) that uses an infrared microscope with an infinity-corrected reflective objective and a continuous flow solvent probe coupled to a Fourier transform ion cyclotron resonance mass spectrometer is described. The efficiency of material transfer from the sample to the electrospray ionization emitter was determined using glycerol/methanol droplets containing 1 mM nicotine and is .about.50%. This transfer efficiency is significantly higher than values reported for similar techniques.

  19. Sensitivity of DF-ICP-MS, PERALS and alpha-spectrometry for the determination of actinides. A comparison

    International Nuclear Information System (INIS)

    Ayranov, M.; Kraehenbuehl, U.

    2009-01-01

    We applied three techniques (DF-ICP-MS, PERALS and alpha-spectrometry) for the determination of minor actinides at environmental levels. For each method the limit of detection and the resolution were estimated in order to study the content and isotopic composition of the actinides. Two international reference materials, IAEA-135 (Irish Sea Sediment) and IAEA-300 (Baltic Sea sediment) were analyzed for activity concentrations of 238 Pu, 239 Pu, 240 Pu, 241 Pu and 241 Am. The sensitivities of the three determination techniques were compared. (author)

  20. Inductively coupled plasma – Tandem mass spectrometry (ICP-MS/MS): A powerful and universal tool for the interference-free determination of (ultra)trace elements – A tutorial review

    Energy Technology Data Exchange (ETDEWEB)

    Balcaen, Lieve; Bolea-Fernandez, Eduardo [Ghent University, Department of Analytical Chemistry, Krijgslaan 281-S12, B-9000 Ghent (Belgium); Resano, Martín [University of Zaragoza, Department of Analytical Chemistry, Pedro Cerbuna 12, E-50009 Zaragoza (Spain); Vanhaecke, Frank, E-mail: Frank.Vanhaecke@UGent.be [Ghent University, Department of Analytical Chemistry, Krijgslaan 281-S12, B-9000 Ghent (Belgium)

    2015-09-24

    This paper is intended as a tutorial review on the use of inductively coupled plasma – tandem mass spectrometry (ICP-MS/MS) for the interference-free quantitative determination and isotope ratio analysis of metals and metalloids in different sample types. Attention is devoted both to the instrumentation and to some specific tools and procedures available for advanced method development. Next to the more typical reaction gases, e.g., H{sub 2}, O{sub 2} and NH{sub 3}, also the use of promising alternative gases, such as CH{sub 3}F, is covered, and the possible reaction pathways with those reactive gases are discussed. A variety of published applications relying on the use of ICP-MS/MS are described, to illustrate the added value of tandem mass spectrometry in (ultra)trace analysis. - Highlights: • First review on tandem ICP-mass spectrometry (ICP-MS/MS). • Clear description of operating principles of ICP-MS/MS. • Description on how to make use of product ion scans, precursor ion scans and neutral gain scans in method development. • Overview of applications published so far.

  1. Inductively coupled plasma – Tandem mass spectrometry (ICP-MS/MS): A powerful and universal tool for the interference-free determination of (ultra)trace elements – A tutorial review

    International Nuclear Information System (INIS)

    Balcaen, Lieve; Bolea-Fernandez, Eduardo; Resano, Martín; Vanhaecke, Frank

    2015-01-01

    This paper is intended as a tutorial review on the use of inductively coupled plasma – tandem mass spectrometry (ICP-MS/MS) for the interference-free quantitative determination and isotope ratio analysis of metals and metalloids in different sample types. Attention is devoted both to the instrumentation and to some specific tools and procedures available for advanced method development. Next to the more typical reaction gases, e.g., H_2, O_2 and NH_3, also the use of promising alternative gases, such as CH_3F, is covered, and the possible reaction pathways with those reactive gases are discussed. A variety of published applications relying on the use of ICP-MS/MS are described, to illustrate the added value of tandem mass spectrometry in (ultra)trace analysis. - Highlights: • First review on tandem ICP-mass spectrometry (ICP-MS/MS). • Clear description of operating principles of ICP-MS/MS. • Description on how to make use of product ion scans, precursor ion scans and neutral gain scans in method development. • Overview of applications published so far.

  2. Gas chromatography coupled to atmospheric pressure ionization mass spectrometry (GC-API-MS): Review

    International Nuclear Information System (INIS)

    Li, Du-Xin; Gan, Lin; Bronja, Amela; Schmitz, Oliver J.

    2015-01-01

    Although the coupling of GC/MS with atmospheric pressure ionization (API) has been reported in 1970s, the interest in coupling GC with atmospheric pressure ion source was expanded in the last decade. The demand of a “soft” ion source for preserving highly diagnostic molecular ion is desirable, as compared to the “hard” ionization technique such as electron ionization (EI) in traditional GC/MS, which fragments the molecule in an extensive way. These API sources include atmospheric pressure chemical ionization (APCI), atmospheric pressure photoionization (APPI), atmospheric pressure laser ionization (APLI), electrospray ionization (ESI) and low temperature plasma (LTP). This review discusses the advantages and drawbacks of this analytical platform. After an introduction in atmospheric pressure ionization the review gives an overview about the history and explains the mechanisms of various atmospheric pressure ionization techniques used in combination with GC such as APCI, APPI, APLI, ESI and LTP. Also new developments made in ion source geometry, ion source miniaturization and multipurpose ion source constructions are discussed and a comparison between GC-FID, GC-EI-MS and GC-API-MS shows the advantages and drawbacks of these techniques. The review ends with an overview of applications realized with GC-API-MS. - Highlights: • Atmospheric pressure ion sources (APCI, ESI, APPI, APLC etc) enable the coupling of LC-based high-end MS to GC. • APIs show advantages in selectivity and sensitivity compared with EI in GC-MS. • Accurate mass database in GC-APCI/MS is emerging as an alternative to GC-EI/MS database.

  3. Gas chromatography coupled to atmospheric pressure ionization mass spectrometry (GC-API-MS): Review

    Energy Technology Data Exchange (ETDEWEB)

    Li, Du-Xin; Gan, Lin; Bronja, Amela [University of Duisburg-Essen, Applied Analytical Chemistry, Universitaetsstr. 5-7, 45141 Essen (Germany); Schmitz, Oliver J., E-mail: oliver.schmitz@uni-due.de [University of Duisburg-Essen, Applied Analytical Chemistry, Universitaetsstr. 5-7, 45141 Essen (Germany)

    2015-09-03

    Although the coupling of GC/MS with atmospheric pressure ionization (API) has been reported in 1970s, the interest in coupling GC with atmospheric pressure ion source was expanded in the last decade. The demand of a “soft” ion source for preserving highly diagnostic molecular ion is desirable, as compared to the “hard” ionization technique such as electron ionization (EI) in traditional GC/MS, which fragments the molecule in an extensive way. These API sources include atmospheric pressure chemical ionization (APCI), atmospheric pressure photoionization (APPI), atmospheric pressure laser ionization (APLI), electrospray ionization (ESI) and low temperature plasma (LTP). This review discusses the advantages and drawbacks of this analytical platform. After an introduction in atmospheric pressure ionization the review gives an overview about the history and explains the mechanisms of various atmospheric pressure ionization techniques used in combination with GC such as APCI, APPI, APLI, ESI and LTP. Also new developments made in ion source geometry, ion source miniaturization and multipurpose ion source constructions are discussed and a comparison between GC-FID, GC-EI-MS and GC-API-MS shows the advantages and drawbacks of these techniques. The review ends with an overview of applications realized with GC-API-MS. - Highlights: • Atmospheric pressure ion sources (APCI, ESI, APPI, APLC etc) enable the coupling of LC-based high-end MS to GC. • APIs show advantages in selectivity and sensitivity compared with EI in GC-MS. • Accurate mass database in GC-APCI/MS is emerging as an alternative to GC-EI/MS database.

  4. Determination of rivaroxaban in patient’s plasma samples by anti-Xa chromogenic test associated to High Performance Liquid Chromatography tandem Mass Spectrometry (HPLC-MS/MS)

    Science.gov (United States)

    Derogis, Priscilla Bento Matos; Sanches, Livia Rentas; de Aranda, Valdir Fernandes; Colombini, Marjorie Paris; Mangueira, Cristóvão Luis Pitangueira; Katz, Marcelo; Faulhaber, Adriana Caschera Leme; Mendes, Claudio Ernesto Albers; Ferreira, Carlos Eduardo dos Santos; França, Carolina Nunes; Guerra, João Carlos de Campos

    2017-01-01

    Rivaroxaban is an oral direct factor Xa inhibitor, therapeutically indicated in the treatment of thromboembolic diseases. As other new oral anticoagulants, routine monitoring of rivaroxaban is not necessary, but important in some clinical circumstances. In our study a high-performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS) method was validated to measure rivaroxaban plasmatic concentration. Our method used a simple sample preparation, protein precipitation, and a fast chromatographic run. It was developed a precise and accurate method, with a linear range from 2 to 500 ng/mL, and a lower limit of quantification of 4 pg on column. The new method was compared to a reference method (anti-factor Xa activity) and both presented a good correlation (r = 0.98, p highly correlated and should be used as clinical tools for drug monitoring. The method was applied successfully in a group of 49 real-life patients, which allowed an accurate determination of rivaroxaban in peak and trough levels. PMID:28170419

  5. Development of a Multi-class Steroid Hormone Screening Method using Liquid Chromatography/Tandem Mass Spectrometry (LC-MS/MS)

    Science.gov (United States)

    Boggs, Ashley S. P.; Bowden, John A.; Galligan, Thomas M.; Guillette, Louis J.; Kucklick, John R.

    2016-01-01

    Monitoring complex endocrine pathways is often limited by indirect measurement or measurement of a single hormone class per analysis. There is a burgeoning need to develop specific direct-detection methods capable of providing simultaneous measurement of biologically relevant concentrations of multiple classes of hormones (estrogens, androgens, progestogens, and corticosteroids). The objectives of this study were to develop a liquid chromatography-tandem mass spectrometry (LC-MS/MS) method for multi-class steroid hormone detection using biologically relevant concentrations, then test limits of detection (LOD) in a high-background matrix by spiking charcoal-stripped fetal bovine serum (FBS) extract. Accuracy was tested with National Institute of Standards and Technology Standard Reference Materials (SRMs) with certified concentrations of cortisol, testosterone, and progesterone. 11-Deoxycorticosterone, 11-deoxycortisol, 17-hydroxypregnenolone, 17-hydroxyprogesterone, adrenosterone, androstenedione, cortisol, corticosterone, dehydroepiandrosterone, dihydrotestosterone, estradiol, estriol, estrone, equilin, pregnenolone, progesterone, and testosterone were also measured using isotopic dilution. Dansyl chloride (DC) derivatization was investigated maintaining the same method to improve and expedite estrogen analysis. Biologically relevant LODs were determined for 15 hormones. DC derivatization improved estrogen response two- to eight-fold, and improved chromatographic separation. All measurements had an accuracy ≤ 14 % difference from certified values (not accounting for uncertainty) and relative standard deviation ≤ 14 %. This method chromatographically separated and quantified biologically relevant concentrations of four hormone classes using highly specific fragmentation patterns and measured certified values of hormones that were previously split into three separate chromatographic methods. PMID:27039201

  6. Analytical and clinical performance of the new Fujirebio 25-OH vitamin D assay, a comparison with liquid chromatography-tandem mass spectrometry (LC-MS/MS) and three other automated assays

    OpenAIRE

    Saleh, Lanja; Mueller, Daniel; von Eckardstein, Arnold

    2015-01-01

    BACKGROUND: We evaluated the analytical and clinical performance of the new Lumipulse® G 25-OH vitamin D assay from Fujirebio, and compared it to a liquid chromatography-tandem mass spectrometry (LC-MS/MS) method and three other commercial automated assays. METHODS: Total 25 hydroxy vitamin D (25(OH)D) levels were measured in 100 selected serum samples from our routine analysis with Fujirebio 25(OH)D assay. The results were compared with those obtained with LC-MS/MS and three other automat...

  7. Applications of ICP-MS in marine analytical chemistry

    Energy Technology Data Exchange (ETDEWEB)

    McLaren, J W; Siu, K W.M.; Lam, J W; Willie, S N; Maxwell, P S; Palepu, A; Koether, M; Berman, S S [National Research Council of Canada, Ottawa, ON (Canada). Analytical Chemistry Section

    1990-07-01

    The versatility of ICP-MS in marine analytical chemistry is illustrated with applications to the multielement trace analysis of two recently released marine reference materials, the coastal seawater CASS-2 and the non-defatted lobster hepatopancreas tissue LUTS-1, and to the determination of tributyltin and dibutyltin in the harbour sediment reference material PACS-1 by HPLC-ICP-MS. Seawater analyses were performed after separation of the trace elements either by adsorption on immobilized 8-hydroxyquinoline or by reductive coprecipitation with iron and palladium. Simultaneous determination of seven trace elements in LUTS-1, including mercury, by isotope dilution ICP-MS, was achieved after dissolution by microwave digestion with nitric acid and hydrogen peroxide. Butyltin species in PACS-1 were separated by cation exchange HPLC of an extract of the sediment; method detection limits for tributyltin and dibutyltin in sediment samples are estimated to be 5 ng Sn/g and 12 ng Sn/g, respectively. (orig.).

  8. The Simultaneous measurement of serum testosterone and 5α-dihydrotestosterone by gas chromatography-mass spectrometry (GC-MS).

    Science.gov (United States)

    Kannenberg, Frank; Fobker, Manfred; Schulte, Erhard; Pierściński, Grzegorz; Kelsch, Reinhard; Zitzmann, Michael; Nofer, Jerzy-Roch; Schüring, Andreas N

    2018-01-01

    Simultaneous measurement of testosterone (T) and 5α-dihydrotestosterone (DHT) is important for diagnosing androgen deficiency states and hyperandrogenism in males and females, respectively. However, immunoassays used for T and DHT determination suffer from inadequate specificity and sensitivity, while tandem mass spectrometry is expensive and demanding in use. We developed a selective gas chromatography-mass spectrometry (GC-MS) method for parallel T and DHT measurement. The assay showed a linear response up to 46.5nmol/L, intra- and interassay imprecision and inaccuracy 90% for both analytes. The limit of quantitation was 0.117nmol/L for T and 0.168nmol/L for DHT. Comparison with immunoassays revealed good agreement for T in males, but a bias in favour of immunoassays at low concentrations for T in females and DHT in both sexes. We established reference ranges for T and DHT and suggest interval partitioning for T according to age in men and menstrual cycle in women. Assay validation in a clinical setting suggests that measuring DHT or T/DHT ratio may help identify patients with polycystic ovary syndrome. We developed a selective, simple and inexpensive GC-MS method for parallel measurement of T and DHT with potential use in the clinical laboratory. Copyright © 2017 Elsevier B.V. All rights reserved.

  9. Mass-spectrometry analysis of histone post-translational modifications in pathology tissue using the PAT-H-MS approach

    Directory of Open Access Journals (Sweden)

    Roberta Noberini

    2016-06-01

    Full Text Available Aberrant histone post-translational modifications (hPTMs have been implicated with various pathologies, including cancer, and may represent useful epigenetic biomarkers. The data described here provide a mass spectrometry-based quantitative analysis of hPTMs from formalin-fixed paraffin-embedded (FFPE tissues, from which histones were extracted through the recently developed PAT-H-MS method. First, we analyzed FFPE samples from mouse spleen and liver or human breast cancer up to six years old, together with their corresponding fresh frozen tissue. We then combined the PAT-H-MS approach with a histone-focused version of the super-SILAC strategy-using a mix of histones from four breast cancer cell lines as a spike-in standard- to accurately quantify hPTMs from breast cancer specimens belonging to different subtypes. The data, which are associated with a recent publication (Pathology tissue-quantitative mass spectrometry analysis to profile histone post-translational modification patterns in patient samples (Noberini, 2015 [1], are deposited at the ProteomeXchange Consortium via the PRIDE partner repository with the dataset identifier http://www.ebi.ac.uk/pride/archive/projects/PXD002669.

  10. Determination of boron and lithium in diverse biological matrices using neutron activation-mass spectrometry (NA-MS)

    International Nuclear Information System (INIS)

    Iyengar, G.V.; Downing, R.G.; Clarke, W.B.

    1990-01-01

    Essential features of the neutron activation-mass Spectrometry (NA-MS) technique are described. Applicability of this technique for the simultaneous determination of boron and lithium is demonstrated for a diverse group of biomaterials. NA-MS is a nondestructive analytical technique, and dynamic in nature since its coverage extends to a broad range of concentration levels. Contamination after the irradiation step, extraneous by natural lithium or boron is inconsequential, since only the activation products are the analyted assayed. Coupling the nuclear activation phenomenon which generates 4 He and 3 He (from 10 B and 6 Li, respectively), with the high precision potential of mass spectrometry forms the bases of this technique. Under ideal conditions the detection limit is extendable to pg g -1 concentration ranges and therefore, it is extremely well suited to investigate the natural concentration levels of boron and lithium in biomaterials. The potential of this method for the determination of lithium in biomedical trace element research is of special significance since determination of sub-ppb levels of lithium by other analytical techniques faces serious analytical difficulties mainly due to contamination control and in some cases to insufficiently low detection limits. (orig.)

  11. Determination of 236U and transuranium elements in depleted uranium ammunition by α-spectrometry and ICP-MS

    International Nuclear Information System (INIS)

    Desideri, D.; Meli, M.A.; Roselli, C.; Testa, C.; Boulyga, S.F.; Becker, J.S.

    2002-01-01

    It is well known that ammunition containing depleted uranium (DU) was used by NATO during the Balkan conflict. To evaluate the origin of DU (the enrichment of natural uranium or the reprocessing of spent nuclear fuel) it is necessary to directly detect the presence of activation products ( 236 U, 239 Pu, 240 Pu, 241 Am, and 237 Np) in the ammunition. In this work the analysis of actinides by α-spectrometry was compared with that by inductively coupled plasma mass spectrometry (ICP-MS) after selective separation of ultratraces of transuranium elements from the uranium matrix. 242 Pu and 243 Am were added to calculate the chemical yield. Plutonium was separated from uranium by extraction chromatography, using tri-n-octylamine (TNOA), with a decontamination factor higher than 10 6 ; after elution plutonium was determined by ICP-MS ( 239 Pu and 240 Pu) and α-spectrometry ( 239+240 Pu) after electroplating. The concentration of Pu in two DU penetrator samples was 7 x 10 -12 g g -1 and 2 x 10 -11 g g -1 . The 240 Pu/ 239 Pu isotope ratio in one penetrator sample (0.12±0.04) was significantly lower than the 240 Pu/ 239 Pu ratios found in two soil samples from Kosovo (0.35±0.10 and 0.27±0.07). 241 Am was separated by extraction chromatography, using di(2-ethylhexyl)phosphoric acid (HDEHP), with a decontamination factor as high as 10 7 . The concentration of 241 Am in the penetrator samples was 2.7 x 10 -14 g g -1 and -15 g g -1 . In addition 237 Np was detected at ultratrace levels. In general, ICP-MS and α-spectrometry results were in good agreement.The presence of anthropogenic radionuclides ( 236 U, 239 Pu, 240 Pu, 241 Am, and 237 Np) in the penetrators indicates that at least part of the uranium originated from the reprocessing of nuclear fuel. Because the concentrations of radionuclides are very low, their radiotoxicological effect is negligible. (orig.)

  12. Determination of {sup 236}U and transuranium elements in depleted uranium ammunition by {alpha}-spectrometry and ICP-MS

    Energy Technology Data Exchange (ETDEWEB)

    Desideri, D.; Meli, M.A.; Roselli, C.; Testa, C. [General Chemistry Institute, Urbino University, Urbino (Italy); Boulyga, S.F.; Becker, J.S. [Central Department of Analytical Chemistry, Research Centre Juelich, Juelich (Germany)

    2002-11-01

    It is well known that ammunition containing depleted uranium (DU) was used by NATO during the Balkan conflict. To evaluate the origin of DU (the enrichment of natural uranium or the reprocessing of spent nuclear fuel) it is necessary to directly detect the presence of activation products ({sup 236}U, {sup 239}Pu, {sup 240}Pu, {sup 241}Am, and {sup 237}Np) in the ammunition. In this work the analysis of actinides by {alpha}-spectrometry was compared with that by inductively coupled plasma mass spectrometry (ICP-MS) after selective separation of ultratraces of transuranium elements from the uranium matrix. {sup 242}Pu and {sup 243}Am were added to calculate the chemical yield. Plutonium was separated from uranium by extraction chromatography, using tri-n-octylamine (TNOA), with a decontamination factor higher than 10{sup 6}; after elution plutonium was determined by ICP-MS ({sup 239}Pu and {sup 240}Pu) and {alpha}-spectrometry ({sup 239+240}Pu) after electroplating. The concentration of Pu in two DU penetrator samples was 7 x 10{sup -12} g g{sup -1} and 2 x 10{sup -11} g g{sup -1}. The {sup 240}Pu/{sup 239}Pu isotope ratio in one penetrator sample (0.12{+-}0.04) was significantly lower than the {sup 240}Pu/{sup 239}Pu ratios found in two soil samples from Kosovo (0.35{+-}0.10 and 0.27{+-}0.07). {sup 241}Am was separated by extraction chromatography, using di(2-ethylhexyl)phosphoric acid (HDEHP), with a decontamination factor as high as 10{sup 7}. The concentration of {sup 241}Am in the penetrator samples was 2.7 x 10{sup -14} g g{sup -1} and <9.4 x 10{sup -15} g g{sup -1}. In addition {sup 237}Np was detected at ultratrace levels. In general, ICP-MS and {alpha}-spectrometry results were in good agreement.The presence of anthropogenic radionuclides ({sup 236}U, {sup 239}Pu,{sup 240}Pu, {sup 241}Am, and {sup 237}Np) in the penetrators indicates that at least part of the uranium originated from the reprocessing of nuclear fuel. Because the concentrations of

  13. Determination of (236)U and transuranium elements in depleted uranium ammunition by alpha-spectrometry and ICP-MS.

    Science.gov (United States)

    Desideri, D; Meli, M A; Roselli, C; Testa, C; Boulyga, S F; Becker, J S

    2002-11-01

    It is well known that ammunition containing depleted uranium (DU) was used by NATO during the Balkan conflict. To evaluate the origin of DU (the enrichment of natural uranium or the reprocessing of spent nuclear fuel) it is necessary to directly detect the presence of activation products ((236)U, (239)Pu, (240)Pu, (241)Am, and (237)Np) in the ammunition. In this work the analysis of actinides by alpha-spectrometry was compared with that by inductively coupled plasma mass spectrometry (ICP-MS) after selective separation of ultratraces of transuranium elements from the uranium matrix. (242)Pu and (243)Am were added to calculate the chemical yield. Plutonium was separated from uranium by extraction chromatography, using tri- n-octylamine (TNOA), with a decontamination factor higher than 10(6); after elution plutonium was determined by ICP-MS ((239)Pu and (240)Pu) and alpha-spectrometry ((239+240)Pu) after electroplating. The concentration of Pu in two DU penetrator samples was 7 x 10(-12) g g(-1) and 2 x 10(-11) g g(-1). The (240)Pu/(239)Pu isotope ratio in one penetrator sample (0.12+/-0.04) was significantly lower than the (240)Pu/(239)Pu ratios found in two soil samples from Kosovo (0.35+/-0.10 and 0.27+/-0.07). (241)Am was separated by extraction chromatography, using di(2-ethylhexyl)phosphoric acid (HDEHP), with a decontamination factor as high as 10(7). The concentration of (241)Am in the penetrator samples was 2.7 x 10(-14) g g(-1) and <9.4 x 10(-15) g g(-1). In addition (237)Np was detected at ultratrace levels. In general, ICP-MS and alpha-spectrometry results were in good agreement. The presence of anthropogenic radionuclides ((236)U, (239)Pu,(240)Pu, (241)Am, and (237)Np) in the penetrators indicates that at least part of the uranium originated from the reprocessing of nuclear fuel. Because the concentrations of radionuclides are very low, their radiotoxicological effect is negligible.

  14. LC-MS-MS aboard ship: tandem mass spectrometry in the search for phycotoxins and novel toxigenic plankton from the North Sea.

    Science.gov (United States)

    Krock, Bernd; Tillmann, Urban; John, Uwe; Cembella, Allan

    2008-11-01

    Phycotoxins produced by various species of toxigenic microalgae occurring in the plankton are a global threat to the security of seafood resources and the health of humans and coastal marine ecosystems. This has necessitated the development and application of advanced methods in liquid chromatography coupled to mass spectrometry (LC-MS) for monitoring of these compounds, particularly in plankton and shellfish. Most such chemical analyses are conducted in land-based laboratories on stored samples, and thus much information on the near real-time biogeographical distribution and dynamics of phycotoxins in the plankton is unavailable. To resolve this problem, we conducted ship-board analysis of a broad spectrum of phycotoxins collected directly from the water column on an oceanographic cruise along the North Sea coast of Scotland, Norway, and Denmark. We equipped the ship with a triple-quadrupole linear ion-trap hybrid LC-MS-MS system for detection and quantitative analysis of toxins, such as domoic acid, gymnodimine, spirolides, dinophysistoxins, okadaic acid, pectenotoxins, yessotoxins, and azaspiracids (AZAs). We focused particular attention on the detection of AZAs, a group of potent nitrogenous polyether toxins, because the culprit species associated with the occurrence of these toxins in shellfish has been controversial. Marine toxins were analyzed directly from size-fractionated plankton net tows (20 microm mesh size) and Niskin bottle samples from discrete depths, after rapid methanolic extraction but without any further clean-up. Almost all expected phycotoxins were detected in North Sea plankton samples, with domoic acid and 20-methylspirolide G being most abundant. Although AZA was the least abundant of these toxins, the high sensitivity of the LC-MS-MS enabled detailed quantification, indicating that the highest amounts of AZA-1 were present in the southern Skagerrak in the 3-20 microm size-fraction. The direct on-board toxin measurements enabled isolation

  15. Gas chromatography coupled to atmospheric pressure ionization mass spectrometry (GC-API-MS): review.

    Science.gov (United States)

    Li, Du-Xin; Gan, Lin; Bronja, Amela; Schmitz, Oliver J

    2015-09-03

    Although the coupling of GC/MS with atmospheric pressure ionization (API) has been reported in 1970s, the interest in coupling GC with atmospheric pressure ion source was expanded in the last decade. The demand of a "soft" ion source for preserving highly diagnostic molecular ion is desirable, as compared to the "hard" ionization technique such as electron ionization (EI) in traditional GC/MS, which fragments the molecule in an extensive way. These API sources include atmospheric pressure chemical ionization (APCI), atmospheric pressure photoionization (APPI), atmospheric pressure laser ionization (APLI), electrospray ionization (ESI) and low temperature plasma (LTP). This review discusses the advantages and drawbacks of this analytical platform. After an introduction in atmospheric pressure ionization the review gives an overview about the history and explains the mechanisms of various atmospheric pressure ionization techniques used in combination with GC such as APCI, APPI, APLI, ESI and LTP. Also new developments made in ion source geometry, ion source miniaturization and multipurpose ion source constructions are discussed and a comparison between GC-FID, GC-EI-MS and GC-API-MS shows the advantages and drawbacks of these techniques. The review ends with an overview of applications realized with GC-API-MS. Copyright © 2015. Published by Elsevier B.V.

  16. Accurate quantification of 5 German cockroach (GCr) allergens in complex extracts using multiple reaction monitoring mass spectrometry (MRM MS).

    Science.gov (United States)

    Mindaye, S T; Spiric, J; David, N A; Rabin, R L; Slater, J E

    2017-12-01

    German cockroach (GCr) allergen extracts are complex and heterogeneous products, and methods to better assess their potency and composition are needed for adequate studies of their safety and efficacy. The objective of this study was to develop an assay based on liquid chromatography and multiple reaction monitoring mass spectrometry (LC-MRM MS) for rapid, accurate, and reproducible quantification of 5 allergens (Bla g 1, Bla g 2, Bla g 3, Bla g 4, and Bla g 5) in crude GCr allergen extracts. We first established a comprehensive peptide library of allergens from various commercial extracts as well as recombinant allergens. Peptide mapping was performed using high-resolution MS, and the peptide library was then used to identify prototypic and quantotypic peptides to proceed with MRM method development. Assay development included a systematic optimization of digestion conditions (buffer, digestion time, and trypsin concentration), chromatographic separation, and MS parameters. Robustness and suitability were assessed following ICH (Q2 [R1]) guidelines. The method is precise (RSD  0.99, 0.01-1384 fmol/μL), and sensitive (LLOD and LLOQ MS, we quantified allergens from various commercial GCr extracts and showed considerable variability that may impact clinical efficacy. Our data demonstrate that the LC-MRM MS method is valuable for absolute quantification of allergens in GCr extracts and likely has broader applicability to other complex allergen extracts. Definitive quantification provides a new standard for labelling of allergen extracts, which will inform patient care, enable personalized therapy, and enhance the efficacy of immunotherapy for environmental and food allergies. © 2017 The Authors. Clinical & Experimental Allergy published by John Wiley & Sons Ltd. This article has been contributed to by US Government employees and their work is in the public domain in the USA.

  17. Bioimaging mass spectrometry of trace elements – recent advance and applications of LA-ICP-MS: A review

    Energy Technology Data Exchange (ETDEWEB)

    Becker, J.Sabine, E-mail: s.becker@fz-juelich.de [Central Institute for Engineering, Electronics and Analytics (ZEA-3), Forschungszentrum Jülich, Jülich D-52425 (Germany); Matusch, Andreas, E-mail: a.matusch@fz-juelich.de [Institute for Neuroscience and Medicine (INM-2), Forschungszentrum Jülich, Jülich D-52425 (Germany); Wu, Bei, E-mail: b.wu@fz-juelich.de [Central Institute for Engineering, Electronics and Analytics (ZEA-3), Forschungszentrum Jülich, Jülich D-52425 (Germany)

    2014-07-04

    Highlights: • Bioimaging LA-ICP-MS is established for trace metals within biomedical specimens. • Trace metal imaging allows to study brain function and neurodegenerative diseases. • Laser microdissection ICP-MS was applied to mouse brain hippocampus and wheat root. - Abstract: Bioimaging using laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS) offers the capability to quantify trace elements and isotopes within tissue sections with a spatial resolution ranging about 10–100 μm. Distribution analysis adds to clarifying basic questions of biomedical research and enables bioaccumulation and bioavailability studies for ecological and toxicological risk assessment in humans, animals and plants. Major application fields of mass spectrometry imaging (MSI) and metallomics have been in brain and cancer research, animal model validation, drug development and plant science. Here we give an overview of latest achievements in methods and applications. Recent improvements in ablation systems, operation and cell design enabled progressively better spatial resolutions down to 1 μm. Meanwhile, a body of research has accumulated covering basic principles of the element architecture in animals and plants that could consistently be reproduced by several laboratories such as the distribution of Fe, Cu, Zn in rodent brain. Several studies investigated the distribution and delivery of metallo-drugs in animals. Hyper-accumulating plants and pollution indicator organisms have been the key topics in environmental science. Increasingly, larger series of samples are analyzed, may it be in the frame of comparisons between intervention and control groups, of time kinetics or of three-dimensional atlas approaches.

  18. Can we trust mass spectrometry for determination of arsenic peptides in plants: comparison of LC-ICP-MS and LC-ES-MS/ICP-MS with XANES/EXAFS in analysis of Thunbergia alata.

    Science.gov (United States)

    Bluemlein, Katharina; Raab, Andrea; Meharg, Andrew A; Charnock, John M; Feldmann, Jörg

    2008-04-01

    The weakest step in the analytical procedure for speciation analysis is extraction from a biological material into an aqueous solution which undergoes HPLC separation and then simultaneous online detection by elemental and molecular mass spectrometry (ICP-MS/ES-MS). This paper describes a study to determine the speciation of arsenic and, in particular, the arsenite phytochelatin complexes in the root from an ornamental garden plant Thunbergia alata exposed to 1 mg As L(-1) as arsenate. The approach of formic acid extraction followed by HPLC-ES-MS/ICP-MS identified different As(III)-PC complexes in the extract of this plant and made their quantification via sulfur (m/z 32) and arsenic (m/z 75) possible. Although sulfur sensitivity could be significantly increased when xenon was used as collision gas in ICP-qMS, or when HR-ICP-MS was used in medium resolution, the As:S ratio gave misleading results in the identification of As(III)-PC complexes due to the relatively low resolution of the chromatography system in relation to the variety of As-peptides in plants. Hence only the parallel use of ES-MS/ICP-MS was able to prove the occurrence of such arsenite phytochelatin complexes. Between 55 and 64% of the arsenic was bound to the sulfur of peptides mainly as As(III)(PC(2))(2), As(III)(PC(3)) and As(III)(PC(4)). XANES (X-ray absorption near-edge spectroscopy) measurement, using the freshly exposed plant root directly, confirmed that most of the arsenic is trivalent and binds to S of peptides (53% As-S) while 38% occurred as arsenite and only 9% unchanged as arsenate. EXAFS data confirmed that As-S and As-O bonds occur in the plants. This study confirms, for the first time, that As-peptides can be extracted by formic acid and chromatographically separated on a reversed-phase column without significant decomposition or de-novo synthesis during the extraction step.

  19. Two complementary liquid chromatography-tandem mass spectrometry (LC-MS/MS) methods to study the excretion and metabolic interaction of edaravone and taurine in rats.

    Science.gov (United States)

    Tang, Dao-quan; Zheng, Xiao-xiao; Li, Yin-jie; Bian, Ting-ting; Yu, Yan-yan; Du, Qian; Yang, Dong-zhi; Jiang, Shui-shi

    2014-11-01

    In this study, two independent and complementary liquid chromatography-tandem mass spectrometry (LC-MS/MS) methods were respectively developed and validated for the determination of edaravone or taurine in rat urine, feces and bile after intravenous administration, using 3-methyl-l-p-tolyl-5-pyrazolone and sulfanilic acid as the internal standards (IS). Edaravone was separated on an Agilent Eclipse Plus C18 column (100×2.1 mm, 3.5 μm) using methanol and water (containing 5 mM ammonium formate and 0.02% formic acid) as mobile phase, while taurine was performed on a Waters Atlantis HILIC Silica column (150×2.1 mm, 3 μm) using acetonitrile and water (containing 5mM ammonium formate and 0.2% formic acid) as mobile phase. The mass analysis was performed in a Triple Quadrupole mass spectrometer via multiple reaction monitoring (MRM) with negative ionization mode. The optimized mass transition ion pairs (m/z) for quantification were 173.1→92.2 and 187.2→106.0 for edaravone and its IS, 124.1→80.0 and 172.0→80.0 for taurine and its IS, respectively. The validated methods have been successfully applied to the excretion and metabolism interaction study of edaravone and taurine in rats after independent intravenous administration and co-administration with a single dose. The results demonstrated that there were no significant alternations on the metabolism and cumulative excretion rate of edaravone and taurine, implying that the proposed combination therapy was pharmacologically viable. Copyright © 2014 Elsevier B.V. All rights reserved.

  20. Simultaneous determination of multi-mycotoxins in palm kernel cake (PKC) using liquid chromatography-tandem mass spectrometry (LC-MS/MS).

    Science.gov (United States)

    Yibadatihan, S; Jinap, S; Mahyudin, N A

    2014-01-01

    Palm kernel cake (PKC) is a useful source of protein and energy for livestock. Recently, it has been used as an ingredient in poultry feed. Mycotoxin contamination of PKC due to inappropriate handling during production and storage has increased public concern about economic losses and health risks for poultry and humans. This concern has accentuated the need for the evaluation of mycotoxins in PKC. Furthermore, a method for quantifying mycotoxins in PKC has so far not been established. The aims of this study were therefore (1) to develop a method for the simultaneous determination of mycotoxins in PKC and (2) to validate and verify the method. A liquid chromatography-tandem mass spectrometry (LC-MS/MS) method using an electrospray ionisation interface (ESI) in both positive- and negative-ion modes was developed for the simultaneous determination of aflatoxins (AFB₁, AFB₂, AFG₁ and AFG₂), ochratoxin A (OTA), zearalenone (ZEA), deoxynivalenol (DON), fumonisins (FB₁ and FB₂), T-2 and HT-2 toxin in PKC. An optimum method using a 0.2 ml min⁻¹ flow rate, 0.2% formic acid in aqueous phase, 10% organic phase at the beginning and 90% organic phase at the end of the gradient was achieved. The extraction of mycotoxins was performed using a solvent mixture of acetonitrile-water-formic acid (79:20:1, v/v) without further clean-up. The mean recoveries of mycotoxins in spiked PKC samples ranged from 81% to 112%. Limits of detection (LODs) and limits of quantification (LOQs) for mycotoxin standards and PKC samples ranged from 0.02 to 17.5 μg kg⁻¹ and from 0.06 to 58.0 μg kg⁻¹, respectively. Finally, the newly developed method was successfully applied to PKC samples. The results illustrated the fact that the method is efficient and accurate for the simultaneous multi-mycotoxin determination in PKC, which can be ideal for routine analysis.

  1. Measurement of tissue azithromycin levels in self-collected vaginal swabs post treatment using liquid chromatography and tandem mass spectrometry (LC-MS/MS.

    Directory of Open Access Journals (Sweden)

    Lenka A Vodstrcil

    Full Text Available Azithromycin is recommended for the treatment of uncomplicated urogenital chlamydia infection although the standard 1gram dose sometimes fails to eradicate the infection (treatment failure. One hypothesis proposed for treatment failure has been insufficient levels of the antibiotic at the site of infection. We developed an assay using liquid chromatography and tandem mass spectrometry (LC-MS/MS to measure azithromycin concentration in high-vaginal swabs and monitor how concentration changes over time following routine azithromycin treatment.Azithromycin concentrations were measured in two groups of women either within the first 24h of taking a 1g dose (N = 11 or over 9 days (N = 10. Azithromycin concentrations were normalised to an internal standard (leucine enkephalin, and the bulk lipid species phosphatidylcholine [PC(34:1], using an Agilent 6490 triple quadrupole instrument in positive ionisation mode. The abundances of azithromycin, PC(34:1, and leu-enkephalin were determined by multiple reaction monitoring and absolute levels of azithromycin estimated using standard curves prepared on vaginal specimens.Vaginal azithromycin concentrations of women were rapidly obtained after 5h post-treatment (mean concentration = 1031mcg/mg of lipid, range = 173-2693mcg/mg. In women followed for 9 days, peak concentrations were highest after day 2 (mean concentration = 2206mcg/mg, range = 721-5791mcg/mg, and remained high for at least 9 days with a mean concentration of 384mcg/mg (range = 139-1024mcg/mg on day 9.Our study confirmed that a single 1g dose of azithromycin is rapidly absorbed and remains in the vagina at relatively high levels for at least a week, suggesting that poor antibiotic absorption is unlikely to be an explanation for treatment failure.

  2. Food Safety is an Important Public Health Issue: Chloramphenicol Residues Determination by Liquid Chromatography Tandem Mass Spectrometry (LC-MS/MS) in honey.

    Science.gov (United States)

    Krivohlavek, Adela; Žuntar, Irena; Ivešić, Martina; Andačić, Ivana Mandić; Šikić, Sandra

    2014-12-01

    Honey is used for nutritional, medicinal and industrial purposes and antibiotic residues may harm its quality and constitute a danger to human health. The broad spectrum antibiotic chloramphenicol (CAP) was used for curative purposes in veterinary medicine, but is now forbidden in European Union (EU) because of its many serious side effects (e.g. aplastic anaemia, grey syndrome, severe bone marrow depression and hypersensitivity). The aim of this study was to facilitate analyses of the quality and safety of Croatian honey distributed to whole European Union market; an assessment that has not previously been made. CAP in honey was qualifying and quantifying by validated liquid chromatography tandem mass spectrometry with negative electrospray ionisation method (LC-MS/MS). The target antibiotic was separated on chromatographic column Zorbax SB C18 (150 mm x 2.1 mm, 3.5 μm) with a gradient elution using acetonitrile - 0.1% formic acid mobile phase at a flow rate of 0.3 mL/min, with column temperature 35°C for CAP and 5D-CAP as internal standard. Homogenised honey samples were diluted with acetate buffer solution and extracted on Oasis Hydrophilic-Lipophilic-Balanced (HLB) sorbents. The method was used to analyse 280 domestic honey samples collected throughout Croatia between 2005.-2013. Recoveries of the method for real (acacia, chestnut, linden and flower) honey samples were 102% with RSD 8.4%. The value CCα and CCβ were 0.09 and 0.12 μg/kg, respectively. Results showed only three subsequent positive detections (1.1%) of CAP in honey. Analysed honey samples from Croatia showed good quality and safety what is the one of the main objective in consumer health policy in EU.

  3. Computer-aided method for identification of major flavone/flavonol glycosides by high-performance liquid chromatography-diode array detection-tandem mass spectrometry (HPLC-DAD-MS/MS).

    Science.gov (United States)

    Wang, Zhengfang; Lin, Longze; Harnly, James M; Harrington, Peter de B; Chen, Pei

    2014-11-01

    A new computational tool is proposed here for tentatively identifying major (UV quantifiable) flavone/flavonol glycoside peaks of high performance liquid chromatogram (HPLC)-diode array detection (DAD)-tandem mass spectrometry (MS/MS) profiles based on a MATLAB-based script implementing an in-house algorithm. The HPLC-DAD-MS/MS profiles of red onion, Chinese lettuce, carrot leaf, and celery seed extracts were analyzed by the proposed computer-aided screening method for identifying possible flavone/flavonol glycoside peaks from the HPLC-UV and MS total ion current (TIC) chromatograms. The number of identified flavone/flavonol glycoside peaks of the HPLC-UV chromatograms is four, four, six, and nine for red onion, Chinese lettuce, carrot leaf, and celery seed, respectively. These results have been validated by human(s) experts. For the batch processing of nine HPLC-DAD-MS/MS profiles of celery seed extract, the entire script execution time was within 15 s while manual calculation of only one HPLC-DAD-MS/MS profile by a flavonoid expert could take hours. Therefore, this MATLAB-based screening method is able to facilitate the HPLC-DAD-MS/MS analysis of flavone/flavonol glycosides in plants to a large extent.

  4. BioSunMS: a plug-in-based software for the management of patients information and the analysis of peptide profiles from mass spectrometry

    Directory of Open Access Journals (Sweden)

    Zhang Xuemin

    2009-02-01

    Full Text Available Abstract Background With wide applications of matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS and surface-enhanced laser desorption/ionization time-of-flight mass spectrometry (SELDI-TOF MS, statistical comparison of serum peptide profiles and management of patients information play an important role in clinical studies, such as early diagnosis, personalized medicine and biomarker discovery. However, current available software tools mainly focused on data analysis rather than providing a flexible platform for both the management of patients information and mass spectrometry (MS data analysis. Results Here we presented a plug-in-based software, BioSunMS, for both the management of patients information and serum peptide profiles-based statistical analysis. By integrating all functions into a user-friendly desktop application, BioSunMS provided a comprehensive solution for clinical researchers without any knowledge in programming, as well as a plug-in architecture platform with the possibility for developers to add or modify functions without need to recompile the entire application. Conclusion BioSunMS provides a plug-in-based solution for managing, analyzing, and sharing high volumes of MALDI-TOF or SELDI-TOF MS data. The software is freely distributed under GNU General Public License (GPL and can be downloaded from http://sourceforge.net/projects/biosunms/.

  5. Investigation of mercury-containing proteins by enriched stable isotopic tracer and size-exclusion chromatography hyphenated to inductively coupled plasma-isotope dilution mass spectrometry

    Energy Technology Data Exchange (ETDEWEB)

    Shi Junwen [Laboratory for Bio-Environmental Health Sciences of Nanoscale Materials and Key Laboratory of Nuclear Analytical Techniques, Institute of High Energy Physics, Chinese Academy of Sciences, Beijing 100049 (China)]|[Graduate School of the Chinese Academy of Sciences, Beijing 100049 (China); Feng Weiyue [Laboratory for Bio-Environmental Health Sciences of Nanoscale Materials and Key Laboratory of Nuclear Analytical Techniques, Institute of High Energy Physics, Chinese Academy of Sciences, Beijing 100049 (China)]. E-mail: fengwy@mail.ihep.ac.cn; Wang Meng [Laboratory for Bio-Environmental Health Sciences of Nanoscale Materials and Key Laboratory of Nuclear Analytical Techniques, Institute of High Energy Physics, Chinese Academy of Sciences, Beijing 100049 (China)]|[Graduate School of the Chinese Academy of Sciences, Beijing 100049 (China); Zhang Fang [Graduate School of the Chinese Academy of Sciences, Beijing 100049 (China); Li Bai [Laboratory for Bio-Environmental Health Sciences of Nanoscale Materials and Key Laboratory of Nuclear Analytical Techniques, Institute of High Energy Physics, Chinese Academy of Sciences, Beijing 100049 (China); Wang Bing; Zhu Motao [Laboratory for Bio-Environmental Health Sciences of Nanoscale Materials and Key Laboratory of Nuclear Analytical Techniques, Institute of High Energy Physics, Chinese Academy of Sciences, Beijing 100049 (China)]|[Graduate School of the Chinese Academy of Sciences, Beijing 100049 (China); Chai Zhifang [Laboratory for Bio-Environmental Health Sciences of Nanoscale Materials and Key Laboratory of Nuclear Analytical Techniques, Institute of High Energy Physics, Chinese Academy of Sciences, Beijing 100049 (China)]|[Institute of Nuclear Technology, Shenzhen University, Shenzhen 518060 (China)]|[Institute of Nanochemistry and Nanosafety, Shanghai University, Shanghai (China)

    2007-01-30

    In order to investigate trace mercury-containing proteins in maternal rat and their offspring, a method of enriched stable isotopic tracer ({sup 196}Hg and {sup 198}Hg) combined with size-exclusion chromatography (SEC) coupled to inductively coupled plasma-isotope dilution mass spectrometry (ICP-IDMS) was developed. Prior to the analysis, {sup 196}Hg- and {sup 198}Hg-enriched methylmercury was administrated to the pregnant rats. Then the mercury-containing proteins in serum and brain cytosol of the dam and pup rats were separated by size-exclusion columns and the mercury was detected by ICP-MS. The ICP-MS spectrogram of the tracing samples showed significantly elevated {sup 196}Hg and {sup 198}Hg isotopic signals compared with the natural ones, indicating that the detection sensitivity could be increased by the tracer method. The contents of mercury in chromatographic fractions of the dam and pup rat brain cytosol were quantitatively estimated by post-column reverse ID-ICP-MS. The quantitative speciation differences of mercury in brain cytosol between the dam and pup rats were observed, indicating that such studies could be useful for toxicological estimation. Additionally, the isotopic ratio measurement of {sup 198}Hg/{sup 202}Hg in the tracing samples could be used to identify the artifact mercury species caused in the analytical procedure. The study demonstrates that the tracer method combined with high-performance liquid chromatography (HPLC)-ICP-IDMS could provide reliably qualitative and quantitative information on mercury-containing proteins in organisms.

  6. Chemical speciation of arsenic species in human blood serum by liquid chromatography using a phosphatidylcholine-coated ODS column with detection by ICP-MS

    International Nuclear Information System (INIS)

    Hasegawa, Takuya; Ishise, Jotaro; Fukumoto, Yasuharu; Matsuura, Hirotaka; Zhu, Yanbei; Umemura, Tomonari; Haraguchi, Hiroki; Yamamoto, Kazuhito; Naoe, Tomoki

    2007-01-01

    Chemical speciation of arsenic species in human blood serum was performed by high-performance liquid chromatography/inductively coupled plasma mass spectrometry (HPLC/ICP-MS) with direct sample injection, where an octadecylsilyl silica (ODS) column coated with phosphatidylcholine (PC) (hereafter known as 'PC-coated ODS column') was used as the separation column. In arsenic species analysis, a citrate buffer solution (pH 4.0) was used as the mobile phase, in which the following reagents were added: sodium 1-dodecanesulfonate (SDS), tetramethylammonium hydroxide (TMAH), which are ion-pair reagents to separate inorganic and organic arsenic species, and 3-[(3-cholamidopropyl)-dimethylammonio]-1-propane sulfonate (CHAPS), which is a protein-solubilizing agent to prevent adsorption of proteins on the column. As a result of optimization, five representative arsenic species spiked in human blood serum reference material could be separated from each other within 5 min on the PC-coated ODS column by elution with a 5 mM citrate buffer (pH 4.0) containing 5 mM SDS, 5 mM THAH, and 0.2 mM CHAPS. The detection limits obtained by ICP-MS were 3.1, 2.7, 4.5, 2.5, and 2.5 ng of As g -1 for arsenate (iAs V ), arsenite (iAs III ), monomethylarsonic acid (MMA), dimethylarsenic acid (DMA), and arsenobetaine (AB), respectively, when the injection volume was 20 μL. The present separation system was also applied to speciation analysis of arsenic species in human blood serum collected from a leukemia patient after therapeutic treatment with arsenic. (author)

  7. Determination of 241Am in sediments by isotope dilution high resolution inductively coupled plasma mass spectrometry (ID HR ICP-MS).

    Science.gov (United States)

    Agarande, M; Benzoubir, S; Bouisset, P; Calmet, D

    2001-08-01

    Trace levels (pg kg(-1)) of 241Am in sediments were determined by isotope dilution high resolution inductively coupled plasma mass spectrometry (ID HR ICP-MS) using a microconcentric nebulizer. 241Am was isolated from major elements like Ca and Fe by different selective precipitations. In further steps. Am was first separated from other transuranic elements and purified by anion exchange and extraction chromatography prior to the mass spectrometric measurements. The ID HR ICP-MS results are compared with isotope dilution alpha spectrometry.

  8. Characterization of Two Different Clay Materials by Thermogravimetry (TG), Differential Scanning Calorimetry (DSC), Dilatometry (DIL) and Mass Spectrometry (MS) - 12215

    Energy Technology Data Exchange (ETDEWEB)

    Post, Ekkehard [NETZSCH Geraetebau GmbH, Wittelsbacherstrasse 42, 95100 Selb (Germany); Henderson, Jack B. [NETZSCH Instruments North America, LLC, 129 Middlesex Turnpike, Burlington, MA 01803 (United States)

    2012-07-01

    An illitic clay containing higher amounts of organic materials was investigated by dilatometry, thermogravimetry and differential scanning calorimetric. The evolved gases were studied during simultaneous TG-DSC (STA) and dilatometer measurements with simultaneous mass spectrometry in inert gas and oxidizing atmosphere. The dilatometer results were compared with the STA-MS results which confirmed and explained the reactions found during heating of the clay, like dehydration, dehydroxylation, shrinkage, sintering, quartz phase transition, combustion or pyrolysis of organics and the solid state reactions forming meta-kaolinite and mullite. The high amount of organic material effects in inert gas atmosphere most probably a reduction of the oxides which leads to a higher mass loss than in oxidizing atmosphere. Due to this reduction an additional CO{sub 2} emission at around 1000 deg. C was detected which did not occur in oxidizing atmosphere. Furthermore TG-MS results of a clay containing alkali nitrates show that during heating, in addition to water and CO{sub 2}, NO and NO{sub 2} are also evolved, leading to additional mass loss steps. These types of clays showed water loss starting around 100 deg. C or even earlier. This relative small mass loss affects only less shrinkage during the expansion of the sample. The dehydroxylation and the high crystalline quartz content result in considerable shrinkage and expansion of the clay. During the usual solid state reaction where the clay structure collapses, the remaining material finally shrinks down to a so-called clinker. With the help of MS the TG steps can be better interpreted as the evolved gases are identified. With the help of the MS it is possible to distinguish between CO{sub 2} and water (carbonate decomposition, oxidation of organics or dehydration/dehydroxylation). The MS also clearly shows that mass number 44 is found during the TG step of the illitic clay at about 900 deg. C in inert gas, which was interpreted

  9. Spectrochemical pure cerium dioxide preparation and its quality control by inductively coupled plasma and mass spectrometry (ICP/MS)

    International Nuclear Information System (INIS)

    Da Silva Queiroz, C.A.; De Souza, J.E.; Abrao, A.

    1998-01-01

    Full text: A simple and economic procedure for the purification until 500 g CeO 2 batch is presented. The purified material will be used as spectrochemical standard. It is obtained by association of the fractional precipitation technique in the system REC 3 /H 2 O 2 /NH 4 OH to enrich the cerium up to 90% and then refined by ion exchange up to 99.9% CeO2. The 99,9% CeO 2 warranty control of purity was accomplished by inductively coupled plasma and mass spectrometry (ICP/ MS) and compared with activation analysis data, exhibiting impurities traces of same values of the international spec pure standard. The following results (average values) for the contaminant rare earths are (ppm):La(36), Pr(19), Nd(161), Sm(11), Eu(5,3),Gd(113),Tb(89),Dy(2),Ho(0.05),Er(1), Tm(0), Yb(11), Lu (19) and Y(2.1), respectively

  10. Independent assessment of matrix-assisted laser desorption/ionization mass spectrometry (MALDI-MS) sample preparation quality : Effect of sample preparation on MALDI-MS of synthetic polymers

    NARCIS (Netherlands)

    Kooijman, Pieter C.; Kok, Sander; Honing, Maarten

    2017-01-01

    Rationale: Matrix-assisted laser desorption/ionization mass spectrometry (MALDI-MS) provides detailed and in-depth information about the molecular characteristics of synthetic polymers. To obtain the most accurate results the sample preparation parameters should be chosen to suit the sample and the

  11. Radiochemical separation of actinides from environmental samples for determination with DF-ICP-MS and alpha spectrometry

    International Nuclear Information System (INIS)

    Ayranov, M.; Kraehenbuehl, U.; Sahli, H.; Roellin, S.; Burger, M.

    2005-01-01

    The purpose of this study was to develop an optimised sample preparation method for the determination of Pu, Am, and Cm in environmental samples, soils, and sediments, and to compare the sensitivities of DF-ICP-MS, alpha spectrometry, and liquid scintillation alpha spectrometry. Borate fusion was used for sample material digestion. Two methods based on TOPO liquid-liquid extraction and combination of TEVA and TRU extraction chromatography showed highest yields of 92.7% for Pu, 86.8% for Am, and 87.6% for Cm. The detection limits were between 0.014-0.034 Bq/kg for 239 Pu, 0.014-0.093 Bq/kg for 240 Pu, and 0.011-1.20 Bq/kg for 241 Am. Analytical results for 238 Pu, 239 Pu, 240 Pu, 241 Pu and 241 Am and their isotope ratios in certified reference materials (IAEA-135 and IAEA-300) indicated very good accuracy of the methods proposed. (orig.)

  12. Direct Visualization of Neurotransmitters in Rat Brain Slices by Desorption Electrospray Ionization Mass Spectrometry Imaging (DESI - MS)

    Science.gov (United States)

    Fernandes, Anna Maria A. P.; Vendramini, Pedro H.; Galaverna, Renan; Schwab, Nicolas V.; Alberici, Luciane C.; Augusti, Rodinei; Castilho, Roger F.; Eberlin, Marcos N.

    2016-12-01

    Mass spectrometry imaging (MSI) of neurotransmitters has so far been mainly performed by matrix-assisted laser desorption/ionization (MALDI) where derivatization reagents, deuterated matrix and/or high resolution, or tandem MS have been applied to circumvent problems with interfering ion peaks from matrix and from isobaric species. We herein describe the application of desorption electrospray ionization mass spectrometry imaging (DESI)-MSI in rat brain coronal and sagittal slices for direct spatial monitoring of neurotransmitters and choline with no need of derivatization reagents and/or deuterated materials. The amino acids γ-aminobutyric (GABA), glutamate, aspartate, serine, as well as acetylcholine, dopamine, and choline were successfully imaged using a commercial DESI source coupled to a hybrid quadrupole-Orbitrap mass spectrometer. The spatial distribution of the analyzed compounds in different brain regions was determined. We conclude that the ambient matrix-free DESI-MSI is suitable for neurotransmitter imaging and could be applied in studies that involve evaluation of imbalances in neurotransmitters levels.

  13. SFC-APLI-(TOF)MS: Hyphenation of Supercritical Fluid Chromatography to Atmospheric Pressure Laser Ionization Mass Spectrometry.

    Science.gov (United States)

    Klink, Dennis; Schmitz, Oliver Johannes

    2016-01-05

    Atmospheric-pressure laser ionization mass spectrometry (APLI-MS) is a powerful method for the analysis of polycyclic aromatic hydrocarbon (PAH) molecules, which are ionized in a selective and highly sensitive way via resonance-enhanced multiphoton ionization. APLI was presented in 2005 and has been hyphenated successfully to chromatographic separation techniques like high performance liquid chromatography (HPLC) and gas chromatography (GC). In order to expand the portfolio of chromatographic couplings to APLI, a new hyphenation setup of APLI and supercritical-fluid chromatography (SFC) was constructed and aim of this work. Here, we demonstrate the first hyphenation of SFC and APLI in a simple designed way with respect to different optimization steps to ensure a sensitive analysis. The new setup permits qualitative and quantitative determination of native and also more polar PAH molecules. As a result of the altered ambient characteristics within the source enclosure, the quantification of 1-hydroxypyrene (1-HP) in human urine is possible without prior derivatization. The limit of detection for 1-HP by SFC-APLI-TOF(MS) was found to be 0.5 μg L(-1), which is lower than the 1-HP concentrations found in exposed persons.

  14. Multi-elemental analysis of aqueous geochemical samples by quadrupole inductively coupled plasma-mass spectrometry (ICP-MS)

    Science.gov (United States)

    Wolf, Ruth E.; Adams, Monique

    2015-01-01

    Typically, quadrupole inductively coupled plasma-mass spectrometry (ICP-MS) is used to determine as many as 57 major, minor, and trace elements in aqueous geochemical samples, including natural surface water and groundwater, acid mine drainage water, and extracts or leachates from geological samples. The sample solution is aspirated into the inductively coupled plasma (ICP) which is an electrodeless discharge of ionized argon gas at a temperature of approximately 6,000 degrees Celsius. The elements in the sample solution are subsequently volatilized, atomized, and ionized by the ICP. The ions generated are then focused and introduced into a quadrupole mass filter which only allows one mass to reach the detector at a given moment in time. As the settings of the mass analyzer change, subsequent masses are allowed to impact the detector. Although the typical quadrupole ICP-MS system is a sequential scanning instrument (determining each mass separately), the scan speed of modern instruments is on the order of several thousand masses per second. Consequently, typical total sample analysis times of 2–3 minutes are readily achievable for up to 57 elements.

  15. Determination of tetrahydrozoline in urine and blood using gas chromatography-mass spectrometry (GC-MS).

    Science.gov (United States)

    Peat, Judy; Garg, Uttam

    2010-01-01

    Tetrahydrozoline, a derivative of imidazoline, is widely used for the symptomatic relief of conjunctival and nasal congestion; however, intentional or unintentional high doses can result in toxicity manifested by hypotension, tachycardia, and CNS depression. The detection of the drug in blood and urine is helpful in the diagnosis and management of a toxic patient. For the analysis, plasma, serum, or urine is added to a tube containing alkaline buffer and organic extraction solvents, and tetrahydrozoline from the sample is extracted into the organic phase by gentle mixing. After centrifugation, the upper organic solvent layer containing the drug is removed and dried under stream of nitrogen at 40 degrees C. The residue is reconstituted in a hexane-ethanol mixture and analyzed using gas-chromatography-mass spectrometry. Quantitation of the drug is done by comparing responses of unknown sample to the responses of the calibrators using selected ion monitoring. Naphazoline is used as an internal standard.

  16. Quality control of meat using proton-transfer-reaction-mass-spectrometry (PTR-MS)

    International Nuclear Information System (INIS)

    Mayr, D.; Hartungen, E.; Maerk, T.D.; Margesin, R.; Schinner, F.

    2002-01-01

    Full text: Numerous food scandals which happened during the last few years make food safety controls more and more important. The method currently used for determining the status of meat, with respect to spoilage, is analysis of the counts of total viable bacteria and/or specific spoilage bacteria. An obvious drawback of this bacteriological method is the long incubation period of 1-3 days that is required for colony formation. Therefore we develop a novel method for meat quality control using PTR-MS which does not have this drawback. We measured the emitted volatile organic compounds (VOCs) of meat (beef and pork) using PTR-MS as a function of storage time. At the same time a bacteriological examination of these meat samples was carried out. We found strong correlations (about 99 %) between some VOCs and bacteriological contamination. This is a first step to replace the time-consuming bacteriological method by fast headspace air measurements to facilitate the investigation of a huge number of pieces of meat in very short time and to determine the maximum storage time and storage temperature from the emissions. We will also use this method to investigate the growth of various bacteria, the changes in the microbial composition and the influence of various environmental conditions such as temperature, pH, chemical and microbial preservation techniques. (author)

  17. Determination of phenobarbital in hair matrix by liquid phase microextraction (LPME) and gas chromatography-mass spectrometry (GC-MS).

    Science.gov (United States)

    Roveri, Flávia Lopes; Paranhos, Beatriz Aparecida Passos Bismara; Yonamine, Mauricio

    2016-08-01

    A method for identification and quantification of phenobarbital in hair samples by liquid phase microextraction (LPME) and gas chromatography-mass spectrometry (GC-MS) has been presented. Drug-free hair specimens were collected and separated in 50mg aliquots. Each aliquot was washed with 2.0mL of dichloromethane for 15min at 37°C. Standards and deuterated internal standards for calibration and quality control samples were added to the washed hair aliquot and the sample was submitted to complete digestion with sodium hydroxide (NaOH) 1.0mol/L for 15min at 70°C. The dissolved sample was submitted to LPME. After extraction, the residue was derivatized with tetramethylammonium hydroxide (TMAH) and analyzed by GC-MS. The limit of detection (LOD) was 0.1ng/mg and the limit of quantification (LOQ) was 0.25ng/mg. The calibration curve was linear over a concentration range of 0.25ng/mg to 10ng/mg (r(2)>0.99). The intra- and inter-assay precisions, given by RSD, were less than 6% for phenobarbital. Fortified samples of secobarbital and pentobarbital were also submitted to the validated method. The method was successfully applied to hair samples collected from three volunteers who reported regular use of phenobarbital (clinical treatment). The concentrations found were 9.5, 15.1 and 16.3ng/mg of phenobarbital. To contemplate the concentrations found, dilution integrity tests were also validated. The LPME and GC-MS method showed to be suitable for the detection of phenobarbital in hair samples and can be promptly used for different purposes whenever required. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

  18. LC-MS/MS Tandem Mass Spectrometry for Analysis of Phenolic Compounds and Pentacyclic Triterpenes in Antifungal Extracts of Terminalia brownii (Fresen

    Directory of Open Access Journals (Sweden)

    Enass Y. A. Salih

    2017-12-01

    Full Text Available Decoctions and macerations of the stem bark and wood of Terminalia brownii Fresen. are used in traditional medicine for fungal infections and as fungicides on field crops and in traditional granaries in Sudan. In addition, T. brownii water extracts are commonly used as sprays for protecting wooden houses and furniture. Therefore, using agar disc diffusion and macrodilution methods, eight extracts of various polarities from the stem wood and bark were screened for their growth-inhibitory effects against filamentous fungi commonly causing fruit, vegetable, grain and wood decay, as well as infections in the immunocompromised host. Ethyl acetate extracts of the stem wood and bark gave the best antifungal activities, with MIC values of 250 µg/mL against Nattrassia mangiferae and Fusarium verticillioides, and 500 µg/mL against Aspergillus niger and Aspergillus flavus. Aqueous extracts gave almost as potent effects as the ethyl acetate extracts against the Aspergillus and Fusarium strains, and were slightly more active than the ethyl acetate extracts against Nattrassia mangiferae. Thin layer chromatography, RP-HPLC-DAD and tandem mass spectrometry (LC-MS/MS, were employed to identify the chemical constituents in the ethyl acetate fractions of the stem bark and wood. The stem bark and wood were found to have a similar qualitative composition of polyphenols and triterpenoids, but differed quantitatively from each other. The stilbene derivatives, cis- (3 and trans- resveratrol-3-O-β-galloylglucoside (4, were identified for the first time in T. brownii. Moreover, methyl-(S-flavogallonate (5, quercetin-7-β-O-di-glucoside (8, quercetin-7-O-galloyl-glucoside (10, naringenin-4′-methoxy-7-pyranoside (7, 5,6-dihydroxy-3′,4′,7-tri-methoxy flavone (12, gallagic acid dilactone (terminalin (6, a corilagin derivative (9 and two oleanane type triterpenoids (1 and (2 were characterized. The flavonoids, a corilagin derivative and terminalin, have not been

  19. Quantitative Analysis of Bisphenol A Leached from Household Plastics by Solid-Phase Microextraction and Gas Chromatography-Mass Spectrometry (SPME-GC-MS)

    Science.gov (United States)

    Johnson, Bettie Obi; Burke, Fernanda M.; Harrison, Rebecca; Burdette, Samantha

    2012-01-01

    The measurement of trace levels of bisphenol A (BPA) leached out of household plastics using solid-phase microextraction (SPME) with gas chromatography-mass spectrometry (GC-MS) is reported here. BPA is an endocrine-disrupting compound used in the industrial manufacture of polycarbonate plastic bottles and epoxy resin can liners. This experiment…

  20. A longitudinal study of methanol in the exhaled breath of 30 healthy volunteers using selected ion flow tube mass spectrometry, SIFT-MS

    Czech Academy of Sciences Publication Activity Database

    Turner, C.; Španěl, Patrik; Smith, D.

    2006-01-01

    Roč. 27, č. 7 (2006), s. 637-648 ISSN 0967-3334 Institutional research plan: CEZ:AV0Z40400503 Keywords : SIFT-MS * mass spectrometry * methanol Subject RIV: CF - Physical ; Theoretical Chemistry Impact factor: 1.438, year: 2006

  1. APPLICATION OF LIQUID-CHROMATOGRAPHY COMBINED WITH MASS-SPECTROMETRY (LC-MS) TO ESTABLISH IDENTITY AND PURITY OF PET-RADIOPHARMACEUTICALS

    NARCIS (Netherlands)

    FRANSSEN, EJF; LUURTSEMA, G; MEDEMA, J; VISSER, GM; JERONISMUSSHALINGH, CM; BRUINS, AP; VAALBURG, W

    This article describes the application of liquid chromatography combined with mass-spectrometry (LC-MS) as a new quality control tool for PET-radiopharmaceuticals. The final step in the production of 2-[F-18]fluoro-2-deoxy-D-glucose (F-18-FDG) is a purification by HPLC. This procedure was validated

  2. Analysis of Phospholipid Mixtures from Biological Tissues by Matrix-Assisted Laser Desorption and Ionization Time-of-Flight Mass Spectrometry (MALDI-TOF MS): A Laboratory Experiment

    Science.gov (United States)

    Eibisch, Mandy; Fuchs, Beate; Schiller, Jurgen; Sub, Rosmarie; Teuber, Kristin

    2011-01-01

    Matrix-assisted laser desorption and ionization time-of-flight mass spectrometry (MALDI-TOF MS) is increasingly used to investigate the phospholipid (PL) compositions of tissues and body fluids, often without previous separation of the total mixture into the individual PL classes. Therefore, the questions of whether all PL classes are detectable…

  3. A gas chromatography-mass spectrometry (GC-MS) method for the detection and quantitation of monofluoroacetate in plants toxic to livestock

    Science.gov (United States)

    Monofluoroacetate (MFA) is a potent toxin that occurs in over 50 plant species in Africa, Australia, and South America and is responsible for significant livestock deaths in these regions. A gas chromatography–mass spectrometry (GC-MS) method for the analysis of MFA in plants based on the derivatiza...

  4. DATA TRANSFER FROM A DEC PDP-11 BASED MASS-SPECTROMETRY DATA STATION TO AN MS-DOS PERSONAL-COMPUTER

    NARCIS (Netherlands)

    RAFFAELLI, A; BRUINS, AP

    This paper describes a simple procedure for obtaining better quality graphic output for mass spectrometry data from data systems equipped with poor quality printing devices. The procedure uses KERMIT, a low cost public domain software, to transfer ASCII tables to a MS-DOS personal computer where

  5. Differentiation of Clinically Relevant mucorales Rhizopus microsporus and R. arrhizus by Matrix-Assisted Laser Desorption Ionization-Time of Flight Mass Spectrometry (MALDI-TOF MS)

    NARCIS (Netherlands)

    Dolatabadi, S.; Kolecka, A.; Versteeg, Matthijs; de Hoog, Sybren G; Boekhout, Teun

    This study addresses the usefulness of Matrix-Assisted Laser Desorption Ionization-Time of Flight Mass Spectrometry (MALDI-TOF MS) for reliable identification of the two most frequently occuring clinical species of Rhizopus, namely R. arrhizus with its two varieties arrhizus and delemar and R.

  6. High-resolution line-scan analysis of resin-embedded sediments using laser ablation-inductively coupled plasma-mass spectrometry (LA-ICP-MS)

    NARCIS (Netherlands)

    Hennekam, Rick; Jilbert, Tom; Mason, Paul R D; de Lange, Gert J.; Reichart, Gert Jan

    2015-01-01

    Laser ablation-inductively coupled plasma-mass spectrometry (LA-ICP-MS) line-scanning is a promising technique for producing high-resolution (μm-scale) geochemical records on resin-embedded sediments. However, this approach has not yet been thoroughly tested on sediment samples of known elemental

  7. DIFFERENTIATION OF AEROMONAS ISOLATES OBTAINED FROM DRINKING WATER DISTRIBUTION SYSTEM USING MATRIX-ASSISTED LASER DESCRIPTION/IONIZATION-MASS SPECTROMETRY (MALDI-MS)

    Science.gov (United States)

    The genus Aeromonas is one of several medically significant genera that have gained prominence due to their evolving taxonomy and controversial role in human diseases. In this study, matrix-assisted laser desorption/ionization-mass spectrometry (MALDI-MS) was used to analyze the...

  8. High-resolution line-scan analysis of resin-embedded sediments using laser ablation-inductively coupled plasma-mass spectrometry (LA-ICP-MS)

    NARCIS (Netherlands)

    Hennekam, R.; Jilbert, T.; de Lange, G.J.; Reichart, G.J.

    2015-01-01

    Laser ablation-inductively coupled plasma-mass spectrometry (LA-ICP-MS) line-scanning is a promising technique for producing high-resolution (µm-scale) geochemical records on resin-embedded sediments. However, this approach has not yet been thoroughly tested on sediment samples of known elemental

  9. Chemical characterization of neonicotinoids in surface waters by high performance liquid chromatography with Tandem Mass Spectrometry (HPLC MS/MS); Caracterização química dos neonicotinóides em águas superficiais via cromatografia liquída de alta eficiência acoplada a Espectrometria de Massas em Tandem (HPLC-MS/MS)

    Energy Technology Data Exchange (ETDEWEB)

    Amaral, Priscila Oliveira

    2017-07-01

    The present study aimed to develop a method for the determination and validation of a method for the identification and quantification of Neonicotinoids in surface waters collected in the Bauru region, in the state of São Paulo. The analytical techniques studied for the development of this method were the high performance liquid chromatography with tandem mass spectrometry (HPLC - MS / MS), gas chromatography with mass spectrometry (GC / MS) and gas chromatography with electron capture detector (GC / ECD). The class of pesticides Neonicotinoids was chosen for this work because it is related to a sudden disappearance of bees in colonies around the world. This phenomenon is known as Colony Collapse Disorder (CCD) and it is characterized by a rapid loss in the population of adult bees. The Neonicotinoids used in this study were the compounds Clothianidin, Imidacloprid and Thiamethoxam which were banned in their use as pesticides in Europe by Implementing Regulation No. 540/2011. The samples were concentrated using solid phase extraction (SPE) and liquid liquid extraction (LLE) techniques and injected into HPLC-MS / MS, GC / MS and GC / ECD. The GC / ECD and GC / MS techniques were not satisfactory for determination in the water matrix because the detection limit (10 mg L{sup -1}) is above the maximum allowed by the US Environmental Protection Agency (0.6 μg L{sup -1}). The HPLC - MS / MS technique using the multiple reaction monitoring (MRM) proved to be adequate for this study because it obtained quantification limits between 5.89 and 8.06 μg L{sup -1} and a linearity between 0.9963 and 0.9999 for the three compounds. (author)

  10. Solubility investigation of ether and ester essential oils in water using spectrometry and GC/MS

    Directory of Open Access Journals (Sweden)

    B. Khodabandeloo

    2017-11-01

    Full Text Available Background and objectives: Essential oils (volatiles are aromatic oily liquids prepared from different parts of plants and demonstrate various therapeutic and cosmetic properties. The dissolution of essential oils are not desirable in water, therefore the aim of this research was evaluation and selection the best co-solvents for increasing their solubility and bio availability. Methods:The solubility of six  plants essential oils were investigated in presence of propylene glycol (PG, polyethylene glycol 300 (PEG, glycerin and ethanol as solvent and tween 80 or lecithin as co-solvent by observation and spectrophotometric assay. Chemical composition of the essential oils and supersaturated 50% ethanol (SSE and 50% PG or PEG (SSP solutions were analyzed by GC/MS, too. Results: Ester (Lavandula dentata, Heracleum persicum and, Elettaria cardamomum essential oils showed the best solubility in ethanol and PG, respectively. Ether (Foeniculum vulgare, Pimpinella anisum and Petroselinum crispum essential oils had the best solubility in ethanol and PEG, respectively. In ester class, mixture of ethanol/water was the best solvent according to solubility and total amounts of major compounds of the essential oils. In ether class, all samples had better solubility in mixtures of ethanol/water than PEG, but the amounts of total phenols or ethers in SSP of some samples were higher than SSE. Therefore selecting the best solvent for these class need more experiments. Conclusion: Selecting the solvent for essential oils changes their chemical composition; therefore the best solvent was different for various purposes.

  11. Enzymatic tailoring of oleuropein from Olea europaea leaves and product identification by HRMS/MS spectrometry.

    Science.gov (United States)

    Nikolaivits, Efstratios; Termentzi, Aikaterini; Skaltsounis, Alexios-Leandros; Fokialakis, Nikolas; Topakas, Evangelos

    2017-07-10

    Oleuropein, a bioactive compound found in all parts of olive tree, especially in leaves and branches, presents numerous health promoting properties that increase research and market interest the last few years. In addition, oleuropein degradation products, such as hydroxytyrosol, elenolic acid, and the aglycones also exhibit biological activities with different properties compared to the starting compound. Under this view, a commercial lipase preparation Lipolase 100L and a thermophilic β-glucosidase from Myceliophthora thermophila were used for the regioselective hydrolysis of oleuropein towards the production of the corresponding biologically active compounds. The enzymatic degradation products of oleuropein, such as hydroxytyrosol, elenolic acid and its glucoside, and oleuropein aglycones were identified by LC-HRMS/MS and NMR spectroscopy. The latter, was found as a mix of diastereomers of the monoaldehydic form of oleuropein aglycone, identified as (5S, 8R, 9S)-, (5S, 8S, 9S)- and (5S, 8R, 9R). The high substrate specificity exhibited by both lipase and β-glucosidase allows the successful tailoring of oleuropein towards the production of different biologically active compounds with significant potential in the cosmeceutical and food industry. Copyright © 2017 Elsevier B.V. All rights reserved.

  12. Analytical and clinical performance of the new Fujirebio 25-OH vitamin D assay, a comparison with liquid chromatography-tandem mass spectrometry (LC-MS/MS) and three other automated assays.

    Science.gov (United States)

    Saleh, Lanja; Mueller, Daniel; von Eckardstein, Arnold

    2016-04-01

    We evaluated the analytical and clinical performance of the new Lumipulse® G 25-OH vitamin D assay from Fujirebio, and compared it to a liquid chromatography-tandem mass spectrometry (LC-MS/MS) method and three other commercial automated assays. Total 25 hydroxy vitamin D (25(OH)D) levels were measured in 100 selected serum samples from our routine analysis with Fujirebio 25(OH)D assay. The results were compared with those obtained with LC-MS/MS and three other automated 25(OH)D assays (Abbott, Beckman, and Roche). The accuracy of each assay tested was evaluated against a Labquality reference serum panel for 25(OH)D (Ref!25OHD; University of Ghent). Intra- and inter-day imprecision of the Fujirebio 25(OH)D assay was Lumipulse G 25-OH vitamin D assay from Fujirebio demonstrated a good correlation with LC-MS/MS and some immunoassays. The performance of the assay is well-suited for routine 25(OH)D measurement in clinical serum samples. A correction for the observed negative bias vs. LC-MS/MS could be considered.

  13. Biomarker discovery in low-grade breast cancer using isobaric stable isotope tags and two-dimensional liquid chromatography-tandem mass spectrometry (iTRAQ-2DLC-MS/MS) based quantitative proteomic analysis.

    Science.gov (United States)

    Bouchal, Pavel; Roumeliotis, Theodoros; Hrstka, Roman; Nenutil, Rudolf; Vojtesek, Borivoj; Garbis, Spiros D

    2009-01-01

    The present pilot study constitutes a proof-of-principle in the use of a quantitative LC-MS/MS based proteomic method for the comparative analysis of representative low-grade breast primary tumor tissues with and without metastases and metastasis in lymph node relative to the nonmetastatic tumor type. The study method incorporated iTRAQ stable isotope labeling, two-dimensional liquid chromatography, nanoelectrospray ionization and high resolution tandem mass spectrometry using the hybrid QqTOF platform (iTRAQ-2DLC-MS/MS). The principal aims of this study were (1) to define the protein spectrum obtainable using this approach, and (2) to highlight potential candidates for verification and validation studies focused on biomarkers involved in metastatic processes in breast cancer. The study resulted in the reproducible identification of 605 nonredundant proteins (p biomarker discovery program.

  14. A convenient method for calculation of ionic diffusion coefficients for accurate selected ion flow tube mass spectrometry, SIFT-MS

    Science.gov (United States)

    Dryahina, K.; Spanel, P.

    2005-07-01

    A method to calculate diffusion coefficients of ions important for the selected ion flow tube mass spectrometry, SIFT-MS, is presented. The ions, on which this method is demonstrated, include the SIFT-MS precursors H3O+(H2O)0,1,2,3, NO.+(H2O)0,1,2 and O2+ and the product ions relevant to analysis of breath trace metabolites ammonia (NH3+(H2O)0,1,2, NH4+(H2O)0,1,2), acetaldehyde (C2H4OH+(H2O)0,1,2), acetone (CH3CO+, (CH3)2CO+, (CH3)2COH+(H2O)0,1, (CH3)2CO.NO+), ethanol (C2H5OHH+(H2O)0,1,2) and isoprene (C5H7+, C5H8+, C5H9+). Theoretical model of the (12, 4) potential for interaction between the ions and the helium atoms is used, with the repulsive part approximated by the mean hard-sphere cross section and the attractive part describing ion-induced dipole interactions. The reduced zero-field mobilities at 300 K are calculated using the Viehland and Mason theory [L.A. Viehland, S.L. Lin, E.A. Mason, At. Data Nucl. Data Tables, 60 (1995) 37-95], parameterised by a simple formula as a function of the mean hard-sphere cross section, and converted to diffusion coefficients using the Einstein relation. The method is tested on a set of experimental data for simple ions and cluster ions.

  15. Ion-neutral potential models in atmospheric pressure ion mobility time-of-flight mass spectrometry IM(tof)MS.

    Science.gov (United States)

    Steiner, Wes E; English, William A; Hill, Herbert H

    2006-02-09

    The ion mobilities and their respective masses of several classes of amines (primary, secondary, and tertiary) were measured by electrospray ionization atmospheric pressure ion mobility time-of-flight mass spectrometry IM(tof)MS. The experimental data obtained were comparatively analyzed by the one-temperature kinetic theory of Chapman-Enskog. Several theoretical models were used to estimate the collision cross-sections; they include the rigid-sphere, polarization-limit, 12-6-4, and 12-4 potential models. These models were investigated to represent the interaction potentials contained within the collision integral that occurs between the polyatomic ions and the neutral drift gas molecules. The effectiveness of these collision cross-section models on predicting the mobility of these amine ions was explored. Moreover, the effects of drift gas selectivity on the reduced-mass term and in the collision cross-section term was examined. Use of a series of drift gases, namely, helium, neon, argon, nitrogen, and carbon dioxide, made it possible to distinguish between mass effects and polarizability effects. It was found that the modified 12-4 potential that compensates for the center of charge not being at the same location as the centers of mass showed improved agreement over the other collision cross-section models with respect to experimental data.

  16. Proton-transfer reaction mass spectrometry (PTR-MS) for the authentication of regionally unique South African lamb.

    Science.gov (United States)

    Erasmus, Sara W; Muller, Magdalena; Alewijn, Martin; Koot, Alex H; van Ruth, Saskia M; Hoffman, Louwrens C

    2017-10-15

    The volatile fingerprints of South African lamb meat and fat were measured by proton-transfer mass spectrometry (PTR-MS) to evaluate it as an authentication tool. Meat and fat of the Longissimus lumborum (LL) of lambs from six different regions were assessed. Analysis showed that the volatile fingerprints were affected by the origin of the meat. The classification of the origin of the lamb was achieved by examining the calculated and recorded fingerprints in combination with chemometrics. Four different partial least squares discriminant analysis (PLS-DA) models were fitted to the data to classify lamb meat and fat samples into "region of origin" (six different regions) and "origin" (Karoo vs. Non-Karoo). The estimation models classified samples 100% correctly. Validation of the first two models gave 42% (fat) and 58% (meat) correct classification of region, while the second two models performed better with 92% (fat) and 83% (meat) correct classification of origin. Copyright © 2017 Elsevier Ltd. All rights reserved.

  17. On the use of time-resolved laser-induced fluorescence (TRLIF) and electrospray mass spectrometry (ES-MS) for speciation studies

    International Nuclear Information System (INIS)

    Moulin, C.

    2003-01-01

    Time-resolved laser induced fluorescence (TRLIF) and electrospray mass spectrometry (ES-MS) are used for speciation studies. While the former has been used for long time, the latter is rather new in the field of speciation. These two techniques have different advantages such as sensitivity (especially for TRLIF), selectivity and multielement capabilities (in case of ES-MS). Examples obtained from studies carried out within the CEA are presented. Concerning TRLIF, emphasis is put on uranyl ion speciation in nitric acid to phosphoric acid going through hydroxo complexes. Concerning ES-MS, humic substances identification as well as speciation of cesium, zirconium, thorium and uranyl ions in various complexing media are presented. Comparisons of TRLIF and ES-MS results are made in the case of uranyl hydroxo complexes and favourably compared with OECD data. Trends for these two techniques are also discussed. (orig.)

  18. Profiling of nonvolatiles in whiskeys using ultra high pressure liquid chromatography quadrupole time-of-flight mass spectrometry (UHPLC-QTOF MS).

    Science.gov (United States)

    Collins, Thomas S; Zweigenbaum, Jerry; Ebeler, Susan E

    2014-11-15

    Commercial samples of 63 American whiskeys, including bourbon whiskeys, Tennessee whiskeys, rye whiskeys and other blended whiskeys were analysed using ultra high pressure liquid chromatography (UHPLC) coupled with quadrupole time-of-flight (QTOF) mass spectrometry (MS). The non-volatile composition of the whiskeys was used to model differences among the samples using discriminant analysis. The blended American whiskeys were readily distinguished from the remaining types. Additionally, most Tennessee whiskeys could be differentiated from bourbon and rye whiskeys. Similarly, younger (8 years old) whiskeys could be separated. The compounds important for differentiating among these whiskeys included wood derived phenolic compounds, lignan derived compounds and several C8 and larger lipids. A number of additional compounds differentiated the whiskeys but could not be identified using MS and MS/MS data alone. Copyright © 2014 Elsevier Ltd. All rights reserved.

  19. Simultaneous Detection of Androgen and Estrogen Abuse in Breeding Animals by Gas Chromatography-Mass Spectrometry/Combustion/Isotope Ratio Mass Spectrometry (GC-MS/C/IRMS) Evaluated against Alternative Methods.

    Science.gov (United States)

    Janssens, Geert; Mangelinckx, Sven; Courtheyn, Dirk; De Kimpe, Norbert; Matthijs, Bert; Le Bizec, Bruno

    2015-09-02

    The administration of synthetic homologues of naturally occurring steroids can be demonstrated by measuring (13)C/(12)C isotopic ratios of their urinary metabolites. Gas chromatography-mass spectrometry/combustion/isotope ratio mass spectrometry (GC-MS/C/IRMS) was used in this study to appraise in a global approach isotopic deviations of two 17β-testosterone metabolites (17α-testosterone and etiocholanolone) and one 17β-estradiol metabolite (17α-estradiol) together with those of 5-androstene-3β,17α-diol as endogenous reference compound (ERC). Intermediate precisions of 0.35‰, 1.05‰, 0.35‰, and 0.21‰, respectively, were observed (n = 8). To assess the performance of the analytical method, a bull and a heifer were treated with 17β-testosterone propionate and 17β-estradiol-3-benzoate. The sensitivity of the method permitted the demonstration of 17β-estradiol treatment up to 24 days. For 17β-testosterone treatment, the detection windows were 3 days and 24 days for the bull and the heifer, respectively. The capability of GC-MS/C/IRMS to demonstrate natural steroid abuse for urinary steroids was eventually compared to those of mass spectrometry (LC-MS/MS) when measuring intact steroid esters in blood and hair.

  20. [A comparative study of cadmium, lead, mercury, arsenic, selenium, manganese, copper and zinc in brown rice and fish by inductively coupled plasma-mass spectrometry (ICP-MS) and atomic absorption spectrometry].

    Science.gov (United States)

    Oshima, Harumi; Ueno, Eiji; Saito, Isao; Matsumoto, Hiroshi

    2004-10-01

    A study was conducted to evaluate the applicability of ICP-MS techniques for determination of metals in brown rice and fish. Cadmium, lead, mercury, arsenic, selenium, manganese, copper and zinc were determined by this method. An open digestion with nitric acid (Method A) and a rapid open digestion with nitric acid and hydrochloric acid (Method B) were used to solubilize analytes in samples, and these procedures were followed by ICP-MS analysis. Recovery of certified elements from standard reference materials by Method A and Method B ranged from 92 to 110% except for mercury (70 to 100%). Analytical results of brown rice and fish samples obtained by this ICP-MS agreed with those obtained by atomic absorption spectrometry (AAS). The results of this study demonstrate that quadrupole ICP-MS provides precise and accurate measurements of the elements tested in brown rice and fish samples.

  1. Single Laboratory Validated Method for Determination of Cylindrospermopsin and Anatoxin-a in Ambient Water by Liquid Chromatography/ Tandem Mass Spectrometry (LC/MS/MS)

    Science.gov (United States)

    This product is an LC/MS/MS single laboratory validated method for the determination of cylindrospermopsin and anatoxin-a in ambient waters. The product contains step-by-step instructions for sample preparation, analyses, preservation, sample holding time and QC protocols to ensu...

  2. Metabolites profiling of Pulsatilla saponin D in rat by ultra performance liquid chromatography-quadrupole time-of-flight mass spectrometry (UPLC/Q-TOF-MS/MS).

    Science.gov (United States)

    Ouyang, Hui; Zhou, Maofu; Guo, Yicheng; He, Mingzhen; Huang, Hesong; Ye, Xide; Feng, Yulin; Zhou, Xin; Yang, Shilin

    2014-07-01

    Pulsatilla saponin D, an antitumor substance isolated from traditional Chinese herbal medicine Pulsatilla chinensis (Bge.) Regel, is a promising candidate for new drug development. The purpose of the present study is to establish a simple and practical strategy for the metabolite profiling of Pulsatilla saponin D in vivo. A total of 18 metabolites were identified in rat plasma, urine and feces samples based on MS and MS/MS data by using ESI-Q-TOF-MS/MS, and eight of them (M11-M18) were reported for the first time. The results indicated that deglycosylation, dehydrogenation, hydroxylation and sulfation were the major metabolic transformations of Pulsatilla saponin D in vivo. This study has improved our understanding of the metabolic fate of Pulsatilla saponin D in vivo, and the information gained from the current study is relevant to the pharmacological activity of Pulsatilla saponin D. Copyright © 2014 Elsevier B.V. All rights reserved.

  3. Imaging of Selenium by Laser Ablation Inductively Coupled Plasma Mass Spectrometry (LA-ICP-MS) in 2-D Electrophoresis Gels and Biological Tissues.

    Science.gov (United States)

    Cruz, Elisa Castañeda Santa; Susanne Becker, J; Sabine Becker, J; Sussulini, Alessandra

    2018-01-01

    Selenium and selenoproteins are important components of living organisms that play a role in different biological processes. Laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS) is a powerful analytical technique that has been employed to obtain distribution maps of selenium in biological tissues in a direct manner, as well as in selenoproteins, previously separated by their molecular masses and isoelectric points using two-dimensional polyacrylamide gel electrophoresis (2-D PAGE). In this chapter, we present the protocols to perform LA-ICP-MS imaging experiments, allowing the distribution visualization and determination of selenium and/or selenoproteins in biological systems.

  4. Determination of the glycation sites of Bacillus anthracis neoglycoconjugate vaccine by MALDI-TOF/TOF-CID-MS/MS and LC-ESI-QqTOF-tandem mass spectrometry

    Science.gov (United States)

    Jahouh, Farid; Hou, Shu-jie; Kováč, Pavol; Banoub, Joseph H.

    2012-01-01

    We present herein an efficient mass spectrometric method for the localization of the glycation sites of a model neoglycoconjugate vaccine formed by a construct of the tetrasaccharide side chain of the Bacillus anthracis exosporium and the protein carrier bovine serum albumin. The glycoconjugate was digested with both trypsin and GluC V8 endoproteinases, and the digests were then analyzed by MALDI-TOF/TOF-CID-MS/MS and nano-LC-ESI-QqTOF-CID-MS/MS. The sequences of the unknown peptides analyzed by MALDI-TOF/TOF-CID-MS/MS, following digestion with the GluC V8 endoproteinase, allowed us to recognize three glycopeptides whose glycation occupancies were, respectively, on Lys 235, Lys 420, and Lys 498. Similarly, the same analysis was performed on the tryptic digests, which permitted us to recognize two glycation sites on Lys 100 and Lys 374. In addition, we have also used LC-ESI-QqTOF-CID-MS/MS analysis for the identification of the tryptic digests. However, this analysis identified a higher number of glycopeptides than would be expected from a glycoconjugate composed of a carbohydrate–protein ratio of 5.4:1, which would have resulted in glycation occupancies of 18 specific sites. This discrepancy was due to the large number of glycoforms formed during the synthetic carbohydrate–spacer–carrier protein conjugation. Likewise, the LC-ESI-QqTOF-MS/MS analysis of the GluC V8 digest also identified 17 different glycation sites on the synthetic glycoconjugate. PMID:22012665

  5. Contribution to the development of new analytical methods by the coupling between capillary electrophoresis and mass spectrometry (ICP-MS and ESI-MS): applications to the nuclear and biological fields

    International Nuclear Information System (INIS)

    Pitois, A.

    2006-04-01

    The coupling between chromatographic and electrophoretic separation techniques and mass spectrometry is used to combine the efficiency of the separation technique to the selectivity and sensitivity of the detectors. In this work, the number of applications of the CE-MS couplings has been increased. New analytical methods have been set up in the nuclear and biological fields. New analytical methods for the determination of fission products (cesium and lanthanides) have been developed by CE-ICP-MS. They enable to determine both concentration and isotopic composition of the fission products for very low detection limits (ng/mL by CE-Q-ICPMS, pg/mL by CE-HR-ICP-MS), since all the isobaric interferences are resolved. Moreover, only some nano-liters of sample are necessary to perform the analysis. These method have been applied with success to a simulated sample of spent fuel, to a nuclear sample from PUREX process and to a leaching of MOX fuel. Then, lanthanides have been analysed by CE-ESI-MS and the capability of ESI-MS to provide structural information has been studied. Elementary information has been obtained for strong potentials. Structural information has been obtained for low potentials. Finally, a new analytical method by CE-ESI-MS for the determination of 10B-boronophenylalanine (10B-BPA) has been developed for Boron Neutron Capture Therapy (BNCT). It has been applied to the cellular lines F98 and HUVEC. This CE-ESI-MS method has been validated by HR-ICP-MS. It enables a direct quantification of the chemical form 10B-BPA in samples of limited size (some nano-liters) and for low concentrations (ng/mL). As a consequence, this CE-ESI-MS method has enabled the study of the kinetics of 10B-BPA release and uptake for the F98 cells. (author)

  6. Matrix-assisted Laser Desorption Ionization-Time of Flight Mass Spectrometry (MALDI-TOF MS) Can Precisely Discriminate the Lineages of Listeria monocytogenes and Species of Listeria.

    Science.gov (United States)

    Ojima-Kato, Teruyo; Yamamoto, Naomi; Takahashi, Hajime; Tamura, Hiroto

    2016-01-01

    The genetic lineages of Listeria monocytogenes and other species of the genus Listeria are correlated with pathogenesis in humans. Although matrix-assisted laser desorption ionization-time of flight mass spectrometry (MALDI-TOF MS) has become a prevailing tool for rapid and reliable microbial identification, the precise discrimination of Listeria species and lineages remains a crucial issue in clinical settings and for food safety. In this study, we constructed an accurate and reliable MS database to discriminate the lineages of L. monocytogenes and the species of Listeria (L. monocytogenes, L. innocua, L. welshimeri, L. seeligeri, L. ivanovii, L. grayi, and L. rocourtiae) based on the S10-spc-alpha operon gene encoded ribosomal protein mass spectrum (S10-GERMS) proteotyping method, which relies on both genetic information (genomics) and observed MS peaks in MALDI-TOF MS (proteomics). The specific set of eight biomarkers (ribosomal proteins L24, L6, L18, L15, S11, S9, L31 type B, and S16) yielded characteristic MS patterns for the lineages of L. monocytogenes and the different species of Listeria, and led to the construction of a MS database that was successful in discriminating between these organisms in MALDI-TOF MS fingerprinting analysis followed by advanced proteotyping software Strain Solution analysis. We also confirmed the constructed database on the proteotyping software Strain Solution by using 23 Listeria strains collected from natural sources.

  7. Application of gas chromatography-mass spectrometry/combustion/isotope ratio mass spectrometry (GC-MS/C/IRMS) to detect the abuse of 17β-estradiol in cattle.

    Science.gov (United States)

    Janssens, Geert; Mangelinckx, Sven; Courtheyn, Dirk; Prévost, Stéphanie; De Poorter, Geert; De Kimpe, Norbert; Le Bizec, Bruno

    2013-07-31

    Although the ability to differentiate between endogenous steroids and synthetic homologues on the basis of their (13)C/(12)C isotopic ratio has been known for over a decade, this technique has been scarcely implemented for food safety purposes. In this study, a method was developed using gas chromatography-mass spectrometry/combustion/isotope ratio mass spectrometry (GC-MS/C/IRMS) to demonstrate the abuse of 17β-estradiol in cattle, by comparison of the (13)C/(12)C ratios of the main metabolite 17α-estradiol and an endogenous reference compound (ERC), 5-androstene-3β,17α-diol, in bovine urine. The intermediate precisions were determined as 0.46 and 0.26‰ for 5-androstene-3β,17α-diol and 17α-estradiol, respectively. This is, to the authors' knowledge, the first reported use of GC-MS/C/IRMS for the analysis of steroid compounds for food safety issues.

  8. The Effect of Collimating Lens Focusing on Laser Beam Shape in Matrix Assisted Laser Desorption/Ionization Mass Spectrometry (MALDI-MS).

    Science.gov (United States)

    O'Rourke, Matthew B; Raymond, Benjamin B A; Djordjevic, Steven P; Padula, Matthew P

    2018-03-01

    Tissue imaging using matrix assisted laser desorption/ionization mass spectrometry (MALDI-MS) is a well-established technique that, in recent years, has seen wider adoption and novel application. Applications such imaging mass spectrometry (IMS) and biotyping are beginning to gain greater exposure and use; however, with limitations in optimization methods, producing the best result often relies on the ability to customize the physical characteristics of the instrumentation, a task that is challenging for most mass spectrometry laboratories. With this in mind, we have described the effect of making simple adjustments to the laser optics at the final collimating lens area, to adjust the laser beam size and shape in order to allow greater customization of the instrument for improving techniques such as IMS. We have therefore been able to demonstrate that improvements can be made without requiring the help of an electrical engineer or external funding in a way that only costs a small amount of time. Graphical Abstract ᅟ.

  9. Contribution to the development of new analytical methods by the coupling between capillary electrophoresis and mass spectrometry (ICP-MS and ESI-MS): applications to the nuclear and biological fields; Contribution au developpement de nouvelles methodes analytiques par le couplage entre l'electrophorese capillaire et la spectrometrie de masse (ICP-MS et ESI-MS): applications dans les domaines nucleaires et biologiques

    Energy Technology Data Exchange (ETDEWEB)

    Pitois, A

    2006-04-15

    The coupling between chromatographic and electrophoretic separation techniques and mass spectrometry is used to combine the efficiency of the separation technique to the selectivity and sensitivity of the detectors. In this work, the number of applications of the CE-MS couplings has been increased. New analytical methods have been set up in the nuclear and biological fields. New analytical methods for the determination of fission products (cesium and lanthanides) have been developed by CE-ICP-MS. They enable to determine both concentration and isotopic composition of the fission products for very low detection limits (ng/mL by CE-Q-ICPMS, pg/mL by CE-HR-ICP-MS), since all the isobaric interferences are resolved. Moreover, only some nano-liters of sample are necessary to perform the analysis. These method have been applied with success to a simulated sample of spent fuel, to a nuclear sample from PUREX process and to a leaching of MOX fuel. Then, lanthanides have been analysed by CE-ESI-MS and the capability of ESI-MS to provide structural information has been studied. Elementary information has been obtained for strong potentials. Structural information has been obtained for low potentials. Finally, a new analytical method by CE-ESI-MS for the determination of 10B-boronophenylalanine (10B-BPA) has been developed for Boron Neutron Capture Therapy (BNCT). It has been applied to the cellular lines F98 and HUVEC. This CE-ESI-MS method has been validated by HR-ICP-MS. It enables a direct quantification of the chemical form 10B-BPA in samples of limited size (some nano-liters) and for low concentrations (ng/mL). As a consequence, this CE-ESI-MS method has enabled the study of the kinetics of 10B-BPA release and uptake for the F98 cells. (author)

  10. Quantification of the Triazole Antifungal Compounds Voriconazole and Posaconazole in Human Serum or Plasma Using Liquid Chromatography Electrospray Tandem Mass Spectrometry (HPLC-ESI-MS/MS).

    Science.gov (United States)

    Molinelli, Alejandro R; Rose, Charles H

    2016-01-01

    Voriconazole and posaconazole are triazole antifungal compounds used in the treatment of fungal infections. Therapeutic drug monitoring of both compounds is recommended in order to guide drug dosing to achieve optimal blood concentrations. In this chapter we describe an HPLC-ESI-MS/MS method for the quantification of both compounds in human plasma or serum following a simple specimen preparation procedure. Specimen preparation consists of protein precipitation using methanol and acetonitrile followed by a cleanup step that involves filtration through a cellulose acetate membrane. The specimen is then injected into an HPLC-ESI-MS/MS equipped with a C18 column and separated over an acetonitrile gradient. Quantification of the drugs in the specimen is achieved by comparing the response of the unknown specimen to that of the calibrators in the standard curve using multiple reaction monitoring.

  11. A simple validated multi-analyte method for detecting drugs in oral fluid by ultra-performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS).

    Science.gov (United States)

    Zheng, Yufang; Sparve, Erik; Bergström, Mats

    2018-06-01

    A UPLC-MS/MS method was developed to identify and quantitate 37 commonly abused drugs in oral fluid. Drugs of interest included amphetamines, benzodiazepines, cocaine, opiates, opioids, phencyclidine and tetrahydrocannabinol. Sample preparation and extraction are simple, and analysis times short. Validation showed satisfactory performance at relevant concentrations. The possibility of contaminated samples as well as the interpretation in relation to well-knows matrices, such as urine, will demand further study. Copyright © 2017 John Wiley & Sons, Ltd.

  12. Analysis of multiple vitamin D metabolites by ultra-performance supercritical fluid chromatography-tandem mass spectrometry (UPSFC-MS/MS).

    Science.gov (United States)

    Jenkinson, Carl; Taylor, Angela; Storbeck, Karl-Heinz; Hewison, Martin

    2018-06-15

    In recent years, increased interest in the human health benefits of vitamin D has led to demand for improved analysis of patient vitamin D 'status'. Studies to date have focused primarily on a single vitamin D metabolite, 25-hydroxyvitamin D, despite the existence of a broad range of vitamin D metabolites, referred to as the vitamin D metabolome. This study reports on the development of a rapid UPSFC-MS/MS method for the analysis of nine vitamin D metabolites in human serum. Optimum separation was obtained with a Lux-Cellulose chiral column. We observed an orthogonal elution order when compared with ultra-high performance liquid chromatography (UHPLC). The order of elution was reversed based on hydroxyl- group number, however elution order did not differ between isomeric changes in hydroxyl- group position or epimers. Although UPSFC yielded superior resolution and selectivity over previously developed UHPLC-MS/MS methods, improvements in sensitivity could not be achieved owing to the lower injection volume required for UPSFC relative to UHPLC. Method validation was performed on the developed UPSFC-MS/MS method and found to be within acceptable limits. Applying the method to the analysis of human serum samples showed a significant correlation with serum concentrations of metabolites measured by UHPLC-MS/MS (25OHD3 r = 0.997, P=<0.001, and 3-epi-25OHD3 r = 0.996, P ≤0.001). These data indicate that UPSFC provides an efficient analytical platform for rapid analysis of multiple vitamin D metabolites from serum. Crown Copyright © 2018. Published by Elsevier B.V. All rights reserved.

  13. Simultaneous analysis by Quadrupole-Orbitrap mass spectrometry and UHPLC-MS/MS for the determination of sedative-hypnotics and sleep inducers in adulterated products.

    Science.gov (United States)

    Lee, Ji Hyun; Park, Han Na; Choi, Ji Yeon; Kim, Nam Sook; Park, Hyung-Joon; Park, Seong Soo; Baek, Sun Young

    2017-12-01

    Adulterated products are continuously detected in society and cause problems. In this study, we developed and validated a method for determining synthetic sedative-hypnotics and sleep inducers, including barbital, benzodiazepam, zolpidem, and first-generation antihistamines, in adulterated products using Quadrupole-Orbitrap mass spectrometry and ultrahigh performance liquid chromatography with tandem mass spectrometry. In Quadrupole-Orbitrap mass spectrometry analysis, target compounds were confirmed using a combination of retention time, mass tolerance, mass accuracy, and fragment ions. For quantification, several validation parameters were employed using ultrahigh performance liquid chromatography with tandem mass spectrometry. The limit of detection and limit of quantitation was 0.05-53 and 0.17-177 ng/mL, respectively. The correlation coefficient for linearity was more than 0.995. The intra- and interassay accuracies were 86-110 and 84-111%, respectively. Their precision values were evaluated as within 4.0 (intraday) and 10.7% (interday). Mean recoveries of target compounds in adulterated products ranged from 85 to 116%. The relative standard deviation of stability was less than 10.7% at 4°C for 48 h. The 144 adulterated products obtained over 3 years (2014-2016) from online and in-person vendors were tested using established methods. After rapidly screening with Quadrupole-Orbitrap mass spectrometry, the detected samples were quantified using ultrahigh performance liquid chromatography with tandem mass spectrometry. Two of them were adulterated with phenobarbital. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  14. Developments in and applications of capillary electrophoresis inductively coupled plasma mass spectrometry

    International Nuclear Information System (INIS)

    Taylor, K.A.

    1999-08-01

    mass of enzyme and extraction temperature on the extraction efficiency was investigated. The chemical form of selenium present in the samples varied; inorganic selenate was identified as the chemical form of selenium in two of the samples, and for one sample selenomethionine was the predominant form of selenium. For one selenium enriched yeast sample, a matrix effect hindered the speciation. Selenium speciation in the selenium enriched yeasts and nutritional supplements was also undertaken using anion exchange HPLC-ICP-MS to allow a comparison of the two speciation techniques. (author)

  15. Chemical characterisation of non-defective and defective green arabica and robusta coffees by electrospray ionization-mass spectrometry (ESI-MS).

    Science.gov (United States)

    Mendonça, Juliana C F; Franca, Adriana S; Oliveira, Leandro S; Nunes, Marcella

    2008-11-15

    The coffee roasted in Brazil is considered to be of low quality, due to the presence of defective coffee beans that depreciate the beverage quality. These beans, although being separated from the non-defective ones prior to roasting, are still commercialized in the coffee trading market. Thus, it was the aim of this work to verify the feasibility of employing ESI-MS to identify chemical characteristics that will allow the discrimination of Arabica and Robusta species and also of defective and non-defective coffees. Aqueous extracts of green (raw) defective and non-defective coffee beans were analyzed by direct infusion electrospray ionization mass spectrometry (ESI-MS) and this technique provided characteristic fingerprinting mass spectra that not only allowed for discrimination of species but also between defective and non-defective coffee beans. ESI-MS profiles in the positive mode (ESI(+)-MS) provided separation between defective and non-defective coffees within a given species, whereas ESI-MS profiles in the negative mode (ESI(-)-MS) provided separation between Arabica and Robusta coffees. Copyright © 2008 Elsevier Ltd. All rights reserved.

  16. Identification of Enterobacteriaceae by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry using the VITEK MS system.

    Science.gov (United States)

    Richter, S S; Sercia, L; Branda, J A; Burnham, C-A D; Bythrow, M; Ferraro, M J; Garner, O B; Ginocchio, C C; Jennemann, R; Lewinski, M A; Manji, R; Mochon, A B; Rychert, J A; Westblade, L F; Procop, G W

    2013-12-01

    This multicenter study evaluated the accuracy of matrix-assisted laser desorption/ionization time-of-flight (MALDI-TOF) mass spectrometry identifications from the VITEK MS system (bioMérieux, Marcy l'Etoile, France) for Enterobacteriaceae typically encountered in the clinical laboratory. Enterobacteriaceae isolates (n = 965) representing 17 genera and 40 species were analyzed on the VITEK MS system (database v2.0), in accordance with the manufacturer's instructions. Colony growth (≤72 h) was applied directly to the target slide. Matrix solution (α-cyano-4-hydroxycinnamic acid) was added and allowed to dry before mass spectrometry analysis. On the basis of the confidence level, the VITEK MS system provided a species, genus only, or no identification for each isolate. The accuracy of the mass spectrometric identification was compared to 16S rRNA gene sequencing performed at MIDI Labs (Newark, DE). Supplemental phenotypic testing was performed at bioMérieux when necessary. The VITEK MS result agreed with the reference method identification for 96.7% of the 965 isolates tested, with 83.8% correct to the species level and 12.8% limited to a genus-level identification. There was no identification for 1.7% of the isolates. The VITEK MS system misidentified 7 isolates (0.7 %) as different genera. Three Pantoea agglomerans isolates were misidentified as Enterobacter spp. and single isolates of Enterobacter cancerogenus, Escherichia hermannii, Hafnia alvei, and Raoultella ornithinolytica were misidentified as Klebsiella oxytoca, Citrobacter koseri, Obesumbacterium proteus, and Enterobacter aerogenes, respectively. Eight isolates (0.8 %) were misidentified as a different species in the correct genus. The VITEK MS system provides reliable mass spectrometric identifications for Enterobacteriaceae.

  17. Improved sensitivity of ochratoxin A analysis in coffee using high-performance liquid chromatography with hybrid triple quadrupole-linear ion trap mass spectrometry (LC-QqQLIT-MS/MS).

    Science.gov (United States)

    Kokina, Aija; Pugajeva, Iveta; Bartkevics, Vadims

    2016-01-01

    A novel and sensitive method utilising high-performance liquid chromatography coupled to triple quadrupole-linear ion trap mass spectrometry (LC-QqQLIT-MS/MS) was developed in order to analyse the content of ochratoxin A (OTA) in coffee samples. The introduction of the triple-stage MS scanning mode (MS(3)) has been shown to increase greatly sensitivity and selectivity by eliminating the high chromatographic baseline caused by interference of complex coffee matrices. The analysis included the sample preparation procedure involving extraction of OTA using a methanol-water mixture and clean-up by immunoaffinity columns and detection using the MS(3) scanning mode of LC-QqQLIT-MS/MS. The proposed method offered a good linear correlation (r(2) > 0.998), excellent precision (RSD coffee beans and espresso beverages was 0.010 and 0.003 µg kg(-1), respectively. The developed procedure was compared with traditional methods employing liquid chromatography coupled to fluorescent and tandem quadrupole detectors in conjunction with QuEChERS and solid-phase extraction. The proposed method was successfully applied to the determination of OTA in 15 samples of coffee beans and in 15 samples of espresso coffee beverages obtained from the Latvian market. OTA was found in 10 samples of coffee beans and in two samples of espresso in the ranges of 0.018-1.80 µg kg(-1) and 0.020-0.440 µg l(-1), respectively. No samples exceeded the maximum permitted level of OTA in the European Union (5.0 µg kg(-1)).

  18. Determination of levodopa in human plasma by high performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS: application to a bioequivalence study

    Directory of Open Access Journals (Sweden)

    Heliana F. Martins

    2013-01-01

    Full Text Available A sensitive, accurate and simple method using HPLC-MS/MS was developed and validated for levodopa quantitation in human plasma. Analysis was achieved on a pursuit® C18 analytical column (5 µm; 150 x 4.6 mm i.d. using a mobile phase (methanol and water , 90:10, v/v containing formic acid 0.5% v/v, after extracting the samples using a simple protein plasma precipitation with perchloric acid. The developed method was validated in accordance with ANVISA guidelines and was successfully applied to a bioequivalence study in 60 healthy volunteers demonstrating the feasibility and reliability of the proposed method.

  19. Real Time Extraction Kinetics of Electro Membrane Extraction Verified by Comparing Drug Metabolism Profiles Obtained from a Flow-Flow Electro Membrane Extraction-Mass Spectrometry System with LC-MS

    DEFF Research Database (Denmark)

    Fuchs, David; Jensen, Henrik; Pedersen-Bjergaard, Stig

    2015-01-01

    A simple to construct and operate, "dip-in" electromembrane extraction (EME) probe directly coupled to electrospray ionization-mass spectrometry (ESI-MS) for rapid extraction and real time analysis of various analytes was developed. The setup demonstrated that EME-MS can be used as a viable...... alternative to conventional protein precipitation followed by liquid chromatography-mass spectrometry (LC-MS) for studying drug metabolism. Comparison of EME-MS with LC-MS for drug metabolism analysis demonstrated for the first time that real time extraction of analytes by EME is possible. Metabolism kinetics...... offering a significant time saving as compared to conventional LC-MS where laborious protein precipitation or other sample pretreatments are required before analysis. This makes the developed EME-MS setup a highly promising sample preparation method for various kinds of applications where fast and real-time...

  20. Feasibility of matrix-assisted laser desorption/ionisation time-of-flight mass spectrometry (MALDI-TOF MS) networking in university hospitals in Brussels.

    Science.gov (United States)

    Martiny, D; Cremagnani, P; Gaillard, A; Miendje Deyi, V Y; Mascart, G; Ebraert, A; Attalibi, S; Dediste, A; Vandenberg, O

    2014-05-01

    The mutualisation of analytical platforms might be used to address rising healthcare costs. Our study aimed to evaluate the feasibility of networking a unique matrix-assisted laser desorption/ionisation time-of-flight mass spectrometry (MALDI-TOF MS) system for common use in several university hospitals in Brussels, Belgium. During a one-month period, 1,055 successive bacterial isolates from the Brugmann University Hospital were identified on-site using conventional techniques; these same isolates were also identified using a MALDI-TOF MS system at the Porte de Hal Laboratory by sending target plates and identification projects via transportation and the INFECTIO_MALDI software (Infopartner, Nancy, France), respectively. The occurrence of transmission problems (MS networking always provided a faster identification result than conventional techniques, except when chromogenic culture media and oxidase tests were used (p MS networking could lead to substantial annual cost savings. MALDI-TOF MS networking presents many advantages, and few conventional techniques (optochin and oxidase tests) are required to ensure the same quality in patient care from the distant laboratory. Nevertheless, such networking should not be considered unless there is a reorganisation of workflow, efficient communication between teams, qualified technologists and a reliable IT department and helpdesk to manage potential connectivity problems.

  1. Introducing AAA-MS, a rapid and sensitive method for amino acid analysis using isotope dilution and high-resolution mass spectrometry.

    Science.gov (United States)

    Louwagie, Mathilde; Kieffer-Jaquinod, Sylvie; Dupierris, Véronique; Couté, Yohann; Bruley, Christophe; Garin, Jérôme; Dupuis, Alain; Jaquinod, Michel; Brun, Virginie

    2012-07-06

    Accurate quantification of pure peptides and proteins is essential for biotechnology, clinical chemistry, proteomics, and systems biology. The reference method to quantify peptides and proteins is amino acid analysis (AAA). This consists of an acidic hydrolysis followed by chromatographic separation and spectrophotometric detection of amino acids. Although widely used, this method displays some limitations, in particular the need for large amounts of starting material. Driven by the need to quantify isotope-dilution standards used for absolute quantitative proteomics, particularly stable isotope-labeled (SIL) peptides and PSAQ proteins, we developed a new AAA assay (AAA-MS). This method requires neither derivatization nor chromatographic separation of amino acids. It is based on rapid microwave-assisted acidic hydrolysis followed by high-resolution mass spectrometry analysis of amino acids. Quantification is performed by comparing MS signals from labeled amino acids (SIL peptide- and PSAQ-derived) with those of unlabeled amino acids originating from co-hydrolyzed NIST standard reference materials. For both SIL peptides and PSAQ standards, AAA-MS quantification results were consistent with classical AAA measurements. Compared to AAA assay, AAA-MS was much faster and was 100-fold more sensitive for peptide and protein quantification. Finally, thanks to the development of a labeled protein standard, we also extended AAA-MS analysis to the quantification of unlabeled proteins.

  2. Quantification of trace amounts of rare earth elements in high purity gadolinium oxide by sector field inductively coupled plasma mass spectrometry (ICP-MS)

    International Nuclear Information System (INIS)

    Pedreira, W.R.; Silva Queiroz, C.A. da; Abrao, A.; Pimentel, M.M.

    2004-01-01

    In recent years, rare earth elements (REEs) have received much attention in the fields of geochemistry and industry. Gadolinium oxide is used for many different high technology applications such as infrared absorbing automotive glass, petroleum cracking catalyst, gadolinium-yttrium garnets, microwave applications, and color TV tube phosphors. It can also be used in optical glass manufacturing and in the electronic industry. Rapid and accurate determinations of the rare earth elements are increasingly required as industrial demands expand. In general, the inductively coupled plasma mass spectrometry (ICP-MS) presents some advantages for trace element analysis, due to high sensitivity and resolution, when compared with other analytical techniques. In this work, sector field inductively coupled plasma mass spectrometry was used. Sixteen elements (Sc, Y, and 14 lanthanides) were determined selectively with the ICP-MS system using a concentration gradient method. The detection limits with the ICP-MS system were about 0.2-8 pg ml -1 . The recovery percentage ranged from 95 to 100% for different rare earth elements. The %R.S.D. of the methods varying between 1.5 and 2.5% for a set of five (n=5) replicates was found for the IPEN's material and for the certificate reference sample. Determination of trace REEs in two high pure gadolinium oxides samples (IPEN and JMC) was performed. IPEN's material is highly pure (>99.99%) and was successfully analyzed without spectral interference

  3. Evaluation of laser diode thermal desorption (LDTD) coupled with tandem mass spectrometry (MS/MS) for support of in vitro drug discovery assays: increasing scope, robustness and throughput of the LDTD technique for use with chemically diverse compound libraries.

    Science.gov (United States)

    Beattie, Iain; Smith, Aaron; Weston, Daniel J; White, Peter; Szwandt, Simon; Sealey, Laura

    2012-02-05

    Within the drug discovery environment, the key process in optimising the chemistry of a structural series toward a potential drug candidate is the design, make and test cycle, in which the primary screens consist of a number of in vitro assays, including metabolic stability, cytochrome P450 inhibition, and time-dependent inhibition assays. These assays are often carried out using multiple drug compounds with chemically diverse structural features, often in a 96 well-plate format for maximum time-efficiency, and are supported using rapid liquid chromatographic (LC) sample introduction with a tandem mass spectrometry (MS/MS) selected reaction monitoring (SRM) endpoint, taking around 6.5 h per plate. To provide a faster time-to-decision at this critical point, there exists a requirement for higher sample throughput and a robust, well-characterized analytical alternative. This paper presents a detailed evaluation of laser diode thermal desorption (LDTD), a relatively new ambient sample ionization technique, for compound screening assays. By systematic modification of typical LDTD instrumentation and workflow, and providing deeper understanding around overcoming a number of key issues, this work establishes LDTD as a practical, rapid alternative to conventional LC-MS/MS in drug discovery, without need for extensive sample preparation or expensive, scope-limiting internal standards. Analysis of both the five and three cytochrome P450 competitive inhibition assay samples by LDTD gave improved sample throughput (0.75 h per plate) and provided comparable data quality as the IC₅₀ values obtained were within 3 fold of those calculated from the LC-MS/MS data. Additionally when applied generically to a chemically diverse library of over 250 proprietary compounds from the AstraZeneca design, make and test cycle, LDTD demonstrated a success rate of 98%. Copyright © 2011 Elsevier B.V. All rights reserved.

  4. Accuracy of the Precision® point-of-care ketone test examined by liquid chromatography tandem-mass spectrometry (LC-MS/MS) in the same fingerstick sample.

    Science.gov (United States)

    Janssen, Marcel J W; Hendrickx, Ben H E; Habets-van der Poel, Carin D; van den Bergh, Joop P W; Haagen, Anton A M; Bakker, Jaap A

    2010-12-01

    The Precision(®) (Abbott Diabetes Care) point-of-care biosensor test strips are widely used by patients with diabetes and clinical laboratories for measurement of plasma β-hydroxybutyrate (β-HB) concentrations in capillary blood samples obtained by fingerstick. In the literature, this procedure has been validated only against the enzymatic determination of β-HB in venous plasma, i.e., the method to which the Precision(®) has been calibrated. In this study, the Precision(®) Xceed was compared to a methodologically different and superior procedure: determination of β-HB by liquid chromatography tandem-mass spectrometry (LC-MS/MS) in capillary blood spots. Blood spots were obtained from the same fingerstick sample from out of which Precision(®) measurements were performed. Linearity was tested by adding varying amounts of standard to an EDTA venous whole blood matrix. The Precision(®) was in good agreement with LC-MS/MS within the measuring range of 0.0-6.0 mmol/L (Passing and Bablok regression: slope=1.20 and no significant intercept, R=0.97, n=59). Surprisingly, the Precision(®) showed non-linearity and full saturation at concentrations above 6.0 mmol/L, which were confirmed by a standard addition experiment. Results obtained at the saturation level varied between 3.0 and 6.5 mmol/L. The Precision(®) β-HB test strips demonstrate good comparison with LC-MS/MS. Inter-individual variation around the saturation level, however, is large. Therefore, we advise reporting readings above 3.0 as >3.0 mmol/L. The test is valid for use in the clinically relevant range of 0.0-3.0 mmol/L.

  5. Parabens in urine, serum and seminal plasma from healthy Danish men determined by liquid chromatography-tandem mass spectrometry (LC-MS/MS)

    DEFF Research Database (Denmark)

    Frederiksen, Hanne; Jørgensen, Niels; Andersson, Anna-Maria

    2011-01-01

    Parabens are used as anti-microbial preservatives in a range of consumer products, especially in cosmetics. In vitro and animal studies have shown weak estrogenic and other endocrine disrupting effects of parabens, including reduced testosterone levels in exposed male rats. The knowledge of paraben...... exposure, distribution and excretion in humans is limited. In this study we determined the concentration of five parabens; methyl-, ethyl-, n-propyl-, n-butyl- and benzylparaben in urine, serum and seminal plasma samples from 60 healthy Danish men. To conduct the study a sensitive and specific method using...... LC-MS/MS for simultaneous determination of the five parabens was developed for all three different matrices. Highest concentrations of the parabens were found in urine, wherein methyl-, ethyl-, n-propyl- and n-butyl parabens were measurable in 98%, 80%, 98% and 83% of the men, respectively. Benzyl...

  6. Development of a chromatographic separation method hyphenated to electro-spray ionization mass spectrometry (ESI-MS) and inductively coupled plasma mass spectrometry (ICP-MS): application to the lanthanides speciation analysis

    International Nuclear Information System (INIS)

    Beuvier, Ludovic

    2015-01-01

    This work focuses on the development of a chromatographic separation method coupled to both ESI-MS and ICP-MS in order to achieve the comprehensive speciation analysis of lanthanides in aqueous phase representative of back-extraction phases of advanced spent nuclear fuel treatment processes. This analytical method allowed the separation, the characterization and the quantitation of lanthanides complexes holding poly-aminocarboxylic ligands, such as DTPA and EDTA, used as complexing agents in these processes. A HILIC separation method of lanthanides complexes has been developed with an amide bonded stationary phase. A screening of a wide range of mobile phase compositions demonstrated that the adsorption mechanism was predominant. This screening allowed also obtaining optimized separation conditions. Faster analysis conditions with shorter amide column packed with sub 2 μm particles reduced analysis time by 2.5 and 25% solvent consumption. Isotopic and structural characterization by HILIC ESI-MS was performed as well as the development of external calibration quantitation method. Analytical performances of quantitation method were determined. Finally, the development of the HILIC coupling to ESI-MS and ICP-MS was achieved. A simultaneous quantitation method by ESI-MS and ICP-MS was performed to determine the species quantitative distribution in solution. Analytical performances of quantitation method were also determined. (author) [fr

  7. Ways for accurate analysis of high purity materials using the glow discharge mass spectrometry (GD-MS); Wege zur genauen Charakterisierung hochreiner Materialien mit der Glimmentladungs-Massenspektrometrie (GD-MS)

    Energy Technology Data Exchange (ETDEWEB)

    Gusarova, Tamara

    2010-04-14

    The main aim of this work consists in the investigation, development and application of improved possibilities of accurate analysis of high purity materials using the solid sample technique of Glow Discharge Mass Spectrometry (GD-MS), as well as in the sensitivity enhancement of GD Optical Emission Spectrometry (GD-OES) by implicating the hollow cathode effect. The emphasis of the PhD thesis consists in the accurate quantification for GD-MS. As appropriate certified reference materials (CRMs) for calibration are lacking in most cases an accurate quantification especially for trace elements mass fractions at {mu}g kg{sup -1} level can often not be achieved. To overcome this problem and to expand the possibilities of modern GD-MS hereby, synthetic standards were applied for calibration of both high resolution GD-MS instruments ''VG 9000'' and ''Element GD''. The standards were prepared by doping of matrix powder with trace element standard solutions followed by drying and pressing the doped powder to compact pellets. With the quantification approach worked out and described here accurate analysis results with small uncertainties can be achieved for most elements of periodic table in almost every matrix composition. Furthermore direct traceability of the analytical results to the International System of Units (SI) is provided ensuring their higher metrological quality. Numerous additional systematic investigations concerning the preparation of the synthetic standards and their properties were carried out. The results of calibration of GD-MS instruments with synthetic standards for Co (Co-C), Cu, In, Fe and Zn matrices were checked by measuring CRMs. These results were also contrasted with those of other quantification approaches, as usually used in GD-MS routine. The results achieved with synthetic standards had the highest accuracy. The successful participation in the round robin test CCQM-P107 between international

  8. Micron Scale Mapping and Depth Profiling of Organic Compounds in Geologic Material: Femtosecond - Laser Desorption Laser Postionization - Mass Spectrometry (fs-LDPI-MS)

    Science.gov (United States)

    Pasterski, M. J.; Barry, G. E.; Hanley, L.; Kenig, F. P. H.

    2017-12-01

    One of the major challenges within the field of organic geochemistry is to determine whether an observed biomarker signature is indigenous (emplaced during sedimentation), non-indigenous (emplaced after sedimentation) or contaminant (incorporated during sampling, storage or analysis). The challenge of determining the mode of emplacement of an observed biomarker signature is accentuated in analyses of Precambrian samples, and may be an issue upon Mars sample return. Current geochemical techniques (e.g. gas chromatography-mass spectrometry, GC-MS, GC×GC-MS) can determine the composition and structure of the organic constituents of a sample. However, the preparatory steps necessary prior to GC-MS analysis (sample crushing, solvent extraction) make it impossible to determine the precise spatial distribution of organic molecules within rocks and sediments. Here, we will present data from the first set of micron (2-5 μm width × 8 μm depth) resolution MS-images of organic compounds in geologic material. Fs-LDPI-MS was utilized to create MS-images of organic compounds in four samples: (1) an Antarctic igneous dike used as a sample blank; (2) a 93 million year-old (Ma) burrowed carbonate collected near Pueblo, CO; (3) a 164 Ma organic rich mudstone collected in central England; and (4) a 2680 Ma metasediment collected in Timmins, ON, Canada. Prior to this study, all samples had been analyzed via GC-MS to determine the bulk hydrocarbon composition. For this study, thick sections (70-100 μm thick) were prepared in-house using custom-designed clean preparation techniques. Petrographic maps of the thick sections were created to highlight geologic features such as burrows (sample 2), particulate organic matter (sample 3) and hydrothermal veins (sample 4). Fs-LDPI-MS analysis was performed on the mapped thick sections. MS-images of targeted organic compounds were created, and the MS-images were overlain with the petrographic maps to determine the spatial distribution of the

  9. SOLID PHASE MICRO EXTRACTION (SPME) FLAVOR ANALYSIS OF APPLE JUICE AND COFFEE MIXTURES USING GAS CHROMATOGRAPHY-MASS SPECTROMETRY (GC-MS)

    OpenAIRE

    Mi Ja Kim; Jeehyun Lee; Jaeyoung Byun; Sunmi Choi; Wonsik Choi

    2016-01-01

    This research was conducted to evaluate the flavor of apple juice and coffee mixtures and the sensory quality of SPME extracts using gas chromatography-mass spectrometry (GC-MS). Three samples with different compositions were examined. Sample A1 contained85% apple juiceand 15% coffee, sample A2 had87.5% apple and 12.5% coffee, and sample A3 had90% apple juiceand 10% coffee. The sensory analysis involved 100 panelists and a sequential monadic test. Sample presentation orders were balanced in ...

  10. Identification of protein biomarkers in Dupuytren's contracture using surface enhanced laser desorption ionization time-of-flight mass spectrometry (SELDI-TOF-MS).

    Science.gov (United States)

    O'Gorman, David; Howard, Jeffrey C; Varallo, Vincenzo M; Cadieux, Peter; Bowley, Erin; McLean, Kris; Pak, Brian J; Gan, Bing Siang

    2006-06-01

    To study the protein expression profiles associated with Dupuytren's contracture (DC) to identify potential disease protein biomarkers (PBM) using a proteomic technology--Surface Enhanced Laser Desorption/Ionization Time-of-Flight Mass Spectrometry (SELDI-TOF-MS). Normal and disease palmar fascia from DC patients were analyzed using Ciphergen's SELDI-TOF-MS Protein Biological System II (PBSII) ProteinChip reader. Analysis of the resulting SELDI-TOF spectra was carried out using the peak cluster analysis program (BioMarker Wizard, Ciphergen). Common peak clusters were then filtered using a bootstrap algorithm called SAM (Significant Analysis of Microarrays) for increased fidelity in our analysis. Several differentially expressed low molecular weight (mass standard deviation for both methods of biomarker-rich low molecular weight region of the human proteome. Application of such novel technology may help clinicians to focus on specific molecular abnormalities in diseases with no known molecular pathogenesis, and uncover therapeutic and/or diagnostic targets.

  11. Determination of vandetanib in human plasma and cerebrospinal fluid by liquid chromatography electrospray ionization tandem mass spectrometry (LC-ESI-MS/MS).

    Science.gov (United States)

    Bai, Feng; Johnson, Jennifer; Wang, Fan; Yang, Lei; Broniscer, Alberto; Stewart, Clinton F

    2011-09-01

    A sensitive and precise LC-ESI-MS/MS method for the determination of vandetanib (ZD6474) in human plasma and cerebrospinal fluid (CSF) using [(13)C,d(3)]-ZD6474 as an internal standard (ISTD) was developed and validated. Sample preparation consisted of a simple liquid-liquid extraction with tert-butyl methyl ether containing 0.1% or 0.5% ammonium hydroxide. ZD6474 and ISTD were separated on a Kinetex C18 column (2.6 μm, 50 mm × 2.1 mm) at ambient temperature with an isocratic mobile phase (acetonitrile/10mM ammonium formate=50/50, v/v, at pH 5.0) delivered at 0.11 mL/min. The retention time of both compounds was at 1.60 min in a runtime of three min. Detection was achieved by an API-3200 LC-MS/MS system, monitoring m/z 475.1/112.1 and m/z 479.1/116.2 for vandetanib and ISTD, respectively. The method was linear in the range of 0.25-50 ng/mL (R(2) ≥ 0.990) for the CSF curve and from 1.0 to 3000 ng/mL (R(2) ≥ 0.992) for the plasma curve. The mean recovery for vandetanib was 80%. Within-day and between-day precisions were ≤ 8.8% and ≤ 5.9% for CSF and plasma, respectively. Within-day and between-day accuracies ranged from 95.0 to 98.5% for CSF, and from 104.0 to 108.5% for plasma. Analysis of plasma from six different sources showed no matrix effect for vandetanib (MF=0.98, %CV ≤ 4.97, n=6). This method was successfully applied to the analysis of pharmacokinetic samples from children with brain tumors treated with oral vandetanib. Copyright © 2011 Elsevier B.V. All rights reserved.

  12. Determination of crenolanib in human serum and cerebrospinal fluid by liquid chromatography-electrospray ionization-tandem mass spectrometry (LC-ESI-MS/MS).

    Science.gov (United States)

    Roberts, Michael S; Turner, David C; Owens, Thandranese S; Ramachandran, Abhijit; Wetmore, Cynthia; Throm, Stacy L; Stewart, Clinton F

    2013-06-15

    A LC-ESI-MS/MS method for the determination of crenolanib (CP-868,596) in human serum was developed and validated employing d4-CP-868,596 as an internal standard (ISTD). In addition to human serum, the method was also partially validated for crenolanib determination in human cerebrospinal fluid (CSF) samples. Sample aliquots (50μl of serum or CSF) were prepared for analysis using liquid-liquid extraction (LLE) with tert-butyl methyl ether. Chromatography was performed using a phenomenex Gemini C18 column (3μm, 100mm×4.6mm I.D.) in a column heater set at 50°C and an isocratic mobile phase (methanol/water/formic acid at a volume ratio of 25/25/0.15, v/v/v). The flow rate was 0.45mL/min, and the retention time for both analyte and ISTD was less than 3.5min. Samples were analyzed with an API-5500 LC-MS/MS system (ESI) in positive ionization mode coupled to a Shimadzu HPLC system. The ion transitions monitored were m/z 444.4→373.1 and m/z 448.2→374.2 for crenolanib and ISTD, respectively. The method was linear over the range of 5-1000ng/mL for serum and 0.5-1000ng/mL for CSF. For human serum, both intra-day and inter-day precision were <4%, while intra-day and inter-day accuracy were within 8% of nominal values. Recovery was greater than 50% for both the analyte and ISTD. For CSF samples, both intra-day and inter-day precision were <9% except at the lower limit of quantification (LLOQ) which was <17%. The intra-day and inter-day accuracy were within 11% of the nominal CSF concentrations. After validation, this method was successfully applied to the analysis of serial pharmacokinetic samples obtained from a child treated with oral crenolanib. Copyright © 2013 Elsevier B.V. All rights reserved.

  13. Multiwalled carbon nanotubes as a solid-phase extraction adsorbent for the determination of three barbiturates in pork by ion trap gas chromatography-tandem mass spectrometry (GC/MS/MS) following microwave assisted derivatization

    Energy Technology Data Exchange (ETDEWEB)

    Zhao Haixiang [College of Science, China Agricultural University, Beijing 100094 (China); Inspection Technology and Equipment Institute, Chinese Academy of Inspection and Quarantine, Beijing 100025 (China); Department of Basic Agricultural Science, Hebei North College, Zhangjiakou Hebei 075131 (China); Wang Liping [College of Science, China Agricultural University, Beijing 100094 (China); Qiu Yueming [Inspection Technology and Equipment Institute, Chinese Academy of Inspection and Quarantine, Beijing 100025 (China); Zhou Zhiqiang [College of Science, China Agricultural University, Beijing 100094 (China)]. E-mail: zqzhou@cau.edu.cn; Zhong Weike [Inspection Technology and Equipment Institute, Chinese Academy of Inspection and Quarantine, Beijing 100025 (China); Li Xiang [Inspection Technology and Equipment Institute, Chinese Academy of Inspection and Quarantine, Beijing 100025 (China)

    2007-03-14

    A new method was developed for the rapid screening and confirmation analysis of barbital, amobarbital and phenobarbital residues in pork by gas chromatography-tandem mass spectrometry (GC/MS/MS) with ion trap MSD. The residual barbiturates in pork were extracted by ultrasonic extraction, cleaned up on a multiwalled carbon nanotubes (MWCNTs) packed solid phase extraction (SPE) cartridge and applied acetone-ethyl acetate (3:7, v/v) mixture as eluting solvent and derivatized with CH{sub 3}I under microwave irradiation. The methylated barbiturates were separated on a TR-5MS capillary column and detected with an ion trap mass detector. Electron impact ion source (EI) operating MS/MS mode was adopted for identification and external standard method was employed for quantification. One precursor ion m/z 169 was selected for analysis of barbital and amobarbital and m/z 232 was selected for phenobarbital. The product ions were obtained under 1.0 V excitation voltage. Good linearities (linear coefficient R > 0.99) were obtained at the range of 0.5-50 {mu}g kg{sup -1}. Limit of detection (LOD) of barbital was 0.2 {mu}g kg{sup -1} and that of amobarbital and phenobarbital were both 0.1 {mu}g kg{sup -1} (S/N {>=} 3). Limit of quatification (LOQ) was 0.5 {mu}g kg{sup -1} for three barbiturates (S/N {>=} 10). Satisfying recoveries ranging from 75% to 96% of the three barbiturates spiked in pork were obtained, with relative standard deviations (R.S.D.) in the range of 2.1-7.8%.

  14. Multiwalled carbon nanotubes as a solid-phase extraction adsorbent for the determination of three barbiturates in pork by ion trap gas chromatography-tandem mass spectrometry (GC/MS/MS) following microwave assisted derivatization

    International Nuclear Information System (INIS)

    Zhao Haixiang; Wang Liping; Qiu Yueming; Zhou Zhiqiang; Zhong Weike; Li Xiang

    2007-01-01

    A new method was developed for the rapid screening and confirmation analysis of barbital, amobarbital and phenobarbital residues in pork by gas chromatography-tandem mass spectrometry (GC/MS/MS) with ion trap MSD. The residual barbiturates in pork were extracted by ultrasonic extraction, cleaned up on a multiwalled carbon nanotubes (MWCNTs) packed solid phase extraction (SPE) cartridge and applied acetone-ethyl acetate (3:7, v/v) mixture as eluting solvent and derivatized with CH 3 I under microwave irradiation. The methylated barbiturates were separated on a TR-5MS capillary column and detected with an ion trap mass detector. Electron impact ion source (EI) operating MS/MS mode was adopted for identification and external standard method was employed for quantification. One precursor ion m/z 169 was selected for analysis of barbital and amobarbital and m/z 232 was selected for phenobarbital. The product ions were obtained under 1.0 V excitation voltage. Good linearities (linear coefficient R > 0.99) were obtained at the range of 0.5-50 μg kg -1 . Limit of detection (LOD) of barbital was 0.2 μg kg -1 and that of amobarbital and phenobarbital were both 0.1 μg kg -1 (S/N ≥ 3). Limit of quatification (LOQ) was 0.5 μg kg -1 for three barbiturates (S/N ≥ 10). Satisfying recoveries ranging from 75% to 96% of the three barbiturates spiked in pork were obtained, with relative standard deviations (R.S.D.) in the range of 2.1-7.8%

  15. Simultaneous Screening of Major Flame Retardants and Plasticizers in Polymer Materials Using Pyrolyzer/Thermal Desorption Gas Chromatography Mass Spectrometry (Py/TD–GC–MS

    Directory of Open Access Journals (Sweden)

    Hiroyuki Yanagisawa

    2018-03-01

    Full Text Available This study was conducted with the aim of achieving the simultaneous screening of various additives in polymer materials by utilizing a solvent-free pyrolyzer/thermal desorption gas chromatography mass spectrometry (Py/TD-GC–MS method. As a first step to achieve this goal, simultaneous screening has been examined by selecting major substances representing plasticizers and flame retardants, such as short chain chlorinated paraffins (SCCPs, decabromodiphenyl ether (DecaBDE, hexabromocyclododecane (HBCDD, and di(2-ethylhexyl phthalate (DEHP. A quantitative MS analysis was performed to check for the peak areas and sensitivities. Since Py/TD-GC–MS is fraught with the risk of thermal degradation of the sample, temperatures during the analytical process were finely tuned for securing reliable results. The instrumental sensitivity was confirmed by the S/N ratio on each component. The detection limits of all components were less than 50 mg/kg, which are sufficiently lower than the regulatory criteria. With regard to reproducibility, a relative standard deviation (RSD of about 5% was confirmed by employing a spike recovery test on a polystyrene polymer solution containing mixed standard solution (ca. 1000 mg/kg. In conclusion, the results obtained in this study indicate that Py/TD-GC–MS is applicable for the screening of major flame retardants and plasticizers in real samples with sufficient reproducibility at regulatory levels.

  16. Determination of pharmaceuticals in sewage sludge by pressurized liquid extraction (PLE) coupled to liquid chromatography-tandem mass spectrometry (LC-MS/MS).

    Science.gov (United States)

    Radjenović, J; Jelić, A; Petrović, M; Barceló, D

    2009-03-01

    In this study, we aimed at optimizing a sensitive and reliable method for a simultaneous determination of 31 pharmaceuticals belonging to predominant therapeutic classes identified in different types of sewage sludge proceeding from conventional and advanced wastewater treatment. Freeze-dried sewage sludge was extracted by pressurized liquid extraction technique using accelerated solvent extractor Dionex 300. In order to minimize interferences with matrix components and to preconcentrate target analytes, solid phase extraction was introduced in the method as a clean-up step. The entire method was validated for linearity, precision, accuracy, and method detection limits (MDLs). The method turned out to be specific, sensitive, and reliable for the analysis of sludge of different composition, type, and retention time in the process. The developed sample preparation protocol and previously published method for LC-MS/MS analysis (Gros et al., Talanta 70:678-690, 2006) were successfully applied to monitor the target pharmaceuticals in different types of sewage sludge, i.e., primary sludge, secondary sludge, treated sludge, and sludge proceeding from pilot-scale membrane bioreactors (MBRs) operating in parallel to the conventional activated sludge treatment. Among the investigated pharmaceuticals, 20 were detected in the sludge proceeding from full-scale installations, whereas the MBR sludge concentrations were below MDLs for several compounds. The highest concentrations were recorded for treated and primary sludge. For example, the mean concentration of ibuprofen in the digested sludge was 299.3 +/- 70.9 ng g(-1) dw, whereas in the primary sludge, it was enriched up to 741.1 ng g(-1) dw. Other pharmaceuticals detected at relatively high concentrations were diclofenac, erythromycin, glibenclamide, ketoprofen, ofloxacin, azithromycin (up to 380.7, 164.2, 190.7, 336.3, 454.7, 299.6 ng g(-1) dw in the primary sludge, respectively), gemfibrozil, loratidine, and fluoxetine (up

  17. Simultaneous determination of amoxicillin and clavulanic acid in the human plasma by high performance liquid chromatography: Mass spectrometry (UPLC/MS

    Directory of Open Access Journals (Sweden)

    Ćirić Biljana

    2010-01-01

    Full Text Available Background/Aim. Quantitative analysis of amoxicillin and clavulanic acid in biological matrices requires sensitive and specific methods which allow determination of therapeutic concentration in μg/mL range. Analytical methods for determination of their concentrations in body fluids described in literature include high performance liquid chromatography coupled to UV detector (HPLC-UV and liquid chromatography-mass spectrometry (LC-MS. The aim of this study was to develop sensitive and specific ultra performance liquid chromatography/ mass spectrometry (UPLC/MS method which could be used for the spectral identification and quantification of the low concentrations of amoxicillin and clavulanic acid in the human plasma. Method. A sensitive and specific UPLC/MS method for amoxicillin and clavulanic acid determination was developed in this study. The samples were taken from the adult healthy volunteers receiving per os one tablet of amoxicillin (875 mg in combination with clavulanic acid (125 mg. Results. Plasma samples were pretreated by direct deproteinization with perchloric acid. Quantification limit of 0.01 μg/ml for both amoxicillin and clavulanic acid was achieved. The method was reproducible day by day (RSD < 7 %. Analytical recoveries for amoxicillin ranged from 98.82% to 100.9% (for concentrations of 1, 5 and 20 μg/mL, and recoveries for clavulanic acid were 99,89% to 100.1% (for concentrations of 1, 2 and 5 μg/mL. This assay was successfully applied to a pilot pharmacokinetic study in healthy volunteers after a single-oral administration of amoxicillin/ clavulanic combination. The determined plasma concentrations of both amoxicillin and clavulanic acid were in the range of the expected values upon the literature data for HPLC-UV and LC-MS methods. Conclusion. The described method provided a few advantages comparing with LC/MS-MS method. The method is faster using running time of 5 minute, has lower limit of quantification (LOQ and it

  18. Determination of Glyphosate Levels in Breast Milk Samples from Germany by LC-MS/MS and GC-MS/MS

    NARCIS (Netherlands)

    Steinborn, Angelika; Alder, Lutz; Michalski, Britta; Zomer, Paul; Bendig, Paul; Martinez, Sandra Aleson; Mol, Hans G.J.; Class, Thomas J.; Costa Pinheiro, Nathalie

    2016-01-01

    This study describes the validation and application of two independent analytical methods for the determination of glyphosate in breast milk. They are based on liquid chromatography-tandem mass spectrometry (LC-MS/MS) and gas chromatography-tandem mass spectrometry (GC-MS/MS), respectively. For

  19. Method-MS, final report 2010

    DEFF Research Database (Denmark)

    Skipperud, Lindis; Popic, Jelena M.; Roos, Per

    Radiometric determination methods, such as alpha spectrometry require long counting times when low activities are to be determined. Mass spectrometric techniques as Inductively Coupled Plasma Mass Spectrometry (ICP-MS), Thermal Ionisation Mass Spectrometry (TIMS) and Accelerator Mass Spectrometry...

  20. Isotope dilution inductively coupled plasma mass spectrometry (ID ICP-MS) for the certification of lead and cadmium in environmental standard reference materials.

    Science.gov (United States)

    Murphy, K E; Beary, E S; Rearick, M S; Vocke, R D

    2000-10-01

    Lead (Pb) and cadmium (Cd) have been determined in six new environmental standard reference materials (SRMs) using isotope dilution inductively coupled plasma mass spectrometry (ID ICP-MS). The SRMs are the following: SRM 1944, New York-New Jersey Waterway Sediment, SRMs 2583 and 2584, Trace Elements in Indoor Dust, Nominal 90 mg/kg and 10,000 mg/kg Lead, respectively, SRMs 2586 and 2587, Trace Elements in Soil Containing Lead from Paint, Nominal 500 mg/kg and 3,000 mg/kg Lead, respectively, and SRM 2782, Industrial Sludge. The capabilities of ID ICP-MS for the certification of Pb and Cd in these materials are assessed. Sample preparation and ratio measurement uncertainties have been evaluated. Reproducibility and accuracy of the established procedures are demonstrated by determination of gravimetrically prepared primary standard solutions and by comparison with isotope dilution thermal ionization mass spectrometry (ID TIMS). Material heterogeneity was readily demonstrated to be the dominant source of uncertainty in the certified values.

  1. Hyphenation of ultra performance liquid chromatography (UPLC) with inductively coupled plasma mass spectrometry (ICP-MS) for fast analysis of bromine containing preservatives

    DEFF Research Database (Denmark)

    Bendahl, Lars; Hansen, Steen Honoré; Gammelgaard, Bente

    2006-01-01

    Ultra performance liquid chromatography (UPLC) was coupled to inductively coupled plasma mass spectrometry (ICP-MS) for fast analysis of three bromine-containing preservatives, monitoring the 79Br and 81Br isotopes simultaneously. Due to the efficiency of the 1.7 microm column packing material, t...... analysis of bromine-containing preservatives in commercially available cosmetic products.......Ultra performance liquid chromatography (UPLC) was coupled to inductively coupled plasma mass spectrometry (ICP-MS) for fast analysis of three bromine-containing preservatives, monitoring the 79Br and 81Br isotopes simultaneously. Due to the efficiency of the 1.7 microm column packing material...... at an intermediate and at a high linear velocity. The precision was better than 2.2% R.S.D. and regression analysis showed that a linear response was achieved at both flow rates (R2 > 0.9993, n = 36). The analysis time was less than 4.5 min at a flow rate of 50 microL min(-1) and limits of detection...

  2. Simultaneous high-performance liquid chromatography-tandem mass spectrometry (HPLC-MS-MS) analysis of cyanide and thiocyanate from swine plasma.

    Science.gov (United States)

    Bhandari, Raj K; Manandhar, Erica; Oda, Robert P; Rockwood, Gary A; Logue, Brian A

    2014-01-01

    An analytical procedure for the simultaneous determination of cyanide and thiocyanate in swine plasma was developed and validated. Cyanide and thiocyanate were simultaneously analyzed by high-performance liquid chromatography tandem mass spectrometry in negative ionization mode after rapid and simple sample preparation. Isotopically labeled internal standards, Na(13)C(15)N and NaS(13)C(15)N, were mixed with swine plasma (spiked and nonspiked), proteins were precipitated with acetone, the samples were centrifuged, and the supernatant was removed and dried. The dried samples were reconstituted in 10 mM ammonium formate. Cyanide was reacted with naphthalene-2,3-dicarboxaldehyde and taurine to form N-substituted 1-cyano[f]benzoisoindole, while thiocyanate was chemically modified with monobromobimane to form an SCN-bimane product. The method produced dynamic ranges of 0.1-50 and 0.2-50 μM for cyanide and thiocyanate, respectively, with limits of detection of 10 nM for cyanide and 50 nM for thiocyanate. For quality control standards, the precision, as measured by percent relative standard deviation, was below 8 %, and the accuracy was within ±10 % of the nominal concentration. Following validation, the analytical procedure successfully detected cyanide and thiocyanate simultaneously from the plasma of cyanide-exposed swine.

  3. Pesticides residues in water treatment plant sludge: validation of analytical methodology using liquid chromatography coupled to Tandem mass spectrometry (LC-MS/MS)

    International Nuclear Information System (INIS)

    Moracci, Luiz Fernando Soares

    2008-01-01

    The evolving scenario of Brazilian agriculture brings benefits to the population and demands technological advances to this field. Constantly, new pesticides are introduced encouraging scientific studies with the aim of determine and evaluate impacts on the population and on environment. In this work, the evaluated sample was the sludge resulted from water treatment plant located in the Vale do Ribeira, Sao Paulo, Brazil. The technique used was the reversed phase liquid chromatography coupled to electrospray ionization tandem mass spectrometry. Compounds were previously liquid extracted from the matrix. The development of the methodology demanded data processing in order to be transformed into reliable information. The processes involved concepts of validation of chemical analysis. The evaluated parameters were selectivity, linearity, range, sensitivity, accuracy, precision, limit of detection, limit of quantification and robustness. The obtained qualitative and quantitative results were statistically treated and presented. The developed and validated methodology is simple. As results, even exploring the sensitivity of the analytical technique, the work compounds were not detected in the sludge of the WTP. One can explain that these compounds can be present in a very low concentration, can be degraded under the conditions of the water treatment process or are not completely retained by the WTP. (author)

  4. Gas chromatography-mass spectrometry (GC-MS) and liquid chromatography-mass spectrometry (LC-MS) in toxicological analysis. Studies on the detection of clobenzorex and its metabolites within a systematic toxicological analysis procedure by GC-MS and by immunoassay and studies on the detection of alpha- and beta-amanitin in urine by atmospheric pressure ionization electrospray LC-MS.

    Science.gov (United States)

    Maurer, H H; Kraemer, T; Ledvinka, O; Schmitt, C J; Weber, A A

    1997-02-07

    GC-MS is the method of choice for toxicological analysis of toxicants volatile in GC while non-volatile and/or thermally labile toxicants need LC-MS for their determination. Studies are presented on the toxicological detection of the amphetamine-like anorectic clobenzorex in urine by GC-MS after acid hydrolysis, extraction and acetylation and by fluorescence polarization immunoassay (FPIA, TDx (meth)amphetamine II). After ingestion of 60 mg of clobenzorex, the parent compound and/or its metabolites could be detected by GC-MS for up to 84 h or by FPIA for up to 60 h. Since clobenzorex shows no cross-reactivity with the used immunoassay, the N-dealkylated metabolite amphetamine is responsible for the positive TDx results. The intake of clobenzorex instead of amphetamine can be differentiated by GC-MS detection of hydroxyclobenzorex which is detectable for at least as long as amphetamine. In addition, the described GC-MS procedure allows the simultaneous detection of most of the toxicologically relevant drugs. Furthermore, studies are described on the atmospheric pressure ionization electrospray LC-MS detection of alpha- and beta-amanitin, toxic peptides of amanita mushrooms, in urine after solid-phase extraction on RP-18 columns. Using the single ion monitoring mode with the ions m/z 919 and 920 the amanitins could be detected down to 10 ng/ml of urine which allows us to diagnose intoxications with amanita mushrooms.

  5. Detection of Amyloid Beta (Aβ) Oligomeric Composition Using Matrix-Assisted Laser Desorption Ionization Mass Spectrometry (MALDI MS)

    Science.gov (United States)

    Wang, Jasmine S.-H.; Whitehead, Shawn N.; Yeung, Ken K.-C.

    2018-02-01

    The use of MALDI MS as a fast and direct method to detect the Aβ oligomers of different masses is examined in this paper. Experimental results suggest that Aβ oligomers are ionized and detected as singly charged ions, and thus, the resulting mass spectrum directly reports the oligomer size distribution. Validation experiments were performed to verify the MS data against artifacts. Mass spectra collected from modified Aβ peptides with different propensities for aggregation were compared. Generally, the relative intensities of multimers were higher from samples where oligomerization was expected to be more favorable, and vice versa. MALDI MS was also able to detect the differences in oligomeric composition before and after the incubation/oligomerization step. Such differences in sample composition were also independently confirmed with an in vitro Aβ toxicity study on primary rat cortical neurons. An additional validation was accomplished through removal of oligomers from the sample using molecular weight cutoff filters; the resulting MS data correctly reflected the removal at the expected cutoff points. The results collectively validated the ability of MALDI MS to assess the monomeric/multimeric composition of Aβ samples. [Figure not available: see fulltext.

  6. Multicenter Evaluation of the Vitek MS Matrix-Assisted Laser Desorption Ionization–Time of Flight Mass Spectrometry System for Identification of Gram-Positive Aerobic Bacteria

    Science.gov (United States)

    Burnham, Carey-Ann D.; Bythrow, Maureen; Garner, Omai B.; Ginocchio, Christine C.; Jennemann, Rebecca; Lewinski, Michael A.; Manji, Ryhana; Mochon, A. Brian; Procop, Gary W.; Richter, Sandra S.; Sercia, Linda; Westblade, Lars F.; Ferraro, Mary Jane; Branda, John A.

    2013-01-01

    Matrix-assisted laser desorption ionization–time of flight mass spectrometry (MALDI-TOF) is gaining momentum as a tool for bacterial identification in the clinical microbiology laboratory. Compared with conventional methods, this technology can more readily and conveniently identify a wide range of organisms. Here, we report the findings from a multicenter study to evaluate the Vitek MS v2.0 system (bioMérieux, Inc.) for the identification of aerobic Gram-positive bacteria. A total of 1,146 unique isolates, representing 13 genera and 42 species, were analyzed, and results were compared to those obtained by nucleic acid sequence-based identification as the reference method. For 1,063 of 1,146 isolates (92.8%), the Vitek MS provided a single identification that was accurate to the species level. For an additional 31 isolates (2.7%), multiple possible identifications were provided, all correct at the genus level. Mixed-genus or single-choice incorrect identifications were provided for 18 isolates (1.6%). Although no identification was obtained for 33 isolates (2.9%), there was no specific bacterial species for which the Vitek MS consistently failed to provide identification. In a subset of 463 isolates representing commonly encountered important pathogens, 95% were accurately identified to the species level and there were no misidentifications. Also, in all but one instance, the Vitek MS correctly differentiated Streptococcus pneumoniae from other viridans group streptococci. The findings demonstrate that the Vitek MS system is highly accurate for the identification of Gram-positive aerobic bacteria in the clinical laboratory setting. PMID:23658261

  7. Multicenter evaluation of the Vitek MS matrix-assisted laser desorption ionization-time of flight mass spectrometry system for identification of Gram-positive aerobic bacteria.

    Science.gov (United States)

    Rychert, Jenna; Burnham, Carey-Ann D; Bythrow, Maureen; Garner, Omai B; Ginocchio, Christine C; Jennemann, Rebecca; Lewinski, Michael A; Manji, Ryhana; Mochon, A Brian; Procop, Gary W; Richter, Sandra S; Sercia, Linda; Westblade, Lars F; Ferraro, Mary Jane; Branda, John A

    2013-07-01

    Matrix-assisted laser desorption ionization-time of flight mass spectrometry (MALDI-TOF) is gaining momentum as a tool for bacterial identification in the clinical microbiology laboratory. Compared with conventional methods, this technology can more readily and conveniently identify a wide range of organisms. Here, we report the findings from a multicenter study to evaluate the Vitek MS v2.0 system (bioMérieux, Inc.) for the identification of aerobic Gram-positive bacteria. A total of 1,146 unique isolates, representing 13 genera and 42 species, were analyzed, and results were compared to those obtained by nucleic acid sequence-based identification as the reference method. For 1,063 of 1,146 isolates (92.8%), the Vitek MS provided a single identification that was accurate to the species level. For an additional 31 isolates (2.7%), multiple possible identifications were provided, all correct at the genus level. Mixed-genus or single-choice incorrect identifications were provided for 18 isolates (1.6%). Although no identification was obtained for 33 isolates (2.9%), there was no specific bacterial species for which the Vitek MS consistently failed to provide identification. In a subset of 463 isolates representing commonly encountered important pathogens, 95% were accurately identified to the species level and there were no misidentifications. Also, in all but one instance, the Vitek MS correctly differentiated Streptococcus pneumoniae from other viridans group streptococci. The findings demonstrate that the Vitek MS system is highly accurate for the identification of Gram-positive aerobic bacteria in the clinical laboratory setting.

  8. Simultaneous Detection of Human C-Terminal p53 Isoforms by Single Template Molecularly Imprinted Polymers (MIPs) Coupled with Liquid Chromatography-Tandem Mass Spectrometry (LC-MS/MS)-Based Targeted Proteomics.

    Science.gov (United States)

    Jiang, Wenting; Liu, Liang; Chen, Yun

    2018-03-06

    Abnormal expression of C-terminal p53 isoforms α, β, and γ can cause the development of cancers including breast cancer. To date, much evidence has demonstrated that these isoforms can differentially regulate target genes and modulate their expression. Thus, quantification of individual isoforms may help to link clinical outcome to p53 status and to improve cancer patient treatment. However, there are few studies on accurate determination of p53 isoforms, probably due to sequence homology of these isoforms and also their low abundance. In this study, a targeted proteomics assay combining molecularly imprinted polymers (MIPs) and liquid chromatography-tandem mass spectrometry (LC-MS/MS) was developed for simultaneous quantification of C-terminal p53 isoforms. Isoform-specific surrogate peptides (i.e., KPLDGEYFTLQIR (peptide-α) for isoform α, KPLDGEYFTLQDQTSFQK (peptide-β) for isoform β, and KPLDGEYFTLQMLLDLR (peptide-γ) for isoform γ) were first selected and used in both MIPs enrichment and mass spectrometric detection. The common sequence KPLDGEYFTLQ of these three surrogate peptides was used as single template in MIPs. In addition to optimization of imprinting conditions and characterization of the prepared MIPs, binding affinity and cross-reactivity of the MIPs for each surrogate peptide were also evaluated. As a result, a LOQ of 5 nM was achieved, which was >15-fold more sensitive than that without MIPs. Finally, the assay was validated and applied to simultaneous quantitative analysis of C-terminal p53 isoforms α, β, and γ in several human breast cell lines (i.e., MCF-10A normal cells, MCF-7 and MDA-MB-231 cancer cells, and drug-resistant MCF-7/ADR cancer cells). This study is among the first to employ single template MIPs and cross-reactivity phenomenon to select isoform-specific surrogate peptides and enable simultaneous quantification of protein isoforms in LC-MS/MS-based targeted proteomics.

  9. Development of a highly sensitive and specific enzyme-linked immunosorbent assay (ELISA) for the detection of phenylethanolamine A in tissue and feed samples and confirmed by liquid chromatography tandem mass spectrometry (LC-MS/MS).

    Science.gov (United States)

    Cao, Biyun; He, Guangzhao; Yang, Hong; Chang, Huafang; Li, Shuqun; Deng, Anping

    2013-10-15

    Phenylethanolamine A (PA) is a new emerged β-adrenergic agonist illegally used as feed additives for growth promotion. In this study, a highly sensitive and specific indirect competitive enzyme-linked immunosorbent assay (ELISA) for the detection of PA in tissue and feed samples was developed and confirmed by liquid chromatography tandem mass spectrometry (LC-MS/MS). By reduction of nitryl group to amino group, the PA derivative was synthesized and coupled to carrier proteins with diazobenzidine method. The antisera obtained from four immunized rabbits were characterized in terms of sensitivity and specificity. All antisera displayed high sensitivity with IC50 values lower than 0.48 ng mL(-1). The most sensitive ELISA was established with IC50 and limit of detection (LOD) values of 0.049 ng mL(-1) and 0.003 ng mL(-1), respectively. The cross-reactivity (CR) values of the antisera with three frequently used β-adrenergic agonists (clenbuterol, salbutamol and ractopamine) were lesser than 0.39%; there was no CR of the antisera with other six compounds including two structurally related substances (isoproterenol, phenylephrine). To investigate the accuracy and precision of the assay, swine kidney, liver, meat and feed samples were fortified with PA at different content and analyzed by ELISA. Acceptable recovery rates of 92.2-113.7% and intra-assay coefficients of variation of 3.8-10.9% (n=3) were achieved. Seven spiked samples were simultaneously analyzed by ELISA and LC-MS/MS. There was a high correlation coefficient of 0.9956 (n=7) between the two methods. The proposed ELISA proven to be a feasible quantitative/screening method for PA analysis in tissue and feed samples with the properties of high sensitivity and specificity, high sample throughput and low expensive. © 2013 Elsevier B.V. All rights reserved.

  10. Tissue gadolinium deposition in hepatorenally impaired rats exposed to Gd-EOB-DTPA: evaluation with inductively coupled plasma mass spectrometry (ICP-MS).

    Science.gov (United States)

    Sato, Tomohiro; Tamada, Tsutomu; Watanabe, Shigeru; Nishimura, Hirotake; Kanki, Akihiko; Noda, Yasufumi; Higaki, Atsushi; Yamamoto, Akira; Ito, Katsuyoshi

    2015-06-01

    This study was undertaken to quantify tissue gadolinium (Gd) deposition in hepatorenally impaired rats exposed to gadolinium ethoxybenzyl diethylenetriamine pentaacetic acid (Gd-EOB-DTPA) by means of inductively coupled plasma mass spectrometry (ICP-MS) and to compare differences in Gd distribution among major organs as possible triggers for nephrogenic systemic fibrosis. Five hepatorenally impaired rats (5/6-nephrectomized, with carbon-tetrachloride-induced liver fibrosis) were injected with Gd-EOB-DTPA. Histological assessment was conducted and Gd content of the skin, liver, kidneys, lungs, heart, spleen, diaphragm, and femoral muscle was measured by inductively coupled plasma mass spectrometry (ICP-MS) at 7 days after last injection. In addition, five renally impaired rats were injected with Gd-EOB-DTPA and the degree of tissue Gd deposition was compared with that in the hepatorenally impaired rats. ICP-MS analysis revealed significantly higher Gd deposition in the kidneys, spleen, and liver (p = 0.009-0.047) in the hepatorenally impaired group (42.6 ± 20.1, 17.2 ± 6.1, 8.4 ± 3.2 μg/g, respectively) than in the renally impaired group (17.2 ± 7.7, 5.4 ± 2.1, 2.8 ± 0.7 μg/g, respectively); no significant difference was found for other organs. In the hepatorenally impaired group, Gd was predominantly deposited in the kidneys, followed by the spleen, liver, lungs, skin, heart, diaphragm, and femoral muscle. Histopathological investigation revealed hepatic fibrosis in the hepatorenally impaired group. Compared with renally impaired rats, tissue Gd deposition in hepatorenally impaired rats exposed to Gd-EOB-DTPA was significantly increased in the kidneys, spleen, and liver, probably due to the impairment of the dual excretion pathways of the urinary and biliary systems.

  11. Forensic Characterization of Liquor Samples by Gas Chromatography-Mass Spectrometry (GC-MS – A Review

    Directory of Open Access Journals (Sweden)

    Praveen K. Yadav

    2017-12-01

    Full Text Available Alcohol is a subject of forensic research across the world. The forensic characterization of alcoholic beverages is required in cases of death and crimes due to alcohol consumption. In many cases, determining the geographic origin becomes a very important part of the investigation. Therefore, it is important to develop more sensitive methods for the analysis of alcoholic beverages. In this review, an attempt has been made to summarize the work accomplished so far in the field of analysis and detection of alcoholic beverages. In this review, various sample preparation techniques for GC-MS analysis of alcoholic beverages have been discussed along with its applications. GC-MS based analysis is less time consuming, more sensitive and more accurate.   Keywords: Forensic Sciences, Alcoholic beverages, Mortality, Analysis, GC-MS

  12. Ultra-trace determination of Strontium-90 in environmental soil samples from Qatar by collision/reaction cell-inductively coupled plasma mass spectrometry (CRC-ICP-MS/MS)

    Energy Technology Data Exchange (ETDEWEB)

    Al-Meer, S. H.; Amr, M. A. [Central Laboratories Unit, Qatar University, Doha (Qatar); Helal, A.I. [Atomic Energy Authority, Cairo (Egypt); Al-Kinani, A.T. [Minstery of Environment, Doha (Qatar)

    2013-07-01

    Because of the very low level of {sup 90}Sr in the environmental soil samples and its determination by beta counting may take several weeks, we developed a procedure for ultra-trace determination of {sup 90}Sr using collision reaction cell-inductively coupled plasma tandem mass spectrometry (CRC-ICP-MS/MS, Agilent 8800). Soil samples were dried at 105 deg. C and then heated in a furnace at 550 deg. C to remove any organics present. 500 g of each soil samples were aliquoted into 2000 ml glass beakers. Each Soils samples were soaked in 2 ppm Sr solution carrier to allow determination of chemical yield. The solid to liquid ratio was 1:1. Finally the soil samples were dried at 105 deg. C. Five hundred milliliters concentrated nitric acid and 250 ml hydrochloric acid volumes were added on 500 g soil samples. The samples were digested on hot plate at 80 deg. C to prevent spraying with continuous manual mixing. The leachate solution was separated. The solids were rinsed with 500 ml deionized water, warmed on a hot plate and the leachate plus previous leachate were filtered and the total volume was reduced to 500 ml by evaporation. Final leachate volume was transferred to a centrifuge tubes. The centrifuge tubes were centrifuged at 3,500 rpm for 10 min. The leachate was transferred to a 1 L beaker and heated on a hot plate to evaporate the leachate to dryness. The reside was re-dissolved in 100 ml of 2% HNO{sub 3} and reduced by evaporation to 10 mL. The solution was measured directly by CRC-ICP-MS/MS by setting the first quadruple analyzer to m/z 90 and introducing oxygen gas into the reaction cell for elimination isobar interference from zirconium-90. The method was validated by measurements of standard reference materials and applied on environmental soil samples. The overall time requirement for the measurement of strontium-90 by CRC-ICP-MS/MS is 2 days, significantly shorter than any radioanalytical protocol currently available. (authors)

  13. Determining degree of roasting in cocoa beans by artificial neural network (ANN)-based electronic nose system and gas chromatography/mass spectrometry (GC/MS).

    Science.gov (United States)

    Tan, Juzhong; Kerr, William L

    2018-08-01

    Roasting is a critical step in chocolate processing, where moisture content is decreased and unique flavors and texture are developed. The determination of the degree of roasting in cocoa beans is important to ensure the quality of chocolate. Determining the degree of roasting relies on human specialists or sophisticated chemical analyses that are inaccessible to small manufacturers and farmers. In this study, an electronic nose system was constructed consisting of an array of gas sensors and used to detect volatiles emanating from cocoa beans roasted for 0, 20, 30 and 40 min. The several signals were used to train a three-layer artificial neural network (ANN). Headspace samples were also analyzed by gas chromatography/mass spectrometry (GC/MS), with 23 select volatiles used to train a separate ANN. Both ANNs were used to predict the degree of roasting of cocoa beans. The electronic nose had a prediction accuracy of 94.4% using signals from sensors TGS 813, 826, 822, 830, 830, 2620, 2602 and 2610. In comparison, the GC/MS predicted the degree of roasting with an accuracy of 95.8%. The electronic nose system is able to predict the extent of roasting, as well as a more sophisticated approach using GC/MS. © 2018 Society of Chemical Industry. © 2018 Society of Chemical Industry.

  14. Investigation of the aroma of commercial peach (Prunus persica L. Batsch) types by Proton Transfer Reaction-Mass Spectrometry (PTR-MS) and sensory analysis.

    Science.gov (United States)

    Bianchi, Tiago; Weesepoel, Yannick; Koot, Alex; Iglesias, Ignasi; Eduardo, Iban; Gratacós-Cubarsí, Marta; Guerrero, Luis; Hortós, Maria; van Ruth, Saskia

    2017-09-01

    The aim of this study was to investigate the aroma and sensory profiles of various types of peaches (Prunus persica L. Batsch.). Forty-three commercial cultivars comprising peaches, flat peaches, nectarines, and canning peaches (pavías) were grown over two consecutive harvest years. Fruits were assessed for chemical aroma and sensory profiles. Chemical aroma profile was obtained by proton transfer reaction-mass spectrometry (PTR-MS) and spectral masses were tentatively identified with PTR-Time of Flight-MS (PTR-Tof-MS). Sensory analysis was performed at commercial maturity considering seven aroma/flavor attributes. The four types of peaches showed both distinct chemical aroma and sensory profiles. Flat peaches and canning peaches showed most distinct patterns according to discriminant analysis. The sensory data were related to the volatile compounds by partial least square regression. γ-Hexalactone, γ-octalactone, hotrienol, acetic acid and ethyl acetate correlated positively, and benzeneacetaldehyde, trimethylbenzene and acetaldehyde negatively to the intensities of aroma and ripe fruit sensory scores. Copyright © 2017 Elsevier Ltd. All rights reserved.

  15. A novel cluster of Mycobacterium abscessus complex revealed by matrix-assisted laser desorption ionization-time-of-flight mass spectrometry (MALDI-TOF MS).

    Science.gov (United States)

    Suzuki, Hiromichi; Yoshida, Shiomi; Yoshida, Atsushi; Okuzumi, Katsuko; Fukusima, Atsuhito; Hishinuma, Akira

    2015-12-01

    Mycobacterium abscessus complex is a rapidly growing mycobacterium consisting of 3 subspecies, M. abscessus, Mycobacterium massiliense, and Mycobacterium bolletii. However, rapid and accurate species identification is difficult. We first evaluated a suitable protocol of matrix-assisted laser desorption ionization-time-of-flight mass spectrometry (MALDI-TOF MS) for distinguishing these subspecies. Then, we studied spectral signals by MALDI-TOF MS in 59 M. abscessus, 42 M. massiliense, and 2 M. bolletii. Among several specific spectral signals, 4 signals clearly differentiate M. massiliense from the other 2 subspecies, M. abscessus and M. bolletii. Moreover, 6 of the 42 M. massiliense isolates showed a spectral pattern similar to M. abscessus. These isolates correspond to the distinctive class of M. massiliense (cluster D) which is closer to M. abscessus by the previous variable number tandem repeat analysis. These results indicate that MALDI-TOF MS is not only useful for the identification of 3 subspecies of M. abscessus complex but also capable of distinguishing clusters of M. massiliense. Copyright © 2015 Elsevier Inc. All rights reserved.

  16. Characterization of Nα-Fmoc-protected dipeptide isomers by electrospray ionization tandem mass spectrometry (ESI-MS(n)): effect of protecting group on fragmentation of dipeptides.

    Science.gov (United States)

    Ramesh, M; Raju, B; Srinivas, R; Sureshbabu, V V; Vishwanatha, T M; Hemantha, H P

    2011-07-30

    A series of positional isomeric pairs of Fmoc-protected dipeptides, Fmoc-Gly-Xxx-OY/Fmoc-Xxx-Gly-OY (Xxx=Ala, Val, Leu, Phe) and Fmoc-Ala-Xxx-OY/Fmoc-Xxx-Ala-OY (Xxx=Leu, Phe) (Fmoc=[(9-fluorenylmethyl)oxy]carbonyl) and Y=CH(3)/H), have been characterized and differentiated by both positive and negative ion electrospray ionization ion-trap tandem mass spectrometry (ESI-IT-MS(n)). In contrast to the behavior of reported unprotected dipeptide isomers which mainly produce y(1)(+) and/or a(1)(+) ions, the protonated Fmoc-Xxx-Gly-OY, Fmoc-Ala-Xxx-OY and Fmoc-Xxx-Ala-OY yield significant b(1)(+) ions. These ions are formed, presumably with stable protonated aziridinone structures. However, the peptides with Gly- at the N-terminus do not form b(1)(+) ions. The [M+H](+) ions of all the peptides undergo a McLafferty-type rearrangement followed by loss of CO(2) to form [M+H-Fmoc+H](+). The MS(3) collision-induced dissociation (CID) of these ions helps distinguish the pairs of isomeric dipeptides studied in this work. Further, negative ion MS(3) CID has also been found to be useful for differentiating these isomeric peptide acids. The MS(3) of [M-H-Fmoc+H](-) of isomeric peptide acids produce c(1)(-), z(1)(-) and y(1)(-) ions. Thus the present study of Fmoc-protected peptides provides additional information on mass spectral characterization of the dipeptides and distinguishes the positional isomers. Copyright © 2011 John Wiley & Sons, Ltd.

  17. The performance and the characterization of laser ablation aerosol particle time-of-flight mass spectrometry (LAAP-ToF-MS)

    Science.gov (United States)

    Gemayel, Rachel; Hellebust, Stig; Temime-Roussel, Brice; Hayeck, Nathalie; Van Elteren, Johannes T.; Wortham, Henri; Gligorovski, Sasho

    2016-05-01

    Hyphenated laser ablation-mass spectrometry instruments have been recognized as useful analytical tools for the detection and chemical characterization of aerosol particles. Here we describe the performances of a laser ablation aerosol particle time-of-flight mass spectrometer (LAAP-ToF-MS) which was designed for aerodynamic particle sizing using two 405 nm scattering lasers and characterization of the chemical composition of single aerosol particle via ablation/ionization by a 193 nm excimer laser and detection in a bipolar time-of-flight mass spectrometer with a mass resolving power of m/Δm > 600.We describe a laboratory based optimization strategy for the development of an analytical methodology for characterization of atmospheric particles using the LAAP-ToF-MS instrument in combination with a particle generator, a differential mobility analyzer and an optical particle counter. We investigated the influence of particle number concentration, particle size and particle composition on the detection efficiency. The detection efficiency is a product of the scattering efficiency of the laser diodes and the ionization efficiency or hit rate of the excimer laser. The scattering efficiency was found to vary between 0.6 and 1.9 % with an average of 1.1 %; the relative standard deviation (RSD) was 17.0 %. The hit rate exhibited good repeatability with an average value of 63 % and an RSD of 18 %. In addition to laboratory tests, the LAAP-ToF-MS was used to sample ambient air during a period of 6 days at the campus of Aix-Marseille University, situated in the city center of Marseille, France. The optimized LAAP-ToF-MS methodology enables high temporal resolution measurements of the chemical composition of ambient particles, provides new insights into environmental science, and a new investigative tool for atmospheric chemistry and physics, aerosol science and health impact studies.

  18. High-throughput method for macrolides and lincosamides antibiotics residues analysis in milk and muscle using a simple liquid-liquid extraction technique and liquid chromatography-electrospray-tandem mass spectrometry analysis (LC-MS/MS).

    Science.gov (United States)

    Jank, Louise; Martins, Magda Targa; Arsand, Juliana Bazzan; Campos Motta, Tanara Magalhães; Hoff, Rodrigo Barcellos; Barreto, Fabiano; Pizzolato, Tânia Mara

    2015-11-01

    A fast and simple method for residue analysis of the antibiotics classes of macrolides (erythromycin, azithromycin, tylosin, tilmicosin and spiramycin) and lincosamides (lincomycin and clindamycin) was developed and validated for cattle, swine and chicken muscle and for bovine milk. Sample preparation consists in a liquid-liquid extraction (LLE) with acetonitrile, followed by liquid chromatography-electrospray-tandem mass spectrometry analysis (LC-ESI-MS/MS), without the need of any additional clean-up steps. Chromatographic separation was achieved using a C18 column and a mobile phase composed by acidified acetonitrile and water. The method was fully validated according the criteria of the Commission Decision 2002/657/EC. Validation parameters such as limit of detection, limit of quantification, linearity, accuracy, repeatability, specificity, reproducibility, decision limit (CCα) and detection capability (CCβ) were evaluated. All calculated values met the established criteria. Reproducibility values, expressed as coefficient of variation, were all lower than 19.1%. Recoveries range from 60% to 107%. Limits of detection were from 5 to 25 µg kg(-1).The present method is able to be applied in routine analysis, with adequate time of analysis, low cost and a simple sample preparation protocol. Copyright © 2015. Published by Elsevier B.V.

  19. Applicability of Gas Chromatography (GC) Coupled to Triple-Quadrupole (QqQ) Tandem Mass Spectrometry (MS/MS) for Polybrominated Diphenyl Ether (PBDE) and Emerging Brominated Flame Retardant (BFR) Determinations in Functional Foods Enriched in Omega-3.

    Science.gov (United States)

    García-Bermejo, Ángel; Mohr, Susana; Herrero, Laura; González, María-José; Gómara, Belén

    2016-09-28

    This paper reports on the optimization, characterization, and applicability of gas chromatography coupled to triple-quadrupole tandem mass spectrometry (GC-QqQ(MS/MS)) for the determination of 14 polybrominated diphenylethers (PBDEs) and 2 emerging brominated flame retardants, 1,2-bis(2,4,6-tribromophenoxy)ethane (BTBPE) and decabromodiphenylethane (DBDPE), in functional food samples. The method showed satisfactory precision and linearity with instrumental limits of detection (iLODs) ranging from 0.12 to 7.1 pg, for tri- to octa-BDEs and BTBPE, and equal to 51 and 20 pg for BDE-209 and DBDPE, respectively. The highest ΣBFR concentrations were found in fish oil supplements (924 pg/g fresh weight, fw), followed by biscuits (90 pg/g fw), vegetable oil supplements (46 pg/g fw), chicken eggs (45 pg/g fw), cow's milk (7.7 pg/g fw), and soy products (1.6 pg/g fw). BDE-47, BDE-99, and DBDPE were the most abundant compounds. Foodstuffs enriched with omega-3 presented concentrations similar to or even lower than those of conventional foods commercialized in Spain since 2000.

  20. Structural calculations and experimental detection of small Ga mS n clusters using time-of-flight mass spectrometry

    Science.gov (United States)

    BelBruno, J. J.; Sanville, E.; Burnin, A.; Muhangi, A. K.; Malyutin, A.

    2009-08-01

    Ga mS n clusters were generated by laser ablation of a solid sample of Ga 2S 3. The resulting molecules were analyzed in a time-of-flight mass spectrometer. In addition to atomic species, the spectra exhibited evidence for the existence of GaS3+, GaS4+, GaS5+, and GaS6+ clusters. The potential neutral and cationic structures of the observed Ga mS n clusters were computationally investigated using a density-functional approach. Reference is made to the kinetic pathways required for production of clusters from the starting point of the stoichiometric molecule or molecular ion. Cluster atomization enthalpies are compared with bulk values from the literature.

  1. A convenient method for calculation of ionic diffusion coefficients for accurate selected ion flow tube mass spectrometry, SIFT-MS

    Czech Academy of Sciences Publication Activity Database

    Dryahina, Kseniya; Španěl, Patrik

    2005-01-01

    Roč. 244, 2-3 (2005), s. 148-154 ISSN 1387-3806 R&D Projects: GA ČR GA202/03/0827; GA AV ČR KSK4040110 Institutional research plan: CEZ:AV0Z40400503 Keywords : mobility * diffusion * SIFT-MS * ion geometry * interaction potential Subject RIV: CF - Physical ; Theoretical Chemistry Impact factor: 2.090, year: 2005

  2. Data from mass spectrometry, NMR spectra, GC–MS of fatty acid esters produced by Lasiodiplodia theobromae

    Directory of Open Access Journals (Sweden)

    Carla C. Uranga

    2016-09-01

    Full Text Available The data described herein is related to the article with the title “Fatty acid esters produced by Lasiodiplodia theobromae function as growth regulators in tobacco seedlings” C.C. Uranga, J. Beld, A. Mrse, I. Cordova-Guerrero, M.D. Burkart, R. Hernandez-Martinez (2016 [1]. Data includes nuclear magnetic resonance spectroscopy and GC–MS data used for the identification and characterization of fatty acid esters produced by L. theobromae. GC–MS traces are also shown for incubations in defined substrate, consisting in Vogel׳s salts supplemented with either 5% grapeseed oil or 5% glucose, the two combined, or 5% fructose. Traces for incubations in the combination of 5% grapeseed oil and 5% glucose for different fungal species are also included. Images of mycelium morphology when grown in 5% glucose with or without 5% grapeseed oil are shown due to the stark difference in mycelial pigmentation in the presence of triglycerides. High concentration gradient data for the plant model Nicotiana tabacum germinated in ethyl stearate (SAEE and ethyl linoleate (LAEE is included to show the transition between growth inhibition and growth induction in N. tabacum by these compounds. Keywords: NMR, GC–MS, Fatty acid esters, Ethyl stearate, Ethyl linoleate, Growth inhibition, Growth induction

  3. Using laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS) to characterize copper, zinc and mercury along grizzly bear hair providing estimate of diet

    Energy Technology Data Exchange (ETDEWEB)

    Noël, Marie, E-mail: marie.noel@stantec.com [Stantec Consulting Ltd. 2042 Mills Road, Unit 11, Sidney BC V8L 4X2 (Canada); Christensen, Jennie R., E-mail: jennie.christensen@stantec.com [Stantec Consulting Ltd. 2042 Mills Road, Unit 11, Sidney BC V8L 4X2 (Canada); Spence, Jody, E-mail: jodys@uvic.ca [School of Earth and Ocean Sciences, Bob Wright Centre A405, University of Victoria, PO BOX 3065 STN CSC, Victoria, BC V8W 3V6 (Canada); Robbins, Charles T., E-mail: ctrobbins@wsu.edu [School of the Environment and School of Biological Sciences, Washington State University, Pullman, WA 99164-4236 (United States)

    2015-10-01

    We enhanced an existing technique, laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS), to function as a non-lethal tool in the temporal characterization of trace element exposure in wild mammals. Mercury (Hg), copper (Cu), cadmium (Cd), lead (Pb), iron (Fe) and zinc (Zn) were analyzed along the hair of captive and wild grizzly bears (Ursus arctos horribilis). Laser parameters were optimized (consecutive 2000 μm line scans along the middle line of the hair at a speed of 50 μm/s; spot size = 30 μm) for consistent ablation of the hair. A pressed pellet of reference material DOLT-2 and sulfur were used as external and internal standards, respectively. Our newly adapted method passed the quality control tests with strong correlations between trace element concentrations obtained using LA-ICP-MS and those obtained with regular solution-ICP-MS (r{sup 2} = 0.92, 0.98, 0.63, 0.57, 0.99 and 0.90 for Hg, Fe, Cu, Zn, Cd and Pb, respectively). Cross-correlation analyses revealed good reproducibility between trace element patterns obtained from hair collected from the same bear. One exception was Cd for which external contamination was observed resulting in poor reproducibility. In order to validate the method, we used LA-ICP-MS on the hair of five captive grizzly bears fed known and varying amounts of cutthroat trout over a period of 33 days. Trace element patterns along the hair revealed strong Hg, Cu and Zn signals coinciding with fish consumption. Accordingly, significant correlations between Hg, Cu, and Zn in the hair and Hg, Cu, and Zn intake were evident and we were able to develop accumulation models for each of these elements. While the use of LA-ICP-MS for the monitoring of trace elements in wildlife is in its infancy, this study highlights the robustness and applicability of this newly adapted method. - Highlights: • LA-ICP-MS provides temporal trace metal exposure information for wild grizzly bears. • Cu and Zn temporal exposures provide

  4. Using laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS) to characterize copper, zinc and mercury along grizzly bear hair providing estimate of diet

    International Nuclear Information System (INIS)

    Noël, Marie; Christensen, Jennie R.; Spence, Jody; Robbins, Charles T.

    2015-01-01

    We enhanced an existing technique, laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS), to function as a non-lethal tool in the temporal characterization of trace element exposure in wild mammals. Mercury (Hg), copper (Cu), cadmium (Cd), lead (Pb), iron (Fe) and zinc (Zn) were analyzed along the hair of captive and wild grizzly bears (Ursus arctos horribilis). Laser parameters were optimized (consecutive 2000 μm line scans along the middle line of the hair at a speed of 50 μm/s; spot size = 30 μm) for consistent ablation of the hair. A pressed pellet of reference material DOLT-2 and sulfur were used as external and internal standards, respectively. Our newly adapted method passed the quality control tests with strong correlations between trace element concentrations obtained using LA-ICP-MS and those obtained with regular solution-ICP-MS (r 2 = 0.92, 0.98, 0.63, 0.57, 0.99 and 0.90 for Hg, Fe, Cu, Zn, Cd and Pb, respectively). Cross-correlation analyses revealed good reproducibility between trace element patterns obtained from hair collected from the same bear. One exception was Cd for which external contamination was observed resulting in poor reproducibility. In order to validate the method, we used LA-ICP-MS on the hair of five captive grizzly bears fed known and varying amounts of cutthroat trout over a period of 33 days. Trace element patterns along the hair revealed strong Hg, Cu and Zn signals coinciding with fish consumption. Accordingly, significant correlations between Hg, Cu, and Zn in the hair and Hg, Cu, and Zn intake were evident and we were able to develop accumulation models for each of these elements. While the use of LA-ICP-MS for the monitoring of trace elements in wildlife is in its infancy, this study highlights the robustness and applicability of this newly adapted method. - Highlights: • LA-ICP-MS provides temporal trace metal exposure information for wild grizzly bears. • Cu and Zn temporal exposures provide

  5. Identification of clinical isolates of Aspergillus, including cryptic species, by matrix assisted laser desorption ionization time-of-flight mass spectrometry (MALDI-TOF MS).

    Science.gov (United States)

    Vidal-Acuña, M Reyes; Ruiz-Pérez de Pipaón, Maite; Torres-Sánchez, María José; Aznar, Javier

    2017-12-08

    An expanded library of matrix assisted laser desorption ionization time-of-flight mass spectrometry (MALDI-TOF MS) has been constructed using the spectra generated from 42 clinical isolates and 11 reference strains, including 23 different species from 8 sections (16 cryptic plus 7 noncryptic species). Out of a total of 379 strains of Aspergillus isolated from clinical samples, 179 strains were selected to be identified by sequencing of beta-tubulin or calmodulin genes. Protein spectra of 53 strains, cultured in liquid medium, were used to construct an in-house reference database in the MALDI-TOF MS. One hundred ninety strains (179 clinical isolates previously identified by sequencing and the 11 reference strains), cultured on solid medium, were blindy analyzed by the MALDI-TOF MS technology to validate the generated in-house reference database. A 100% correlation was obtained with both identification methods, gene sequencing and MALDI-TOF MS, and no discordant identification was obtained. The HUVR database provided species level (score of ≥2.0) identification in 165 isolates (86.84%) and for the remaining 25 (13.16%) a genus level identification (score between 1.7 and 2.0) was obtained. The routine MALDI-TOF MS analysis with the new database, was then challenged with 200 Aspergillus clinical isolates grown on solid medium in a prospective evaluation. A species identification was obtained in 191 strains (95.5%), and only nine strains (4.5%) could not be identified at the species level. Among the 200 strains, A. tubingensis was the only cryptic species identified. We demonstrated the feasibility and usefulness of the new HUVR database in MALDI-TOF MS by the use of a standardized procedure for the identification of Aspergillus clinical isolates, including cryptic species, grown either on solid or liquid media. © The Author 2017. Published by Oxford University Press on behalf of The International Society for Human and Animal Mycology. All rights reserved. For

  6. Multielement determination of rare earth elements by liquid chromatography/inductively coupled plasma atomic emission spectrometry

    International Nuclear Information System (INIS)

    Sawatari, Hideyuki; Asano, Takaaki; Hu, Xincheng; Saizuka, Tomoo; Itoh, Akihide; Hirose, Akio; Haraguchi, Hiroki

    1995-01-01

    The rapid determination of rare earth elements (REEs) has been investigated by an on-line system of high performance liquid chromatography/multichannel inductively coupled plasma atomic emission spectrometry. In the present system, all REEs could be detected simultaneously in a single chromatographic measurement without spectral interferences. Utilizing a cation exchange column and 2-hydroxy-2-methylpropanoic acid aqueous solution as the mobile phase, the detection limits of 0.4-30 ng ml -1 for all REEs were obtained. The system was applied to the determination of REEs in geological standard rock samples and rare earth impurities in high purity rare earth oxides. The REEs in standard rocks could be determined by the present HPLC/ICP-AES system without pretreatment after acid digestion, although the detection limits were not sufficient for the analysis of rare earth oxides. (author)

  7. Protein-phosphotyrosine proteome profiling by superbinder-SH2 domain affinity purification mass spectrometry, sSH2-AP-MS.

    Science.gov (United States)

    Tong, Jiefei; Cao, Biyin; Martyn, Gregory D; Krieger, Jonathan R; Taylor, Paul; Yates, Bradley; Sidhu, Sachdev S; Li, Shawn S C; Mao, Xinliang; Moran, Michael F

    2017-03-01

    Recently, "superbinder" SH2 domain variants with three amino acid substitutions (sSH2) were reported to have 100-fold or greater affinity for protein-phosphotyrosine (pY) than natural SH2 domains. Here we report a protocol in which His-tagged Src sSH2 efficiently captures pY-peptides from protease-digested HeLa cell total protein extracts. Affinity purification of pY-peptides by this method shows little bias for pY-proximal amino acid sequences, comparable to that achieved by using antibodies to pY, but with equal or higher yield. Superbinder-SH2 affinity purification mass spectrometry (sSH2-AP-MS) therefore provides an efficient and economical approach for unbiased pY-directed phospho-proteome profiling without the use of antibodies. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  8. Applications of Solid-Phase Microextraction and Gas Chromatography/Mass Spectrometry (SPME-GC/MS in the Study of Grape and Wine Volatile Compounds

    Directory of Open Access Journals (Sweden)

    Annarita Panighel

    2014-12-01

    Full Text Available Volatile compounds are responsible for the wine “bouquet”, which is perceived by sniffing the headspace of a glass, and of the aroma component (palate-aroma of the overall flavor, which is perceived on drinking. Grape aroma compounds are transferred to the wine and undergo minimal alteration during fermentation (e.g., monoterpenes and methoxypyrazines; others are precursors of aroma compounds which form in winemaking and during wine aging (e.g., glycosidically-bound volatile compounds and C13-norisoprenoids. Headspace solid phase microextraction (HS-SPME is a fast and simple technique which was developed for analysis of volatile compounds. This review describes some SPME methods coupled with gas chromatography/mass spectrometry (GC/MS used to study the grape and wine volatiles.

  9. The use of inductively coupled plasma mass spectrometry (ICP-MS) for the determination of toxic and essential elements in different types of food samples

    Science.gov (United States)

    Voica, C.; Dehelean, A.; Kovacs, M. H.

    2012-02-01

    Food is the primary source of essential elements for humans and it is an important source of exposure to toxic elements. In this context, levels of essential and toxic elements must be determined routinely in consumed food products. The content of trace elements (As, Pb, Cu, Cd, Zn, Sn, Hg) in different types of food samples (e.g. rice, bread, sugar, cheese, milk, butter, wheat, coffee, chocolate, biscuits pasta, etc.) was determined, using inductively coupled plasma mass spectrometry (ICP-MS). Trace element contents in some foods were higher than maximum permissible levels of toxic metals in human food (Cd in bread, Zn in cheese, Cu in coffee, Hg in carrots and peppers).

  10. Application of inductively coupled plasma mass spectrometry (ICP/MS) to detection of trace elements, heavy metals and radioisotopes in scalp hair

    International Nuclear Information System (INIS)

    Ozturk, Yildirim; Benderli, Cihan

    2010-01-01

    Trace element analysis of human hair has the potential to reveal retrospective information about an individual's nutritional status and exposure. As trace elements are incorporated into the hair during the growth process, longitudinal segments of the hair may reflect the body burden during the growth period. it was evaluated the potential of human hair to indicate exposure or nutritional status over time by analysing trace element profiles in single strands of human hair. By using inductively coupled plasma mass spectrometry (ICP-MS), it was achieved profiles of 43 elements in single strands of human hair. It was shown that trace element analysis along single strands of human hair can yield information about essential and toxic elements and for some elements, can be correlated with seasonal changes in diet and exposure. The information obtained from the trace element profiles of human hair in this study substantiates the potential of hair as a biomarker

  11. Mass spectrometry

    DEFF Research Database (Denmark)

    Nyvang Hartmeyer, Gitte; Jensen, Anne Kvistholm; Böcher, Sidsel

    2010-01-01

    Matrix-assisted laser desorption ionization time-of-flight mass spectrometry (MALDI-TOF MS) is currently being introduced for the rapid and accurate identification of bacteria. We describe 2 MALDI-TOF MS identification cases - 1 directly on spinal fluid and 1 on grown bacteria. Rapidly obtained...

  12. Tissue gadolinium deposition in renally impaired rats exposed to different gadolinium-based MRI contrast agents: evaluation with inductively coupled plasma mass spectrometry (ICP-MS).

    Science.gov (United States)

    Sato, Tomohiro; Ito, Katsuyoshi; Tamada, Tsutomu; Kanki, Akihiko; Watanabe, Shigeru; Nishimura, Hirotake; Tanimoto, Daigo; Higashi, Hiroki; Yamamoto, Akira

    2013-10-01

    To quantify tissue gadolinium (Gd) deposition in renally impaired rats exposed to Gd-EOB-DTPA and other Gd-based MRI contrast agents by means of inductively coupled plasma mass spectrometry (ICP-MS), and to compare the differences in distribution among major organs as possible triggers for nephrogenic systemic fibrosis (NSF). A total of 15 renally impaired rats were injected with Gd-EOB-DTPA, Gd-DTPA-BMA and Gd-HP-DO3A. Gd contents of skin, liver, kidney, lung, heart, spleen, diaphragm and femoral muscle were measured by inductively coupled plasma mass spectrometry (ICP-MS). Histological assessment was also conducted. Tissue Gd deposition in all organs was significantly higher (P=0.005~0.009) in the Gd-DTPA-BMA group than in the Gd-HP-DO3A and Gd-EOB-DTPA groups. In the Gd-DTPA-BMA group, Gd was predominantly deposited in kidney (1306±605.7μg/g), followed by skin, liver, lung, spleen, femoral muscle, diaphragm and heart. Comparing Gd-HP-DO3A and Gd-EOB-DTPA groups, Gd depositions in the kidney, liver and lung were significantly lower (P=0.009~0.011) in the Gd-EOB-DTPA group than in the Gd-HP-DO3A group although no significant differences were seen for any other organs. Gd-EOB-DTPA is a stable and safe Gd-based contrast agent (GBCA) showing lower Gd deposition in major organs in renally impaired rats, compared with other GBCAs. This fact suggests that the risk of NSF onset would be low in the use of Gd-EOB-DTPA. Copyright © 2013 Elsevier Inc. All rights reserved.

  13. Online measurement of biogenic organic acids in the boreal forest using atmospheric pressure chemical ionization mass spectrometry (APCI-MS)

    Science.gov (United States)

    Vogel, A. L.; Brüggemann, M.; ńijälä, M.; Ehn, M.; Junninen, H.; Corrigan, A. L.; Petäjä, T.; Worsnop, D. R.; Russell, L. M.; Kulmala, M.; Williams, J.; Hoffmann, T.

    2012-04-01

    Emission of biogenic volatile organic compounds (BVOCs) by vegetation in the boreal forest and their subsequent atmospheric oxidation leads to the formation of secondary organic aerosol (SOA) which has important impacts on climate and human health. Oxidation of BVOCs produces a variety of mostly unidentified species in oxygenated organic aerosol (OOA). Presently aerosol mass spectrometers (AMS) are able to determine quantitative information about the relative oxygen to carbon content of organic aerosols and thereby reveal the photochemical age and volatility of organic aerosol by distinguishing between low volatile oxygenated organic aerosol (LV-OOA), semivolatile oxygenated organic aerosol (SV-OOA) and hydrocarbon like organic aerosol (HOA)[1]. However, the AMS can usually not be used to measure and quantify single organic compounds such as individual biogenic organic marker compounds. Here we show the results of online measurements of gas and particle phase biogenic acids during HUMPPA-COPEC 2010 at Hyytiälä, Finland. This was achieved by coupling a self built miniature Versatile Aerosol Concentration Enrichment System (mVACES) as described by Geller et al. [2] with an Atmospheric Pressure Chemical Ionization Ion Trap Mass Spectrometer (APCI IT MS; Hoffmann et al., [3]). The benefits of the on-line APCI-MS are soft ionization with little fragmentation compared to AMS, high measurement frequency and less sampling artifacts than in the common procedure of taking filter samples, extraction and detection with LC-MS. Furthermore, the ion trap of the instrument allows MS/MS experiments to be performed by isolation of single m/z ratios of selected molecular species. By subsequent addition of energy, the trapped ions form characteristic fragments which enable structural insight on the molecular level. Comparison of APCI-MS data to AMS data, acquired with a C-ToF-AMS [4], revealed a good correlation coefficient for total organics and sulphate. Furthermore, data show

  14. Depth profiling of Pu, 241Am and 137Cs in soils from southern Belarus measured by ICP-MS and alpha and gamma spectrometry.

    Science.gov (United States)

    Boulyga, Sergei F; Zoriy, Myroslav; Ketterer, Michael E; Becker, J Sabine

    2003-08-01

    The depth distribution of plutonium, americium, and 137Cs originating from the 1986 accident at the Chernobyl Nuclear Power Plant (NPP) was investigated in several soil profiles in the vicinity from Belarus. The vertical migration of transuranic elements in soils typical of the 30 km relocation area around Chernobyl NPP was studied using inductively coupled plasma mass spectrometry (ICP-MS), alpha spectrometry, and gamma spectrometry. Transuranic concentrations in upper soil layers ranged from 6 x 10(-12) g g(-1) to 6 x 10(-10) g g(-1) for plutonium and from 1.8 x 10(-13) g g(-1) to 1.6 x 10(-11) g g(-1) for americium. These concentrations correspond to specific activities of (239+240)Pu of 24-2400 Bq kg(-1) and specific activity of 241Am of 23-2000 Bq kg(-1), respectively. Transuranics in turf-podzol soil migrate slowly to the deeper soil layers, thus, 80-95%, of radionuclide inventories were present in the 0-3 cm intervals of turf-podzol soils collected in 1994. In peat-marsh soil migration processes occur more rapidly than in turf-podzol and the maximum concentrations are found beneath the soil surface (down to 3-6 cm). The depth distributions of Pu and Am are essentially identical for a given soil profile. (239+240)Pu/137Cs and 241Am/137Cs activity ratios vary by up to a factor of 5 at some sites while smaller variations in these ratios were observed at a site close to Chernobyl, suggesting that 137Cs is dominantly particle associated close to Chernobyl but volatile species of 137Cs are of relatively greater importance at the distant sites.

  15. Electro-spray ionization - mass spectrometry (ESI/MS) and molecular modelling, two complementary approaches. Application to calixarenes; Electrospray - spectrometrie de masse (ESI/MS) et modelisation moleculaire, deux approches complementaires. Application aux calixarenes

    Energy Technology Data Exchange (ETDEWEB)

    Allain, F.; Virelizier, H.; Moulin, Ch. [CEA Saclay, Dept. des Procedes d' Enrichissement, 91 - Gif-sur-Yvette (France); Lamare, V.; Dozol, J.F. [CEA Cadarache, Dept. d' Entreposage et de Stockage des Dechets, 13 - Saint-Paul-lez-Durance (France)

    2001-07-01

    The molecular dynamics simulation and the experimental results obtained by the ESI/MS technique have shown that the stability of the calixarene - alkaline cation complexes is dependent of the medium. Indeed, in solution, the calixarene presents a strong affinity for cesium whereas in gaseous phase, the strong affinity is for sodium. The stability of the [calixarene+Na]{sup +} complexes depends of the nature of the medium too; these two techniques having shown that the presence of a small quantity of water in the dilution solvent stabilizes the complex. At last, calixarenes with benzo groups on their crown have an affinity for sodium which is weak in solution but strong in gaseous phase. These different results show the excellent complementarity between the two techniques. (O.M.)

  16. A rapid assay for the simultaneous determination of nicotine, cocaine and metabolites in meconium using disposable pipette extraction and gas chromatography-mass spectrometry (GC-MS).

    Science.gov (United States)

    Mozaner Bordin, Dayanne C; Alves, Marcela N R; Cabrices, Oscar G; de Campos, Eduardo G; De Martinis, Bruno Spinosa

    2014-01-01

    Drug abuse by pregnant women is considered a serious public health problem worldwide. Meconium is the first excretion in newborns and has been used as an alternative matrix to evaluate in utero drug exposure. Solid phase extraction (SPE) is widely employed to prepare and clean up samples in the field of forensic analysis. Most SPE products require large volumes of solvent, which culminates in longer sample processing times and increased cost per sample. Disposable pipette extraction (DPX) tips have been used as an alternative to traditional SPE cartridges. They combine efficient and rapid extraction with reduced solvent consumption. The purpose of this study was to develop and validate a method to determine nicotine, cotinine, cocaine, benzoylecgonine, cocaethylene and methyl ester anhydroecgonine in meconium using DPX and gas chromatography-mass spectrometry (GC-MS). Validation results indicated that extraction efficiency ranged 50-98%, accuracy 92-106%, intra-assay precision 4-12% and inter-assay precision 6-12%. Linear calibration curves resulted in R(2) values >0.99, limits of detection ranged from 2.5 to 15 ng/g and the limit of quantitation from 10 to 20 ng/g. The DPX-GC-MS method was shown to selectively analyze trace concentrations of drugs in meconium samples. Finally, the developed and validated method was applied to 50 meconium samples.

  17. Determination of different recreational drugs in sweat by headspace solid-phase microextraction gas chromatography mass spectrometry (HS-SPME GC/MS): Application to drugged drivers.

    Science.gov (United States)

    Gentili, Stefano; Mortali, Claudia; Mastrobattista, Luisa; Berretta, Paolo; Zaami, Simona

    2016-09-10

    A procedure based on headspace solid-phase microextraction (HS-SPME) coupled with gas chromatography/mass spectrometry (GC/MS) has been developed for the determination of most commonly used drugs of abuse in sweat of drivers stopped during roadside controls. DrugWipe 5A sweat screening device was used to collect sweat by a specific pad rubbed gently over forehead skin surface. The procedure involved an acid hydrolysis, a HS-SPME extraction for drugs of abuse but Δ(9)-tetrahydrocannabinol, which was directly extracted in alkaline medium HS-SPME conditions, a GC separation of analytes by a capillary column and MS detection by electron impact ionisation. The method was linear from the limit of quantification (LOQ) to 50ng drug per pad (r(2)≥0.99), with an intra- and inter-assay precision and accuracy always less than 15% and an analytical recovery between 95.1% and 102.8%, depending on the considered analyte. Using the validated method, sweat from 60 apparently intoxicated drivers were found positive to one or more drugs of abuse, showing sweat patches testing as a viable economic and simple alternative to conventional (blood and/or urine) and non conventional (oral fluid) testing of drugs of abuse in drugged drivers. Copyright © 2016 Elsevier B.V. All rights reserved.

  18. Method validation for determination of metals in Vitis labrusca L. grapevine leaf extracts by inductively coupled plasma mass spectrometry (ICP-MS

    Directory of Open Access Journals (Sweden)

    LIANE V.V. BOKOWSKI

    Full Text Available ABSTRACT Vitis labrusca L. is the main species used for wine and juice production in Brazil. The grapevine leaves can be used both as functional foods and as cheapest sources for the extraction of phenolic compounds. Besides the antioxidant activity, grapevine leaves exhibited significant anti-inflammatory activity. Therefore, the aim of this study was to develop and validate an analytical methodology to determine the metals selenium (96Se, chromium (53Cr, nickel (62Ni, cadmium (111Cd and lead (206Pb in 30 samples of grapevine leaf extracts (Vitis labrusca, Bordo cultivar using inductively coupled plasma mass spectrometry (ICP-MS. To obtain the grapevine leaf extracts the samples were milled, weighed and digested in microwave oven with nitric acid. The method showed linearity, precision, accuracy and limits of quantification and detection acceptable for INMETRO protocol validation of analytical methods. Therefore, the method using ICP-MS was developed and validated to determine metals concentrations in grapevine leaves of Vitis labrusca L. and the proposed method could be applied in routine analytical laboratory.

  19. Effects of airflow on odorants' emissions in a model pig house — A laboratory study using Proton-Transfer-Reaction Mass Spectrometry (PTR-MS)

    International Nuclear Information System (INIS)

    Saha, Chayan Kumer; Feilberg, Anders; Zhang, Guoqiang; Adamsen, Anders Peter S.

    2011-01-01

    Identification of different factors that affect emissions of gasses, including volatile organic compounds (VOCs) is necessary to develop emission abatement technology. The objectives of this research were to quantify and study temporal variation of gas emissions from a model pig house under varying ventilation rates. The used model was a 1:12.5 scale of a section of a commercial finishing pig house. The VOC concentrations at inlet, outlet, and slurry pit of the model space were measured using Proton-Transfer-Reaction Mass Spectrometry (PTR-MS). PTR-MS can measure the temporal variations of odor compounds' emission from the slurry pit in real time. The emissions of H 2 S and 14 VOCs were lower compared to real pig buildings except for ammonia, which indicated possible other sources of those compounds than the slurry in the slurry pit. The ventilation rate affected significantly on ammonia and trimethylamine emission (p 2 S) emission was independent of the ventilation rate. VFAs' emission dependency on ventilation rate increased with the increase of carbon chain. Phenols, indoles and ketones showed the positive correlation with ventilation rate to some extent. Generally, compounds with high solubility (low Henry's constant) showed stronger correlation with ventilation rates than the compounds with high Henry's constant.

  20. Gas chromatography time-of-flight mass spectrometry (GC-TOF-MS)-based metabolomics for comparison of caffeinated and decaffeinated coffee and its implications for Alzheimer's disease.

    Science.gov (United States)

    Chang, Kai Lun; Ho, Paul C

    2014-01-01

    Findings from epidemiology, preclinical and clinical studies indicate that consumption of coffee could have beneficial effects against dementia and Alzheimer's disease (AD). The benefits appear to come from caffeinated coffee, but not decaffeinated coffee or pure caffeine itself. Therefore, the objective of this study was to use metabolomics approach to delineate the discriminant metabolites between caffeinated and decaffeinated coffee, which could have contributed to the observed therapeutic benefits. Gas chromatography time-of-flight mass spectrometry (GC-TOF-MS)-based metabolomics approach was employed to characterize the metabolic differences between caffeinated and decaffeinated coffee. Orthogonal partial least squares discriminant analysis (OPLS-DA) showed distinct separation between the two types of coffee (cumulative Q(2) = 0.998). A total of 69 discriminant metabolites were identified based on the OPLS-DA model, with 37 and 32 metabolites detected to be higher in caffeinated and decaffeinated coffee, respectively. These metabolites include several benzoate and cinnamate-derived phenolic compounds, organic acids, sugar, fatty acids, and amino acids. Our study successfully established GC-TOF-MS based metabolomics approach as a highly robust tool in discriminant analysis between caffeinated and decaffeinated coffee samples. Discriminant metabolites identified in this study are biologically relevant and provide valuable insights into therapeutic research of coffee against AD. Our data also hint at possible involvement of gut microbial metabolism to enhance therapeutic potential of coffee components, which represents an interesting area for future research.

  1. A metabolic fingerprinting approach based on selected ion flow tube mass spectrometry (SIFT-MS) and chemometrics: A reliable tool for Mediterranean origin-labeled olive oils authentication.

    Science.gov (United States)

    Bajoub, Aadil; Medina-Rodríguez, Santiago; Ajal, El Amine; Cuadros-Rodríguez, Luis; Monasterio, Romina Paula; Vercammen, Joeri; Fernández-Gutiérrez, Alberto; Carrasco-Pancorbo, Alegría

    2018-04-01

    Selected Ion flow tube mass spectrometry (SIFT-MS) in combination with chemometrics was used to authenticate the geographical origin of Mediterranean virgin olive oils (VOOs) produced under geographical origin labels. In particular, 130 oil samples from six different Mediterranean regions (Kalamata (Greece); Toscana (Italy); Meknès and Tyout (Morocco); and Priego de Córdoba and Baena (Spain)) were considered. The headspace volatile fingerprints were measured by SIFT-MS in full scan with H 3 O + , NO + and O 2 + as precursor ions and the results were subjected to chemometric treatments. Principal Component Analysis (PCA) was used for preliminary multivariate data analysis and Partial Least Squares-Discriminant Analysis (PLS-DA) was applied to build different models (considering the three reagent ions) to classify samples according to the country of origin and regions (within the same country). The multi-class PLS-DA models showed very good performance in terms of fitting accuracy (98.90-100%) and prediction accuracy (96.70-100% accuracy for cross validation and 97.30-100% accuracy for external validation (test set)). Considering the two-class PLS-DA models, the one for the Spanish samples showed 100% sensitivity, specificity and accuracy in calibration, cross validation and external validation; the model for Moroccan oils also showed very satisfactory results (with perfect scores for almost every parameter in all the cases). Copyright © 2017 Elsevier Ltd. All rights reserved.

  2. Hydrogen sulfide measurement by headspace-gas chromatography-mass spectrometry (HS-GC-MS): application to gaseous samples and gas dissolved in muscle.

    Science.gov (United States)

    Varlet, Vincent; Giuliani, Nicole; Palmiere, Cristian; Maujean, Géraldine; Augsburger, Marc

    2015-01-01

    The aim of our study was to present a new headspace-gas chromatography-mass spectrometry (HS-GC-MS) method applicable to the routine determination of hydrogen sulfide (H(2)S) concentrations in biological and gaseous samples. The primary analytical drawback of the GC/MS methods for H(2)S measurement discussed in the literature was the absence of a specific H(2)S internal standard required to perform quantification. Although a deuterated hydrogen sulfide (D(2)S) standard is currently available, this standard is not often used because this standard is expensive and is only available in the gas phase. As an alternative approach, D(2)S can be generated in situ by reacting deuterated chloride with sodium sulfide; however, this technique can lead to low recovery yield and potential isotopic fractionation. Therefore, N(2)O was chosen for use as an internal standard. This method allows precise measurements of H(2)S concentrations in biological and gaseous samples. Therefore, a full validation using accuracy profile based on the β-expectation tolerance interval is presented. Finally, this method was applied to quantify H(2)S in an actual case of H(2)S fatal intoxication. © The Author 2014. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  3. Multiresidue method for detection of pesticides in beef meat using liquid chromatography coupled to mass spectrometry detection (LC-MS) after QuEChERS extraction.

    Science.gov (United States)

    Oliveira, Fabiano Aurélio da Silva; Pereira, Elba Nathália Corrêa; Gobbi, Jennifer Mattedi; Soto-Blanco, Benito; Melo, Marília Martins

    2018-01-01

    Beef meat is an important food that can be contaminated by pesticides. This study aimed to optimize a multiresidue method for identification and quantification of pesticides in beef meat by liquid chromatography coupled to mass spectrometry detection (LC-MS). The extraction and clean-up procedures were adapted from the QuECHERS method. From the 188 analytes tested, the method was validated as qualitative method for 19 compounds and as quantitative method for 152 compounds. The results were satisfactory, yielding coefficients of variation of less than 20% and recoveries ranging from 70% to 120% and expanded uncertainty of less than 50%. The quantification limit was typically 10 µg kg -1 (but 25 µg kg -1 for 12 of the compounds) and the detection limit was 5.0 µg kg -1 . Thirty-two real samples of commercialized beef meat were analyzed without any residual pesticide being found. Thus, the results showed that the multiresidue method for detecting 171 pesticides, using adapted QuECHERS for extraction and LC-MS for detection, is suitable for analyzing beef meat.

  4. Ion-pair chromatography coupled to inductively coupled plasma-mass spectrometry (IPC-ICP-MS) as a method for thiomolybdate speciation in natural waters.

    Science.gov (United States)

    Lohmayer, Regina; Reithmaier, Gloria Maria Susanne; Bura-Nakić, Elvira; Planer-Friedrich, Britta

    2015-03-17

    Molybdenum precipitates preferentially under reducing conditions; therefore, its occurrence in sediment records is used as an indicator of paleoredox conditions. Although thiomolybdates (MoO4-xSx(2-) with x = 1-4) supposedly are necessary intermediates in the process of molybdenum precipitation under anoxic conditions, there is no information about their abundance in natural environments, because of a lack of element-specific methods with sufficiently low detection limits. Here, we optimized ion-pair chromatographic separation for coupling to an inductively coupled plasma-mass spectrometry detector (IPC-ICP-MS). 2-Propanol (10%-25% gradient) replaced the previously used acetonitrile (25%-75%) as the solvent, to reduce the carbon load into the plasma. In synthetic solutions, formation of thiomolybdates was found to occur spontaneously in the presence of excess sulfide and the degree of thiolation was highest at pH 7. Excess hydroxyl led to a transformation of thiomolybdates to molybdate. Under acidic to neutral conditions, precipitation of molybdenum and hydrolysis of tetrathiomolybdate were observed. Flash-freezing was found to be suitable to stabilize tetrathiomolybdate, with 2 mM) negatively affected the detection of molybdate, which eluted mainly in the dead volume, but had no negative effect on higher thiolated molybdates. Detection limits were ∼10 nM. With the newly developed IPC-ICP-MS method, thiomolybdates were found to form spontaneously in euxinic marine waters after adding a molybdate spike and occur naturally in sulfidic geothermal waters.

  5. Thermal decomposition of foundry resins: A determination of organic products by thermogravimetry–gas chromatography–mass spectrometry (TG–GC–MS

    Directory of Open Access Journals (Sweden)

    A. Kmita

    2018-03-01

    Full Text Available The article presents the results of research on thermal decomposition of Ester-Cured Alkaline Phenolic No-Bake (ALPHASET binders used in molding technology. In the ALPHASET system phenol-formaldehyde resin of resole type is cured with a liquid mixture of esters. Under the influence of the molten metal the thermal decomposition of the binder follows, resulting in the evolution of gases, often harmful, e.g. from benzene, toluene, ethylbenzene and xylenes (BTEX or Polycyclic Aromatic Hydrocarbon (PAH groups. The identification of gases evolved during the pyrolysis of the binders was carried out and their decomposition temperatures were determined using the Thermogravimetry–Gas Chromatography–Mass Spectrometry (TG–GC–MS technique. The tests were subjected to two types of binders from different manufacturers. Among the products of pyrolysis there have been identified mainly benzene and its derivatives, and phenol and its derivatives. Compounds identified in pyrolytic gas are largely considered to be harmful to humans and the environment (some of the compounds are carcinogenic and mutagenic. The presented results of the TG–GC–MS measurements show that the applied analytic methods are feasible to perform a qualitative and also quantitative characterization of the binder samples.

  6. Attenuated Total Reflection Fourier Transform Infrared (ATR FT-IR) for Rapid Determination of Microbial Cell Lipid Content: Correlation with Gas Chromatography-Mass Spectrometry (GC-MS).

    Science.gov (United States)

    Millan-Oropeza, Aaron; Rebois, Rolando; David, Michelle; Moussa, Fathi; Dazzi, Alexandre; Bleton, Jean; Virolle, Marie-Joelle; Deniset-Besseau, Ariane

    2017-10-01

    There is a growing interest worldwide for the production of renewable oil without mobilizing agriculture lands; fast and reliable methods are needed to identify highly oleaginous microorganisms of potential industrial interest. The aim of this study was to demonstrate the relevance of attenuated total reflection (ATR) spectroscopy to achieve this goal. To do so, the total lipid content of lyophilized samples of five Streptomyces strains with varying lipid content was assessed with two classical quantitative but time-consuming methods, gas chromatography-mass spectrometry (GC-MS) and ATR Fourier transform infrared (ATR FT-IR) spectroscopy in transmission mode with KBr pellets and the fast ATR method, often questioned for its lack of reliability. A linear correlation between these three methods was demonstrated allowing the establishment of equations to convert ATR values expressed as CO/amide I ratio, into micrograms of lipid per milligram of biomass. The ATR method proved to be as reliable and quantitative as the classical GC-MS and FT-IR in transmission mode methods but faster and more reproducible than the latter since it involves far less manipulation for sample preparation than the two others. Attenuated total reflection could be regarded as an efficient fast screening method to identify natural or genetically modified oleaginous microorganisms by the scientific community working in the field of bio-lipids.

  7. A novel quantification strategy of transferrin and albumin in human serum by species-unspecific isotope dilution laser ablation inductively coupled plasma mass spectrometry (ICP-MS)

    Energy Technology Data Exchange (ETDEWEB)

    Feng, Liuxing, E-mail: fenglx@nim.ac.cn; Zhang, Dan; Wang, Jun; Shen, Dairui; Li, Hongmei

    2015-07-16

    Highlights: • Species-unspecific ID-PAGE-LA-ICP-MS was used to quantify Alb and Tf in human serum. • Addition methods of species-unspecific {sup 34}S spike were evaluated. • Isotope change conditions were investigated to reach satisfactory “isotope equilibration”. • Human serum CRM (ERM-DA470k/IFCC) was used to validate the new arrangements. • The developed method offers potential for accurate quantification of protein by ID-PAGE-LA-ICP-MS. - Abstract: Species-specific (SS) isotope dilution analysis with gel electrophoresis (GE)-laser ablation (LA)-ICP-MS is a promising technique for the quantification of particular metal-binding proteins in biological samples. However, unavailable isotopically enriched spike and metal losses in GE separation are main limitations for SS-isotope dilution PAGE-LA-ICP-MS. In this study, we report for the first time the absolute quantification of transferrin (Tf) and albumin (Alb) in human serum by non-denaturing (native) GE combined with species-unspecific isotope dilution mass spectrometry (IDMS). In order to achieve a homogeneous distribution of both protein and isotope-enriched spike (simulated isotope equilibration), immersing the protein strips with {sup 34}S spike solution after gel electrophoresis was demonstrated to be an effective way of spike addition. Furthermore, effects of immersion time and {sup 34}S spike concentration were investigated to obtain optimal conditions of the post-electrophoresis isotope dilution method. The relative mass of spike and ablated sample (m{sub sp}/m{sub sam}) in IDMS equation was calculated by standard Tf and Alb proteins, which could be applied to the quantification of Tf and Alb in ERM-DA470k/IFCC for method confirmation. The results were in agreement with the certified value with good precision and small uncertainty (1.5–3%). In this method, species-specific spike protein is not necessary and the integrity of the heteroatom-protein could be maintained in sample preparation

  8. Gram-stain plus MALDI-TOF MS (Matrix-Assisted Laser Desorption Ionization-Time of Flight Mass Spectrometry for a rapid diagnosis of urinary tract infection.

    Directory of Open Access Journals (Sweden)

    Almudena Burillo

    Full Text Available Microbiological confirmation of a urinary tract infection (UTI takes 24-48 h. In the meantime, patients are usually given empirical antibiotics, sometimes inappropriately. We assessed the feasibility of sequentially performing a Gram stain and MALDI-TOF MS mass spectrometry (MS on urine samples to anticipate clinically useful information. In May-June 2012, we randomly selected 1000 urine samples from patients with suspected UTI. All were Gram stained and those yielding bacteria of a single morphotype were processed for MALDI-TOF MS. Our sequential algorithm was correlated with the standard semiquantitative urine culture result as follows: Match, the information provided was anticipative of culture result; Minor error, the information provided was partially anticipative of culture result; Major error, the information provided was incorrect, potentially leading to inappropriate changes in antimicrobial therapy. A positive culture was obtained in 242/1000 samples. The Gram stain revealed a single morphotype in 207 samples, which were subjected to MALDI-TOF MS. The diagnostic performance of the Gram stain was: sensitivity (Se 81.3%, specificity (Sp 93.2%, positive predictive value (PPV 81.3%, negative predictive value (NPV 93.2%, positive likelihood ratio (+LR 11.91, negative likelihood ratio (-LR 0.20 and accuracy 90.0% while that of MALDI-TOF MS was: Se 79.2%, Sp 73.5, +LR 2.99, -LR 0.28 and accuracy 78.3%. The use of both techniques provided information anticipative of the culture result in 82.7% of cases, information with minor errors in 13.4% and information with major errors in 3.9%. Results were available within 1 h. Our serial algorithm provided information that was consistent or showed minor errors for 96.1% of urine samples from patients with suspected UTI. The clinical impacts of this rapid UTI diagnosis strategy need to be assessed through indicators of adequacy of treatment such as a reduced time to appropriate empirical treatment or

  9. A novel quantification strategy of transferrin and albumin in human serum by species-unspecific isotope dilution laser ablation inductively coupled plasma mass spectrometry (ICP-MS)

    International Nuclear Information System (INIS)

    Feng, Liuxing; Zhang, Dan; Wang, Jun; Shen, Dairui; Li, Hongmei

    2015-01-01

    Highlights: • Species-unspecific ID-PAGE-LA-ICP-MS was used to quantify Alb and Tf in human serum. • Addition methods of species-unspecific 34 S spike were evaluated. • Isotope change conditions were investigated to reach satisfactory “isotope equilibration”. • Human serum CRM (ERM-DA470k/IFCC) was used to validate the new arrangements. • The developed method offers potential for accurate quantification of protein by ID-PAGE-LA-ICP-MS. - Abstract: Species-specific (SS) isotope dilution analysis with gel electrophoresis (GE)-laser ablation (LA)-ICP-MS is a promising technique for the quantification of particular metal-binding proteins in biological samples. However, unavailable isotopically enriched spike and metal losses in GE separation are main limitations for SS-isotope dilution PAGE-LA-ICP-MS. In this study, we report for the first time the absolute quantification of transferrin (Tf) and albumin (Alb) in human serum by non-denaturing (native) GE combined with species-unspecific isotope dilution mass spectrometry (IDMS). In order to achieve a homogeneous distribution of both protein and isotope-enriched spike (simulated isotope equilibration), immersing the protein strips with 34 S spike solution after gel electrophoresis was demonstrated to be an effective way of spike addition. Furthermore, effects of immersion time and 34 S spike concentration were investigated to obtain optimal conditions of the post-electrophoresis isotope dilution method. The relative mass of spike and ablated sample (m sp /m sam ) in IDMS equation was calculated by standard Tf and Alb proteins, which could be applied to the quantification of Tf and Alb in ERM-DA470k/IFCC for method confirmation. The results were in agreement with the certified value with good precision and small uncertainty (1.5–3%). In this method, species-specific spike protein is not necessary and the integrity of the heteroatom-protein could be maintained in sample preparation process. Moreover, the

  10. Exploiting dynamic reaction cell inductively coupled plasma mass spectrometry (DRC-ICP-MS) for sequential determination of trace elements in blood using a dilute-and-shoot procedure

    International Nuclear Information System (INIS)

    Lemos Batista, Bruno; Lisboa Rodrigues, Jairo; Andrade Nunes, Juliana; Oliveira Souza, Vanessa Cristina de; Barbosa, Fernando

    2009-01-01

    Inductively coupled plasma mass spectrometry with quadrupole (q-ICP-MS) and dynamic reaction cell (DRC-ICP-MS) were evaluated for sequential determination of As, Cd, Co, Cr, Cu, Mn, Pb, Se, Tl, V and Zn in blood. The method requires as little as 100 μL of blood. Prior to analysis, samples (100 μL) were diluted 1:50 in a solution containing 0.01% (v/v) Triton X-100 and 0.5% (v/v) nitric acid. The use of the DRC was only mandatory for Cr, Cu, V and Zn. For the other elements the equipment may be operated in a standard mode (q-ICP-MS). Ammonia was used as reaction gas. Selection of best flow rate of ammonium gas and optimization of the quadrupole dynamic band-pass tuning parameter (RPq) were carried out, using a ovine base blood for Cr and V and a synthetic matrix solution (SMS) for Zn and Cu diluted 1:50 and spiked to contain 1 μg L -1 of each element. Method detection limits (3 s) for 75 As, 114 Cd, 59 Co, 51 Cr, 63 Cu 55 Mn, 208 Pb, 82 Se, 205 Tl, 51 V, and 64 Zn were 14.0, 3.0, 11.0, 7.0, 280, 9.0, 3.0, 264, 0.7, 6.0 and 800 ng L -1 , respectively. Method validation was accomplished by the analysis of blood Reference Materials produced by the L'Institut National de Sante Publique du Quebec (Canada).

  11. Method Development for Binding Media Analysis in Painting Cross-Sections by Desorption Electrospray Ionization-Mass Spectrometry (DESI-MS).

    Science.gov (United States)

    Watts, Kristen; Lagalante, Anthony

    2018-06-06

    Art conservation science is in need of a relatively nondestructive way of rapidly identifying the binding media within a painting cross-section and isolating binding media to specific layers within the cross-section. Knowledge of the stratigraphy of cross-sections can be helpful for removing possible unoriginal paint layers on the artistic work. Desorption electrospray ionization-mass spectrometry (DESI-MS) was used in ambient mode to study cross-sections from mock-up layered paint samples and samples from a 17th century baroque painting. The DESI spray was raster scanned perpendicular to the cross-section layers to maximize lateral resolution then analyzed with a triple quadrupole mass analyzer in linear ion trap mode. From these scans, isobaric mass maps were created to map the locations of masses indicative of particular binding media onto the cross-sections. Line paint-outs of pigments in different binding media showed specific and unique ions to distinguish between the modern acrylic media and the lipid containing binding media. This included: OP (EO) 9 surfactant in positive ESI for acrylic (m/z 621), and oleic (m/z 281), stearic (m/z 283), and azelaic (m/z 187) acids in negative ESI for oil and egg tempera. DESI-MS maps of mock-up cross-sections of layered pigmented binding media showed correlation between these ions and the layers with a spatial resolution of 100 μm. DESI-MS is effective in monitoring binding media within an intact painting cross-section via mass spectrometric methods. This includes distinguishing between lipid-containing and modern binding materials present in a known mockup cross section matrix as well as identifying lipid binding media in a 17th century baroque era painting. This article is protected by copyright. All rights reserved.

  12. A validated inductively coupled plasma mass spectrometry (ICP-MS) method for the quantification of total platinum content in plasma, plasma ultrafiltrate, urine and peritoneal fluid.

    Science.gov (United States)

    Lemoine, Lieselotte; Thijssen, Elsy; Noben, Jean-Paul; Adriaensens, Peter; Carleer, Robert; Speeten, Kurt Van der

    2018-04-15

    Oxaliplatin is a platinum (Pt) 1 containing antineoplastic agent that is applied in current clinical practice for the treatment of colon and appendiceal neoplasms. A fully validated, highly sensitive, high throughput inductively coupled plasma mass spectrometry (ICP-MS) method is provided to quantify the total Pt content in plasma, plasma ultrafiltrate, urine and peritoneal fluid. In this ICP-MS approach, the only step of sample preparation is a 1000-fold dilution in 0.5% nitric acid, allowing the analysis of 17 samples per hour. Detection of Pt was achieved over a linear range of 0.01-100 ng/mL. The limit of quantification was 18.0 ng/mL Pt in plasma, 8.0 ng/mL in ultrafiltrate and 6.1 ng/mL in urine and peritoneal fluid. The ICP-MS method was further validated for inter-and intraday precision and accuracy (≤15%), recovery, robustness and stability. Short-term storage of the biofluids, for 14 days, can be performed at -4 °C, -24 °C and -80 °C. As to long-term stability, up to 5 months, storage at -80 °C is encouraged. Furthermore, a timeline assessing the total and unbound Pt fraction in plasma and ultrafiltrate over a period of 45 h is provided. Following an incubation period of 5 h at 37 °C, 19-21% of Pt was recovered in the ultrafiltrate, emphasizing the extensive and rapid binding of oxaliplatin-derived Pt to plasma proteins. The described method can easily be implemented in a routine setting for pharmacokinetic studies in patients treated with oxaliplatin-based hyperthermic intraperitoneal perioperative chemotherapy. Copyright © 2018 Elsevier B.V. All rights reserved.

  13. Establishment of methodology for determination of 93Zr in radioactive wastes by Liquid Scintillation Counting (LSC) and Inductively Coupled Plasma Mass Spectrometry (ICP-MS)

    International Nuclear Information System (INIS)

    Oliveira, Thiago Cesar de

    2014-01-01

    The zirconium-93 is a long-lived pure β-particle-emitting radionuclide produced from 235 U fission and from neutron activation of the stable isotope 92 Zr and thus occurring as one of the radionuclides found in nuclear reactors. Due to its long half life, 93 Zr is one of the radionuclides of interest for the performance of assessment studies of waste storage or disposal. Measurement of 93 Zr is difficult owing to its trace level concentration and its low activity in nuclear wastes and further because its certified standards are not frequently available. The aim of this work was to develop a selective radiochemical separation methodology for the determination of 93 Zr in nuclear waste and analyze it by Liquid Scintillation Counting (LSC) and Inductively Coupled Plasma Mass Spectrometry (ICP-MS). To set up the radiochemical separation procedure for zirconium, a tracer solution of 95 Zr and its 724 keV γ-ray measurements by γ- spectrometry were used in order to follow the behavior of zirconium during the radiochemical separation. For the LSC technique a 55 Fe solution, which is one of the major interfering measures zirconium, was used to verify the decontamination factor during the separation process. The efficiency detection for 63 Ni was used to determination of 93 Zr activity in the matrices analyzed. The limit of detection of the 0.05 Bq 1 −1 was obtained for 63 Ni standard solutions by using a sample:cocktail ratio of 3:17 mL for Optiphase Hisafe 3 cocktail. For the ICP-MS technique a zirconium stable solution was used to verify the zirconium behavior and recovery during radiochemical separation and a solution of Ba, Co, Eu, Fe, Mn, Nb, Sr and Y was used to verify the decontamination factor during the separation process. A standard solution 93 Nb as isotope for determining the 93 Zr by ICP-MS was used for calibration and analysis. The detection limit of 0.039 ppb was obtained for the standard solution of zirconium. Then, the protocol was applied to low level

  14. Profiling of ornithine lipids in bacterial extracts of Rhodobacter sphaeroides by reversed-phase liquid chromatography with electrospray ionization and multistage mass spectrometry (RPLC-ESI-MS(n)).

    Science.gov (United States)

    Granafei, Sara; Losito, Ilario; Trotta, Massimo; Italiano, Francesca; de Leo, Vincenzo; Agostiano, Angela; Palmisano, Francesco; Cataldi, Tommaso R I

    2016-01-15

    Ornithine lipids (OLs), a sub-group of the large (and of emerging interest) family of lipoamino acids of bacterial origin, contain a 3-hydroxy fatty acyl chain linked via an amide bond to the α-amino group of ornithine and via an ester bond to a second fatty acyl chain. OLs in extracts of Rhodobacter sphaeroides (R. sphaeroides) were investigated by high-performance reversed phase liquid chromatography (RPLC) with electrospray ionization mass spectrometry (ESI-MS) in negative ion mode using a linear ion trap (LIT). The presence of OLs bearing both saturated (i.e, 16:0, 17:0, 18:0, 19:0 and 20:0) and unsaturated chains (i.e., 18:1, 19:1, 19:2 and 20:1) was ascertained and their identification, even for isomeric, low abundance and partially co-eluting species, was achieved by low-energy collision induced dissociation (CID) multistage mass spectrometry (MS(n), n = 2-4). OLs signatures found in two R. sphaeroides strains, i.e., wild type 2.4.1 and mutant R26, were examined and up to 16 and 17 different OL species were successfully identified, respectively. OLs in both bacterial strains were characterized by several combinations of fatty chains on ester-linked and amide-linked 3-OH fatty acids. Multistage MS spectra of monoenoic amide-linked 3-OH acyl chains, allowed the identification of positional isomer of OL containing 18:1 (i.e. 9-octadecenoic) and 20:1 (i.e. 11-eicosenoic) fatty acids. The most abundant OL ([M-H](-) at m/z 717.5) in R. sphaeroides R26 was identified as OL 3-OH 20:1/19:1 (i.e., 3-OH-eicosenoic acid amide-linked to ornithine and esterified to a nonadecenoic chain containing a cyclopropane ring). An unusual OL (m/z 689.5 for the [M-H](-) ion), most likely containing a cyclopropene ester-linked acyl chain (i.e., OL 3-OH 18:0/19:2), was retrieved only in the carotenoidless mutant strain R26. Based on the biosynthetic pathways already known for cyclopropa(e)ne ring-including acyl chains, a plausible explanation was invoked for the enzymatic

  15. Determination of selenium in red blood cells by inductively coupled plasma mass spectrometry (ICP-MS) after microwave digestion

    International Nuclear Information System (INIS)

    Tinggi, U.; Francis, R.; Shanin, M.; Scheelings, P.; Gianduzzo, T.; Nicol, D.

    2004-01-01

    Selenium is an essential trace element and its levels in blood have been widely used for assessing Se status in humans. A suitable method for the determination of Se in red blood cells (RBC) using ICP-MS after microwave digestion was developed. The blood samples were obtained from patients with benign prostatic hyperplasia (BPH), who attended urology clinics at the Princess Alexandra hospital, Brisbane, Australia. No apparent polyatomic and matrix interferences were encountered when 82 Se isotope was used for the analysis of Se levels in RBC. Whole Blood Seronorm Trace Elements (SERO, Norway) and dogfish muscle (DORM-1, NRCC) were used as reference materials for method validation. The method was rapid and accurate, and ideal for routine analysis of Se in RBC, and in particular for assessing of Se status in humans. (author)

  16. Electro-spray ionization - mass spectrometry (ESI/MS) and molecular modelling, two complementary approaches. Application to calixarenes

    International Nuclear Information System (INIS)

    Allain, F.; Virelizier, H.; Moulin, Ch.; Lamare, V.; Dozol, J.F.

    2001-01-01

    The molecular dynamics simulation and the experimental results obtained by the ESI/MS technique have shown that the stability of the calixarene - alkaline cation complexes is dependent of the medium. Indeed, in solution, the calixarene presents a strong affinity for cesium whereas in gaseous phase, the strong affinity is for sodium. The stability of the [calixarene+Na] + complexes depends of the nature of the medium too; these two techniques having shown that the presence of a small quantity of water in the dilution solvent stabilizes the complex. At last, calixarenes with benzo groups on their crown have an affinity for sodium which is weak in solution but strong in gaseous phase. These different results show the excellent complementarity between the two techniques. (O.M.)

  17. Development of new applications of inductively coupled plasma mass spectrometry (ICP-MS) hyphenated with different sample introduction systems

    OpenAIRE

    Ugarte Baztán, Ana

    2014-01-01

    225 p. : il. Texto en español con conclusiones en inglés Hoy en día, la espectrometría de masas con plasma de acoplamiento inductivo (ICP-MS) es una de las técnicas más potentes y versátiles para el análisis de elementos traza dada su robustez y bajos límites de detección. En el presente trabajo se pretende ampliar el abanico de aplicaciones de esta técnica desarrollando nuevas combinaciones de la misma a distintos sistemas de introducción de muestra. En primera lugar, se presenta el a...

  18. Sulphur fertilization influences the sulphur species composition in Allium sativum: sulphomics using HPLC-ICPMS/MS-ESI-MS/MS.

    Science.gov (United States)

    Raab, Andrea; Ronzan, Marilena; Feldmann, Joerg

    2017-10-18

    Garlic (A. sativum) contains a large number of small sulphur (S)-containing metabolites, which are important for its taste and smell and vary with A. sativum variety and growth conditions. This study was designed to investigate the influence of different sulphur-fertilization regimes on low molecular weight S-species by attempting the first sulphur mass balance in A. sativum roots and bulbs using HPLC-ICPMS/MS-ESI-MS/MS. Species unspecific quantification of acid soluble S-containing metabolites was achieved using HPLC-ICP-MS/MS. For identification of the compounds, high resolution ESI-MS (Orbitrap LTQ and q-TOF) was used. The plants contained up to 54 separated sulphur-containing compounds, which constitute about 80% of the total sulphur present in A. sativum. The roots and bulbs of A. sativum contained the same compounds, but not necessarily the same amounts and proportions. The S-containing metabolites in the roots reacted more sensitively to manipulations of sulphur fertilization than those compounds in the bulbs. In addition to known compounds (e.g. γ-glutamyl-S-1-propenylcysteine) we were able to identify and partially quantify 31 compounds. Three as yet undescribed S-containing compounds were also identified and quantified for the first time. Putative structures were assigned to the oxidised forms of S-1-propenylmercaptoglutathione, S-2-propenylmercaptoglutathione, S-allyl/propenyl-containing PC-2 and 2-amino-3-[(2-carboxypropyl)sulfanyl]propanoic acid. The parallel use of ICP-MS/MS as a sulphur-specific detector and ESI-MS as a molecular detector simplifies the identification and quantification of sulphur containing metabolites without species specific standards. This non-target analysis approach enables a mass balance approach and identifies the occurrence of the so far unidentified organosulphur compounds. The experiments showed that the sulphur-fertilization regime does not influence sulphur-speciation, but the concentration of some S

  19. Analysis of carbohydrates in Fusarium verticillioides using size-exclusion HPLC – DRI and direct analysis in real time ionization – time-of-flight – mass spectrometry (DART-MS)

    Science.gov (United States)

    Direct analysis in real time ionization – time-of-flight – mass spectrometry (DART-MS) and size-exclusion HPLC – DRI are used, respectively, to qualitatively and quantitatively determine the carbohydrates extracted from the corn rot fungus Fusarium verticillioides. In situ permethylation in the DART...

  20. Analysis of plutonium isotope ratios including 238Pu/239Pu in individual U-Pu mixed oxide particles by means of a combination of alpha spectrometry and ICP-MS.

    Science.gov (United States)

    Esaka, Fumitaka; Yasuda, Kenichiro; Suzuki, Daisuke; Miyamoto, Yutaka; Magara, Masaaki

    2017-04-01

    Isotope ratio analysis of individual uranium-plutonium (U-Pu) mixed oxide particles contained within environmental samples taken from nuclear facilities is proving to be increasingly important in the field of nuclear safeguards. However, isobaric interferences, such as 238 U with 238 Pu and 241 Am with 241 Pu, make it difficult to determine plutonium isotope ratios in mass spectrometric measurements. In the present study, the isotope ratios of 238 Pu/ 239 Pu, 240 Pu/ 239 Pu, 241 Pu/ 239 Pu, and 242 Pu/ 239 Pu were measured for individual Pu and U-Pu mixed oxide particles by a combination of alpha spectrometry and inductively coupled plasma mass spectrometry (ICP-MS). As a consequence, we were able to determine the 240 Pu/ 239 Pu, 241 Pu/ 239 Pu, and 242 Pu/ 239 Pu isotope ratios with ICP-MS after particle dissolution and chemical separation of plutonium with UTEVA resins. Furthermore, 238 Pu/ 239 Pu isotope ratios were able to be calculated by using both the 238 Pu/( 239 Pu+ 240 Pu) activity ratios that had been measured through alpha spectrometry and the 240 Pu/ 239 Pu isotope ratios determined through ICP-MS. Therefore, the combined use of alpha spectrometry and ICP-MS is useful in determining plutonium isotope ratios, including 238 Pu/ 239 Pu, in individual U-Pu mixed oxide particles. Copyright © 2016 Elsevier B.V. All rights reserved.

  1. Development of a multi-residue analytical methodology based on liquid chromatography-tandem mass spectrometry (LC-MS/MS) for screening and trace level determination of pharmaceuticals in surface and wastewaters.

    Science.gov (United States)

    Gros, Meritxell; Petrović, Mira; Barceló, Damiá

    2006-11-15

    This paper describes development, optimization and validation of a method for the simultaneous determination of 29 multi-class pharmaceuticals using off line solid phase extraction (SPE) followed by liquid chromatography-triple quadrupole mass spectrometry (LC-MS-MS). Target compounds include analgesics and non-steroidal anti-inflammatories (NSAIDs), lipid regulators, psychiatric drugs, anti-histaminics, anti-ulcer agent, antibiotics and beta-blockers. Recoveries obtained were generally higher than 60% for both surface and wastewaters, with exception of several compounds that yielded lower, but still acceptable recoveries: ranitidine (50%), sotalol (50%), famotidine (50%) and mevastatin (34%). The overall variability of the method was below 15%, for all compounds and all tested matrices. Method detection limits (MDL) varied between 1 and 30ng/L and from 3 to 160ng/L for surface and wastewaters, respectively. The precision of the method, calculated as relative standard deviation (R.S.D.), ranged from 0.2 to 6% and from 1 to 11% for inter and intra-day analysis, respectively. A detailed study of matrix effects was performed in order to evaluate the suitability of different calibration approaches (matrix-matched external calibration, internal calibration, extract dilution) to reduce analyte suppression or enhancement during instrumental analysis. The main advantages and drawbacks of each approach are demonstrated, justifying the selection of internal standard calibration as the most suitable approach for our study. The developed analytical method was successfully applied to the analysis of pharmaceutical residues in WWTP influents and effluents, as well as in river water. For both, river and wastewaters, the most ubiquitous compounds belonged to the group of anti-inflammatories and analgesics, antibiotics, the lipid regulators being acetaminophen, trimethoprim, ibuprofen, ketoprofen, atenolol, propranolol, mevastatin, carbamazepine and ranitidine the most frequently

  2. Alignment, orientation, and Coulomb explosion of difluoroiodobenzene studied with the pixel imaging mass spectrometry (PImMS) camera.

    Science.gov (United States)

    Amini, Kasra; Boll, Rebecca; Lauer, Alexandra; Burt, Michael; Lee, Jason W L; Christensen, Lauge; Brauβe, Felix; Mullins, Terence; Savelyev, Evgeny; Ablikim, Utuq; Berrah, Nora; Bomme, Cédric; Düsterer, Stefan; Erk, Benjamin; Höppner, Hauke; Johnsson, Per; Kierspel, Thomas; Krecinic, Faruk; Küpper, Jochen; Müller, Maria; Müller, Erland; Redlin, Harald; Rouzée, Arnaud; Schirmel, Nora; Thøgersen, Jan; Techert, Simone; Toleikis, Sven; Treusch, Rolf; Trippel, Sebastian; Ulmer, Anatoli; Wiese, Joss; Vallance, Claire; Rudenko, Artem; Stapelfeldt, Henrik; Brouard, Mark; Rolles, Daniel

    2017-07-07

    Laser-induced adiabatic alignment and mixed-field orientation of 2,6-difluoroiodobenzene (C 6 H 3 F 2 I) molecules are probed by Coulomb explosion imaging following either near-infrared strong-field ionization or extreme-ultraviolet multi-photon inner-shell ionization using free-electron laser pulses. The resulting photoelectrons and fragment ions are captured by a double-sided velocity map imaging spectrometer and projected onto two position-sensitive detectors. The ion side of the spectrometer is equipped with a pixel imaging mass spectrometry camera, a time-stamping pixelated detector that can record the hit positions and arrival times of up to four ions per pixel per acquisition cycle. Thus, the time-of-flight trace and ion momentum distributions for all fragments can be recorded simultaneously. We show that we can obtain a high degree of one-and three-dimensional alignment and mixed-field orientation and compare the Coulomb explosion process induced at both wavelengths.

  3. Frequency-Modulated Continuous Flow Analysis Electrospray Ionization Mass Spectrometry (FM-CFA-ESI-MS) for Sample Multiplexing.

    Science.gov (United States)

    Filla, Robert T; Schrell, Adrian M; Coulton, John B; Edwards, James L; Roper, Michael G

    2018-02-20

    A method for multiplexed sample analysis by mass spectrometry without the need for chemical tagging is presented. In this new method, each sample is pulsed at unique frequencies, mixed, and delivered to the mass spectrometer while maintaining a constant total flow rate. Reconstructed ion currents are then a time-dependent signal consisting of the sum of the ion currents from the various samples. Spectral deconvolution of each reconstructed ion current reveals the identity of each sample, encoded by its unique frequency, and its concentration encoded by the peak height in the frequency domain. This technique is different from other approaches that have been described, which have used modulation techniques to increase the signal-to-noise ratio of a single sample. As proof of concept of this new method, two samples containing up to 9 analytes were multiplexed. The linear dynamic range of the calibration curve was increased with extended acquisition times of the experiment and longer oscillation periods of the samples. Because of the combination of the samples, salt had little effect on the ability of this method to achieve relative quantitation. Continued development of this method is expected to allow for increased numbers of samples that can be multiplexed.

  4. Identification of volatile organic compounds (VOCs in plastic products using gas chromatography and mass spectrometry (GC/MS

    Directory of Open Access Journals (Sweden)

    Nerlis Pajaro-Castro

    2014-10-01

    Full Text Available Plastic materials are widely used in daily life. They contain a wide range of compounds with low molecular mass, including monomeric and oligomeric residues of polymerization, solvent-related chemicals residues, and various additives. Plastic products made of expanded polystyrene (EPS are currently employed as food containers. This study therefore sought to identify volatile organic compounds released by EPS from food packages and utensils used in Cartagena, Colombia. EPS-based plates, food and soup containers were subjected to various temperatures and released chemicals captured by solid phase microextraction, followed by on-column thermal desorption and gas chromatography/mass spectrometry analysis. The results revealed the presence of at least 30 different compounds in the EPS-based products examined; the most frequently found were benzaldehyde, styrene, ethylbenzene and tetradecane. The release of these molecules was temperature-dependent. It is therefore advisable to regulate the use of EPS products which may be subjected to heating in order to protect human health by decreasing the exposure to these chemicals.

  5. Thermogravimetric analysis-mass spectrometry (TG-MS) of selected Chinese palygorskites-Implications for structural water

    International Nuclear Information System (INIS)

    Cheng, Hongfei; Yang, Jing; Frost, Ray L.

    2011-01-01

    Four Chinese palygorskites clay minerals have been analysed by thermogravimetric analysis-mass spectrometry and X-ray diffraction. The structural water of the palygorskite dehydrates in the temperature range of 30-625 o C, as shown in the thermogravimetric analysis and mass spectrometric curves. The mass spectrometric curves combined the differential thermogravimetric curves enable the detailed determination of the main dehydration steps. The results show that the dehydration occurs in four main steps: (a) elimination of interparticle water and partial zeolitic water at below 110 o C, (b) release of the rest part of zeolitic water from the structural layer of palygorskite at about 160 o C, (c) dehydration of one part of bound water at about 340 o C and (d) loss of the rest part of bound water at around 450 o C. The temperatures of dehydration of the palygorskite minerals are found to be influenced by the geological environment and the amount and kind of impurities. The evolved gases in the decomposition process are various because of the different amounts and kind of impurities. It is also found that decarbonization takes place at around 600 o C due to the decomposition of calcite and dolomite impurities in these minerals. It is evident by the mass spectrometric curve that the water is given out from the samples and carbon dioxide originates from the impurity calcite and dolomite.

  6. Development of protein biomarkers in cerebrospinal fluid for secondary progressive multiple sclerosis using selected reaction monitoring mass spectrometry (SRM-MS

    Directory of Open Access Journals (Sweden)

    Jia Yan

    2012-07-01

    Full Text Available Abstract Background Multiple sclerosis (MS is a chronic inflammatory disorder of the central nervous system (CNS. It involves damage to the myelin sheath surrounding axons and to the axons themselves. MS most often presents with a series of relapses and remissions but then evolves over a variable period of time into a slowly progressive form of neurological dysfunction termed secondary progressive MS (SPMS. The reasons for this change in clinical presentation are unclear. The absence of a diagnostic marker means that there is a lag time of several years before the diagnosis of SPMS can be established. At the same time, understanding the mechanisms that underlie SPMS is critical to the development of rational therapies for this untreatable stage of the disease. Results Using high performance liquid chromatography-coupled mass spectrometry (HPLC; we have established a highly specific and sensitive selected reaction monitoring (SRM assay. Our multiplexed SRM assay has facilitated the simultaneous detection of surrogate peptides originating from 26 proteins present in cerebrospinal fluid (CSF. Protein levels in CSF were generally ~200-fold lower than that in human sera. A limit of detection (LOD was determined to be as low as one femtomol. We processed and analysed CSF samples from a total of 22 patients with SPMS, 7 patients with SPMS treated with lamotrigine, 12 patients with non-inflammatory neurological disorders (NIND and 10 healthy controls (HC for the levels of these 26 selected potential protein biomarkers. Our SRM data found one protein showing significant difference between SPMS and HC, three proteins differing between SPMS and NIND, two proteins between NIND and HC, and 11 protein biomarkers showing significant difference between a lamotrigine-treated and untreated SPMS group. Principal component analysis (PCA revealed that these 26 proteins were correlated, and could be represented by four principal components. Overall, we established an

  7. Extraction and Chemical Compounds Identification of Red Rice Bran Oil Using Gas Chromatography – Mass Spectrometry (GC-MS Method

    Directory of Open Access Journals (Sweden)

    Hoo Sheren Hartono

    2017-09-01

    Full Text Available The objectives of the study are to obtain optimum yield of extraction red rice bran oil, todetermine the physico-chemical characteristics, and componen coumpounds. Data was analyzedusing Nir Parametric Statistics by Friedmann test. The result showed the optimum extractionresults was obtained by the ratio of substrate : solvent of 1: 8 and the oil yield was 12.31 ±0.325%. The physico properties of red rice bran oil were greenish brown colour, with a densityranged from 0.908 ± 0.014 to 0.922 ± 0.014 (g/mL, and the water content ranged from 0.87 ± 0.06to 0.91 ± 0.02 %. The chemical properties of red rice bran oil were: the acid number ranged from116.41 ± 1.22 to 118.11 ± 2.45 (mg NaOH/g; the saponification number ranged from 193.74 ±21.88 to 199.62 ± 12.63 (mg KOH/g; and the peroxide number ranged from 24.37 ± 2.44 to 26.07± 4.88 (mgek/kg, respectively. Oils was analyzed used GC-MS. The chemical components of ricebran oil are oleic acid (46.24%, palmitic acid (18.25%, linoleic acid (13.29%, 9-octadecane(7.76%.

  8. On-line detection of illicit substances in liquid phase with proton-transfer-reaction mass spectrometry (PTR-MS)

    Energy Technology Data Exchange (ETDEWEB)

    Juerschik, Simone; Agarwal, Bishu; Petersson, Fredrik [Institut fuer Ionenphysik und Angewandte Physik, Universitaet Innsbruck, Technikerstr. 25, 6020 Innsbruck (Austria); Sulzer, Philipp; Haidacher, Stefan; Jordan, Alfons; Schottkowsky, Ralf; Hartungen, Eugen; Hanel, Gernot; Seehauser, Hans; Maerk, Lukas [IONICON Analytik GmbH, Eduard-Bodem-Gasse 3, 6020 Innsbruck (Austria); Maerk, Tilmann D. [Institut fuer Ionenphysik und Angewandte Physik, Universitaet Innsbruck, Technikerstr. 25, 6020 Innsbruck (Austria); IONICON Analytik GmbH, Eduard-Bodem-Gasse 3, 6020 Innsbruck (Austria)

    2011-07-01

    The direct aqueous injection (DAI) technique was recently utilized for the detection of illicit substances in liquid phase. DAI turns out to be an ideal solution for direct analysis of liquid samples, since we can make good use of the outstanding advantages, such as real-time analysis, no sample preparation, low detection limits and short response time. Differences in TNT concentration in the water could be seen dependent on time and original size of the pieces and we could demonstrate a linear correlation between the concentration in liquid and the PTR-MS signal. Furthermore, we were also able to demonstrate that this method is capable of detecting minute traces of ''rape drugs'', i.e. {gamma}-butyrolactone and 1,4-butanediol, in liquids. This new method achieving sensitivities in the around 100 pptw range appears therefore well suited for the fight against drug crime and terrorism and for the evaluation of contamination of ammunition dumping sites.

  9. A novel liquid chromatography/tandem mass spectrometry (LC-MS/MS) based bioanalytical method for quantification of ethyl esters of Eicosapentaenoic acid (EPA) and Docosahexaenoic acid (DHA) and its application in pharmacokinetic study.

    Science.gov (United States)

    Viswanathan, Sekarbabu; Verma, P R P; Ganesan, Muniyandithevar; Manivannan, Jeganathan

    2017-07-15

    Omega-3 fatty acids are clinically useful and the two marine omega-3 fatty acids eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) are prevalent in fish and fish oils. Omega-3 fatty acid formulations should undergo a rigorous regulatory step in order to obtain United States Food and Drug Administration (USFDA) approval as prescription drug. In connection with that, despite quantifying EPA and DHA fatty acids, there is a need for quantifying the level of ethyl esters of them in biological samples. In this study, we make use of reverse phase high performance liquid chromatography coupled with mass spectrometry (RP-HPLC-MS)technique for the method development. Here, we have developed a novel multiple reaction monitoring method along with optimized parameters for quantification of EPA and DHA as ethyl esters. Additionally, we attempted to validate the bio-analytical method by conducting the sensitivity, selectivity, precision accuracy batch, carryover test and matrix stability experiments. Furthermore, we also implemented our validated method for evaluation of pharmacokinetics of omega fatty acid ethyl ester formulations. Copyright © 2017 Elsevier B.V. All rights reserved.

  10. Ultra high performance supercritical fluid chromatography coupled with tandem mass spectrometry for screening of doping agents. I: Investigation of mobile phase and MS conditions.

    Science.gov (United States)

    Nováková, Lucie; Grand-Guillaume Perrenoud, Alexandre; Nicoli, Raul; Saugy, Martial; Veuthey, Jean-Luc; Guillarme, Davy

    2015-01-01

    The conditions for the analysis of selected doping substances by UHPSFC-MS/MS were optimized to ensure suitable peak shapes and maximized MS responses. A representative mixture of 31 acidic and basic doping agents was analyzed, in both ESI+ and ESI- modes. The best compromise for all compounds in terms of MS sensitivity and chromatographic performance was obtained when adding 2% water and 10mM ammonium formate in the CO2/MeOH mobile phase. Beside mobile phase, the nature of the make-up solvent added for interfacing UHPSFC with MS was also evaluated. Ethanol was found to be the best candidate as it was able to compensate for the negative effect of 2% water addition in ESI- mode and provided a suitable MS response for all doping agents. Sensitivity of the optimized UHPSFC-MS/MS method was finally assessed and compared to the results obtained in conventional UHPLC-MS/MS. Sensitivity was improved by 5-100-fold in UHPSFC-MS/MS vs. UHPLC-MS/MS for 56% of compounds, while only one compound (bumetanide) offered a significantly higher MS response (4-fold) under UHPLC-MS/MS conditions. In the second paper of this series, the optimal conditions for UHPSFC-MS/MS analysis will be employed to screen >100 doping agents in urine matrix and results will be compared to those obtained by conventional UHPLC-MS/MS. Copyright © 2014 Elsevier B.V. All rights reserved.

  11. The potential of using laser ablation inductively coupled plasma time of flight mass spectrometry (LA-ICP-TOF-MS) in the forensic analysis of micro debris.

    Science.gov (United States)

    Scadding, Cameron J; Watling, R John; Thomas, Allen G

    2005-08-15

    The majority of crimes result in the generation of some form of physical evidence, which is available for collection by crime scene investigators or police. However, this debris is often limited in amount as modern criminals become more aware of its potential value to forensic scientists. The requirement to obtain robust evidence from increasingly smaller sized samples has required refinement and modification of old analytical techniques and the development of new ones. This paper describes a new method for the analysis of oxy-acetylene debris, left behind at a crime scene, and the establishment of its co-provenance with single particles of equivalent debris found on the clothing of persons of interest (POI). The ability to rapidly determine and match the elemental distribution patterns of debris collected from crime scenes to those recovered from persons of interest is essential in ensuring successful prosecution. Traditionally, relatively large amounts of sample (up to several milligrams) have been required to obtain a reliable elemental fingerprint of this type of material [R.J. Walting , B.F. Lynch, D. Herring, J. Anal. At. Spectrom. 12 (1997) 195]. However, this quantity of material is unlikely to be recovered from a POI. This paper describes the development and application of laser ablation inductively coupled plasma time of flight mass spectrometry (LA-ICP-TOF-MS), as an analytical protocol, which can be applied more appropriately to the analysis of micro-debris than conventional quadrupole based mass spectrometry. The resulting data, for debris as small as 70mum in diameter, was unambiguously matched between a single spherule recovered from a POI and a spherule recovered from the scene of crime, in an analytical procedure taking less than 5min.

  12. Determination of Metal Levels in Shamma (Smokeless Tobacco) with Inductively Coupled Plasma Mass Spectrometry (ICP-MS) in Najran, Saudi Arabia

    Science.gov (United States)

    Brima, Eid Ibrahim

    2016-10-01

    Objective: The use of Shamma (smokeless tobacco) by certain groups is giving rise to health problems, including cancer, in parts of Saudi Arabia. Our objective was to determine metals levels in Shamma using inductively coupled plasma mass spectrometry (ICP-MS). Methods: Thirty-three samples of Shamma (smokeless tobacco) were collected, comprising four types: brown Shamma (n = 14.0), red Shamma (n = 9.0), white Shamma (n = 4.0), and yellow Shamma (n = 6.0). All samples were collected randomly from Shamma users in the city of Najran. Levels of 11 elements (Al, As, Cd, Co, Cr, Cu, Li, Mn, Ni, Pb, and Zn) were determined by ICP-MS. Results: A mixed standard (20 ppb) of all elements was used for quality control, and average recoveries ranged from 74.7% to 112.2%. The highest average concentrations were found in the following order: Al (598.8–812.2 μg/g), Mn (51.0–80.6 μg/g), and Ni (23.2–53.3 μg/g) in all four Shamma types. The lowest concentrations were for As (0.7–1.0 μg/g) and Cd (0.0–0.06 μg/g). Conclusions: The colour of each Shamma type reflects additives mixed into the tobacco. Cr and Cu were showed significant differences (P awareness about the safety and health effects of Shamma, which is clearly a source of oral exposure to metals. Creative Commons Attribution License

  13. Liquid chromatography/negative electrospray ionization ion trap MS(2) mass spectrometry application for the determination of microcystins occurrence in Southern Portugal water reservoirs.

    Science.gov (United States)

    Rodrigues, M A; Reis, M P; Mateus, M C

    2013-11-01

    Microcystins (MCs) are toxins produced by cyanobacteria which are common organisms in the phytoplankton of eutrophic lakes, rivers and freshwater reservoirs. In the present work, a novel method of liquid chromatography-electrospray ion trap tandem mass spectrometry (LC/ESI/Ion trap-MS/MS), operated in the negative ionization mode, was developed for the analysis of these cyanotoxins. The method was applied to determine the amounts of total microcystins-LR, -YR and -RR in two water reservoirs in Southern Portugal, namely Alqueva and Beliche. A total of 30 water samples were analysed along 2011. Solid phase extraction (SPE) was used for sample cleaning-up and analyte enrichment. The extracted toxins were separated on a C18 column with a gradient of acetonitrile/water with 0.1% formic acid. Detection of microcystins was carried out using multiple reaction monitoring (MRM) in the negative polarity mode, as this method gave a higher selectivity. The MC-RR, YR and LR quantification limits were 17.9, 31.7 and 15.8 ng/L, respectively; quite below the limits recommended by WHO guidelines for drinking water (1 μg/L). Total MC highest concentrations were found in the warm months of June, July and September in Alqueva sampling sites, with concentrations of MC LR and RR ranging 17-344 and 25-212 ng/L, respectively, showing comparable results for MC-RR and LR and slightly lower concentration of MC-YR. Detected values for Beliche reservoir were below quantification limits. Copyright © 2013 Elsevier Ltd. All rights reserved.

  14. Determination of phosphatidylethanolamine molecular species in various food matrices by liquid chromatography-electrospray ionization-tandem mass spectrometry (LC-ESI-MS2).

    Science.gov (United States)

    Zhou, Li; Zhao, Minjie; Ennahar, Saïd; Bindler, Françoise; Marchioni, Eric

    2012-04-01

    A liquid chromatographic-electrospray ionization-tandem mass spectrometric (LC-ESI-MS(2)) method has been developed for determination of the molecular species of phosphatidylethanolamine (PE) in four food matrices (soy, egg yolk, ox liver, and krill oil). The extraction and purification method consisted of a pressurized liquid extraction procedure for total lipid (TL) extraction, purification of phospholipids (PLs) by adsorption on a silica gel column, and separation of PL classes by semi-preparative normal-phase HPLC. Separation and identification of PE molecular species were performed by reversed-phase HPLC coupled with electrospray ionization tandem mass spectrometry (ESI-MS(2)). Methanol containing 5 mmol L(-1) ammonium formate was used as the mobile phase. A variety of PE molecular species were detected in the four food matrices. (C16:0-C18:2)PE, (C18:2-C18:2)PE, and (C16:0-C18:1)PE were the major PE molecular species in soy. Egg yolk PE contained (C16:0-C18:1)PE, (C18:0-C18:1)PE, (C18:0-C18:2)PE, and (C16:0-C18:2)PE as the major molecular species. Ox liver PE was rich in the species (C18:0-C18:1)PE, (C18:0-C20:4)PE, and (C18:0-C18:2)PE. Finally, krill oil which was particularly rich in (C16:0(alkyl)-C22:6(acyl))plasmanylethanolamine (PakE), (C16:0-C22:6)PE, and (C16:0-C20:5)PE, seemed to be an interesting potential source for supplementation of food with eicosapentaenoic acid and docosahexaenoic acid.

  15. Spéciation de l'arsenic dans les produits de la pêche par couplage HPLC-ICP-MS après extraction assistée par micro-ondes (MAE). Contribution à l'évaluation des risques par l'estimation de sa bioaccessibilité

    OpenAIRE

    Dufailly , Vincent

    2008-01-01

    The government agencies generally evaluate the food risks related to the presence of arsenic in seafood samples by analyzing only total arsenic, without considering the various involved forms nor their bioavailability. The main objective of this study was to develop and validate a method allowing the French Food Safety Agency (AFSSA) to propose with its supervisions a better evaluation of the risks incurred by the consumer by determining the speciation and the bioaccessibility of the various ...

  16. Spéciation de l’arsenic dans les produits de la pêche par couplage HPLC/ICP-MS. Estimation de sa bioaccessibilité en ligne et applications à d'autres éléments traces métalliques d'intérêt

    OpenAIRE

    Leufroy , Axelle

    2012-01-01

    Arsenic is an element present in all compartments of the environment, and seafood constitutes a major source of exposure to arsenic through human consumption. Although there is currently no legislation on arsenic in food in France, government agencies generally assess the safety of food items based solely on the total concentration of the element, without taking into account its different species or their bioaccessibility. Therefore, the development of speciation analysis methods is particula...

  17. Quantification of 11-Carboxy-Delta-9-Tetrahydrocannabinol (THC-COOH) in Meconium Using Gas Chromatography/Mass Spectrometry (GC/MS).

    Science.gov (United States)

    Peat, Judy; Davis, Brehon; Frazee, Clint; Garg, Uttam

    2016-01-01

    Maternal substance abuse is an ongoing concern and detecting drug use during pregnancy is an important component of neonatal care when drug abuse is suspected. Meconium is the preferred specimen for drug testing because it is easier to collect than neonatal urine and it provides a much broader time frame of drug exposure. We describe a method for quantifying 11-carboxy-delta-9-tetrahydrocannabinol (THC-COOH) in meconium. After adding a labeled internal standard (THC-COOH D9) and acetonitrile, samples are sonicated to release both free and conjugated THC-COOH. The acetonitrile/aqueous layer is removed and mixed with a strong base to hydrolyze the conjugated THC-COOH. The samples are then extracted with an organic solvent mixture as part of a sample "cleanup." The organic solvent layer is discarded and the remaining aqueous sample is acidified. Following extraction with a second organic mixture, the organic layer is removed and concentrated to dryness. The resulting residue is converted to a trimethylsilyl (TMS) derivative and analyzed using gas chromatography/mass spectrometry (GC/MS) in selective ion monitoring (SIM) mode.

  18. Determination of chromium, iron and selenium in foodstuffs of animal origin by collision cell technology, inductively coupled plasma mass spectrometry (ICP-MS), after closed vessel microwave digestion

    International Nuclear Information System (INIS)

    Dufailly, Vincent; Noel, Laurent; Guerin, Thierry

    2006-01-01

    The determination of chromium ( 52 Cr), iron ( 56 Fe) and selenium ( 80 Se) isotopes in foodstuffs of animal origin has been performed by collision cell technology (CCT) mode using an inductively coupled plasma mass spectrometry (ICP-MS) as detector after closed vessel microwave digestion. To significantly decrease the argon-based interferences at mass to charge ratios (m/z): 52 ( 40 Ar 12 C), 56 ( 40 Ar 16 O) and 80 ( 40 Ar 40 Ar), the gas-flow rates of a helium and hydrogen mixture used in the hexapole collision cell were optimised to 1.5 ml min -1 H 2 and 0.5 ml min -1 He and the quadrupole bias was adjusted daily between -2 and -15 mV. Limits of quantification (LOQ) of 0.025, 0.086 and 0.041 mg kg -1 for Cr, Fe and Se, respectively, in 6% HNO 3 were estimated under optimized CCT conditions. These LOQ were improved by a factor of approximately 10 for each element compared to standard mode. Precision under repeatability, intermediate precision reproducibility and trueness have been tested on nine different certified reference materials in foodstuffs of animal origin and on an external proficiency testing scheme. The results obtained for chromium, iron and selenium were in all cases in good agreement with the certified values and trueness was improved, compared to those obtained in standard mode

  19. Determination of the alkylpyrazine composition of coffee using stable isotope dilution-gas chromatography-mass spectrometry (SIDA-GC-MS).

    Science.gov (United States)

    Pickard, Stephanie; Becker, Irina; Merz, Karl-Heinz; Richling, Elke

    2013-07-03

    A stable isotope dilution analysis based on gas chromatography-mass spectrometry analysis (SIDA-GC-MS) was developed for the quantitative analysis of 12 alkylpyrazines found in commercially available coffee samples. These compounds contribute to coffee flavor. The accuracy of this method was tested by analyzing model mixtures of alkylpyrazines. Comparisons of alkylpyrazine-concentrations suggested that water as extraction solvent was superior to dichloromethane. The distribution patterns of alkylpyrazines in different roasted coffees were quite similar. The most abundant alkylpyrazine in each coffee sample was 2-methylpyrazine, followed by 2,6-dimethylpyrazine, 2,5-dimethylpyrazine, 2-ethylpyrazine, 2-ethyl-6-methylpyrazine, 2-ethyl-5-methylpyrazine, and 2,3,5-trimethylpyrazine, respectively. Among the alkylpyrazines tested, 2,3-dimethylpyrazine, 2-ethyl-3-methylpyrazine, 2-ethyl-3,6-dimethylpyrazine, and 2-ethyl-3,5-dimethylpyrazine revealed the lowest concentrations in roasted coffee. By the use of isotope dilution analysis, the total concentrations of alkylpyrazines in commercially available ground coffee ranged between 82.1 and 211.6 mg/kg, respectively. Decaffeinated coffee samples were found to contain lower amounts of alkylpyrazines than regular coffee samples by a factor of 0.3-0.7, which might be a result of the decaffeination procedure.

  20. Use of Electro-spray Ionization Mass Spectrometry (ESI-MS) for the characterization of complexes 'ligand - metallic cations' in solution

    Energy Technology Data Exchange (ETDEWEB)

    Berthon, Laurence; Zorz, Nicole; Lagrave, Stephanie; Gannaz, Benoit; Hill, Clement [CEA-Marcoule DEN-DRCP-SCPS-LCSE, BP 17171, 30207 Bagnols sur Ceze cedex (France)

    2008-07-01

    In the framework of nuclear waste reprocessing, separation processes of minor actinides from fission products are developed by Cea. In order to understand the mechanisms involved in the extraction processes, the 'ligand/metallic cation' complexes, formed in the organic phases are characterized by electro-spray-mass-spectrometry (ESI-MS). This paper deals with the extraction of lanthanides (III) and americium (III) cations by an organic phase composed of a malonamide or / and a dialkyl phosphoric acid, diluted in an aliphatic diluent. For the dialkyl phosphoric acid, Ln(DEHP){sub 3}(HDEHP){sub 3} complexes are observed and in the presence of a large excess of Ln(NO{sub 3}){sub 3}, dinuclear species are also observed. For the malonamide extractant, it appears that the complexes formed in the organic phase are of the Nd(NO{sub 3}){sub 3}D{sub x} type, with 2 {<=} x {<=} 4: their distributions depend on the ratio [Ln]/[DMDOHEMA]. When the two extractants are present in the organic phase, mixed 'Ln-malonamide-dialkyl phosphoric acid' species are observed. The influence of several parameters, such as extractant concentration, solute concentration, aqueous acidity and the nature of the cations (lanthanides or americium) are studied. (authors)

  1. Identification of volatile butyl rubber thermal-oxidative degradation products by cryofocusing gas chromatography/mass spectrometry (cryo-GC/MS).

    Energy Technology Data Exchange (ETDEWEB)

    Smith, Jonell Nicole; White, Michael Irvin; Bernstein, Robert; Hochrein, James Michael

    2013-02-01

    Chemical structure and physical properties of materials, such as polymers, can be altered as aging progresses, which may result in a material that is ineffective for its envisioned intent. Butyl rubber formulations, starting material, and additives were aged under thermal-oxidative conditions for up to 413 total days at up to 124 ÀC. Samples included: two formulations developed at Kansas City Plant (KCP) (#6 and #10), one commercially available formulation (#21), Laxness bromobutyl 2030 starting material, and two additives (polyethylene AC-617 and Vanax MBM). The low-molecular weight volatile thermal-oxidative degradation products that collected in the headspace over the samples were preconcentrated, separated, and detected using cryofocusing gas chromatography mass spectrometry (cryo-GC/MS). The majority of identified degradation species were alkanes, alkenes, alcohols, ketones, and aldehydes. Observations for Butyl #10 aged in an oxygen-18 enriched atmosphere (18O2) were used to verify when the source of oxygen in the applicable degradation products was from the gaseous environment rather than the polymeric mixture. For comparison purposes, Butyl #10 was also aged under non-oxidative thermal conditions using an argon atmosphere.

  2. Investigation of natural phosphatidylcholine sources: separation and identification by liquid chromatography-electrospray ionization-tandem mass spectrometry (LC-ESI-MS2) of molecular species.

    Science.gov (United States)

    Le Grandois, Julie; Marchioni, Eric; Zhao, Minjie; Giuffrida, Francesca; Ennahar, Saïd; Bindler, Françoise

    2009-07-22

    This study is a contribution to the exploration of natural phospholipid (PL) sources rich in long-chain polyunsaturated fatty acids (LC-PUFAs) with nutritional interest. Phosphatidylcholines (PCs) were purified from total lipid extracts of different food matrices, and their molecular species were separated and identified by liquid chromatography-electrospray ionization-tandem mass spectrometry (LC-ESI-MS(2)). Fragmentation of lithiated adducts allowed for the identification of fatty acids linked to the glycerol backbone. Soy PC was particularly rich in species containing essential fatty acids, such as (18:2-18:2)PC (34.0%), (16:0-18:2)PC (20.8%), and (18:1-18:2)PC (16.3%). PC from animal sources (ox liver and egg yolk) contained major molecular species, such as (16:0-18:2)PC, (16:0-18:1)PC, (18:0-18:2)PC, or (18:0-18:1)PC. Finally, marine source (krill oil), which was particularly rich in (16:0-20:5)PC and (16:0-22:6)PC, appeared to be an interesting potential source for food supplementation with LC-PUFA-PLs, particularly eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA).

  3. Analytical detection of explosives and illicit, prescribed and designer drugs using proton transfer reaction time-of-flight mass spectrometry (PTR-TOF-MS)

    Energy Technology Data Exchange (ETDEWEB)

    Agarwal, Bishu; Petersson, Fredrik; Juerschik, Simone [Institut fuer Ionenphysik und Angewandte Physik, Universitaet Innsbruck, Technikerstr. 25, 6020 Innsbruck (Austria); Sulzer, Philipp; Jordan, Alfons [IONICON Analytik GmbH, Eduard-Bodem-Gasse 3, 6020 Innsbruck (Austria); Maerk, Tilmann D. [Institut fuer Ionenphysik und Angewandte Physik, Universitaet Innsbruck, Technikerstr. 25, 6020 Innsbruck (Austria); IONICON Analytik GmbH, Eduard-Bodem-Gasse 3, 6020 Innsbruck (Austria); Watts, Peter; Mayhew, Chris A. [School of Physics and Astronomy, University of Birmingham, Edgbaston, Birmingham B15 4TT (United Kingdom)

    2011-07-01

    This work demonstrates the extremely favorable features of Proton Transfer Reaction Time-of-flight Mass Spectrometry (PTR-TOF-MS) for the detection and identification of solid explosives, chemical warfare agent simulants and illicit, prescribed and designer drugs in real time. Here, we report the use of PTR-TOF, for the detection of explosives (e.g., trinitrotoluene, trinitrobenzene) and illicit, prescribed and designer drugs (e.g., ecstasy, morphine, heroin, ethcathinone, 2C-D). For all substances, the protonated parent ion (as we used H{sub 3}O{sup +} as a reagent ion) could be detected, providing a high level of confidence in their identification since the high mass resolution allows compounds having the same nominal mass to be separated. We varied the E/N from 90 to 220 T{sub d} (1 T{sub d}=10{sup -17} Vcm{sup -1}). This allowed us to study fragmentation pathways as a function of E/N (reduced electric field). For a few compounds rather unusual E/N dependencies were also discovered.

  4. Improved resolution of hydrocarbon structures and constitutional isomers in complex mixtures using Gas Chromatography-Vacuum Ultraviolet-Mass Spectrometry (GC-VUV-MS)

    Energy Technology Data Exchange (ETDEWEB)

    Aerosol Dynamics Inc; Aerodyne Research, Inc.,; Tofwerk AG, Thun; Isaacman, Gabriel; Wilson, Kevin R.; Chan, Arthur W. H.; Worton, David R.; Kimmel, Joel R.; Nah, Theodora; Hohaus, Thorsten; Gonin, Marc; Kroll, Jesse H.; Worsnop, Doug R.; Goldstein, Allen H.

    2011-09-13

    Understanding the composition of complex hydrocarbon mixtures is important for environmental studies in a variety of fields, but many prevalent compounds cannot be confidently identified using traditional gas chromatography-mass spectrometry (GC-MS) techniques. This work uses vacuum-ultraviolet (VUV) ionization to elucidate the structures of a traditionally"unresolved complex mixture" by separating components by GC retention time, tR, and mass-to-charge ratio, m/Q, which are used to determine carbon number, NC, and the number of rings and double bonds, NDBE. Constitutional isomers are resolved based on tR, enabling the most complete quantitative analysis to date of structural isomers in an environmentally-relevant hydrocarbon mixture. Unknown compounds are classified in this work by carbon number, degree of saturation, presence of rings, and degree of branching, providing structural constraints. The capabilities of this analysis are explored using diesel fuel, in which constitutional isomer distribution patterns are shown to be reproducible between carbon numbers and follow predictable rules. Nearly half of the aliphatic hydrocarbon mass is shown to be branched, suggesting branching is more important in diesel fuel than previously shown. The classification of unknown hydrocarbons and the resolution of constitutional isomers significantly improves resolution capabilities for any complex hydrocarbon mixture.

  5. Multi-residue analysis method for analysis of pharmaceuticals using liquid chromatography-time of flight/mass spectrometry (LC-TOF/MS) in water sample

    Science.gov (United States)

    Al-Qaim, Fouad Fadhil; Abdullah, Md Pauzi; Othman, Mohamed Rozali

    2013-11-01

    In this work, a developed method using solid - phase extraction (SPE) followed by liquid chromatography - time of flight mass spectrometry (LC-ESI-TOF/MS) was developed and validated for quantification and confirmation of eleven pharmaceuticals with different therapeutic classes in water samples, Malaysia. These compounds are caffeine (CAF), prazosin (PRZ), enalapril (ENL), carbamazepine (CBZ), nifedipine (NFD), levonorgestrel (LNG), simvastatin (SMV), hydrochlorothiazide (HYD), gliclazide (GLIC), diclofenac-Na (DIC-Na) and mefenamic acid (MEF). LC was performed on a Dionex Ultimate 3000/LC 09115047 (USA) system. Chromatography was performed on a Thermo Scientific C18 (250 mm × 2.1 mm, i.d.: 5μm) column. Several parameters were optimised such as; mobile phase, gradient elution, collision energy and solvent elution for extraction of compounds from water. The recoveries obtained ranged from 30-148 % in river water. Five pharmaceutical compounds were detected in the surface water samples: caffeine, prazosin, enalpril, diclofenac-Na and mefenamic acid. The developed method is precise and accepted recoveries were got. In addition, this method is suitable to identify and quantify trace concentrations of pharmaceuticals in surface water.

  6. Analytical mass spectrometry

    Energy Technology Data Exchange (ETDEWEB)

    1990-01-01

    This 43rd Annual Summer Symposium on Analytical Chemistry was held July 24--27, 1990 at Oak Ridge, TN and contained sessions on the following topics: Fundamentals of Analytical Mass Spectrometry (MS), MS in the National Laboratories, Lasers and Fourier Transform Methods, Future of MS, New Ionization and LC/MS Methods, and an extra session. (WET)

  7. Analytical mass spectrometry. Abstracts

    Energy Technology Data Exchange (ETDEWEB)

    1990-12-31

    This 43rd Annual Summer Symposium on Analytical Chemistry was held July 24--27, 1990 at Oak Ridge, TN and contained sessions on the following topics: Fundamentals of Analytical Mass Spectrometry (MS), MS in the National Laboratories, Lasers and Fourier Transform Methods, Future of MS, New Ionization and LC/MS Methods, and an extra session. (WET)

  8. A liquid chromatography-tandem mass spectrometry (LC-MS/MS) method for the human biomonitoring of non-occupational exposure to the fragrance 2-(4-tert-butylbenzyl)propionaldehyde (lysmeral).

    Science.gov (United States)

    Pluym, Nikola; Krnac, Dusan; Gilch, Gerhard; Scherer, Max; Leibold, Edgar; Scherer, Gerhard

    2016-08-01

    2-(4-tert-Butylbenzyl)propionaldehyde also known as lysmeral, lilial, or lily aldehyde (CAS No. 80-54-6) is a synthetic odorant mainly used as a fragrance in a variety of consumer products like cleaning agents, fine fragrances, cosmetics, and air fresheners. Due to its broad application in various fields, lysmeral was selected for the development of a biomonitoring method for the quantitative exposure assessment within the frame of the cooperation project of the Federal Ministry for the Environment, Nature Conservation, Building and Nuclear Safety (BMUB) and the German Chemical Industry Association (VCI). A method based on ultra-high pressure liquid chromatography combined with tandem mass spectrometry (UPLC-MS/MS) was developed for the simultaneous determination of potential biomarkers of lysmeral in human urine samples. Sample cleanup was performed by liquid-liquid extraction (LLE). Quantification was achieved by standard addition using stable isotope-labeled, authentic reference standards. The method is characterized by its robustness, reliability, and excellent sensitivity as proven during method validation according to approved standard guidelines. The following five lysmeral metabolites were identified as potential biomarkers of exposure for lysmeral in human urine samples: lysmerol, lysmerylic acid, hydroxylated lysmerylic acid, tert-butylbenzoic acid (TBBA), and tert-butylhippuric acid (TBHA). The determination of lysmerol required derivatization with 3-nitrophthalic acid anhydride and showed the lowest limit of detection (LOD) and limit of quantification (LOQ) in urine (0.035 and 0.10 μg/L, respectively). LOD and LOQ for the other metabolites were in the range of 0.12-0.15 and 0.36-0.45 μg/L, respectively. Accuracy for all analytes was in the range of 90-110 %. Intra- and inter-day precision was in the range of 5-10 %, except for TBHA, for which the coefficient of variation was unacceptably high (>20 %) and therefore excluded from the method. The

  9. Independent assessment of matrix-assisted laser desorption/ionization mass spectrometry (MALDI-MS) sample preparation quality: Effect of sample preparation on MALDI-MS of synthetic polymers.

    Science.gov (United States)

    Kooijman, Pieter C; Kok, Sander; Honing, Maarten

    2017-02-28

    Matrix-assisted laser desorption/ionization mass spectrometry (MALDI-MS) provides detailed and in-depth information about the molecular characteristics of synthetic polymers. To obtain the most accurate results the sample preparation parameters should be chosen to suit the sample and the aim of the experiment. Because the underlying principles of MALDI are still not fully known, a priori determination of optimal sample preparation protocols is often not possible. Employing an automated sample preparation quality assessment method recently presented by us we quantified the sample preparation quality obtained using various sample preparation protocols. Six conventional matrices with and without added potassium as a cationization agent and six ionic liquid matrices (ILMs) were assessed using poly(ethylene glycol) (PEG), polytetrahydrofuran (PTHF) and poly(methyl methacrylate) (PMMA) as samples. All sample preparation protocols were scored and ranked based on predefined quality parameters and spot-to-spot repeatability. Clearly distinctive preferences were observed in matrix identity and cationization agent for PEG, PTHF and PMMA, as the addition of an excess of potassium cationization agent results in an increased score for PMMA and a contrasting matrix-dependent effect for PTHF and PEG. The addition of excess cationization agent to sample mixtures dissipates any overrepresentation of high molecular weight polymer species. Our results show reduced ionization efficiency and similar sample deposit homogeneity for all tested ILMs, compared with well-performing conventional MALDI matrices. The results published here represent a start in the unsupervised quantification of sample preparation quality for MALDI samples. This method can select the best sample preparation parameters for any synthetic polymer sample and the results can be used to formulate hypotheses on MALDI principles. Copyright © 2016 John Wiley & Sons, Ltd. Copyright © 2016 John Wiley & Sons, Ltd.

  10. Enhancement of sensitivity in the determination of organic trace compounds in complex matrices with liquid chromatography-mass spectrometry (LC-MS)

    International Nuclear Information System (INIS)

    Mascher, D.G.

    2002-05-01

    The PhD-thesis deals with 'enhancement of sensitivity in the determination of organic trace compounds in complex matrices with liquid chromatography-mass spectrometry (LC-MS)'. Almost the most important factor is the enhancement of the ionization yield with Atmospheric Pressure Chemical Ionization (APCI) or Electrospray Ionization (ESI) in LC-MS. Ionization yields of different compounds can vary by a factor of 10000. Three ways to solve this problem of little ionization yield were tried: 1) Modification of the mobile phase in HPLC 2) Chemical modification of the analytes 3) A new type of ionization called Atmospheric Pressure Photo Ionization (APPI). ad 1) By using specific additives to mobile phases ion suppression that might derive from an ion pair reagent that was necessary for chromatography could be omitted. General remarks cannot be done. ad 2) Chemical modification or so called derivatization is well known for UV- and fluorescence-detection for a long period of time. As substances containing nitrogene (e.g. primary, secondary or tertiary amines) often have good ionization yields, poor or relatively poor ionizable substances like carboxylic acids, sugars and partially phenolic steroids were used as analytes for derivatization reactions. By using Dansyl as Dansylchlorid or Dansylhydrazine a basic derivatization agent could be found that ionizes very well. A 200 times more sensitive determination of estrogenes is possible after derivatization with Dansylchlorid. Using a tandem-mass-spectrometer a lower limit of quantification of 2 pg/mL plasma could be reached by using 1 mL of plasma. For ketones like carvon and campher an enhancement by a factor of 500 and 4000 could be reached by using Dansylhydrazine as the derivatization agent. For fatty acids DMEQ as derivatization agent enhanced the sensitivity by a factor of 20 to 100. ad 3) APPI as a new ionization mode showed really good results for specific molecules. Relatively unpolar substances as diphenylsulfide

  11. Analysis of factors affecting volatile compound formation in roasted pumpkin seeds with selected ion flow tube-mass spectrometry (SIFT-MS) and sensory analysis.

    Science.gov (United States)

    Bowman, T; Barringer, S

    2012-01-01

    Pumpkin (Cucurbita pepo and maxima) seeds are uniquely flavored and commonly consumed as a healthy roasted snack. The objective was to determine dominant volatiles in raw and roasted pumpkin seeds, and the effect of seed coat, moisture content, fatty acid ratio, total lipids, reducing sugars, and harvest year on volatile formation. Sensory was conducted to evaluate overall liking of seed variety and texture. Seed processing included extraction from the fruit, dehydration, and roasting (150 °C). Oil extraction was done using soxhlet, fatty acid profile using Gas Chromatography Flame Ionization Detector, and reducing sugars using 3,5-dinitrosalicylic acid and UV-spectroscopy. Headspace analysis of seeds was performed by selected ion flow tube-mass spectrometry (SIFT-MS). Volatiles dominating in raw pumpkin seeds were lipid aldehydes, ethyl acetate, 2,3-butandione, and dimethylsulfide. Compounds contributing to roasted aroma include alkylpyrazines and Strecker and lipid aldehydes. Overall, hull-less seeds had higher volatile lipid aldehydes and Strecker aldehydes. Seeds dehydrated to a moisture content of 6.5% before roasting had higher initial and final volatile concentrations than seeds starting at 50% moisture. Higher oil content resulted in higher lipid aldehyde formation during roasting with a moderate correlation between free fatty acid ratio and corresponding lipid aldehyde. Harvest year (2009 compared with 2010) had a significant impact on volatile formation in hull-less seeds, but not as much as variety differences. No significant correlation was found between reducing sugars and volatile formation. Sensory showed that hull-less seeds were liked significantly more than hulled seeds. Elucidation of aromatic flavor development during roasting with SIFT-MS provides information on flavor release and offers better control during processing. Knowledge of volatiles in raw and roasted pumpkin seeds and effects of seed coat, moisture content, seed composition, and

  12. Assessment of four protocols for rapid bacterial identification from positive blood culture pellets by matrix-assisted laser desorption ionization-time of flight mass spectrometry (Vitek® MS).

    Science.gov (United States)

    Thomin, Jean; Aubin, Guillaume Ghislain; Foubert, Fabrice; Corvec, Stéphane

    2015-08-01

    In this study, we developed and compared four protocols to prepare a bacterial pellet from 944 positive blood cultures for direct MALDI-TOF mass spectrometry Vitek® MS analysis. Protocol 4, tested on 200 monomicrobial samples, allowed 83% of bacterial identification. This easy, fast, cheap and accurate method is promising in daily practice, especially to limit broad range antibiotic treatment. Copyright © 2015 Elsevier B.V. All rights reserved.

  13. Determination of chromium, iron and selenium in foodstuffs of animal origin by collision cell technology, inductively coupled plasma mass spectrometry (ICP-MS), after closed vessel microwave digestion

    Energy Technology Data Exchange (ETDEWEB)

    Dufailly, Vincent [Agence Francaise de Securite Sanitaire des Aliments - Laboratoire d' Etudes et de Recherches sur la Qualite des Aliments et des procedees agroalimentaires - Unite des Contaminants Inorganiques et Mineraux de l' Environnement, 23, avenue du General de Gaulle, F-94706 Maisons-Alfort Cedex (France); Noel, Laurent [Agence Francaise de Securite Sanitaire des Aliments - Laboratoire d' Etudes et de Recherches sur la Qualite des Aliments et des procedees agroalimentaires - Unite des Contaminants Inorganiques et Mineraux de l' Environnement, 23, avenue du General de Gaulle, F-94706 Maisons-Alfort Cedex (France); Guerin, Thierry [Agence Francaise de Securite Sanitaire des Aliments - Laboratoire d' Etudes et de Recherches sur la Qualite des Aliments et des procedees agroalimentaires - Unite des Contaminants Inorganiques et Mineraux de l' Environnement, 23, avenue du General de Gaulle, F-94706 Maisons-Alfort Cedex (France)]. E-mail: t.guerin@afssa.fr

    2006-04-21

    The determination of chromium ({sup 52}Cr), iron ({sup 56}Fe) and selenium ({sup 80}Se) isotopes in foodstuffs of animal origin has been performed by collision cell technology (CCT) mode using an inductively coupled plasma mass spectrometry (ICP-MS) as detector after closed vessel microwave digestion. To significantly decrease the argon-based interferences at mass to charge ratios (m/z): 52 ({sup 40}Ar{sup 12}C), 56 ({sup 40}Ar{sup 16}O) and 80 ({sup 40}Ar{sup 40}Ar), the gas-flow rates of a helium and hydrogen mixture used in the hexapole collision cell were optimised to 1.5 ml min{sup -1} H{sub 2} and 0.5 ml min{sup -1} He and the quadrupole bias was adjusted daily between -2 and -15 mV. Limits of quantification (LOQ) of 0.025, 0.086 and 0.041 mg kg{sup -1} for Cr, Fe and Se, respectively, in 6% HNO{sub 3} were estimated under optimized CCT conditions. These LOQ were improved by a factor of approximately 10 for each element compared to standard mode. Precision under repeatability, intermediate precision reproducibility and trueness have been tested on nine different certified reference materials in foodstuffs of animal origin and on an external proficiency testing scheme. The results obtained for chromium, iron and selenium were in all cases in good agreement with the certified values and trueness was improved, compared to those obtained in standard mode.

  14. Multi-element analysis of urine using dynamic reaction cell inductively coupled plasma mass spectrometry (ICP-DRC-MS — A practical application

    Directory of Open Access Journals (Sweden)

    Renata Brodzka

    2013-04-01

    Full Text Available Objectives: The method for the determination of As, Al, Cd, Ni, Pb (toxic elements and Cr, Co, Cu, Fe, Mn, Zn (essential elements in human urine by the use of Inductively Coupled Plasma Mass Spectrometry (quadrupole ICP-MS DRCe Elan, Perkin Elmer with the dynamic reaction cell (DRC was developed. Materials and Methods: The method has been applied for multi-element analysis of the urine of 16 non-exposed healthy volunteers and 27 workers employed in a copper smelter. The analysis was conducted after initial 10-fold dilution of the urine samples with 0,1% nitric acid. Rhodium was used as an internal standard. The method validation parameters such as detection limit, sensitivity, precision were described for all elements. Accuracy of the method was checked by the regular use of certified reference materials ClinCheck®-Control Urine (Recipe as well as by participation of the laboratory in the German External Quality Assessment Scheme (G-EQUAS. Results: The detection limits (DL 3s of the applied method were 0.025, 0.007, 0.002, 0.004, 0.004, 0.086, 0.037, 0.009, 0.016, 0.008, 0.064 (μg/l for Al, As, Cd, Cr, Co, Cu, Fe, Mn, Ni, Pb, Zn in urine, respectively. For each element linearity with correlation coefficient of at least 0.999 was determined. Spectral interferences from some of the ions were removed using DRC-e with addition of alternative gas: methane for cobalt, copper, cadmium, chromium, iron, manganese, nickel and rhodium, and oxygen for arsenic. Conclusions: The developed method allows to determine simultaneously eleven elements in the urine with low detection limits, high sensitivity and good accuracy. Moreover, the method is appropriate for the assessment of both environmental and occupational exposure.

  15. Pediatric MS

    Science.gov (United States)

    ... Pediatric MS Share this page Facebook Twitter Email Pediatric MS Pediatric MS Pediatric MS Support Pediatric Providers ... system through the Pediatric MS Support Group . Treating pediatric MS In 2018 the U.S. Food and Drug ...

  16. Real-time analysis of ambient organic aerosols using aerosol flowing atmospheric-pressure afterglow mass spectrometry (AeroFAPA-MS)

    Science.gov (United States)

    Brüggemann, Martin; Karu, Einar; Stelzer, Torsten; Hoffmann, Thorsten

    2015-04-01

    Organic aerosol accounts for a major fraction of atmospheric aerosols and has implications on the earth's climate and human health. However, due to the chemical complexity its measurement remains a major challenge for analytical instrumentation.1 Here, we present the development, characterization and application of a new soft ionization technique that allows mass spectrometric real-time detection of organic compounds in ambient aerosols. The aerosol flowing atmospheric-pressure afterglow (AeroFAPA) ion source utilizes a helium glow discharge plasma to produce excited helium species and primary reagent ions. Ionization of the analytes occurs in the afterglow region after thermal desorption and results mainly in intact molecular ions, facilitating the interpretation of the acquired mass spectra. In the past, similar approaches were used to detect pesticides, explosives or illicit drugs on a variety of surfaces.2,3 In contrast, the AeroFAPA source operates 'online' and allows the detection of organic compounds in aerosols without a prior precipitation or sampling step. To our knowledge, this is the first application of an atmospheric-pressure glow discharge ionization technique to ambient aerosol samples. We illustrate that changes in aerosol composition and concentration are detected on the time scale of seconds and in the ng-m-3 range. Additionally, the successful application of AeroFAPA-MS during a field study in a mixed forest region in Central Europe is presented. Several oxidation products of monoterpenes were clearly identified using the possibility to perform tandem MS experiments. The acquired data are in agreement with previous studies and demonstrate that AeroFAPA-MS is a suitable tool for organic aerosol analysis. Furthermore, these results reveal the potential of this technique to enable new insights into aerosol formation, growth and transformation in the atmosphere. References: 1) IPCC, 2013: Summary for Policymakers. In: Climate Change 2013: The

  17. Fe- and Cu-complex formation with artificial ligands investigated by ultra-high resolution Fourier-transform ion cyclotron resonance mass spectrometry (FT-ICR-MS: Implications for natural metal-organic complex studies

    Directory of Open Access Journals (Sweden)

    Hannelore Waska

    2016-07-01

    Full Text Available In recent years, electrospray-ionization mass spectrometry (ESI-MS has been increasingly used to complement the bulk determination of metal-ligand equilibria, for example via competitive ligand exchange-adsorptive cathodic stripping voltammetry (CLE-ACSV. However, ESI-MS speciation analyses may be impacted by instrumental artefacts such as reduction reactions, fragmentation, and adduct formation at the ESI source, changes in the ionization efficiencies of the detected species in relation to sample matrix, and peak overlaps in response to increasing sample complexity. In our study, equilibria of the known artificial ligands citrate, ethylenediaminetetraacetic acid (EDTA, 1-nitroso-2-naphthol (NN, and salicylaldoxime (SA with iron (Fe and copper (Cu were investigated by ultra-high resolution ESI-MS, Fourier-transform ion cyclotron resonance mass spectrometry (FT-ICR-MS, under a variety of sample matrix and ionization settings. The acquired mass spectra were compared with metal-ligand equilibrium data from the literature as well as an adapted speciation model. Overall, the mass spectra produced representative species mentioned in previous reports and predicted by the speciation calculations, such as Fe(Cit, Cu(Cit2, Fe(EDTA, Cu(EDTA, Fe(NN3, and Cu(SA2. The analyses furthermore revealed new species which had been hypothesized but not measured directly using other methods, for example ternary complexes of citrate with Fe and Cu, Cu(SA monomers, and the dimer Fe(SA2. Finally, parallel measurements of a Cu+SA calibration series and a Cu+SA+EDTA competition series indicated that FT-ICR-MS can produce linear responses and low detection limits analogous to those of ACSV. We propose that ultra-high resolution FT-ICR-MS can be used as a representative tool to study interactions of trace metals with artificial as well as natural, unknown ligands at the molecular level.

  18. MALDI-TOF MS/MS measurements of PMMA

    NARCIS (Netherlands)

    Becer, C.R.; Baumgaertel, A.; Gottschaldt, M.; Schubert, U.S.

    2008-01-01

    The polymer poly(Me methacrylate) (PMMA) was analyzed using the matrix-assisted laser desorption ionization time-of-flight mass spectrometry (MALDI-TOF MS) technique. The MALDI-TOF MS app. was coupled with a collision-induced dissocn. (CID) unit. The performance of the MALDI-TOF/TOF MS method in

  19. A Collaborative Study: Determination of Mycotoxins in Corn, Peanut Butter, and Wheat Flour Using Stable Isotope Dilution Assay (SIDA) and Liquid Chromatography-Tandem Mass Spectrometry (LC-MS/MS).

    Science.gov (United States)

    Zhang, Kai; Schaab, Matthew R; Southwood, Gavin; Tor, Elizabeth R; Aston, Linda S; Song, Wenlu; Eitzer, Brian; Majumdar, Sanghamitra; Lapainis, Theodore; Mai, Huy; Tran, Kevin; El-Demerdash, Aref; Vega, Victor; Cai, Yanxuan; Wong, Jon W; Krynitsky, Alexandra J; Begley, Timothy H

    2017-08-23

    A collaborative study was conducted to evaluate stable isotope dilution assay (SIDA) and LC-MS/MS for the simultaneous determination of aflatoxins B 1 , B 2 , G 1 , and G 2 ; deoxynivalenol; fumonisins B 1 , B 2 , and B 3 ; ochratoxin A; HT-2 toxin; T-2 toxin; and zearalenone in foods. Samples were fortified with 12 13 C uniformly labeled mycotoxins ( 13 C-IS) corresponding to the native mycotoxins and extracted with acetonitrile/water (50:50 v/v), followed by centrifugation, filtration, and LC-MS/MS analysis. In addition to certified reference materials, the six participating laboratories analyzed corn, peanut butter, and wheat flour fortified with the 12 mycotoxins at concentrations ranging from 1.0 to 1000 ng/g. Using their available LC-MS/MS platform, each laboratory developed in-house instrumental conditions for analysis. The majority of recoveries ranged from 80 to 120% with relative standard derivations (RSDs) <20%. Greater than 90% of the average recoveries of the participating laboratories were in the range of 90-110%, with repeatability RSD r (within laboratory) < 10% and reproducibility RSD R (among laboratory) < 15%. All Z scores of the results of certified reference materials were between -2 and 2. Using 13 C-IS eliminated the need for matrix-matched calibration standards for quantitation, simplified sample preparation, and achieved simultaneous identification and quantitation of multiple mycotoxins in a simple LC-MS/MS procedure.

  20. Eddy covariance emission and deposition flux measurements using proton transfer reaction – time of flight – mass spectrometry (PTR-TOF-MS): comparison with PTR-MS measured vertical gradients and fluxes

    NARCIS (Netherlands)

    Park, J.H.; Goldstein, A.H.; Timkovsky, J|info:eu-repo/dai/nl/330541676; Fares, S.; Weber, R.; Karlik, J.; Holzinger, R.|info:eu-repo/dai/nl/337989338

    2013-01-01

    During summer 2010, a proton transfer reaction – time of flight – mass spectrometer (PTR-TOF-MS) and a quadrupole proton transfer reaction mass spectrometer (PTR-MS) were deployed simultaneously for one month in an orange orchard in the Central Valley of California to collect continuous data

  1. Comprehensive Two-Dimensional Hydrophilic Interaction Chromatography (HILIC) × Reversed-Phase Liquid Chromatography Coupled to High-Resolution Mass Spectrometry (RP-LC-UV-MS) Analysis of Anthocyanins and Derived Pigments in Red Wine.

    Science.gov (United States)

    Willemse, Chandré M; Stander, Maria A; Vestner, Jochen; Tredoux, Andreas G J; de Villiers, André

    2015-12-15

    Changes in anthocyanin chemistry represent some of the most important transformations involved in red wine aging. However, accurate analysis of the derived pigments, as required to study the evolution of anthocyanins and tannins during aging, is hampered by their extreme structural diversity, low levels, and the fact that many of these compounds have identical mass spectral characteristics. In this context, chromatographic separation is critical. In this contribution, the application of online hydrophilic interaction chromatography (HILIC) × reversed-phase liquid chromatography (RP-LC) separation coupled to high-resolution mass spectrometry (MS) is described for the detailed characterization of anthocyanins and their derived pigments in aged red wine. A systematic approach was followed for the optimization of HILIC × RP-LC separation parameters using a capillary liquid chromatography (LC) system in the first dimension and an ultrahigh-pressure LC system in the second dimension to ensure maximum sensitivity and performance. Ninety four (94) anthocyanin-derived pigments were tentatively identified in one- and six-year-old Pinotage wines using accurate mass and fragmentation information obtained using quadrupole-time-of-flight mass spectrometry (Q-TOF-MS). Online HILIC × RP-LC-MS was found to offer high-resolution separation, because of the combination of two different separation modes, while the structured elution order observed improved the certainty in compound identification. Therefore, this approach shows promise for the detailed elucidation of the chemical alteration of anthocyanins during wine aging.

  2. Determination of vitamins D2 and D3 in selected food matrices by online high-performance liquid chromatography-gas chromatography-mass spectrometry (HPLC-GC-MS).

    Science.gov (United States)

    Nestola, Marco; Thellmann, Andrea

    2015-01-01

    An online normal-phase liquid chromatography-gas chromatography-mass spectrometry (HPLC-GC-MS) method was developed for the determination of vitamins D2 and D3 in selected food matrices. Transfer of the sample from HPLC to GC was realized by large volume on-column injection; detection was performed with a time-of-flight mass spectrometer (TOF-MS). Typical GC problems in the determination of vitamin D such as sample degradation or sensitivity issues, previously reported in the literature, were not observed. Determination of total vitamin D content was done by quantitation of its pyro isomer based on an isotopically labelled internal standard (ISTD). Extracted ion traces of analyte and ISTD showed cross-contribution, but non-linearity of the calibration curve was not determined inside the chosen calibration range by selection of appropriate quantifier ions. Absolute limits of detection (LOD) and quantitation (LOQ) for vitamins D2 and D3 were calculated as approximately 50 and 150 pg, respectively. Repeatability with internal standard correction was below 2 %. Good agreement between quantitative results of an established high-performance liquid chromatography with UV detection (HPLC-UV) method and HPLC-GC-MS was found. Sterol-enriched margarine was subjected to HPLC-GC-MS and HPLC-MS/MS for comparison, because HPLC-UV showed strong matrix interferences. HPLC-GC-MS produced comparable results with less manual sample cleanup. In summary, online hyphenation of HPLC and GC allowed a minimization in manual sample preparation with an increase of sample throughput.

  3. In search of ancient biomarkers: Using femtosecond - Laser Desorption Post Ionization - Mass Spectrometry (fs-LDPI-MS) to map organic compounds within ca. 2.7 Ga samples from the Abitibi greenstone belt, Ontario, Canada

    Science.gov (United States)

    Pasterski, M. J.; Barry, G.; Hanley, L.; Kenig, F. P. H.

    2016-12-01

    One of the major challenges within the field of organic geochemistry is to determine whether an observed biomarker signature was emplaced during sedimentation (indigenous), after sedimentation via the post-depositional migration of fluids (non-indigenous), or during sampling, storage, or analysis (contaminant). Current geochemical techniques (e.g. gas chromatography-mass spectrometry, GC-MS and GCxGC-MS) can effectively determine the composition and structure of the organic constituents of a sample. However, because of the multiple preparatory steps necessary prior to GC-MS analysis (sample crushing, solvent extraction, organic fraction separation) it is impossible to precisely determine the spatial relationship between the host sample and the organic molecules within. We used an MS imaging method developed by Prof. Luke Hanley at the University of Illinois at Chicago, femtosecond-laser desorption post ionization-MS (fs-LDPI-MS), to map the organics within previously characterized ca.2.7 billion year old (Ga) metasediments from the Abitibi greenstone belt near Timmins, ON, Canada. We then compared the MS images to petrographic observations that displayed the distribution of mineral species with well constrained mineralization ages as well as fluid inclusions within the samples. Fluid inclusions are formed during mineralization and have the ability to remain intact over long timescales (up to billions of years), protecting the fluids inside from the introduction of non-indigenous and contaminant biomarkers. Although migrating post-depositional fluids can remineralize sediments, fluid inclusions associated with secondary additions are focused along grain boundaries and microfractures (secondary inclusions), thus, inclusions which are located within grain boundaries can be considered primary and the age of their formation can be determined relative to the host rock. Preliminary results indicate that previously observed biomarkers may be linked to a series of

  4. Development and validation of a method for the analysis of Ochratoxin A in roasted coffee by liquid chromatography/electrospray-mass spectrometry in Tandem (LC/ESI-MS/MS

    Directory of Open Access Journals (Sweden)

    Raquel D. C. C. Bandeira

    2012-01-01

    Full Text Available A method using LC/ESI-MS/MS for the quantitative analysis of Ochratoxin A in roasted coffee was described. Linearity was demonstrated (r = 0.9175. The limits of detection and quantification were 1.0 and 3.0 ng g-1, respectively. Trueness, repeatability and intermediate precision values were 89.0-108.8%; 2.4-13.7%; 12.5-17.8%, respectively. To the best of our knowledge, this is the first report in which Ochratoxin A in roasted coffee is analysed by LC/ESI-MS/MS, contributing to the field of mycotoxin analysis, and it will be used for future production of Certified Reference Material.

  5. EPA Method 8321B (SW-846): Solvent-Extractable Nonvolatile Compounds by High Performance Liquid Chromatography-Thermospray-Mass Spectrometry (HPLC-TS-MS) or Ultraviolet (UV) Detection

    Science.gov (United States)

    Method 8321B describes procedures for preparation and analysis of solid, aqueous liquid, drinking water and wipe samples using high performance liquid chromatography and mass spectrometry for extractable non-volatile compounds.

  6. LC-MS (/MS) in clinical toxicology screening methods.

    Science.gov (United States)

    Viette, Véronique; Hochstrasser, Denis; Fathi, Marc

    2012-01-01

    Toxicological screening is the analysis of biological samples to detect and identify unknown compounds. The high selectivity and sensitivity of liquid chromatography (LC) coupled to mass spectrometry (MS) or tandem mass spectrometry (MS/MS) technology provide an attractive alternative to the current methods (LC-UV, GC/MS, etc.). For these reasons, an increasing number of applications are being published. This paper is a brief overview of LC-MS(/MS) screening methods developed for clinical toxicology in recent years. Various sample treatments, chromatographic separations and detection by mass spectrometry can be combined to obtain screening methods adapted to the constraints and needs of clinical toxicology laboratories. Currently the techniques are in the hands of specialists, mainly in academic institutions. However, the evolution in technology should allow application of these techniques as a tool in toxicology laboratories, thus allowing a more widespread exploitation of their potential.

  7. Measurement of elemental speciation by liquid chromatography -- inductively coupled plasma mass spectrometry (LC-ICP-MS) with the direct injection nebulizer (DIN)

    Energy Technology Data Exchange (ETDEWEB)

    Shum, Sam [Iowa State Univ., Ames, IA (United States)

    1993-05-01

    This thesis is divided into 4 parts: elemental speciation, speciation of mercury and lead compounds by microbore column LC-ICP-MS with direct injection nebulization, spatially resolved measurements of size and velocity distributions of aerosol droplets from a direct injection nebulizer, and elemental speciation by anion exchange and size exclusion chromatography with detection by ICP-MS with direct injection nebulization.

  8. Development of analytical methods for the determination of trace elements in sediment with Neutron ActivAtion method (NAA) and Inductively Coupled Plasma Mass Spectrometry (ICP-MS)

    International Nuclear Information System (INIS)

    Nam, Sang Ho; Kim, Jae Jin; Chung, Yong Sam; Kim, Sun Ha

    2005-01-01

    The analytical methods for the determination of major elements (Al, Ca, K, Fe, Mg) in sediment have been investigated with ICP-MS. The analytical results of major elements with Cool ICP-MS were much better than those with normal ICP-MS. The analytical results were compared with those of NAA. NAA were a little superior to ICP-MS for the determination of major elements in sediment, and NAA is a non-destructive analytical method. The analytical methods for the determination of minor elements (Cr, Ce, U, Co, Pb, As, Se) in sediment have been also studied with ICP-MS. The analytical results by standard calibration with ICP-MS were not accurate due to matrix interferences. Thus, internal standard method was applied, then the analytical results for minor element with ICP-MS were greatly improved. The analytical results obtained by ICP-MS were compared with those obtained by NAA. It showed that the two analytical methods have great capabilities for the determination of minor elements in sediments

  9. Principal component analysis of normalized full spectrum mass spectrometry data in multiMS-toolbox: An effective tool to identify important factors for classification of different metabolic patterns and bacterial strains.

    Science.gov (United States)

    Cejnar, Pavel; Kuckova, Stepanka; Prochazka, Ales; Karamonova, Ludmila; Svobodova, Barbora

    2018-06-15

    Explorative statistical analysis of mass spectrometry data is still a time-consuming step. We analyzed critical factors for application of principal component analysis (PCA) in mass spectrometry and focused on two whole spectrum based normalization techniques and their application in the analysis of registered peak data and, in comparison, in full spectrum data analysis. We used this technique to identify different metabolic patterns in the bacterial culture of Cronobacter sakazakii, an important foodborne pathogen. Two software utilities, the ms-alone, a python-based utility for mass spectrometry data preprocessing and peak extraction, and the multiMS-toolbox, an R software tool for advanced peak registration and detailed explorative statistical analysis, were implemented. The bacterial culture of Cronobacter sakazakii was cultivated on Enterobacter sakazakii Isolation Agar, Blood Agar Base and Tryptone Soya Agar for 24 h and 48 h and applied by the smear method on an Autoflex speed MALDI-TOF mass spectrometer. For three tested cultivation media only two different metabolic patterns of Cronobacter sakazakii were identified using PCA applied on data normalized by two different normalization techniques. Results from matched peak data and subsequent detailed full spectrum analysis identified only two different metabolic patterns - a cultivation on Enterobacter sakazakii Isolation Agar showed significant differences to the cultivation on the other two tested media. The metabolic patterns for all tested cultivation media also proved the dependence on cultivation time. Both whole spectrum based normalization techniques together with the full spectrum PCA allow identification of important discriminative factors in experiments with several variable condition factors avoiding any problems with improper identification of peaks or emphasis on bellow threshold peak data. The amounts of processed data remain still manageable. Both implemented software utilities are available

  10. Combined use of liquid chromatography-hybrid quadrupole time-of-flight mass spectrometry (LC-QTOF-MS) and high performance liquid chromatography with photodiode array detector (HPLC-DAD) in systematic toxicological analysis.

    Science.gov (United States)

    Broecker, Sebastian; Pragst, Fritz; Bakdash, Abdulsallam; Herre, Sieglinde; Tsokos, Michael

    2011-10-10

    Time of flight mass spectrometry provides new possibilities of substance identification by determination of the molecular formula from accurate molecular mass and isotope pattern. However, the huge number of possible isomers requires additional evidence. As a suitable way for routine performance of systematic toxicological analysis, a method for combined use of liquid chromatography-hybrid quadrupole time-of-flight mass spectrometry (LC-QTOF-MS) and high performance liquid chromatography with diode array detector (HPLC-DAD) was developed and applied to blood samples from 77 death cases. The blood samples were prepared by extraction with CH(2)Cl(2) and by protein precipitation with acetonitrile (1:4 (v/v)). The evaporated extracts were reconstituted in 35% acetonitril/0.1% formic acid/H(2)O and aliquots were injected for analysis by LC-QTOF-MS (Agilent 6530) and HPLC-DAD (Agilent 1200). A valve switching system enabled simultaneous operation of both separated chromatographic lines under their respective optimal conditions using the same autosampler. The ESI-QTOF-MS instrument was run in data dependent acquisition mode with switching between MS and MS/MS (cycle time 1.1s) and measuring the full mass spectra and the collision induced dissociation (CID) fragment spectra of all essential [M+H](+) ions. Libraries of accurate mass CID spectra (~2500 substances) and of DAD-UV spectra (~3300 substances) of the authors were used for substance identification. The application of this procedure is demonstrated in detail at four examples with multiple drug intake or administration. In the 77 cases altogether 198 substances were identified (87 by DAD and 195 by QTOF-MS) with a frequency between 1 and 20. In practical application, the sample preparation proved to be suitable for both techniques and for a wide variety of substances with different polarity. The automatic performance of the measurements was efficient and robust. Mutual confirmation, decrease of false positive and

  11. Proteome-based bacterial identification using matrix-assisted laser desorption ionization-time of flight mass spectrometry (MALDI-TOF MS): A revolutionary shift in clinical diagnostic microbiology.

    Science.gov (United States)

    Nomura, Fumio

    2015-06-01

    Rapid and accurate identification of microorganisms, a prerequisite for appropriate patient care and infection control, is a critical function of any clinical microbiology laboratory. Matrix-assisted laser desorption ionization-time of flight mass spectrometry (MALDI-TOF MS) is a quick and reliable method for identification of microorganisms, including bacteria, yeast, molds, and mycobacteria. Indeed, there has been a revolutionary shift in clinical diagnostic microbiology. In the present review, the state of the art and advantages of MALDI-TOF MS-based bacterial identification are described. The potential of this innovative technology for use in strain typing and detection of antibiotic resistance is also discussed. This article is part of a Special Issue entitled: Medical Proteomics. Copyright © 2014 Elsevier B.V. All rights reserved.

  12. Evaluation of repetitive-PCR and matrix-assisted laser desorption ionization-time of flight mass spectrometry (MALDI-TOF MS for rapid strain typing of Bacillus coagulans.

    Directory of Open Access Journals (Sweden)

    Jun Sato

    Full Text Available In order to establish rapid and accurate typing method for Bacillus coagulans strains which is important for controlling in some canned foods and tea-based beverages manufacturing because of the high-heat resistance of the spores and high tolerance of the vegetative cells to catechins and chemicals, matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS and repetitive-PCR (rep-PCR were evaluated. For this purpose, 28 strains of B. coagulans obtained from various culture collections were tested. DNA sequence analyses of the genes encoding 16S rRNA and DNA gyrase classified the test strains into two and three groups, respectively, regardless of their phenotypes. Both MALDI-TOF MS and rep-PCR methods classified the test strains in great detail. Strains classified in each group showed similar phenotypes, such as carbohydrate utilization determined using API 50CH. In particular, the respective two pairs of strains which showed the same metabolic characteristic were classified into the same group by both MALDI-TOF MS and rep-PCR methods separating from the other strains. On the other hand, the other strains which have the different profiles of carbohydrate utilization were separated into different groups by these methods. These results suggested that the combination of MALDI-TOF MS and rep-PCR analyses was advantageous for the rapid and detailed typing of bacterial strains in respect to both phenotype and genotype.

  13. Evaluation of repetitive-PCR and matrix-assisted laser desorption ionization-time of flight mass spectrometry (MALDI-TOF MS) for rapid strain typing of Bacillus coagulans.

    Science.gov (United States)

    Sato, Jun; Nakayama, Motokazu; Tomita, Ayumi; Sonoda, Takumi; Hasumi, Motomitsu; Miyamoto, Takahisa

    2017-01-01

    In order to establish rapid and accurate typing method for Bacillus coagulans strains which is important for controlling in some canned foods and tea-based beverages manufacturing because of the high-heat resistance of the spores and high tolerance of the vegetative cells to catechins and chemicals, matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) and repetitive-PCR (rep-PCR) were evaluated. For this purpose, 28 strains of B. coagulans obtained from various culture collections were tested. DNA sequence analyses of the genes encoding 16S rRNA and DNA gyrase classified the test strains into two and three groups, respectively, regardless of their phenotypes. Both MALDI-TOF MS and rep-PCR methods classified the test strains in great detail. Strains classified in each group showed similar phenotypes, such as carbohydrate utilization determined using API 50CH. In particular, the respective two pairs of strains which showed the same metabolic characteristic were classified into the same group by both MALDI-TOF MS and rep-PCR methods separating from the other strains. On the other hand, the other strains which have the different profiles of carbohydrate utilization were separated into different groups by these methods. These results suggested that the combination of MALDI-TOF MS and rep-PCR analyses was advantageous for the rapid and detailed typing of bacterial strains in respect to both phenotype and genotype.

  14. Matrix-assisted Laser Desorption Ionization-Time-of-Flight Mass Spectrometry (MALDI-TOF MS) as a Reliable Tool to Identify Species of Catalase-negative Gram-positive Cocci not Belonging to the Streptococcus Genus.

    Science.gov (United States)

    Almuzara, Marisa; Barberis, Claudia; Velázquez, Viviana Rojas; Ramirez, Maria Soledad; Famiglietti, Angela; Vay, Carlos

    2016-01-01

    To evaluate the performance of matrix-assisted laser desorption ionization-time-of-flight mass spectrometry (MALDI-TOF MS) by using 190 Catalase-negative Gram-Positive Cocci (GPC) clinical isolates. All isolates were identified by conventional phenotypic tests following the proposed scheme by Ruoff and Christensen and MALDI-TOF MS (Bruker Daltonics, BD, Bremen, Germany). Two different extraction methods (direct transfer formic acid method on spot and ethanol formic acid extraction method) and different cut-offs for genus/specie level identification were used. The score cut-offs recommended by the manufacturer (≥ 2.000 for species-level, 1.700 to 1.999 for genus level and genus level, ≥ 1.700 for species-level and score genus or species. MALDI-TOF MS identification was considered correct when the result obtained from MS database agreed with the phenotypic identification result. When both methods gave discordant results, the 16S rDNA or sodA genes sequencing was considered as the gold standard identification method. The results obtained by MS concordant with genes sequencing, although discordant with conventional phenotyping, were considered correct. MS results discordant with 16S or sod A identification were considered incorrect. Using the score cut-offs recommended by the manufacturer, 97.37% and 81.05% were correctly identified to genus and species level, respectively. On the other hand, using lower cut-off scores for identification, 97.89% and 94.21% isolates were correctly identified to genus and species level respectively by MALDI-TOF MS and no significant differences between the results obtained with two extraction methods were obtained. The results obtained suggest that MALDI-TOF MS has the potential of being an accurate tool for Catalase-negative GPC identification even for those species with difficult diagnosis as Helcococcus , Abiotrophia , Granulicatella , among others. Nevertheless, expansion of the library, especially including more strains with

  15. Identification of Sarin and Related Compounds in Snow by Packed Capillary Liquid Chromatography-Electrospray Mass Spectrometry (LC-ESI-MS)

    National Research Council Canada - National Science Library

    D'Agostino, Paul

    2001-01-01

    Packed capillary LC-ESl-MS was used for the analysis of a snow sample that was accidentally contaminated with an organophosphorus chemical warfare agent during the destruction of a chemical munition...

  16. Reduction of measurement uncertainty by experimental design in high-order (double, triple, and quadruple) isotope dilution mass spectrometry: application to GC-MS measurement of bromide.

    Science.gov (United States)

    Pagliano, Enea; Mester, Zoltán; Meija, Juris

    2013-03-01

    Since its introduction a century ago, isotope dilution analysis has played a central role in developments of analytical chemistry. This method has witnessed many elaborations and developments over the years. To date, we have single, double, and even triple isotope dilution methods. In this manuscript, we summarize the conceptual aspects of isotope dilution methods and introduce the quadruple dilution and the concept of exact matching triple and quadruple dilutions. The comparison of isotope dilution methods is performed by determination of bromide ions in groundwater using novel ethyl-derivatization chemistry in conjunction with GC/MS. We show that the benefits of higher-order isotope dilution methods are countered with a greater need for careful experimental design of the isotopic blends. Just as for ID(2)MS, ID(3)MS and ID(4)MS perform best when the isotope ratio of one sample/spike blend is matched with that of a standard/spike blend (exact matching).

  17. Determination and identification of hydrophilic and hydrophobic arsenic species in methanol extract of fresh cod liver by RP-HPLC with simultaneous ICP-MS and ESI-Q-TOF-MS detection.

    Science.gov (United States)

    Arroyo-Abad, Uriel; Lischka, Susanne; Piechotta, Christian; Mattusch, Jürgen; Reemtsma, Thorsten

    2013-12-01

    The present study was focused on the determination and identification of arsenic species in methanolic extracts of cod liver. Arsenic species were fractionated and the fractions analysed by RP-HPLC-ICP-MS coupled with ESI-Q-TOF-MS. The total concentration of arsenic in the fresh cod liver was analysed by ICP-MS to be 1.53±0.02 mg As kg(-1)w.w. and the extraction recovery was ca. 100% and the column recovery >93%. Besides polar inorganic and methylated arsenic species (>70%) more hydrophobic arsenic-containing fatty acids and hydrocarbons occurred. Based on the mass spectrometric data proposals for molecular structures were elaborated for 20 of the organic As species included 10 arsenic-containing fatty acids (AsFA) and an arsenic-containing hydrocarbon (AsHC) mentioned for the first time in fresh cod liver. Arsenobetaine was found as main water-soluble arsenic compound in cod liver followed by higher molecular mass arsenic-containing fatty acids and hydrocarbons. Copyright © 2013 Elsevier Ltd. All rights reserved.

  18. Development of realtime monitoring technology for laser photoreaction product - Development of glow discharge-mass spectrometry (GD-MS) hybrid techniques for trace analysis of refractory elements

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Sang Chun [Kyungnam University, Masan (Korea); Kim, Ha Suck [Seoul National University, Seoul (Korea); Kim, Hyo Jin [Dongduk Women' s University, Seoul (Korea)

    2000-04-01

    This research is focusing on development of hybrid techniques of glow discharge-mass spectrometry for the trace analysis of refractory elements. At first, we developed a glow discharge(GD) ionization cell and its characteristics was investigated. The new GD cell was designed based on direct current hollow cathode glow discharge and it is used for quadrupole mass analyzer and time-of-flight mass analyzer. Currently, GD-quadrupole mass spectrometry is working for the analysis of refractory elements. The experimental results show relatively good for trace analysis. In addition, ion mobile spectrometry using plasma and liquid discharge technique were investigated for the analysis of refractory elements and both techniques need more investigation to deduce the their usefulness. 30 refs., 67 figs., 4 tabs. (Author)

  19. Assessing direct analysis in real-time-mass spectrometry (DART-MS) for the rapid identification of additives in food packaging.

    Science.gov (United States)

    Ackerman, L K; Noonan, G O; Begley, T H

    2009-12-01

    The ambient ionization technique direct analysis in real time (DART) was characterized and evaluated for the screening of food packaging for the presence of packaging additives using a benchtop mass spectrometer (MS). Approximate optimum conditions were determined for 13 common food-packaging additives, including plasticizers, anti-oxidants, colorants, grease-proofers, and ultraviolet light stabilizers. Method sensitivity and linearity were evaluated using solutions and characterized polymer samples. Additionally, the response of a model additive (di-ethyl-hexyl-phthalate) was examined across a range of sample positions, DART, and MS conditions (temperature, voltage and helium flow). Under optimal conditions, molecular ion (M+H+) was the major ion for most additives. Additive responses were highly sensitive to sample and DART source orientation, as well as to DART flow rates, temperatures, and MS inlet voltages, respectively. DART-MS response was neither consistently linear nor quantitative in this setting, and sensitivity varied by additive. All additives studied were rapidly identified in multiple food-packaging materials by DART-MS/MS, suggesting this technique can be used to screen food packaging rapidly. However, method sensitivity and quantitation requires further study and improvement.

  20. Mass spectrometry. [review of techniques

    Science.gov (United States)

    Burlingame, A. L.; Kimble, B. J.; Derrick, P. J.

    1976-01-01

    Advances in mass spectrometry (MS) and its applications over the past decade are reviewed in depth, with annotated literature references. New instrumentation and techniques surveyed include: modulated-beam MS, chromatographic MS on-line computer techniques, digital computer-compatible quadrupole MS, selected ion monitoring (mass fragmentography), and computer-aided management of MS data and interpretation. Areas of application surveyed include: organic MS and electron impact MS, field ionization kinetics, appearance potentials, translational energy release, studies of metastable species, photoionization, calculations of molecular orbitals, chemical kinetics, field desorption MS, high pressure MS, ion cyclotron resonance, biochemistry, medical/clinical chemistry, pharmacology, and environmental chemistry and pollution studies.

  1. Application of matrix-assisted laser desorption/ionization mass spectrometry imaging in combination with LC-MS in pharmacokinetic study of metformin

    Czech Academy of Sciences Publication Activity Database

    Strnad, Štěpán; Vrkoslav, Vladimír; Klimšová, Z.; Zemenová, J.; Cvačka, Josef; Maletínská, Lenka; Sýkora, D.

    2018-01-01

    Roč. 10, č. 2 (2018), s. 71-81 ISSN 1757-6180 Institutional support: RVO:61388963 Keywords : dried blood spots * mass spectrometry imaging * metformin Subject RIV: CB - Analytical Chemistry, Separation OBOR OECD: Analytical chemistry Impact factor: 2.673, year: 2016

  2. Characterization of non-polar aromatic hydrocarbons in crude oil using atmospheric pressure laser ionization and Fourier transform ion cyclotron resonance mass spectrometry (APLI FT-ICR MS).

    Science.gov (United States)

    Schrader, Wolfgang; Panda, Saroj K; Brockmann, Klaus J; Benter, Thorsten

    2008-07-01

    We report on the successful application of the recently introduced atmospheric pressure laser ionization (APLI) method as a novel tool for the analysis of crude oil and its components. Using Fourier transform ion cyclotron resonance mass spectrometry, unambiguous determination of key compounds in this complex matrix with unprecedented sensitivity is presented.

  3. Dispersal kinetics of deuterated water in the lungs and airways following mouth inhalation: real-time breath analysis by flowing afterglow mass spectrometry (FA-MS)

    Czech Academy of Sciences Publication Activity Database

    Tan, B. K.; Smith, D.; Španěl, Patrik; Davies, S. J.

    2010-01-01

    Roč. 4, č. 1 (2010), 017109 ISSN 1752-7155 Institutional research plan: CEZ:AV0Z40400503 Keywords : mass spectrometry * breath analysis * pulmonary-edema Subject RIV: CF - Physical ; Theoretical Chemistry Impact factor: 1.828, year: 2010

  4. NMR/MS Translator for the Enhanced Simultaneous Analysis of Metabolomics Mixtures by NMR Spectroscopy and Mass Spectrometry: Application to Human Urine.

    Science.gov (United States)

    Bingol, Kerem; Brüschweiler, Rafael

    2015-06-05

    A novel metabolite identification strategy is presented for the combined NMR/MS analysis of complex metabolite mixtures. The approach first identifies metabolite candidates from 1D or 2D NMR spectra by NMR database query, which is followed by the determination of the masses (m/z) of their possible ions, adducts, fragments, and characteristic isotope distributions. The expected m/z ratios are then compared with the MS(1) spectrum for the direct assignment of those signals of the mass spectrum that contain information about the same metabolites as the NMR spectra. In this way, the mass spectrum can be assigned with very high confidence, and it provides at the same time validation of the NMR-derived metabolites. The method was first demonstrated on a model mixture, and it was then applied to human urine collected from a pool of healthy individuals. A number of metabolites could be detected that had not been reported previously, further extending the list of known urine metabolites. The new analysis approach, which is termed NMR/MS Translator, is fully automated and takes only a few seconds on a computer workstation. NMR/MS Translator synergistically uses the power of NMR and MS, enhancing the accuracy and efficiency of the identification of those metabolites compiled in databases.

  5. Improved methods for urinary atrazine mercapturate analysis-Assessment of an enzyme-linked immunosorbent assay (ELISA) and a novel liquid chromatography-mass spectrometry (LC-MS) method utilizing online solid phase extraction (SPE)

    International Nuclear Information System (INIS)

    Koivunen, Marja E.; Dettmer, Katja; Vermeulen, Roel; Bakke, Berit; Gee, Shirley J.; Hammock, Bruce D.

    2006-01-01

    Elimination of interfering substances in urine by solid phase extraction (SPE) prior to analysis resulted in 10-fold improvement in the sensitivity of atrazine mercapturate (AM) enzyme-linked immunosorbent assay (ELISA) compared to previous reports. Of the two tested SPE systems, Oasis[reg] HLB and MCX, the mixed-mode MCX gave good recoveries (82%) of AM in spiked samples measured by ELISA, whereas the reverse-phase HLB phase was not compatible with the immunochemical method. At relatively high concentrations of urinary AM (>20 ng mL -1 ), sample dilution was effective enough for the elimination of interfering substances. The new liquid chromatography-mass spectrometry (LC-MS) method developed for AM utilizes online-SPE with Oasis[reg] HLB, column switching and a stable-isotope internal standard. The limit of quantification (0.05 ng mL -1 ) indicates improved sensitivity compared with most previously published LC-MS methods for AM. Validation of all three methods, LC-MS, ELISA + SPE and ELISA + dilution with spiked urine samples showed good correlation between the known and measured concentrations with R 2 values of 0.996, 0.957 and 0.961, respectively. When a set (n = 70 plus 12 blind duplicates) of urine samples from farmers exposed to atrazine was analyzed, there was a good agreement (R 2 = 0.917) between the log normalized data obtained by ELISA + SPE and LC-MS. High correlation among the data obtained by the two tested methods and the LC-MS method by the Center of Disease Control and Prevention (CDC), together with low variability among the blind duplicates, suggests that both methods reported here would be suitable for the analysis of urinary AM as a biomarker for human exposure of atrazine

  6. Analytical capabilities of high performance liquid chromatography - Atmospheric pressure photoionization - Orbitrap mass spectrometry (HPLC-APPI-Orbitrap-MS) for the trace determination of novel and emerging flame retardants in fish.

    Science.gov (United States)

    Zacs, D; Bartkevics, V

    2015-10-22

    A new analytical method was established and validated for the analysis of 27 brominated flame retardants (BFRs), including so called "emerging" and "novel" BFRs (EBFRs and NBFRs) in fish samples. High performance liquid chromatography (HPLC) coupled to Orbitrap mass spectrometry (Orbitrap-MS) employing atmospheric pressure photoionization (APPI) interface operated in negative mode was used for the identification/quantitation of contaminants. HPLC-Orbitrap-MS analysis provided a fast separation of selected analytes within 14 min, thus demonstrating a high throughput processing of samples. The developed methodology was tested by intralaboratory validation in terms of recovery, repeatability, linear calibration ranges, instrumental and method limits of quantitation (i-LOQ and m-LOQ), and where possible, trueness was verified by analysis of certified reference materials (CRMs). Recoveries of analytes were between 80 and 119%, while the repeatability in terms of relative standard deviations (RSDs) was in the range from 1.2 to 15.5%. The measured values for both analyzed CRMs agreed with the provided consensus values, revealing the recovery of reference concentrations in 72-119% range. The elaborated method met the sensitivity criterion according to Commission Recommendation 2014/118/EU on monitoring of BFRs in food products for majority of the compounds. The concentrations of polybrominated diphenyl ethers (PBDEs) in real samples determined by HPLC-APPI-Orbitrap-MS method and validated gas chromatography-high-resolution mass spectrometry (GC-HRMS) method were found to be in a good agreement. Copyright © 2015 Elsevier B.V. All rights reserved.

  7. Evaluation of MALDI-TOF MS (Matrix-Assisted Laser Desorption-Ionization Time-of-Flight Mass Spectrometry) for routine identification of anaerobic bacteria.

    Science.gov (United States)

    Rodríguez-Sánchez, Belén; Alcalá, Luis; Marín, Mercedes; Ruiz, Adrián; Alonso, Elena; Bouza, Emilio

    2016-12-01

    Information regarding the use of MALDI-TOF MS as an alternative to conventional laboratory methods for the rapid and reliable identification of bacterial isolates is still limited. In this study, MALDI-TOF MS was evaluated on 295 anaerobic isolates previously identified by 16S rRNA gene sequencing and with biochemical tests (Rapid ID 32A system, BioMérieux). In total, 85.8% of the isolates were identified by MALDI-TOF MS at the species level vs 49.8% using the Rapid ID 32A system (p anaerobic isolates in the microbiology laboratory. Its implementation will reduce the turnaround time for a final identification and the number of isolates that require 16S rRNA sequencing. Copyright © 2016 Elsevier Ltd. All rights reserved.

  8. Rapid qualitative analysis of 2 flavonoids, rutin and silybin, in medical pills by direct analysis in real-time mass spectrometry (DART-MS) combined with in situ derivatization.

    Science.gov (United States)

    Nagy, Tibor; Kuki, Ákos; Nagy, Lajos; Zsuga, Miklós; Kéki, Sándor

    2018-03-01

    Direct analysis in real-time mass spectrometry (DART-MS) with in situ silylation was used for the rapid analysis of the flavonoids silybin ((2R,3R)-3,5,7-trihydroxy-2-[3-(4-hydroxy-3-methoxyphenyl)-2-hydroxymethyl-2,3-dihydrobenzo[1,4]dioxin-6-yl]chroman-4-one) and rutin (quercetin-3-O-rutinoside). Three different derivatization reagents, hexamethyldisilazane/trimethylchlorosilane/pyridine (HMDS/TMCS/pyridine), N,O-bis(trimethylsilyl)acetamide/trimethylchlorosilane/N-trimethylsilyimidazole (BSA/TMCS/TMSI), and N,O-bis(trimethylsilyl)trifluoroacetamide/trimethylchlorosilane (BSTFA/TMCS), were applied. Silybin and rutin were detected with various degrees of silylation, and the formation of dimers with pyridine and imidazole was also observed. HMDS/TMCS/pyridine was the best choice for the DART-MS analysis of silybin, and BSA/TMCS/TMSI was the most effective for the detection of rutin. The effects of the DART source temperature on desorption, ionization, in-source fragmentation, dimer formation, and hydrolysis of the trimethylsilyl groups were also studied. In addition, the collision-induced dissociation properties of the derivatized silybin and rutin were explored. With our in situ silylation method, the derivatized bioactive compounds in intact medical pills could also be detected by DART-MS. Copyright © 2017 John Wiley & Sons, Ltd.

  9. Fourier Transform Infrared (FT-IR) and Laser Ablation Inductively Coupled Plasma-Mass Spectrometry (LA-ICP-MS) Imaging of Cerebral Ischemia: Combined Analysis of Rat Brain Thin Cuts Toward Improved Tissue Classification.

    Science.gov (United States)

    Balbekova, Anna; Lohninger, Hans; van Tilborg, Geralda A F; Dijkhuizen, Rick M; Bonta, Maximilian; Limbeck, Andreas; Lendl, Bernhard; Al-Saad, Khalid A; Ali, Mohamed; Celikic, Minja; Ofner, Johannes

    2018-02-01

    Microspectroscopic techniques are widely used to complement histological studies. Due to recent developments in the field of chemical imaging, combined chemical analysis has become attractive. This technique facilitates a deepened analysis compared to single techniques or side-by-side analysis. In this study, rat brains harvested one week after induction of photothrombotic stroke were investigated. Adjacent thin cuts from rats' brains were imaged using Fourier transform infrared (FT-IR) microspectroscopy and laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS). The LA-ICP-MS data were normalized using an internal standard (a thin gold layer). The acquired hyperspectral data cubes were fused and subjected to multivariate analysis. Brain regions affected by stroke as well as unaffected gray and white matter were identified and classified using a model based on either partial least squares discriminant analysis (PLS-DA) or random decision forest (RDF) algorithms. The RDF algorithm demonstrated the best results for classification. Improved classification was observed in the case of fused data in comparison to individual data sets (either FT-IR or LA-ICP-MS). Variable importance analysis demonstrated that both molecular and elemental content contribute to the improved RDF classification. Univariate spectral analysis identified biochemical properties of the assigned tissue types. Classification of multisensor hyperspectral data sets using an RDF algorithm allows access to a novel and in-depth understanding of biochemical processes and solid chemical allocation of different brain regions.

  10. Microorganisms in cryopreserved semen and culture media used in the in vitro production (IVP) of bovine embryos identified by matrix-assisted laser desorption ionization mass spectrometry (MALDI-MS).

    Science.gov (United States)

    Zampieri, Dávila; Santos, Vanessa G; Braga, Patrícia A C; Ferreira, Christina R; Ballottin, Daniela; Tasic, Ljubica; Basso, Andréa C; Sanches, Bruno V; Pontes, José H F; da Silva, Bárbara Pereira; Garboggini, Fabiana Fantinatti; Eberlin, Marcos N; Tata, Alessandra

    2013-09-01

    Commercial cattle breeders produce their own herd offspring for the dairy and beef market using artificial insemination. The procedure involves sanitary risks associated with the collection and commercialization of the germplasm, and the in vitro production and transfer of the bovine embryos must be monitored by strict health surveillance. To avoid the spreading of infectious diseases, one must rely on using controlled and monitored germplasm, media, and reagents that are guaranteed free of pathogens. In this article, we investigated the use of a new mass spectrometric approach for fast and accurate identification of bacteria and fungi in bovine semen and in culture media employed in the embryo in vitro production process. The microorganisms isolated from samples obtained in a commercial bovine embryo IVP setting were identified in a few minutes by their conserved peptide/protein profile, obtained applying matrix-assisted laser desorption ionization mass spectrometry (MALDI-MS), matched against a commercial database. The successful microorganisms MS identification has been confirmed by DNA amplification and sequencing. Therefore, the MS technique seems to offer a powerful tool for rapid and accurate microorganism identification in semen and culture media samples. Copyright © 2013 Elsevier Inc. All rights reserved.

  11. Direct identification of microorganisms from positive blood cultures using the lysis-filtration technique and matrix assisted laser desorption ionization time-of-flight mass spectrometry (MALDI-TOF MS): a multicentre study.

    Science.gov (United States)

    Farina, Claudio; Arena, Fabio; Casprini, Patrizia; Cichero, Paola; Clementi, Massimo; Cosentino, Marina; Degl'Innocenti, Roberto; Giani, Tommaso; Luzzaro, Francesco; Mattei, Romano; Mauri, Carola; Nardone, Maria; Rossolini, Gian Maria; Serna Ortega, Paula Andrea; Vailati, Francesca

    2015-04-01

    Microbial identification from blood cultures is essential to institute optimal antibiotic therapy and improve survival possibilities. Matrix-assisted laser desorption ionization-time of flight mass spectrometry (MALDI-TOF MS) has been successfully applied to identify bacteria and yeasts from positive blood cultures broths. The aim of this multicentre study was to evaluate the reliability of the lysis-filtration technique associated with MALDI-TOF MS to directly identify microorganisms from 765 positive blood cultures collected in six Italian hospitals. Overall, 675/765 (78.1%) blood isolates were correctly identified at the species level, with significant differences between Gram-negative and Gram-positive bacteria (92.6%, and 69.8%, respectively). Some difficulties arise in identifying Streptococcus pneumoniae, Staphylococcus aureus, yeasts and anaerobes. The lysis-filtration protocol is a suitable procedure in terms of performance in identifying microorganisms, but it is quite expensive and technically time-consuming since the time of filtration is not regular for all the samples. The application of the MALDI-TOF MS technique to the direct microbial identification from positive blood cultures is a very promising approach, even if more experience must be gained to minimize errors and costs.

  12. Direct identification by matrix-assisted laser desorption ionization-time of flight mass spectrometry (MALDI-TOF MS from positive blood culture bottles: An opportunity to customize growth conditions for fastidious organisms causing bloodstream infections

    Directory of Open Access Journals (Sweden)

    Megha Sharma

    2017-01-01

    Full Text Available Culture-negative bacteraemia has been an enigmatic entity with respect to its aetiological agents. In an attempt to actively identify those positive blood cultures that escape isolation and detection on routine workflow, an additional step of MALDI-TOF MS (matrix-assisted laser desorption ionization-time of flight mass spectrometry based detection was carried out directly from the flagged blood culture bottles. Blood samples from 200 blood culture bottles that beeped positive with automated (BACTEC system and showed no growth of organism on routine culture media, were subjected to analysis by MALDI-TOF MS. Forty seven of the 200 (23.5% bacterial aetiology could be established by bottle-based method. Based on these results, growth on culture medium could be achieved for the isolates by providing special growth conditions to the fastidious organisms. Direct identification by MALDI-TOF MS from BACTEC-positive bottles provided an opportunity to isolate those fastidious organisms that failed to grow on routine culture medium by providing them with necessary alterations in growth environment.

  13. Direct identification by matrix-assisted laser desorption ionization-time of flight mass spectrometry (MALDI-TOF MS) from positive blood culture bottles: An opportunity to customize growth conditions for fastidious organisms causing bloodstream infections.

    Science.gov (United States)

    Sharma, Megha; Gautam, Vikas; Mahajan, Monika; Rana, Sudesh; Majumdar, Manasi; Ray, Pallab

    2017-10-01

    Culture-negative bacteraemia has been an enigmatic entity with respect to its aetiological agents. In an attempt to actively identify those positive blood cultures that escape isolation and detection on routine workflow, an additional step of MALDI-TOF MS (matrix-assisted laser desorption ionization-time of flight mass spectrometry) based detection was carried out directly from the flagged blood culture bottles. Blood samples from 200 blood culture bottles that beeped positive with automated (BACTEC) system and showed no growth of organism on routine culture media, were subjected to analysis by MALDI-TOF MS. Forty seven of the 200 (23.5%) bacterial aetiology could be established by bottle-based method. Based on these results, growth on culture medium could be achieved for the isolates by providing special growth conditions to the fastidious organisms. Direct identification by MALDI-TOF MS from BACTEC-positive bottles provided an opportunity to isolate those fastidious organisms that failed to grow on routine culture medium by providing them with necessary alterations in growth environment.

  14. Real-time analysis of aromatics in combustion engine exhaust by resonance-enhanced multiphoton ionisation time-of-flight mass spectrometry (REMPI-TOF-MS): a robust tool for chassis dynamometer testing

    Energy Technology Data Exchange (ETDEWEB)

    Adam, T.W. [European Commission Joint Research Centre, Institute for Environment and Sustainability, Transport and Air Quality Unit, Ispra, VA (Italy); Clairotte, M.; Manfredi, U.; Carriero, M.; Martini, G.; Krasenbrink, A.; Astorga, C. [European Commission Joint Research Centre, Institute for Environment and Sustainability, Transport and Air Quality Unit, Ispra, VA (Italy); European Commission Joint Research Centre, Institute for Energy and Transport, Sustainable Transport Unit, Ispra, Varese (Italy); Streibel, T.; Pommeres, A.; Sklorz, M. [University of Rostock, Analytical Chemistry/Joint Mass Spectrometry Centre, Institute of Chemistry, Rostock (Germany); Elsasser, M.; Zimmermann, R. [Cooperation Group Complex Molecular Systems (CMA)/Joint Mass Spectrometry Centre (JMSC), Neuherberg (Germany); University of Rostock, Analytical Chemistry/Joint Mass Spectrometry Centre, Institute of Chemistry, Rostock (Germany)

    2012-07-15

    Resonance-enhanced multiphoton ionisation time-of-flight mass spectrometry (REMPI-TOF-MS) is a robust method for real-time analysis of monocyclic and polycyclic aromatic hydrocarbons in complex emissions. A mobile system has been developed which enables direct analysis on site. In this paper, we utilize a multicomponent calibration scheme based on the analytes' photo-ionisation cross-sections relative to a calibrated species. This allows semi-quantification of a great number of components by only calibrating one compound of choice, here toluene. The cross-sections were determined by injecting nebulised solutions of aromatic compounds into the TOF-MS ion source with the help of a HPLC pump. Then, REMPI-TOF-MS was implemented at various chassis dynamometers and test cells and the exhaust of the following vehicles and engines investigated: a compression ignition light-duty (LD) passenger car, a compression ignition LD van, two spark ignition LD passenger cars, 2 two-stroke mopeds, and a two-stroke engine of a string gas trimmer. The quantitative time profiles of benzene are shown. The results indicate that two-stroke engines are a significant source for toxic and cancerogenic compounds. Air pollution and health effects caused by gardening equipment might still be underestimated. (orig.)

  15. Elemental mapping in fossil tooth root section of Ursus arctos by laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS)

    Czech Academy of Sciences Publication Activity Database

    Vašinová Galiová, M.; Nývltová Fišáková, Miriam; Kynický, J.; Prokeš, L.; Neff, H.; Mason, A. Z.; Gadas, P.; Košler, J.; Kanický, V.

    2013-01-01

    Roč. 105, 15 February 2013 (2013), s. 235-243 ISSN 0039-9140 Institutional research plan: CEZ:AV0Z80010507 Institutional support: RVO:68081758 Keywords : Diagenesis * Diet * Geochemical analysis * Laser ablation ICP-MS * Migration Subject RIV: AC - Archeology, Anthropology, Ethnology Impact factor: 3.511, year: 2013

  16. A longitudinal study of ammonia, acetone and propanol in the exhaled breath of 30 subjects using selected ion flow tube mass spectrometry, SIFT-MS

    Czech Academy of Sciences Publication Activity Database

    Turner, C.; Španěl, Patrik; Smith, D.

    2006-01-01

    Roč. 27, č. 4 (2006), s. 321-337 ISSN 0967-3334 Institutional research plan: CEZ:AV0Z40400503 Keywords : breath analysis * metabolites * ammonia * acetone * SIFT-MS Subject RIV: CF - Physical ; Theoretical Chemistry Impact factor: 1.438, year: 2006

  17. Influence of weakly bound adduct ions on breath trace gas analysis by selected ion flow tube mass spectrometry (SIFT-MS)

    Czech Academy of Sciences Publication Activity Database

    Španěl, Patrik; Smith, D.

    2009-01-01

    Roč. 280, 1-3 (2009), s. 128-135 ISSN 1387-3806 R&D Projects: GA AV ČR IAA400400702 Institutional research plan: CEZ:AV0Z40400503 Keywords : ion-molecule association * adduct ion * SIFT-MS * breath analysis Subject RIV: CF - Physical ; Theoretical Chemistry Impact factor: 2.117, year: 2009

  18. In-tube collision-induced dissociation for selected ion flow-drift tube mass spectrometry, SIFDT-MS: a case study of NO+ reactions with isomeric monoterpenes

    Czech Academy of Sciences Publication Activity Database

    Spesyvyi, Anatolii; Sovová, Kristýna; Španěl, Patrik

    2016-01-01

    Roč. 30, č. 18 (2016), s. 2009-2016 ISSN 0951-4198 R&D Projects: GA ČR GA13-28882S Institutional support: RVO:61388955 Keywords : mass spectroscopy * SIFDT-MS * isomeric monoterpenes Subject RIV: CF - Physical ; Theoretical Chemistry Impact factor: 1.998, year: 2016

  19. Identification and Evaluation of Clinically Significant Nocardia brasiliensis, Nocardia farcinica and Nocardia otitidiscaviarum Strains Using Pyrolysis Mass Spectrometry (PyMS)

    OpenAIRE

    IŞIK, Kamil; KARİPTAŞ, Ergin; ŞAHİN, Nevzat

    2001-01-01

    Out of a total of thirty-nine Nocardia strains, eight species of N. brasiliensis, seventeen species of N. farcinica and fourteen species of N. otitidiscaviarum were identified using Pyrolysis mass spectrometry. N428, N477 N. brasiliensis; N669, N233 N. farcinica; and N231, N232 N. otitidiscaviarum duplicated strains were clustered in their own groups. Strains belonging to Nocardia brasiliensis, Nocardia farcinica and Nocardia otitidiscaviarum formed distinct pyrogroups corresponding to cluste...

  20. Stepped MS(All) Relied Transition (SMART): An approach to rapidly determine optimal multiple reaction monitoring mass spectrometry parameters for small molecules.

    Science.gov (United States)

    Ye, Hui; Zhu, Lin; Wang, Lin; Liu, Huiying; Zhang, Jun; Wu, Mengqiu; Wang, Guangji; Hao, Haiping

    2016-02-11

    Multiple reaction monitoring (MRM) is a universal approach for quantitative analysis because of its high specificity and sensitivity. Nevertheless, optimization of MRM parameters remains as a time and labor-intensive task particularly in multiplexed quantitative analysis of small molecules in complex mixtures. In this study, we have developed an approach named Stepped MS(All) Relied Transition (SMART) to predict the optimal MRM parameters of small molecules. SMART requires firstly a rapid and high-throughput analysis of samples using a Stepped MS(All) technique (sMS(All)) on a Q-TOF, which consists of serial MS(All) events acquired from low CE to gradually stepped-up CE values in a cycle. The optimal CE values can then be determined by comparing the extracted ion chromatograms for the ion pairs of interest among serial scans. The SMART-predicted parameters were found to agree well with the parameters optimized on a triple quadrupole from the same vendor using a mixture of standards. The parameters optimized on a triple quadrupole from a different vendor was also employed for comparison, and found to be linearly correlated with the SMART-predicted parameters, suggesting the potential applications of the SMART approach among different instrumental platforms. This approach was further validated by applying to simultaneous quantification of 31 herbal components in the plasma of rats treated with a herbal prescription. Because the sMS(All) acquisition can be accomplished in a single run for multiple components independent of standards, the SMART approach are expected to find its wide application in the multiplexed quantitative analysis of complex mixtures. Copyright © 2015 Elsevier B.V. All rights reserved.

  1. Electrothermal vaporisation ICP-mass spectrometry (ETV-ICP-MS) for the determination and speciation of trace elements in solid samples - A review of real-life applications from the author's lab

    Energy Technology Data Exchange (ETDEWEB)

    Vanhaecke, Frank; Resano, Martin; Moens, Luc [Laboratory of Analytical Chemistry, Ghent University, Institute for Nuclear Sciences, Proeftuinstraat 86, 9000 Ghent (Belgium)

    2002-09-01

    The use of electrothermal vaporisation (ETV) from a graphite furnace as a means of sample introduction in inductively coupled plasma mass spectrometry (ICP-MS) permits the direct analysis of solid samples. A multi-step furnace temperature programme is used to separate the vaporisation of the target element(s) and of the matrix components from one another. Sometimes, a chemical modifier is used to enable a higher thermal pre-treatment temperature, by avoiding premature analyte losses (stabilisation) or promoting the selective volatilisation of matrix components. In almost all instances, accurate results can be obtained via external calibration or single standard addition using an aqueous standard solution. Absolute limits of detection are typically 1 pg, which corresponds to 1 ng/g for a typical sample mass of 1 mg. Real-life applications carried out in the author's lab are used to illustrate the utility of this approach. These applications aim at trace element determination in industrial and environmental materials. The industrial materials analysed include different types of plastics - Carilon, polyethylene, poly(ethyleneterephtalate) and polyamide - and photo- and thermographic materials. As samples from environmental origin, plant material, animal tissue and sediments were investigated. Some applications aimed at a multi-element determination, while in other, the content of a single, but often challenging, element (e.g., Si or S) had to be measured. ETV-ICP-MS was also used in elemental speciation studies. Separation of Se-containing proteins was accomplished using polyacrylamide gel electrophoresis (PAGE). Subsequent quantification of the Se content in the protein spots was carried out using ETV-ICP-MS. As the volatilisation of methylmercury and inorganic mercury could be separated from one another with respect to time, no chromatographic or electrophoretic separation procedure was required, but ETV-ICP-MS as such sufficed for Hg speciation in fish tissue

  2. Optimization of a two-dimensional liquid chromatography-supercritical fluid chromatography-mass spectrometry (2D-LC-SFS-MS) system to assess "in-vivo" inter-conversion of chiral drug molecules.

    Science.gov (United States)

    Goel, Meenakshi; Larson, Eli; Venkatramani, C J; Al-Sayah, Mohammad A

    2018-05-01

    Enantioselective analysis is an essential requirement during the pharmaceutical development of chiral drug molecules. In pre-clinical and clinical studies, the Food and Drug Administration (FDA) mandates the assessment of "in vivo" inter-conversion of chiral drugs to determine their physiological effects. In-vivo analysis of the active pharmaceutical ingredient (API) and its potential metabolites could be quite challenging due to their low abundance (ng/mL levels) and matrix interferences. Therefore, highly selective and sensitive analytical techniques are required to separate the API and its metabolites from the matrix components and one another. Additionally, for chiral APIs, further analytical separation is required to resolve the API and its potential metabolites from their corresponding enantiomers. In this work, we demonstrate the optimization of our previously designed two-dimensional liquid chromatography-supercritical fluid chromatography-mass spectrometry (2D-LC-SFC -MS) system to achieve 10 ng/mL detection limit [1]. The first LC dimension, used as a desalting step, could efficiently separate the API from its potential metabolites and matrix components. The API and its metabolites were then trapped/focused on small trapping columns and transferred onto the second SFC dimension for chiral separation. Detection can be achieved by ultra-violet (UV) or MS detection. Different system parameters such as column dimensions, transfer volumes, trapping column stationary phase, system tubing internal diameter (i.d.), and detection techniques, were optimized to enhance the sensitivity of the 2D-LC-SFC-MS system. The limit of detection was determined to be 10 ng/mL. An application is described where a mouse hepatocyte treated sample was analyzed using the optimized 2D-LC-SFC-MS system with successful assessment of the ratio of API to its metabolite (1D-LC), as well as the corresponding enantiomeric excess values (% e.e.) of each (2D-SFC). Copyright © 2018

  3. Identification of the Metabolic Enzyme Involved Morusin Metabolism and Characterization of Its Metabolites by Ultraperformance Liquid Chromatography Quadrupole Time-of-Flight Mass Spectrometry (UPLC/Q-TOF-MS/MS

    Directory of Open Access Journals (Sweden)

    Xianbao Shi

    2016-01-01

    Full Text Available Morusin, the important active component of a traditional Chinese medicine, Morus alba L., has been shown to exhibit many vital pharmacological activities. In this study, six recombinant CYP450 supersomes and liver microsomes were used to perform metabolic studies. Chemical inhibition studies and screening assays with recombinant human cytochrome P450s were also used to characterize the CYP450 isoforms involved in morusin metabolism. The morusin metabolites identified varied greatly among different species. Eight metabolites of morusin were detected in the liver microsomes from pigs (PLMs, rats (RLMs, and monkeys (MLMs by LC-MS/MS and six metabolites were detected in the liver microsomes from humans (HLMs, rabbits (RAMs, and dogs (DLMs. Four metabolites (M1, M2, M5, and M7 were found in all species and hydroxylation was the major metabolic transformation. CYP1A2, CYP2C9, CYP2D6, CYP2E1, CYP3A4, and CYP2C19 contributed differently to the metabolism of morusin. Compared to other CYP450 isoforms, CYP3A4 played the most significant role in the metabolism of morusin in human liver microsomes. These results are significant to better understand the metabolic behaviors of morusin among various species.

  4. Fast Detection of Phenolic Compounds in Extracts of Easter Pears (Pyrus communis) from the Atacama Desert by Ultrahigh-Performance Liquid Chromatography and Mass Spectrometry (UHPLC-Q/Orbitrap/MS/MS).

    Science.gov (United States)

    Simirgiotis, Mario J; Quispe, Cristina; Bórquez, Jorge; Areche, Carlos; Sepúlveda, Beatriz

    2016-01-15

    A small Chilean variety of pears growing in the town of Toconao, an oasis located at the northeastern edge of the Salar de Atacama, northern Chile, was studied by means of modern PDA and high resolution mass spectral data (UHPLC-PDA-HESI-orbitrap-MS/MS). In addition, the antioxidant features of the fruits were compared with the varieties Packhman's Triumph and Abate Fetel and correlated with the presence of phenolic compounds. The non-pigmented phenolics were fingerprinted and related to the antioxidant capacities measured by the bleaching of the DPPH radical, the ferric reducing antioxidant power (FRAP), the superoxide anion scavenging activity assay (SA), and total content of phenolics and flavonoids measured by spectroscopic methods. The machine allowed a fast separation of 15 min employing a flow rate of 1 mL per minute and could accurately identify 25 compounds, including several isorhamnetin derivatives and phenolic acids, present in the peel and pulps of this Chilean variety for the first time. The compounds were monitored using a wavelength range of 210-800 nm. The native small Chilean pear showed the highest antioxidant activity measured as the bleaching of the DPPH radical, the ferric reducing antioxidant power and superoxide anion scavenging activity (8.61 ± 0.65 μg/mL, 712.63 ± 12.12 micromols trolox equivalents (μmol/TE)/100 g FW, and 82.89% ± 2.52% at 100 μg/mL, respectively).

  5. The collaboratory for MS3D: a new cyberinfrastructure for the structural elucidation of biological macromolecules and their assemblies using mass spectrometry-based approaches.

    Science.gov (United States)

    Yu, Eizadora T; Hawkins, Arie; Kuntz, Irwin D; Rahn, Larry A; Rothfuss, Andrew; Sale, Kenneth; Young, Malin M; Yang, Christine L; Pancerella, Carmen M; Fabris, Daniele

    2008-11-01

    Modern biomedical research is evolving with the rapid growth of diverse data types, biophysical characterization methods, computational tools and extensive collaboration among researchers spanning various communities and having complementary backgrounds and expertise. Collaborating researchers are increasingly dependent on shared data and tools made available by other investigators with common interests, thus forming communities that transcend the traditional boundaries of the single research laboratory or institution. Barriers, however, remain to the formation of these virtual communities, usually due to the steep learning curve associated with becoming familiar with new tools, or with the difficulties associated with transferring data between tools. Recognizing the need for shared reference data and analysis tools, we are developing an integrated knowledge environment that supports productive interactions among researchers. Here we report on our current collaborative environment, which focuses on bringing together structural biologists working in the area of mass spectrometric based methods for the analysis of tertiary and quaternary macromolecular structures (MS3D) called the Collaboratory for MS3D (C-MS3D). C-MS3D is a Web-portal designed to provide collaborators with a shared work environment that integrates data storage and management with data analysis tools. Files are stored and archived along with pertinent meta data in such a way as to allow file handling to be tracked (data provenance) and data files to be searched using keywords and modification dates. While at this time the portal is designed around a specific application, the shared work environment is a general approach to building collaborative work groups. The goal of this is to not only provide a common data sharing and archiving system, but also to assist in the building of new collaborations and to spur the development of new tools and technologies.

  6. Analysis of the isobaric compounds propanol, acetic acid and methyl formate in humid air and breath by selected ion flow tube mass spectrometry, SIFT-MS

    Czech Academy of Sciences Publication Activity Database

    Pysanenko, A.; Španěl, Patrik; Smith, D.

    2009-01-01

    Roč. 285, 1-2 (2009), s. 42-48 ISSN 1387-3806 R&D Projects: GA ČR GA203/09/0256; GA ČR GA202/09/0800 Institutional research plan: CEZ:AV0Z40400503 Keywords : SIFT-MS * isobaric compound * propanol * acetic acid Subject RIV: CF - Physical ; Theoretical Chemistry Impact factor: 2.117, year: 2009

  7. Differentiation of clinically relevant Mucorales Rhizopus microsporus and R. arrhizus by matrix-assisted laser desorption ionization time-of-flight mass spectrometry (MALDI-TOF MS).

    Science.gov (United States)

    Dolatabadi, Somayeh; Kolecka, Anna; Versteeg, Matthijs; de Hoog, Sybren G; Boekhout, Teun

    2015-07-01

    This study addresses the usefulness of matrix-assisted laser desorption ionization time-of-flight (MALDI-TOF) MS for reliable identification of the two most frequently occurring clinical species of Rhizopus, namely Rhizopus arrhizus with its two varieties, arrhizus and delemar, and Rhizopus microsporus. The test-set comprised 38 isolates of clinical and environmental origin previously identified by internal transcribed spacer (ITS) sequencing of rDNA. Multi-locus sequence data targeting three gene markers (ITS, ACT, TEF ) showed two monophylic clades for Rhizopus arrhizus and Rhizopus microsporus (bootstrap values of 99 %). Cluster analysis confirmed the presence of two distinct clades within Rhizopus arrhizus representing its varieties arrhizus and delemar. The MALDI Biotyper 3.0 Microflex LT platform (Bruker Daltonics) was used to confirm the distinction between Rhizopus arrhizus and Rhizopus microsporus and the presence of two varieties within the species Rhizopus arrhizus. An in-house database of 30 reference main spectra (MSPs) was initially tested for correctness using commercially available databases of Bruker Daltonics. By challenging the database with the same strains of which an in-house database was created, automatic identification runs confirmed that MALDI-TOF MS is able to recognize the strains at the variety level. Based on principal component analysis, two MSP dendrograms were created and showed concordance with the multi-locus tree; thus, MALDI-TOF MS is a useful tool for diagnostics of mucoralean species.

  8. Hydrogen Exchange Mass Spectrometry

    Science.gov (United States)

    Mayne, Leland

    2018-01-01

    Hydrogen exchange (HX) methods can reveal much about the structure, energetics, and dynamics of proteins. The addition of mass spectrometry (MS) to an earlier fragmentation-separation HX analysis now extends HX studies to larger proteins at high structural resolution and can provide information not available before. This chapter discusses experimental aspects of HX labeling, especially with respect to the use of MS and the analysis of MS data. PMID:26791986

  9. Determination of (90)Sr in soil samples using inductively coupled plasma mass spectrometry equipped with dynamic reaction cell (ICP-DRC-MS).

    Science.gov (United States)

    Feuerstein, J; Boulyga, S F; Galler, P; Stingeder, G; Prohaska, T

    2008-11-01

    A rapid method is reported for the determination of (90)Sr in contaminated soil samples in the vicinity of the Chernobyl Nuclear Power Plant by ICP-DRC-MS. Sample preparation and measurement procedures focus on overcoming the isobaric interference of (90)Zr, which is present in soils at concentrations higher by more than six orders of magnitude than (90)Sr. Zirconium was separated from strontium in two steps to reduce the interference by (90)Zr(+) ions by a factor of more than 10(7): (i) by ion exchange using a Sr-specific resin and (ii) by reaction with oxygen as reaction gas in a dynamic reaction cell (DRC) of a quadrupole ICP-MS. The relative abundance sensitivity of the ICP-MS was studied systematically and the peak tailing originating from (88)Sr on mass 90 u was found to be about 3 x 10(-9). Detection limits of 4 fg g(-1) (0.02 Bq g(-1)) were achieved when measuring Sr solutions containing no Zr. In digested uncontaminated soil samples after matrix separation as well as in a solution of 5 microg g(-1) Sr and 50 ng g(-1) Zr a detection limit of 0.2 pg g(-1) soil (1 Bq g(-1) soil) was determined. (90)Sr concentrations in three soil samples collected in the vicinity of the Chernobyl Nuclear Power Plant were 4.66+/-0.27, 13.48+/-0.68 and 12.9+/-1.5 pg g(-1) corresponding to specific activities of 23.7+/-1.3, 68.6+/-3.5 and 65.6+/-7.8 Bq g(-1), respectively. The ICP-DRC-MS results were compared to the activities measured earlier by radiometry. Although the ICP-DRC-MS is inferior to commonly used radiometric methods with respect to the achievable minimum detectable activity it represents a time- and cost-effective alternative technique for fast monitoring of high-level (90)Sr contamination in environmental or nuclear industrial samples down to activities of about 1 Bq g(-1).

  10. Determination of 90Sr in soil samples using inductively coupled plasma mass spectrometry equipped with dynamic reaction cell (ICP-DRC-MS)

    International Nuclear Information System (INIS)

    Feuerstein, J.; Boulyga, S.F.; Galler, P.; Stingeder, G.; Prohaska, T.

    2008-01-01

    A rapid method is reported for the determination of 90 Sr in contaminated soil samples in the vicinity of the Chernobyl Nuclear Power Plant by ICP-DRC-MS. Sample preparation and measurement procedures focus on overcoming the isobaric interference of 90 Zr, which is present in soils at concentrations higher by more than six orders of magnitude than 90 Sr. Zirconium was separated from strontium in two steps to reduce the interference by 90 Zr + ions by a factor of more than 10 7 : (i) by ion exchange using a Sr-specific resin and (ii) by reaction with oxygen as reaction gas in a dynamic reaction cell (DRC) of a quadrupole ICP-MS. The relative abundance sensitivity of the ICP-MS was studied systematically and the peak tailing originating from 88 Sr on mass 90 u was found to be about 3 x 10 -9 . Detection limits of 4 fg g -1 (0.02 Bq g -1 ) were achieved when measuring Sr solutions containing no Zr. In digested uncontaminated soil samples after matrix separation as well as in a solution of 5 μg g -1 Sr and 50 ng g -1 Zr a detection limit of 0.2 pg g -1 soil (1 Bq g -1 soil) was determined. 90 Sr concentrations in three soil samples collected in the vicinity of the Chernobyl Nuclear Power Plant were 4.66 ± 0.27, 13.48 ± 0.68 and 12.9 ± 1.5 pg g -1 corresponding to specific activities of 23.7 ± 1.3, 68.6 ± 3.5 and 65.6 ± 7.8 Bq g -1 , respectively. The ICP-DRC-MS results were compared to the activities measured earlier by radiometry. Although the ICP-DRC-MS is inferior to commonly used radiometric methods with respect to the achievable minimum detectable activity it represents a time- and cost-effective alternative technique for fast monitoring of high-level 90 Sr contamination in environmental or nuclear industrial samples down to activities of about 1 Bq g -1

  11. Determination of {sup 90}Sr in soil samples using inductively coupled plasma mass spectrometry equipped with dynamic reaction cell (ICP-DRC-MS)

    Energy Technology Data Exchange (ETDEWEB)

    Feuerstein, J.; Boulyga, S.F.; Galler, P.; Stingeder, G. [Department of Chemistry, Division of Analytical Chemistry-VIRIS Laboratory, University of Natural Resources and Applied Life Sciences, Muthgasse 18, A-1190 Vienna (Austria); Prohaska, T. [Department of Chemistry, Division of Analytical Chemistry-VIRIS Laboratory, University of Natural Resources and Applied Life Sciences, Muthgasse 18, A-1190 Vienna (Austria)], E-mail: thomas.prohaska@boku.ac.at

    2008-11-15

    A rapid method is reported for the determination of {sup 90}Sr in contaminated soil samples in the vicinity of the Chernobyl Nuclear Power Plant by ICP-DRC-MS. Sample preparation and measurement procedures focus on overcoming the isobaric interference of {sup 90}Zr, which is present in soils at concentrations higher by more than six orders of magnitude than {sup 90}Sr. Zirconium was separated from strontium in two steps to reduce the interference by {sup 90}Zr{sup +} ions by a factor of more than 10{sup 7}: (i) by ion exchange using a Sr-specific resin and (ii) by reaction with oxygen as reaction gas in a dynamic reaction cell (DRC) of a quadrupole ICP-MS. The relative abundance sensitivity of the ICP-MS was studied systematically and the peak tailing originating from {sup 88}Sr on mass 90 u was found to be about 3 x 10{sup -9}. Detection limits of 4 fg g{sup -1} (0.02 Bq g{sup -1}) were achieved when measuring Sr solutions containing no Zr. In digested uncontaminated soil samples after matrix separation as well as in a solution of 5 {mu}g g{sup -1} Sr and 50 ng g{sup -1} Zr a detection limit of 0.2 pg g{sup -1} soil (1 Bq g{sup -1} soil) was determined. {sup 90}Sr concentrations in three soil samples collected in the vicinity of the Chernobyl Nuclear Power Plant were 4.66 {+-} 0.27, 13.48 {+-} 0.68 and 12.9 {+-} 1.5 pg g{sup -1} corresponding to specific activities of 23.7 {+-} 1.3, 68.6 {+-} 3.5 and 65.6 {+-} 7.8 Bq g{sup -1}, respectively. The ICP-DRC-MS results were compared to the activities measured earlier by radiometry. Although the ICP-DRC-MS is inferior to commonly used radiometric methods with respect to the achievable minimum detectable activity it represents a time- and cost-effective alternative technique for fast monitoring of high-level {sup 90}Sr contamination in environmental or nuclear industrial samples down to activities of about 1 Bq g{sup -1}.

  12. Forensic investigation of brick stones using instrumental neutron activation analysis (INAA), laser ablation-inductively coupled plasma-mass spectrometry (LA-ICP-MS) and X-ray fluorescence analysis (XRF)

    International Nuclear Information System (INIS)

    Scheid, Nicole; Becker, Stefan; Duecking, Marc; Hampel, Gabriele; Volker Kratz, Jens; Watzke, Peter; Weis, Peter; Zauner, Stephan

    2009-01-01

    Brick stones collected from different production facilities were studied for their elemental compositions under forensic aspects using laser ablation-inductively coupled plasma-mass spectrometry (LA-ICP-MS), instrumental neutron activation analysis (INAA) and X-ray fluorescence analysis (XRF). The aim of these examinations was to assess the potential of these methods in forensic comparison analyses of brick stones. The accuracy of the analysis methods was evaluated using NIST standard reference materials (679, 98b and 97b). In order to compare the stones to each other, multivariate data analysis was used. The evaluation of the INAA results (based on the concentrations of V, Na, K, Sm, U, Sc, Fe, Co, Rb and Cs) using principal component analysis (PCA) and cluster analysis is presented as an example. The results derived from the different analytical methods are consistent. It was shown that elemental analysis using the described methods is a valuable tool for forensic examinations of brick stones.

  13. Detailed characterization of bio-oil from pyrolysis of non-edible seed-cakes by Fourier Transform Infrared Spectroscopy (FTIR) and gas chromatography mass spectrometry (GC-MS) techniques.

    Science.gov (United States)

    Sugumaran, Vatsala; Prakash, Shanti; Ramu, Emmandi; Arora, Ajay Kumar; Bansal, Veena; Kagdiyal, Vivekanand; Saxena, Deepak

    2017-07-15

    Bio-oil obtained from pyrolysis is highly complicated mixture with valued chemicals. In order to reduce the complexity for unambiguous characterization of components present in bio-oil, solvent extractions using different solvents with increasing polarity have been adopted. The fractions have been analyzed by Fourier transform infrared (FTIR) spectroscopy for identifying the functional groups and Gas chromatography-mass spectrometry (GC-MS), for detailed characterization of components present in various fractions, thereby providing in-depth information at molecular level of various components in bio-oil. This paper reveals the potential of the analytical techniques in identification and brings out the similarities as well as differences in the components present in the bio-oil obtained from two non-edible oil seed-cakes, viz., Jatropha and Karanjia. Copyright © 2017 Elsevier B.V. All rights reserved.

  14. Residue depletion of oxytetracycline (OTC) and 4-epi-oxytetracycline (4-epi-OTC) in broiler chicken's claws by liquid chromatography-tandem mass spectrometry (LC-MS/MS).

    Science.gov (United States)

    Cornejo, J; Pokrant, E; Araya, D; Briceño, C; Hidalgo, H; Maddaleno, A; Araya-Jordán, C; San Martin, B

    2017-04-01

    Antibiotics are widely used in poultry production for the treatment of bacterial diseases. However, residues may remain in products and by-products destined for human consumption or animal feeding. The claws of chickens, which are a by-product of the poultry industry, can directly or indirectly enter the food chain as meals destined to feed other productive animals. Thus, it becomes necessary to determine and quantify antimicrobial residues present in this matrix. The objective of the study was to assess the depletion of oxytetracycline (OTC) and its metabolite 4-epi-OTC in broiler chicken's claws. Claws of 32 broilers treated with a therapeutic dosage of 10% OTC during 7 days were analysed. Samples were taken at days 3, 9, 15 and 19 post-treatment. As for the control group, eight broiler chickens were raised under the same conditions. Extraction was carried out through EDTA-McIlvaine buffer, and clean-up employed a SPE C-18 Sep-Pak®. Instrumental analysis was performed through LC-MS/MS. The concentrations of both analytes were determined in claw samples until day 19 post-treatment. Average concentrations were within the LOD (20 μg kg - 1 ) and LOQ (22 µg kg - 1 ) for OTC and 84 μg kg - 1 for 4-epi-OTC. Withdrawal times (WDTs) of 39 days for OTC and 54 days for 4-epi-OTC were established in claws based on 95% confidence. These findings demonstrate that claws can be a source of antimicrobial residue entry into the food chain, since the results showed that OTC and its metabolite can be found in chicken's claws for long periods, even exceeding the average lifespan of a broiler chicken.

  15. Development of decision tree software and protein profiling using surface enhanced laser desorption/ionization-time of flight-mass spectrometry (SELDI-TOF-MS) in papillary thyroid cancer

    International Nuclear Information System (INIS)

    Yoon, Joon Kee; An, Young Sil; Park, Bok Nam; Yoon, Seok Nam; Lee, Jun

    2007-01-01

    The aim of this study was to develop a bioinformatics software and to test it in serum samples of papillary thyroid cancer using mass spectrometry (SELDI-TOF-MS). Development of 'Protein analysis' software performing decision tree analysis was done by customizing C4.5. Sixty-one serum samples from 27 papillary thyroid cancer, 17 autoimmune thyroiditis, 17 controls were applied to 2 types of protein chips, CM10 (weak cation exchange) and IMAC3 (metal binding - Cu). Mass spectrometry was performed to reveal the protein expression profiles. Decision trees were generated using 'Protein analysis' software, and automatically detected biomarker candidates. Validation analysis was performed for CM10 chip by random sampling. Decision tree software, which can perform training and validation from profiling data, was developed. For CM10 and IMAC3 chips, 23 of 113 and 8 of 41 protein peaks were significantly different among 3 groups (ρ < 0.05), respectively. Decision tree correctly classified 3 groups with an error rate of 3.3% for CM10 and 2.0% for IMAC3, and 4 and 7 biomarker candidates were detected respectively. In 2 group comparisons, all cancer samples were correctly discriminated from non-cancer samples (error rate = 0%) for CM10 by single node and for IMAC3 by multiple nodes. Validation results from 5 test sets revealed SELDI-TOF-MS and decision tree correctly differentiated cancers from non-cancers (54/55, 98%), while predictability was moderate in 3 group classification (36/55, 65%). Our in-house software was able to successfully build decision trees and detect biomarker candidates, therefore it could be useful for biomarker discovery and clinical follow up of papillary thyroid cancer

  16. Development of decision tree software and protein profiling using surface enhanced laser desorption/ionization-time of flight-mass spectrometry (SELDI-TOF-MS) in papillary thyroid cancer

    Energy Technology Data Exchange (ETDEWEB)

    Yoon, Joon Kee; An, Young Sil; Park, Bok Nam; Yoon, Seok Nam [Ajou University School of Medicine, Suwon (Korea, Republic of); Lee, Jun [Konkuk University, Seoul (Korea, Republic of)

    2007-08-15

    The aim of this study was to develop a bioinformatics software and to test it in serum samples of papillary thyroid cancer using mass spectrometry (SELDI-TOF-MS). Development of 'Protein analysis' software performing decision tree analysis was done by customizing C4.5. Sixty-one serum samples from 27 papillary thyroid cancer, 17 autoimmune thyroiditis, 17 controls were applied to 2 types of protein chips, CM10 (weak cation exchange) and IMAC3 (metal binding - Cu). Mass spectrometry was performed to reveal the protein expression profiles. Decision trees were generated using 'Protein analysis' software, and automatically detected biomarker candidates. Validation analysis was performed for CM10 chip by random sampling. Decision tree software, which can perform training and validation from profiling data, was developed. For CM10 and IMAC3 chips, 23 of 113 and 8 of 41 protein peaks were significantly different among 3 groups ({rho} < 0.05), respectively. Decision tree correctly classified 3 groups with an error rate of 3.3% for CM10 and 2.0% for IMAC3, and 4 and 7 biomarker candidates were detected respectively. In 2 group comparisons, all cancer samples were correctly discriminated from non-cancer samples (error rate = 0%) for CM10 by single node and for IMAC3 by multiple nodes. Validation results from 5 test sets revealed SELDI-TOF-MS and decision tree correctly differentiated cancers from non-cancers (54/55, 98%), while predictability was moderate in 3 group classification (36/55, 65%). Our in-house software was able to successfully build decision trees and detect biomarker candidates, therefore it could be useful for biomarker discovery and clinical follow up of papillary thyroid cancer.

  17. The Role of Ultrahigh Resolution Fourier Transform Mass Spectrometry (FT-MS) in Astrobiology-Related Research: Analysis of Meteorites and Tholins.

    Science.gov (United States)

    Somogyi, Árpád; Thissen, Roland; Orthous-Daunay, Francois-Régis; Vuitton, Véronique

    2016-03-24

    It is an important but also a challenging analytical problem to understand the chemical composition and structure of prebiotic organic matter that is present in extraterrestrial materials. Its formation, evolution and content in the building blocks ("seeds") for more complex molecules, such as proteins and DNA, are key questions in the field of exobiology. Ultrahigh resolution mass spectrometry is one of the best analytical techniques that can be applied because it provides reliable information on the chemical composition and structure of individual components of complex organic mixtures. Prebiotic organic material is delivered to Earth by meteorites or generated in laboratories in simulation (model) experiments that mimic space or atmospheric conditions. Recent representative examples for ultrahigh resolution mass spectrometry studies using Fourier-transform (FT) mass spectrometers such as Orbitrap and ion cyclotron resonance (ICR) mass spectrometers are shown and discussed in the present article, including: (i) the analysis of organic matter of meteorites; (ii) modeling atmospheric processes in ICR cells; and (iii) the structural analysis of laboratory made tholins that might be present in the atmosphere and surface of Saturn's largest moon, Titan.

  18. The Role of Ultrahigh Resolution Fourier Transform Mass Spectrometry (FT-MS in Astrobiology-Related Research: Analysis of Meteorites and Tholins

    Directory of Open Access Journals (Sweden)

    Árpád Somogyi

    2016-03-01

    Full Text Available It is an important but also a challenging analytical problem to understand the chemical composition and structure of prebiotic organic matter that is present in extraterrestrial materials. Its formation, evolution and content in the building blocks (“seeds” for more complex molecules, such as proteins and DNA, are key questions in the field of exobiology. Ultrahigh resolution mass spectrometry is one of the best analytical techniques that can be applied because it provides reliable information on the chemical composition and structure of individual components of complex organic mixtures. Prebiotic organic material is delivered to Earth by meteorites or generated in laboratories in simulation (model experiments that mimic space or atmospheric conditions. Recent representative examples for ultrahigh resolution mass spectrometry studies using Fourier-transform (FT mass spectrometers such as Orbitrap and ion cyclotron resonance (ICR mass spectrometers are shown and discussed in the present article, including: (i the analysis of organic matter of meteorites; (ii modeling atmospheric processes in ICR cells; and (iii the structural analysis of laboratory made tholins that might be present in the atmosphere and surface of Saturn’s largest moon, Titan.

  19. The Role of Ultrahigh Resolution Fourier Transform Mass Spectrometry (FT-MS) in Astrobiology-Related Research: Analysis of Meteorites and Tholins

    Science.gov (United States)

    Somogyi, Árpád; Thissen, Roland; Orthous-Daunay, Francois-Régis; Vuitton, Véronique

    2016-01-01

    It is an important but also a challenging analytical problem to understand the chemical composition and structure of prebiotic organic matter that is present in extraterrestrial materials. Its formation, evolution and content in the building blocks (“seeds”) for more complex molecules, such as proteins and DNA, are key questions in the field of exobiology. Ultrahigh resolution mass spectrometry is one of the best analytical techniques that can be applied because it provides reliable information on the chemical composition and structure of individual components of complex organic mixtures. Prebiotic organic material is delivered to Earth by meteorites or generated in laboratories in simulation (model) experiments that mimic space or atmospheric conditions. Recent representative examples for ultrahigh resolution mass spectrometry studies using Fourier-transform (FT) mass spectrometers such as Orbitrap and ion cyclotron resonance (ICR) mass spectrometers are shown and discussed in the present article, including: (i) the analysis of organic matter of meteorites; (ii) modeling atmospheric processes in ICR cells; and (iii) the structural analysis of laboratory made tholins that might be present in the atmosphere and surface of Saturn’s largest moon, Titan. PMID:27023520

  20. Applications of direct analysis in real time-mass spectrometry (DART-MS) in Allium chemistry. (Z)-butanethial S-oxide and 1-butenyl thiosulfinates and their S-(E)-1-butenylcysteine S-oxide precursor from Allium siculum.

    Science.gov (United States)

    Kubec, Roman; Cody, Robert B; Dane, A John; Musah, Rabi A; Schraml, Jan; Vattekkatte, Abith; Block, Eric

    2010-01-27

    Lachrymatory (Z)-butanethial S-oxide along with several 1-butenyl thiosulfinates was detected by DART mass spectrometry upon cutting Allium siculum , a popular ornamental Allium species used in some cultures as a spice. (Z)-Butanethial S-oxide isolated from the plant was shown to be identical to a synthetic sample. Its likely precursor, (R(S),R(C),E)-S-(1-butenyl)cysteine S-oxide (homoisoalliin), was isolated from homogenates of A. siculum, and a closely related species Allium tripedale , and fully characterized. Through use of LC-MS, a series of related gamma-glutamyl derivatives were tentatively identified in A. siculum and A. tripedale homogenates, including gamma-glutamyl-(E)-S-(1-butenyl)cysteine and its S-oxide, gamma-glutamyl-S-butylcysteine and its S-oxide, and gamma-glutamyl-S-methylcysteine and its S-oxide. Because compounds containing the 1-butenyl group have not been previously identified in genus Allium species, this work extends the range of known Allium sulfur compounds. The general applicability of DART mass spectrometry in identifying naturally occurring, thermally fragile thial S-oxides and thiosulfinates is illustrated with onion, Allium cepa , as well as a plant from a different genus, Petiveria alliacea .

  1. Screening of pharmaceuticals and illicit drugs in wastewater and surface waters of Spain and Italy by high resolution mass spectrometry using UHPLC-QTOF MS and LC-LTQ-Orbitrap MS.

    Science.gov (United States)

    Bade, Richard; Rousis, Nikolaos I; Bijlsma, Lubertus; Gracia-Lor, Emma; Castiglioni, Sara; Sancho, Juan V; Hernandez, Felix

    2015-12-01

    The existence of pharmaceuticals and illicit drugs (PIDs) in environmental waters has led many analytical chemists to develop screening methods for monitoring purposes. Water samples can contain a huge number of possible contaminants, commonly at low concentrations, which makes their detection and identification problematic. Liquid chromatography coupled with high resolution mass spectrometry (LC-HRMS) has proven itself effective in the screening of environmental contaminants. The present work investigates the use of the most popular HRMS instruments, quadrupole time-of-flight and linear trap quadrupole-Orbitrap, from two different laboratories. A suspect screening for PIDs was carried out on wastewater (influent and effluent) and surface water samples from Castellón, Eastern Spain, and Cremona, Northern Italy, incorporating a database of 107 PIDs (including 220 fragment ions). A comparison between the findings of both instruments and of the samples was made which highlights the advantages and drawbacks of the strategies applied in each case. In total, 28 compounds were detected and/or identified by either/both instruments with irbesartan, valsartan, benzoylecgonine and caffeine being the most commonly found compounds across all samples.

  2. Insight into Identification of Acinetobacter Species by Matrix-Assisted Laser Desorption/Ionization Time of Flight Mass Spectrometry (MALDI-TOF MS) in the Clinical Laboratory

    Science.gov (United States)

    Li, Xiuyuan; Tang, Yanyan; Lu, Xinxin

    2018-04-01

    Currently, the capability of identification for Acinetobacter species using MALDI-TOF MS still remains unclear in clinical laboratories due to certain elusory phenomena. Thus, we conducted this research to evaluate this technique and reveal the causes of misidentification. Briefly, a total of 788 Acinetobacter strains were collected and confirmed at the species level by 16S rDNA and rpoB sequencing, and subsequently compared to the identification by MALDI-TOF MS using direct smear and bacterial extraction pretreatments. Cluster analysis was performed based on the mass spectra and 16S rDNA to reflect the diversity among different species. Eventually, 19 Acinetobacter species were confirmed, including 6 species unavailable in Biotyper 3.0 database. Another novel species was observed, temporarily named A. corallinus. The accuracy of identification for Acinetobacter species using MALDI-TOF MS was 97.08% (765/788), regardless of which pretreatment was applied. The misidentification only occurred on 3 A. parvus strains and 20 strains of species unavailable in the database. The proportions of strains with identification score ≥ 2.000 using direct smear and bacterial extraction pretreatments were 86.04% (678/788) and 95.43% (752/788), χ 2 = 41.336, P clinical samples was deemed reliable. Misidentification occurred occasionally due to the insufficiency of the database rather than sample extraction failure. We suggest gene sequencing should be performed when the identification score is under 2.000 even when using bacterial extraction pretreatment. [Figure not available: see fulltext.

  3. Molecular Characterization and Reactivity of Dissolved Organic Matter by High Resolution Nanospray Ionization Fourier Transform-Ion Cyclotron Resonance Mass Spectrometry (FTICR-MS)

    Science.gov (United States)

    Sleighter, R. L.; Hatcher, S. A.; Hatcher, P. G.

    2006-12-01

    The ultrahigh resolving power of FTICR-MS allows for the intense characterization of dissolved organic matter (DOM). DOM is the largest reactive component of the global carbon cycle, and an improved understanding of its composition is necessary to determine the transport and eventual fate of pollutants. The seasonal and spatial variations in DOM composition are investigated by taking surface water samples from five different sampling sites, four times a year. Water sampling begins at the Dismal Swamp in North Carolina, continues north up the Elizabeth River to the Chesapeake Bay, and concludes approximately ten miles off the coast in the Atlantic Ocean. DOM was extracted from the water samples using C18 extraction disks and were prepared in 50:50 methanol:water. Ammonium hydroxide was added prior to nanospray in order to solubilize the DOM as well as to increase the ionization efficiency. The samples were continuously infused into the Apollo II ion source with an Advion TriVersa NanoMate system of a Bruker 12 Tesla Apex QE FTICR-MS with resolving powers exceeding 400,000. All samples were analyzed in negative ion mode and were externally and internally calibrated prior to data analysis. Our DOM mass spectra consist of a multitude of peaks spanning the range of 200-850 m/z. Complexity is apparent from the detection of up to 20 peaks per nominal mass at nearly every mass throughout that range. A molecular formula calculator generated molecular formula matches from which van Krevelen plots were constructed for characterization purposes. A wide range of molecules were observed each containing oxygen, sulfur and nitrogen functional groups. We utilize the van Krevelen diagram to assist in clustering the molecules according to their functional group compositions. To test the hypothesis that formation of adducts to DOM serve to protect peptides from bacterial degradation, microcosm experiments were performed with a small isotopically enriched peptide, GGGR. This peptide

  4. Quantitative Determination of Perfluorochemicals and Fluorotelomer Alcohols in Plants from Biosolid-Amended Fields using LC/MS/MS and GC/MS

    Science.gov (United States)

    Analytical methods for determining perfluorochemicals (PFCs) and fluorotelomer alcohols (FTOHs) in plants using liquid chromatography/tandem mass spectrometry (LC/MS/MS) and gas chromatography/mass spectrometry (GC/MS) were developed, and applied to quantify a suite of analytes i...

  5. Determination of two progestin metabolites (17α-hydroxypregnanolone and pregnanediol) and different classes of steroids (androgens, estrogens, corticosteroids, progestins) in rivers and wastewaters by high-performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS).

    Science.gov (United States)

    Zhang, Kun; Fent, Karl

    2018-01-01

    A highly sensitive and robust method was developed for routine analysis of two progestin metabolites, 17α-hydroxypregnanolone (17OH-Δ5P) and pregnanediol (PD), and 31 other natural and synthetic steroids and related metabolites (estrogens, androgens, corticosteroids, progestins) in river water, as well as influents and effluents of municipal wastewater treatment plants (WWTP) using HPLC-MS/MS combined with solid-phase extraction. For the various matrixes considered, the optimized method showed satisfactory performance with recoveries of 70-120% for most of target steroids. The method detection limits (MDLs) ranged from 0.01 to 3ng/L for river water, 0.02 to 10ng/L for WWTP effluents, and 0.1 to 40ng/L for influents with good linearity and reproducibility. The developed method was successfully applied for the analysis of steroids in rivers and WWTP influent and effluents. WWTP influents concentrations of 17OH-Δ5P and PD were 51-256ng/L and up to 400ng/L, respectively, along with androstenedione (concentration range: 38-220ng/L), testosterone (11-26ng/L), estrone (2.3-37ng/L), 17β-estradiol (N.D.-8.7ng/L), 17α-hydroxyprogesterone (N.D.-66ng/L), medroxyprogesterone acetate (N.D.-5.3ng/L), and progesterone (2.0-22ng/L), while only androstenedione (ADD), estrone (E1), and estriol (E3) were detected in effluent with concentrations ranging up to 1.7ng/L, 0.90ng/L and 0.8ng/L, respectively. In river water samples, only ADD and E1 were detected with concentrations up to 1.0ng/L and 0.91ng/L. Our procedure represents the first method for analyzing 17OH-Δ5P and PD in environmental samples along with a large series of steroids. Copyright © 2017 Elsevier B.V. All rights reserved.

  6. Validation of an analytical method for nitrous oxide (N2O) laughing gas by headspace gas chromatography coupled to mass spectrometry (HS-GC-MS): forensic application to a lethal intoxication.

    Science.gov (United States)

    Giuliani, N; Beyer, J; Augsburger, M; Varlet, V

    2015-03-01

    Drug abuse is a widespread problem affecting both teenagers and adults. Nitrous oxide is becoming increasingly popular as an inhalation drug, causing harmful neurological and hematological effects. Some gas chromatography-mass spectrometry (GC-MS) methods for nitrous oxide measurement have been previously described. The main drawbacks of these methods include a lack of sensitivity for forensic applications; including an inability to quantitatively determine the concentration of gas present. The following study provides a validated method using HS-GC-MS which incorporates hydrogen sulfide as a suitable internal standard allowing the quantification of nitrous oxide. Upon analysis, sample and internal standard have similar retention times and are eluted quickly from the molecular sieve 5Å PLOT capillary column and the Porabond Q column therefore providing rapid data collection whilst preserving well defined peaks. After validation, the method has been applied to a real case of N2O intoxication indicating concentrations in a mono-intoxication. Copyright © 2015 Elsevier B.V. All rights reserved.

  7. Gas Chromatography Time-Of-Flight Mass Spectrometry (GC-TOF-MS)-Based Metabolomics for Comparison of Caffeinated and Decaffeinated Coffee and Its Implications for Alzheimer’s Disease

    Science.gov (United States)

    Chang, Kai Lun; Ho, Paul C.

    2014-01-01

    Findings from epidemiology, preclinical and clinical studies indicate that consumption of coffee could have beneficial effects against dementia and Alzheimer’s disease (AD). The benefits appear to come from caffeinated coffee, but not decaffeinated coffee or pure caffeine itself. Therefore, the objective of this study was to use metabolomics approach to delineate the discriminant metabolites between caffeinated and decaffeinated coffee, which could have contributed to the observed therapeutic benefits. Gas chromatography time-of-flight mass spectrometry (GC-TOF-MS)-based metabolomics approach was employed to characterize the metabolic differences between caffeinated and decaffeinated coffee. Orthogonal partial least squares discriminant analysis (OPLS-DA) showed distinct separation between the two types of coffee (cumulative Q2 = 0.998). A total of 69 discriminant metabolites were identified based on the OPLS-DA model, with 37 and 32 metabolites detected to be higher in caffeinated and decaffeinated coffee, respectively. These metabolites include several benzoate and cinnamate-derived phenolic compounds, organic acids, sugar, fatty acids, and amino acids. Our study successfully established GC-TOF-MS based metabolomics approach as a highly robust tool in discriminant analysis between caffeinated and decaffeinated coffee samples. Discriminant metabolites identified in this study are biologically relevant and provide valuable insights into therapeutic research of coffee against AD. Our data also hint at possible involvement of gut microbial metabolism to enhance therapeutic potential of coffee components, which represents an interesting area for future research. PMID:25098597

  8. Results of an interlaboratory method performance study for the size determination and quantification of silver nanoparticles in chicken meat by single-particle inductively coupled plasma mass spectrometry (sp-ICP-MS).

    Science.gov (United States)

    Weigel, Stefan; Peters, Ruud; Loeschner, Katrin; Grombe, Ringo; Linsinger, Thomas P J

    2017-08-01

    Single-particle inductively coupled plasma mass spectrometry (sp-ICP-MS) promises fast and selective determination of nanoparticle size and number concentrations. While several studies on practical applications have been published, data on formal, especially interlaboratory validation of sp-ICP-MS, is sparse. An international interlaboratory study was organized to determine repeatability and reproducibility of the determination of the median particle size and particle number concentration of Ag nanoparticles (AgNPs) in chicken meat. Ten laboratories from the European Union, the USA, and Canada determined particle size and particle number concentration of two chicken meat homogenates spiked with polyvinylpyrrolidone (PVP)-stabilized AgNPs. For the determination of the median particle diameter, repeatability standard deviations of 2 and 5% were determined, and reproducibility standard deviations were 15 and 25%, respectively. The equivalent median diameter itself was approximately 60% larger than the diameter of the particles in the spiking solution. Determination of the particle number concentration was significantly less precise, with repeatability standard deviations of 7 and 18% and reproducibility standard deviations of 70 and 90%.

  9. Determination of volatile organic compounds (VOCs) using tedlar bag/solid-phase microextraction/gas chromatography/mass spectrometry (SPME/GC/MS) in ambient and workplace air

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Jae Hwan; Lee, Dai Woon [Yonsei Univ., Seoul (Korea, Republic of); Hwang, Seung Man; Heo, Gwi Suk [Korea Research Institute of Standards and Science, Taejon (Korea, Republic of)

    2002-03-01

    SPME techniques have proven to be very useful tools in the analysis of wide VOCs in the air. In this study, we estimated VOCs in ambient and workplace air using a Tedlar ba/SPME/GC/MS system. The calibration curve was set to be linear over the range of 1-30 ppbv. The detection limits ranged from 10 pptv 0.93 ppbv for all VOCs. Reproducibility of TO-14 target gas mixtures by SPME/GC/MS averaged at 8.8 R.S.D (%). Air toxic VOCs (hazardous air pollutants, HAPs) containing a total of forty halohydrocarbons, aromatics, and haloaro-matic carbons could be analyzed with significant accuracy, detection limit and linearity at low ppbv level. Only reactive VOCs with low molecular weight, such as chloromethane, vinylchloride, ethylchloride and 1,2-dichloro-ethane, yielded relatively poor results using this technique. In ambient air samples, ten VOCs were identified and quantified after external calibration. VOC concentration in ambient and workplace air ranged from 0.04 to 1.85 ppbv. The overall process was successfully applied to identify and quantify VOCs in ambient/workplace air.

  10. Biomarker- and similarity coefficient-based approaches to bacterial mixture characterization using matrix-assisted laser desorption ionization time-of-flight mass spectrometry (MALDI-TOF MS).

    Science.gov (United States)

    Zhang, Lin; Smart, Sonja; Sandrin, Todd R

    2015-11-05

    MALDI-TOF MS profiling has been shown to be a rapid and reliable method to characterize pure cultures of bacteria. Currently, there is keen interest in using this technique to identify bacteria in mixtures. Promising results have been reported with two- or three-isolate model systems using biomarker-based approaches. In this work, we applied MALDI-TOF MS-based methods to a more complex model mixture containing six bacteria. We employed: 1) a biomarker-based approach that has previously been shown to be useful in identification of individual bacteria in pure cultures and simple mixtures and 2) a similarity coefficient-based approach that is routinely and nearly exclusively applied to identification of individual bacteria in pure cultures. Both strategies were developed and evaluated using blind-coded mixtures. With regard to the biomarker-based approach, results showed that most peaks in mixture spectra could be assigned to those found in spectra of each component bacterium; however, peaks shared by two isolates as well as peaks that could not be assigned to any individual component isolate were observed. For two-isolate blind-coded samples, bacteria were correctly identified using both similarity coefficient- and biomarker-based strategies, while for blind-coded samples containing more than two isolates, bacteria were more effectively identified using a biomarker-based strategy.

  11. Determination of volatile organic compounds (VOCs) using tedlar bag/solid-phase microextraction/gas chromatography/mass spectrometry (SPME/GC/MS) in ambient and workplace air

    International Nuclear Information System (INIS)

    Lee, Jae Hwan; Lee, Dai Woon; Hwang, Seung Man; Heo, Gwi Suk

    2002-01-01

    SPME techniques have proven to be very useful tools in the analysis of wide VOCs in the air. In this study, we estimated VOCs in ambient and workplace air using a Tedlar ba/SPME/GC/MS system. The calibration curve was set to be linear over the range of 1-30 ppbv. The detection limits ranged from 10 pptv 0.93 ppbv for all VOCs. Reproducibility of TO-14 target gas mixtures by SPME/GC/MS averaged at 8.8 R.S.D (%). Air toxic VOCs (hazardous air pollutants, HAPs) containing a total of forty halohydrocarbons, aromatics, and haloaro-matic carbons could be analyzed with significant accuracy, detection limit and linearity at low ppbv level. Only reactive VOCs with low molecular weight, such as chloromethane, vinylchloride, ethylchloride and 1,2-dichloro-ethane, yielded relatively poor results using this technique. In ambient air samples, ten VOCs were identified and quantified after external calibration. VOC concentration in ambient and workplace air ranged from 0.04 to 1.85 ppbv. The overall process was successfully applied to identify and quantify VOCs in ambient/workplace air

  12. Determination of Inter-leaf Translocated Free Glyphosate in Arabidopsis thaliana using Liquid Chromatography Tandem Mass Spectrometry (LCMS/MS) after Derivatization with Fluorenylmethyloxycarbonyl Chloride (FMOC-Cl)

    KAUST Repository

    Raji, Misjudeen

    2014-02-03

    Glyphosate is a broad-spectrum herbicide widely used for eliminating weeds in crop fields. Its mode of action is believed to be via translocation from the source to the sink tissues where it then interferes with the activities of 5-enol-pyruvylshikimate-3-phosphate synthase (EPSPS). In this study, the translocation of glyphosate in the leaves of Arabidopsis thaliana was investigated using an HPLC-MS/MS method following derivatization of the secondary amino group in the analyte using N-(9-fluorenylmethoxycarbonyloxy) chloride. To eliminate the errant precipitation that occurred when the reagent and the analyte are mixed, optimization of this method was required. The method linearity has a correlation coefficient higher than 0.99 over the concentration range of 0.005-2 μM. The limits of detection and quantitation were estimated to be 0.002 μM and 0.008 μM respectively. The repeatability of the method (as%R.S.D) ranged from 10% to 13%. The presented method was employed for the determination of free glyphosate in young untreated leaves of the specimen plants after treating a single leaf and allowing it to stand for 12 hours.

  13. Determination of Inter-leaf Translocated Free Glyphosate in Arabidopsis thaliana using Liquid Chromatography Tandem Mass Spectrometry (LCMS/MS) after Derivatization with Fluorenylmethyloxycarbonyl Chloride (FMOC-Cl)

    KAUST Repository

    Raji, Misjudeen; Gehring, Christoph A; Sharkhuu, Altanbadralt; Amad, Maan H.; Merzaban, Jasmeen

    2014-01-01

    Glyphosate is a broad-spectrum herbicide widely used for eliminating weeds in crop fields. Its mode of action is believed to be via translocation from the source to the sink tissues where it then interferes with the activities of 5-enol-pyruvylshikimate-3-phosphate synthase (EPSPS). In this study, the translocation of glyphosate in the leaves of Arabidopsis thaliana was investigated using an HPLC-MS/MS method following derivatization of the secondary amino group in the analyte using N-(9-fluorenylmethoxycarbonyloxy) chloride. To eliminate the errant precipitation that occurred when the reagent and the analyte are mixed, optimization of this method was required. The method linearity has a correlation coefficient higher than 0.99 over the concentration range of 0.005-2 μM. The limits of detection and quantitation were estimated to be 0.002 μM and 0.008 μM respectively. The repeatability of the method (as%R.S.D) ranged from 10% to 13%. The presented method was employed for the determination of free glyphosate in young untreated leaves of the specimen plants after treating a single leaf and allowing it to stand for 12 hours.

  14. Investigation of Volatiles Emitted from Freshly Cut Onions (Allium cepa L. by Real Time Proton-Transfer Reaction-Mass Spectrometry (PTR-MS

    Directory of Open Access Journals (Sweden)

    Mette Marie Løkke

    2012-11-01

    Full Text Available Volatile organic compounds (VOCs in cut onions (Allium cepa L. were continuously measured by PTR-MS during the first 120 min after cutting. The headspace composition changed rapidly due to the very reactive volatile sulfurous compounds emitted from onion tissue after cell disruption. Mass spectral signals corresponding to propanethial S-oxide (the lachrymatory factor and breakdown products of this compound dominated 0–10 min after cutting. Subsequently, propanethiol and dipropyl disulfide predominantly appeared, together with traces of thiosulfinates. The concentrations of these compounds reached a maximum at 60 min after cutting. Propanethiol was present in highest concentrations and had an odor activity value 20 times higher than dipropyl disulfide. Thus, propanethiol is suggested to be the main source of the characteristic onion odor. Monitoring the rapid changes of VOCs in the headspace of cut onion necessitates a high time resolution, and PTR-MS is demonstrated to be a very suitable method for monitoring the headspace of freshly cut onions directly after cutting without extraction or pre-concentration.

  15. Exploring Biosignatures Associated with Thenardite by Geomatrix-Assisted Laser Desorption/Ionization Fourier Transform Ion Cyclotron Resonance Mass Spectrometry (GALDI-FTICR-MS)

    Energy Technology Data Exchange (ETDEWEB)

    C. Doc Richardson; Nancy W. Hinman; Timothy R. McJunkin; J. Michelle Kotler; Jill R. Scott

    2008-10-01

    Geomatrix-assisted laser desorption/ionization (GALDI) in conjunction with a Fourier transform ion cyclotron resonance mass spectrometer (FTICR-MS) has been employed to determine how effectively bio/organic molecules associated with the mineral thenardite (Na2SO4) can be detected. GALDI is based on the ability of the mineral host to assist desorption and ionization of bio/organic molecules without additional sample preparation. When glycine was mixed with thenardite, glycine was deprotonated to produce C2H4NO-2 at m/z 74.025. The combination of stearic acid with thenardite produced a complex cluster ion at m/z 390.258 in the negative mode, which was assigned a composition ofC18H39O7Na-. Anatural sample of thenardite from Searles Lake in California also produced a peak at m/z 390.260. The bio/organic signatures in both the laboratory-based and natural samples were heterogeneously dispersed as revealed by chemical imaging. The detection limits for the stearic acid and thenardite combination were estimated to be 3 parts per trillion or~7 zeptomoles (10-21) per laser spot. Attempts to improve the signal-to-noise ratio by co-adding FTICR-MS data predetermined to contain the biosignatures of interest revealed problems due to a lack of phase coherence between data sets.

  16. 直接实时分析质谱超速分析在药品监管中的应用%Ultra Speed Direct Analysis in Real Time Mass Spectrometry(DART-MS)for Drug Administration

    Institute of Scientific and Technical Information of China (English)

    王铁松; 张喆; 赵明; 车宝泉; 高青; 王威

    2011-01-01

    目的 建立直接实时分析质谱(DART-MS)超速分析方法应用于药品监管检验工作.方法 DART-MS将实时直接分析离子源(DART)与离子阱质谱联用,离子源放电电压为4kV,载气为氦气,流速为6L· min(-1),温度为400℃.在不进行样品色谱分离的前提下,直接分析被测物质或其溶液.结果 DART-MS与液质联用相比检定效率提高近50倍,对西地那非、米诺地尔等已知物质可在20s内检测出,对未知衍生物可在4 min内完成其多级质谱研究,对传统液相色谱法难以分析的辅料如混合脂肪酸甘油酯等也能准确分析.结论 DART-MS样品处理简单,方法准确速度快,能广泛应用于非法添加、药物污染、制剂辅料成分的快速检定,开创了药品监管的新方法,能有效提高对突发安全事件的反应能力.%OBJECTIVE To establish an ultra speed direct analysis in real time (DART)-ion trap mass spectrometry method for screening of shampoo and herbal remedies for the presence of illegal additives. METHODS The DART temperature was 400 ℃, the helium flow rate was 6 L · min-1 and the mass cone voltage was 4 kV. The solution was directly screened using a 12-DIP sampler. RESULTS The speed of DART-MS was 50 times faster than that of LC-MS for identifying the additives including minoxidil,sildenafil,and mixed glycerides. CONCLUSION Each additive studied was rapidly identified within 20 seconds by DART-MS/MS, sugggesting this technique can be used for drug administration. However,its sensitivity and quantitation still requires further study and improvement.

  17. Elemental analysis of soils using laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS) and laser-induced breakdown spectroscopy (LIBS) with multivariate discrimination: tape mounting as an alternative to pellets for small forensic transfer specimens.

    Science.gov (United States)

    Jantzi, Sarah C; Almirall, José R

    2014-01-01

    Elemental analysis of soil is a useful application of both laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS) and laser-induced breakdown spectroscopy (LIBS) in geological, agricultural, environmental, archeological, planetary, and forensic sciences. In forensic science, the question to be answered is often whether soil specimens found on objects (e.g., shoes, tires, or tools) originated from the crime scene or other location of interest. Elemental analysis of the soil from the object and the locations of interest results in a characteristic elemental profile of each specimen, consisting of the amount of each element present. Because multiple elements are measured, multivariate statistics can be used to compare the elemental profiles in order to determine whether the specimen from the object is similar to one of the locations of interest. Previous work involved milling and pressing 0.5 g of soil into pellets before analysis using LA-ICP-MS and LIBS. However, forensic examiners prefer techniques that require smaller samples, are less time consuming, and are less destructive, allowing for future analysis by other techniques. An alternative sample introduction method was developed to meet these needs while still providing quantitative results suitable for multivariate comparisons. The tape-mounting method involved deposition of a thin layer of soil onto double-sided adhesive tape. A comparison of tape-mounting and pellet method performance is reported for both LA-ICP-MS and LIBS. Calibration standards and reference materials, prepared using the tape method, were analyzed by LA-ICP-MS and LIBS. As with the pellet method, linear calibration curves were achieved with the tape method, as well as good precision and low bias. Soil specimens from Miami-Dade County were prepared by both the pellet and tape methods and analyzed by LA-ICP-MS and LIBS. Principal components analysis and linear discriminant analysis were applied to the multivariate data

  18. Identification of known chemicals and their metabolites from Alpinia oxyphylla fruit extract in rat plasma using liquid chromatography/tandem mass spectrometry (LC-MS/MS) with selected reaction monitoring.

    Science.gov (United States)

    Chen, Feng; Li, Hai-Long; Tan, Yin-Feng; Li, Yong-Hui; Lai, Wei-Yong; Guan, Wei-Wei; Zhang, Jun-Qing; Zhao, Yuan-Sheng; Qin, Zhen-Miao

    2014-08-01

    Alpinia oxyphylla (Yizhi) capsularfruits are commonly used in traditional medicine. Pharmacological studies have demonstrated that A. oxyphylla capsularfruits have some beneficial roles. Besides volatile oil, sesquiterpenes, diarylheptanoids and flavonoids are main bioactive constituents occurring in the Yizhi capsularfruits. The representative constituents include tectochrysin, izalpinin, chrysin, apigenin-4',7-dimethylether, kaempferide, yakuchinone A, yakuchinone B, oxyphyllacinol and nootkatone. Their content levels in the fruit and its pharmaceutical preparations have been reported by our group. The nine phytochemicals are also the major components present in the Yizhi alcoholic extracts, which have anti-diarrheal activities. However, the fates of these constituents in the body after oral or intravenous administration remain largely unknown. In the present study, we focus on these phytochemicals albeit other concomitant compounds. The chemicals and their metabolites in rat plasma were identified using liquid chromatography/tandem mass spectrometry with selected reaction monitoring mode after orally administered Yizhi extract to rats. Rat plasma samples were treated by methanol precipitation, acidic or enzymatic hydrolysis. This target analysis study revealed that: (1) low or trace plasma levels of parent chemicals were measured after p.o. administration of Yizhi extract, Suoquan capsules and pills to rats; (2) flavonoids and diarylheptanoids formed mainly monoglucuronide metabolites; however, diglucuronide metabolites for chrysin, izalpinin and kaempferide were also detected; (3) metabolic reduction of Yizhi diarylheptanoids occurred in rats. Yakuchinone B was reduced to yakuchinone A and then to oxyphyllacinol in a stepwise manner and subsequently glucuronidated by UDP-glucuronosyl transferase. Further research is needed to characterize the UDP-glucuronosyl transferase and reductase involved in the biotransformation of Yizhi chemicals. Copyright © 2014

  19. Solid phase extraction for analysis of biogenic carbonates by electrothermal vaporization inductively coupled plasma mass spectrometry (ETV-ICP-MS): an investigation of rare earth element signatures in otolith microchemistry

    International Nuclear Information System (INIS)

    Arslan, Zikri; Paulson, Anthony J.

    2003-01-01

    Uptake of trace elements into fish otoliths is governed by several factors such as life histories and environment in addition to stock and species differences. In an attempt to elucidate the elemental signatures of rare earth elements (REEs) in otoliths, a solid phase extraction (SPE) protocol was used in combination with electrothermal vaporization (ETV) as a sample introduction procedure for the determinations by inductively coupled plasma quadrupole mass spectrometry (ICP-MS). Effects of various parameters, such as carrier gas flow rate, atomization temperature and chemical modification, were examined for optimization of the conditions by ETV-ICP-MS. Atomization was achieved at 2800 deg. C. Lower temperatures (i.e. 2600 deg. C) resulted in severe memory problems due to incomplete atomization. Palladium was used as a chemical modifier. It was found that an increase in Pd concentration up to 0.5 μg in the injection volume (70 μl) led up to four-fold enhancement in the integrated signals. This phenomenon is attributed to the carrier effect of Pd rather than the stabilization since no significant losses were observed for high temperature drying around 700 deg. C even in the absence of Pd. Preconcentration was performed on-line at pH 5 by using a mini-column of Toyopearl AF-Chelate 650M chelating resin, which also eliminated the calcium matrix of otolith solutions. After preconcentration of 6.4 ml of solution, the concentrate was collected in 0.65 ml of 0.5% (v/v) HNO 3 in autosampler cups, and then analyzed by ETV-ICP-MS. The method was validated with the analysis of a fish otolith certified reference material (CRM) of emperor snapper, and then applied to samples. Results obtained from otoliths of fish captured in the same habitat indicated that otolith rare earth element concentrations are more dependent on environmental conditions of the habitat than on species differences

  20. A Metabolomic Approach Applied to a Liquid Chromatography Coupled to High-Resolution Tandem Mass Spectrometry Method (HPLC-ESI-HRMS/MS): Towards the Comprehensive Evaluation of the Chemical Composition of Cannabis Medicinal Extracts.

    Science.gov (United States)

    Citti, Cinzia; Battisti, Umberto Maria; Braghiroli, Daniela; Ciccarella, Giuseppe; Schmid, Martin; Vandelli, Maria Angela; Cannazza, Giuseppe

    2018-03-01

    Cannabis sativa L. is a powerful medicinal plant and its use has recently increased for the treatment of several pathologies. Nonetheless, side effects, like dizziness and hallucinations, and long-term effects concerning memory and cognition, can occur. Most alarming is the lack of a standardised procedure to extract medicinal cannabis. Indeed, each galenical preparation has an unknown chemical composition in terms of cannabinoids and other active principles that depends on the extraction procedure. This study aims to highlight the main differences in the chemical composition of Bediol® extracts when the extraction is carried out with either ethyl alcohol or olive oil for various times (0, 60, 120 and 180 min for ethyl alcohol, and 0, 60, 90 and 120 min for olive oil). Cannabis medicinal extracts (CMEs) were analysed by liquid chromatography coupled to high-resolution tandem mass spectrometry (LC-MS/MS) using an untargeted metabolomics approach. The data sets were processed by unsupervised multivariate analysis. Our results suggested that the main difference lies in the ratio of acid to decarboxylated cannabinoids, which dramatically influences the pharmacological activity of CMEs. Minor cannabinoids, alkaloids, and amino acids contributing to this difference are also discussed. The main cannabinoids were quantified in each extract applying a recently validated LC-MS and LC-UV method. Notwithstanding the use of a standardised starting plant material, great changes are caused by different extraction procedures. The metabolomics approach is a useful tool for the evaluation of the chemical composition of cannabis extracts. Copyright © 2017 John Wiley & Sons, Ltd. Copyright © 2017 John Wiley & Sons, Ltd.

  1. Ribosomal subunit protein typing using matrix-assisted laser desorption ionization time-of-flight mass spectrometry (MALDI-TOF MS) for the identification and discrimination of Aspergillus species.

    Science.gov (United States)

    Nakamura, Sayaka; Sato, Hiroaki; Tanaka, Reiko; Kusuya, Yoko; Takahashi, Hiroki; Yaguchi, Takashi

    2017-04-26

    Accurate identification of Aspergillus species is a very important subject. Mass spectral fingerprinting using matrix-assisted laser desorption ionization time-of-flight mass spectrometry (MALDI-TOF MS) is generally employed for the rapid identification of fungal isolates. However, the results are based on simple mass spectral pattern-matching, with no peak assignment and no taxonomic input. We propose here a ribosomal subunit protein (RSP) typing technique using MALDI-TOF MS for the identification and discrimination of Aspergillus species. The results are concluded to be phylogenetic in that they reflect the molecular evolution of housekeeping RSPs. The amino acid sequences of RSPs of genome-sequenced strains of Aspergillus species were first verified and compared to compile a reliable biomarker list for the identification of Aspergillus species. In this process, we revealed that many amino acid sequences of RSPs (about 10-60%, depending on strain) registered in the public protein databases needed to be corrected or newly added. The verified RSPs were allocated to RSP types based on their mass. Peak assignments of RSPs of each sample strain as observed by MALDI-TOF MS were then performed to set RSP type profiles, which were then further processed by means of cluster analysis. The resulting dendrogram based on RSP types showed a relatively good concordance with the tree based on β-tubulin gene sequences. RSP typing was able to further discriminate the strains belonging to Aspergillus section Fumigati. The RSP typing method could be applied to identify Aspergillus species, even for species within section Fumigati. The discrimination power of RSP typing appears to be comparable to conventional β-tubulin gene analysis. This method would therefore be suitable for species identification and discrimination at the strain to species level. Because RSP typing can characterize the strains within section Fumigati, this method has potential as a powerful and reliable tool in

  2. Serum amyloid beta peptides in patients with dementia and age-matched non-demented controls as detected by surface-enhanced laser desorption ionisation-time of flight mass spectrometry (SELDI-TOF MS).

    Science.gov (United States)

    Frankfort, Suzanne V; van Campen, Jos P C M; Tulner, Linda R; Beijnen, Jos H

    2008-09-01

    By using surface enhanced laser desorption/ionisation- time of flight mass spectrometry (SELDI-TOF MS) an amyloid beta (Abeta) profile was shown in cerebrospinal fluid (CSF) of patients with dementia. To investigate the Abeta-profile in serum with SELDI-TOF MS, to evaluate if this profile resembles CSF profiles and to investigate the correlation between intensity of Abeta-peptide-peaks in serum and clinical, demographical and genetic variables. Duplicate profiling of Abeta by an SELDI-TOF MS immunocapture assay was performed in 106 patients, suffering from Alzheimer's Disease or Vascular Dementia and age-matched non-demented control patients. Linear regression analyses were performed to investigate the intensities of four selected Abeta peaks as dependent variables in relation to the independent clinical, demographic or genetic variables. Abeta37, Abeta38 and Abeta40 were found among additional unidentified Abeta peptides, with the most pronounced Abeta peak at a molecular mass of 7752. This profile partly resembled the CSF profile. The clinical diagnosis was not a predictive independent variable, however ABCB1 genotypes C1236T, G2677T/A, age and creatinine level showed to be related to Abeta peak intensities in multivariate analyses. We found an Abeta profile in serum that partly resembled the CSF profile in demented patients. Age, creatinine levels, presence of the APOE epsilon4 allele and ABCB1 genotypes (C1236T and G2677T/A) were correlated with the Abeta serum profile. The role of P-gp as an Abeta transporter and the role of ABCB1 genotypes deserves further research. The investigated serum Abeta profile is probably not useful in the diagnosis of dementia.

  3. An Automated Sample Preparation Instrument to Accelerate Positive Blood Cultures Microbial Identification by MALDI-TOF Mass Spectrometry (Vitek®MS

    Directory of Open Access Journals (Sweden)

    Patrick Broyer

    2018-05-01

    Full Text Available Sepsis is the leading cause of death among patients in intensive care units (ICUs requiring an early diagnosis to introduce efficient therapeutic intervention. Rapid identification (ID of a causative pathogen is key to guide directed antimicrobial selection and was recently shown to reduce hospitalization length in ICUs. Direct processing of positive blood cultures by MALDI-TOF MS technology is one of the several currently available tools used to generate rapid microbial ID. However, all recently published protocols are still manual and time consuming, requiring dedicated technician availability and specific strategies for batch processing. We present here a new prototype instrument for automated preparation of Vitek®MS slides directly from positive blood culture broth based on an “all-in-one” extraction strip. This bench top instrument was evaluated on 111 and 22 organisms processed using artificially inoculated blood culture bottles in the BacT/ALERT® 3D (SA/SN blood culture bottles or the BacT/ALERT VirtuoTM system (FA/FN Plus bottles, respectively. Overall, this new preparation station provided reliable and accurate Vitek MS species-level identification of 87% (Gram-negative bacteria = 85%, Gram-positive bacteria = 88%, and yeast = 100% when used with BacT/ALERT® 3D and of 84% (Gram-negative bacteria = 86%, Gram-positive bacteria = 86%, and yeast = 75% with Virtuo® instruments, respectively. The prototype was then evaluated in a clinical microbiology laboratory on 102 clinical blood culture bottles and compared to routine laboratory ID procedures. Overall, the correlation of ID on monomicrobial bottles was 83% (Gram-negative bacteria = 89%, Gram-positive bacteria = 79%, and yeast = 78%, demonstrating roughly equivalent performance between manual and automatized extraction methods. This prototype instrument exhibited a high level of performance regardless of bottle type or BacT/ALERT system. Furthermore, blood culture workflow could

  4. Molecular analysis of intact preen waxes of Calidris Canutus (Aves: Scolopacidae) by GC/MS and GC/MS/MS

    NARCIS (Netherlands)

    Sinninghe Damsté, J.S.; Dekker, M.H.A.; Piersma, T.

    2000-01-01

    The intact preen wax esters of the red knot Calidris canutus were studied with gas chromatography/mass spectrometry (GC/MS) and GC/MS/MS. In this latter technique, transitions from the molecular ion to fragment ions representing the fatty acid moiety of the wax esters were measured, providing

  5. Determination of taxonomic status of chinese species of the genus clematis by using high performance liquid chromatography-mass spectrometry (HPLC-MS) technique

    International Nuclear Information System (INIS)

    Ishtiaq, M.; Ahmed, H.

    2010-01-01

    A comparative taxonomic study using chemometric and numerical taxonomic approaches on 15 populations of 12 species of major taxa of the genus Clematis, belonging to sections, Rectae, Clematis, Meclatis, Tubulosae and Viorna were analyzed by HPLC coupled with diode array detector and ESI-MS. The chemo diversity profile of saponins proved to be useful taxonomic markers for the genus and results are presented in pheno grams. The compound 'Huzhangoside D' was the most abundant in analyzed species of the genus. Numerical taxonomic study was also conducted based on phylogenetically informative characters which corroborated with chemical fingerprinting findings. The significance of chemical markers in taxonomic study as well as their correlation between morphology and chemical compound profile is also debated with its significant role in botanic drugs identification. (author)

  6. Determination of lead by hydride generation inductively coupled plasma mass spectrometry (HG-ICP-MS): On-line generation of plumbane using potassium hexacyanomanganate(III)

    Energy Technology Data Exchange (ETDEWEB)

    Yilmaz, Vedat [Jackson State University, Department of Chemistry and Biochemistry, Jackson, MS 39217 (United States); Erciyes University, Faculty of Pharmacy, Department of Analytical Chemistry, 38039 Kayseri (Turkey); Arslan, Zikri, E-mail: zikri.arslan@jsums.edu [Jackson State University, Department of Chemistry and Biochemistry, Jackson, MS 39217 (United States); Rose, LaKeysha [Jackson State University, Department of Chemistry and Biochemistry, Jackson, MS 39217 (United States)

    2013-01-25

    Highlights: Black-Right-Pointing-Pointer Potassium hexacyanomanganate(III), (K{sub 3}Mn(CN){sub 6}, was utilized first time for hydride generation (HG). Black-Right-Pointing-Pointer Hexacyanomanganate(III) promoted generation of lead hydride (PbH{sub 4}) remarkably. Black-Right-Pointing-Pointer The HG method using K{sub 3}Mn(CN){sub 6} enhanced sensitivity by at least 40-fold. Black-Right-Pointing-Pointer The method detection limits for Pb were as low as 8 ng L{sup -1} by ICP-MS. Black-Right-Pointing-Pointer The method is highly suitable for quantitative determination of Pb in various samples and salt matrices by ICP-MS. - Abstract: A hydride generation (HG) procedure has been described for determination of Pb by ICP-MS using potassium hexacyanomanganate(III), K{sub 3}Mn(CN){sub 6}, as an additive to facilitate the generation of plumbane (PbH{sub 4}). Potassium hexacyanomanganate(III) was prepared in acidic medium as it was unstable in water. The stability of hexacyanomanganate(III) was examined in dilute solutions of HCl, HNO{sub 3} and H{sub 2}SO{sub 4}. The solutions prepared in 1% v/v H{sub 2}SO{sub 4} were found to be stable for over a period of 24 h. The least suitable medium was 1% v/v HNO{sub 3}. For generation of plumbane, acidic hexacyanomanganate(III) and sample solutions were mixed on-line along a 5-cm long tygon tubing (1.14 mm i.d.) and then reacted with 2% m/v sodium borohydride (NaBH{sub 4}). A concentration of 0.5% m/v K{sub 3}Mn(CN){sub 6} facilitated the generation of PbH{sub 4} remarkably. In comparison to H{sub 2}SO{sub 4}, HCl provided broader working range for which optimum concentration was 1% v/v. No significant interferences were noted from transition metals and hydride forming elements, up to 0.5 {mu}g mL{sup -1} levels, except Cu which depressed the signals severely. The depressive effects in the presence of 0.1 {mu}g mL{sup -1} Cu were alleviated by increasing the concentration of K{sub 3}Mn(CN){sub 6} to 2% m/v. Under these conditions

  7. Investigation of metallodrug-protein interactions by size-exclusion chromatography coupled with inductively coupled plasma mass spectrometry (ICP-MS)

    International Nuclear Information System (INIS)

    Szpunar, J.; Makarov, A.; Pieper, T.; Keppler, B.K.; Lobinski, R.

    1999-01-01

    The coupling of size-exclusion HPLC with ICP-MS was developed for the studies of the kinetics of metallodrug binding to human serum proteins. Two platinum- and three ruthenium-based drugs were investigated. Various SEC columns (of different lengths and with different packings) were compared for the separation of the protein-bound and unbound fractions of a metallodrug prior to on-line detection of the metal (Ru or Pt). The approach developed offers considerable advantages over the methods based on ultrafiltration followed by the off-line metal determination in terms of speed, simplicity, precision and selectivity regarding the molecular weight of the complexes involved. (Copyright (c) 1999 Elsevier Science B.V., Amsterdam. All rights reserved.)

  8. Simultaneous measurement of {sup 239}Pu, {sup 240}Pu, {sup 241}Pu, and {sup 242}Pu by high resolution inductively coupled plasma mass spectrometer (HR ICP-MS) in marine sediments; Mesure des isotopes du plutonium des sediments marins par spectrometrie de masse a plasma couple inductivement haute resolution (HR ICP-MS)

    Energy Technology Data Exchange (ETDEWEB)

    Bruneau, F

    1999-07-01

    Transuranics elements are of particular interest in radioecological studies because of their radiotoxicity and their potential use to decipher source fingerprints and transport processes. The simultaneous measurement of {sup 239}Pu, {sup 240}Pu, {sup 241}Pu, and {sup 242}Pu in environmental samples requires a specific chemical procedure. This work deals with an analytical procedure which yields a very high grade of purification of Pu suitable for ultra low level detection by HR ICP-MS, from marine sediments. After the elimination of major elements (Fe, Al, Mg...) by a first chromatographic separation, a new device of purification by solvent extraction and concentration by a second chromatographic separation is used to obtain a concentrated and high purified solution of plutonium. The chemical procedure have been validated on IAEA certified sediment samples and on sediment samples collected in the roads of Cherbourg which had been previously analysed by other techniques (a spectrometry and thermo-ionisation mass spectrometer). (author)

  9. Detection of changes in fuel quality during storage of sawdust from pine and spruce by using gas chromatography - Mass spectrometry (GC-MS) and VIS-NIR-spectroscopy

    Energy Technology Data Exchange (ETDEWEB)

    Arshadi, Mehrdad; Nilsson, David; Geladi, Paul (Unit of Biomass Technology and Chemistry, Swedish Univ. of Agricultural Sciences, SE-904 03 Umeaa (Sweden)). e-mail: mehrdad.arshadi@btk.slu.se

    2008-10-15

    Fuel pellets made of sawdust represent a renewable energy source for heat production. The raw material comes from sawmills and sawdust is used in the pellet mills and for reasons of logistics there is a need for storage of large quantities of the raw material. Long-term storage induces changes in the sawdust and therefore processing parameters for pellets production have to be adapted. This makes knowledge of storage time or maturity necessary. Two examples of experimental studies are presented: An industrial storage of pine and spruce sawdust was carried out over a period of 16 weeks in order to monitor the changes in the quality of sawdust during storage. Samples were taken out every week and all samples were analysed by VIS-NIR spectroscopy while some samples were analysed by GC-MS for their composition of fatty- and resin acids. The resulting data were subjected to multivariate data analysis. GC-MS data showed the difference between pine and spruce sawdust and the influence of maturity. This maturity effect could be associated with the decrease in fatty- and resin acids due to auto oxidative reactions. Multivariate analysis of the VIS-NIR data showed a major effect due to maturity associated with a colour change and also weaker effects of fatty- and resin acids differences. PLS regression was used to predict the storage time with RMSEP values between 10 and 15 days. However, since weather conditions, precipitation and seasonal variation have high influence on the speed of maturing of sawdust it will be necessary to continuously determine the degree of maturity. A second similar study is used as a complementary way of corroborating the results of the first one

  10. Method-MS. Final report

    International Nuclear Information System (INIS)

    Skipperud, L.; Popic, J.M.; Roos, P.; Salminen, S.; Nygren, U.; Sigmarsson, O.; Palsson, S.E.

    2011-05-01

    Radiometric determination methods, such as alpha spectrometry require long counting times when low activities are to be determined. Mass spectrometric techniques as Inductively Coupled Plasma Mass Spectrometry (ICP-MS), Thermal Ionisation Mass Spectrometry (TIMS) and Accelerator Mass Spectrometry (AMS) have shown several advantages compared to traditional methods when measuring long-lived radionuclides. Mass spectrometric methods for determination of very low concentrations of elemental isotopes, and thereby isotopic ratios, have been developed using a variety of ion sources. Although primarily applied to the determination of the lighter stable element isotopes and radioactive isotopes in geological studies, the techniques can equally well be applied to the measurement of activity concentrations of long-lived low-level radionuclides in various samples using 'isotope dilution' methods such as those applied in inductively coupled plasma mass spectrometry (ICP-MS). Due to the low specific activity of long-lived radionuclides, many of these are more conveniently detected using mass spectrometric techniques. Mass spectrometry also enables the individual determination of Pu-239 and Pu-240, which cannot be obtained by alpha spectrometry. Inductively Coupled Plasma Mass Spectrometry (ICP-MS) are rapidly growing techniques for the ultra-trace analytical determination of stable and long-lived isotopes and have a wide potential within environmental science, including ecosystem tracers and radio ecological studies. Such instrumentation, of course needs good radiochemical separation, to give best performance. The objectives of the project is to identify current needs and problems within low-level determination of long-lived radioisotopes by ICP-MS, to perform intercalibration and development and improvement of ICP-MS methods for the measurement of radionuclides and isotope ratios and to develop new methods based on modified separation chemistry applied to new auxiliary

  11. Method-MS. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Skipperud, L.; Popic, J.M. (Norwegian Univ. of Life Science (UMB), Isotope Lab. (Norway)); Roos, P. (Technical Univ. of Denmark, Risoe National Lab. for Sustainable Energy, Roskilde (Denmark)); Salminen, S. (Univ. of Helsinki (UH) (Finland)); Nygren, U. (Swedish Defence Research Agency (FOI) (Sweden)); Sigmarsson, O.; Palsson, S.E. (Univ. of Iceland/Icelandic Radiation Protection Institute (Iceland))

    2011-05-15

    Radiometric determination methods, such as alpha spectrometry require long counting times when low activities are to be determined. Mass spectrometric techniques as Inductively Coupled Plasma Mass Spectrometry (ICP-MS), Thermal Ionisation Mass Spectrometry (TIMS) and Accelerator Mass Spectrometry (AMS) have shown several advantages compared to traditional methods when measuring long-lived radionuclides. Mass spectrometric methods for determination of very low concentrations of elemental isotopes, and thereby isotopic ratios, have been developed using a variety of ion sources. Although primarily applied to the determination of the lighter stable element isotopes and radioactive isotopes in geological studies, the techniques can equally well be applied to the measurement of activity concentrations of long-lived low-level radionuclides in various samples using 'isotope dilution' methods such as those applied in inductively coupled plasma mass spectrometry (ICP-MS). Due to the low specific activity of long-lived radionuclides, many of these are more conveniently detected using mass spectrometric techniques. Mass spectrometry also enables the individual determination of Pu-239 and Pu-240, which cannot be obtained by alpha spectrometry. Inductively Coupled Plasma Mass Spectrometry (ICP-MS) are rapidly growing techniques for the ultra-trace analytical determination of stable and long-lived isotopes and have a wide potential within environmental science, including ecosystem tracers and radio ecological studies. Such instrumentation, of course needs good radiochemical separation, to give best performance. The objectives of the project is to identify current needs and problems within low-level determination of long-lived radioisotopes by ICP-MS, to perform intercalibration and development and improvement of ICP-MS methods for the measurement of radionuclides and isotope ratios and to develop new methods based on modified separation chemistry applied to new

  12. Quality evaluation of mycelial Antrodia camphorata using high-performance liquid chromatography (HPLC coupled with diode array detector and mass spectrometry (DAD-MS

    Directory of Open Access Journals (Sweden)

    Leung Kelvin

    2010-01-01

    Full Text Available Abstract Background Antrodia camphorata (AC is an important fungus native to Taiwanese forested regions. Scientific studies have demonstrated that extracts of AC possess a variety of pharmacological functions. This study aims to identify the full profile fingerprint of nucleosides and nucleobases in mycelial AC and to assess the quality of two commercial mycelial AC products. Methods High-performance liquid chromatography coupled with diode array detector and mass spectrometry was employed to identify the major components in mycelial AC. The chemical separation was carried out using a gradient program on a reverse phase Alltima C18 AQ analytical column (250 × 4.6 mm, 5 μm with the mobile phase consisting of deionized water and methanol. Results Ten nucleosides and nucleobases, two maleimide derivatives, and a sterol were identified as the major constituents in mycelial AC. These groups of chemical compounds constitute the first chromatographic fingerprint as an index for quality assessment of this medicinal fungus. Conclusions This study provides the first chromatographic fingerprint to assess the quality of mycelial AC.

  13. Polybrominated diphenyl ethers (PBDEs) contents in house and car dust of Portugal by pressurized liquid extraction (PLE) and gas chromatography-mass spectrometry (GC-MS).

    Science.gov (United States)

    Cunha, S C; Kalachova, K; Pulkrabova, J; Fernandes, J O; Oliveira, M B P P; Alves, A; Hajslova, J

    2010-03-01

    Dust is the repository of various compounds including flame retardants. In this study an analytical method based on PLE extraction and gas chromatography-mass spectrometry was selected for the analysis of 16 PBDEs congeners in house and car dust samples collected in Portugal. The analytical performance of the method was validated using standard reference material (SRM); values from 90% to 109% and from 2% to 11% were obtained for recovery and precision, respectively. The PBDE congeners distribution in whole and sieved fractions of the dust samples, as well as influence of the source on the levels of these contaminants, were obtained. The wide range of PBDEs contents found in the dust samples indicates heterogeneous levels of contamination in these matrices. The clearest feature of the results obtained was that Deca-BDE was the main PBDE in both house and car dust samples. The total PBDEs measured in house dust (ranging from 34 to 1928 ng g(-1)) was lower than those found in car dust (ranging from 193 to 22955 ng g(-1)). However, house dust provides a major contribution to human exposure due to the time spent there, much higher than in cars. Copyright (c) 2009 Elsevier Ltd. All rights reserved.

  14. Determination of Cd, Pb, Zn and Cu in Sediment Compartments by Sequential Extraction and Isotope Dilution Inductively Coupled Plasma Mass Spectrometry (ID-ICP-MS

    Directory of Open Access Journals (Sweden)

    Gardolinski Paulo C. F. C.

    2002-01-01

    Full Text Available Trace concentrations of Cd, Cu, Pb and Zn in four different sediment fractions extracted in sequence were determined by isotope dilution inductively coupled mass spectrometry (IDICPMS. The metals from each fraction were extracted following the sequential extraction procedure recommended by the Bureau Commun de Référence (BCR of the Commission of the European Communities. As an alternative to external calibration, the elements were quantified by spiking the extracted solutions with 112Cd, 63Cu, 208Pb and 66Zn and application of isotope dilution. The proposed approach was applied to a sample collected from a lake and two standard reference materials, NIST2704 river sediment from the National Institute of Standards & Technology and the BCR-277 estuarine sediment. Detection limits, for each extracted solution, varied from 0.31 to 0.53 mug L¹ for Cd, 0.92 to 2.9 mug L¹ for Cu, 0.22 to 1.1 mug L¹ for Pb and 1.3 to 7.6 mug L¹ for Zn. The sum of the metals concentration in the different fractions was compatible with 95% confidence level found amounts obtained with complete digestion of the samples and with the certified values of the standard reference materials.

  15. Standard practice for the determination of 237Np, 232Th, 235U and 238U in urine by inductively coupled plasma-Mass spectrometry (ICP-MS) and gamma ray spectrometry.

    CERN Document Server

    American Society for Testing and Materials. Philadelphia

    2005-01-01

    1.1 This practice covers the separation and preconcentration of neptunium-237 (237Np), thorium-232 (232Th), uranium-235 (235U) and uranium-238 (238U) from urine followed by quantitation using ICP-MS. 1.2 This practice can be used to support routine bioassay programs. The minimum detectable concentrations (MDC) for this method, taking the preconcentration factor into account, are approximately 1E-2Bq for 237Np (0.38ng), 2E-6Bq for 232Th (0.50ng), 4E-5Bq for 235U (0.50ng) and 6E-6Bq for 238U (0.48ng). 1.3 This standard does not purport to address all of the safety problems, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.

  16. Atmospheric pressure gas chromatography–time-of-flight-mass spectrometry (APGC–ToF-MS) for the determination of regulated and emerging contaminants in aqueous samples after stir bar sorptive extraction (SBSE)

    International Nuclear Information System (INIS)

    Pintado-Herrera, Marina G.; González-Mazo, Eduardo; Lara-Martín, Pablo A.

    2014-01-01

    Graphical abstract: Examples of identification of target (triclosan, TCS) and non-target (tributhyl phosphate, TBP) compounds in environmental water samples by APGC–ToF-MS. Some confirmation criteria are shown (i.e. mass spectra, isotopic distribution, and accurate mass). - Highlights: • 102 regulated and emerging contaminants are simultaneously extracted by SBSE. • APGC–ToF-MS is presented as an alternative to EI for the analysis of microcontaminants. • Identification of non-target compounds in environmental matrices is also explored. - Abstract: This work presents the development, optimization and validation of a multi-residue method for the simultaneous determination of 102 contaminants, including fragrances, UV filters, repellents, endocrine disruptors, biocides, polycyclic aromatic hydrocarbons (PAHs), polychlorinated biphenyls (PCBs), and several types of pesticides in aqueous matrices. Water samples were processed using stir bar sorptive extraction (SBSE) after the optimization of several parameters: agitation time, ionic strength, presence of organic modifiers, pH, and volume of the derivatizing agent. Target compounds were extracted from the bars by liquid desorption (LD). Separation, identification and quantification of analytes were carried out by gas chromatography (GC) coupled to time-of-flight (ToF-MS) mass spectrometry. A new ionization source, atmospheric pressure gas chromatography (APGC), was tested. The optimized protocol showed acceptable recovery percentages (50–100%) and limits of detection below 1 ng L −1 for most of the compounds. Occurrence of 21 out of 102 analytes was confirmed in several environmental aquatic matrices, including seawater, sewage effluent, river water and groundwater. Non-target compounds such as organophosphorus flame retardants were also identified in real samples by accurate mass measurement of their molecular ions using GC-APGC–ToF-MS. To the best of our knowledge, this is the first time that this

  17. Theory of the Protein Equilibrium Population Snapshot by H/D Exchange Electrospray Ionization Mass Spectrometry (PEPS-HDX-ESI-MS) Method used to obtain Protein Folding Energies/Rates and Selected Supporting Experimental Evidence.

    Science.gov (United States)

    Liyanage, Rohana; Devarapalli, Nagarjuna; Pyland, Derek B; Puckett, Latisha M; Phan, N H; Starch, Joel A; Okimoto, Mark R; Gidden, Jennifer; Stites, Wesley E; Lay, Jackson O

    2012-12-15

    Protein equilibrium snapshot by hydrogen/deuterium exchange electrospray ionization mass spectrometry (PEPS-HDX-ESI-MS or PEPS) is a method recently introduced for estimating protein folding energies and rates. Herein we describe the basis for this method using both theory and new experiments. Benchmark experiments were conducted using ubiquitin because of the availability of reference data for folding and unfolding rates from NMR studies. A second set of experiments was also conducted to illustrate the surprising resilience of the PEPS to changes in HDX time, using staphylococcal nuclease and time frames ranging from a few seconds to several minutes. Theory suggests that PEPS experiments should be conducted at relatively high denaturant concentrations, where the protein folding/unfolding rates are slow with respect to HDX and the life times of both the closed and open states are long enough to be sampled experimentally. Upon deliberate denaturation, changes in folding/unfolding are correlated with associated changes in the ESI-MS signal upon fast HDX. When experiments are done quickly, typically within a few seconds, ESI-MS signals, corresponding to the equilibrium population of the native (closed) and denatured (open) states can both be detected. The interior of folded proteins remains largely un-exchanged. Amongst MS methods, the simultaneous detection of both states in the spectrum is unique to PEPS and provides a "snapshot" of these populations. The associated ion intensities are used to estimate the protein folding equilibrium constant (or the free energy change, ΔG). Linear extrapolation method (LEM) plots of derived ΔG values for each denaturant concentration can then be used to calculate ΔG in the absence of denaturant, ΔG(H(2)O). In accordance with the requirement for detection of signals for both the folded and unfolded states, this theoretical framework predicts that PEPS experiments work best at the middle of the denaturation curve where natured

  18. Atmospheric pressure gas chromatography–time-of-flight-mass spectrometry (APGC–ToF-MS) for the determination of regulated and emerging contaminants in aqueous samples after stir bar sorptive extraction (SBSE)

    Energy Technology Data Exchange (ETDEWEB)

    Pintado-Herrera, Marina G.; González-Mazo, Eduardo; Lara-Martín, Pablo A., E-mail: pablo.lara@uca.es

    2014-12-03

    Graphical abstract: Examples of identification of target (triclosan, TCS) and non-target (tributhyl phosphate, TBP) compounds in environmental water samples by APGC–ToF-MS. Some confirmation criteria are shown (i.e. mass spectra, isotopic distribution, and accurate mass). - Highlights: • 102 regulated and emerging contaminants are simultaneously extracted by SBSE. • APGC–ToF-MS is presented as an alternative to EI for the analysis of microcontaminants. • Identification of non-target compounds in environmental matrices is also explored. - Abstract: This work presents the development, optimization and validation of a multi-residue method for the simultaneous determination of 102 contaminants, including fragrances, UV filters, repellents, endocrine disruptors, biocides, polycyclic aromatic hydrocarbons (PAHs), polychlorinated biphenyls (PCBs), and several types of pesticides in aqueous matrices. Water samples were processed using stir bar sorptive extraction (SBSE) after the optimization of several parameters: agitation time, ionic strength, presence of organic modifiers, pH, and volume of the derivatizing agent. Target compounds were extracted from the bars by liquid desorption (LD). Separation, identification and quantification of analytes were carried out by gas chromatography (GC) coupled to time-of-flight (ToF-MS) mass spectrometry. A new ionization source, atmospheric pressure gas chromatography (APGC), was tested. The optimized protocol showed acceptable recovery percentages (50–100%) and limits of detection below 1 ng L{sup −1} for most of the compounds. Occurrence of 21 out of 102 analytes was confirmed in several environmental aquatic matrices, including seawater, sewage effluent, river water and groundwater. Non-target compounds such as organophosphorus flame retardants were also identified in real samples by accurate mass measurement of their molecular ions using GC-APGC–ToF-MS. To the best of our knowledge, this is the first time that this

  19. Gas-Chromatography Mass-Spectrometry (GC-MS Based Metabolite Profiling Reveals Mannitol as a Major Storage Carbohydrate in the Coccolithophorid Alga Emiliania huxleyi

    Directory of Open Access Journals (Sweden)

    Alisdair R. Fernie

    2013-03-01

    Full Text Available Algae are divergent organisms having a wide variety of evolutional histories. Although most of them share photosynthetic activity, their pathways of primary carbon metabolism are rather diverse among species. Here we developed a method for gas chromatography-mass spectroscopy (GC-MS based metabolite profiling for the coccolithophorid alga Emiliania huxleyi, which is one of the most abundant microalgae in the ocean, in order to gain an overview of the pathway of primary metabolism within this alga. Following method optimization, twenty-six metabolites could be detected by this method. Whilst most proteogenic amino acids were detected, no peaks corresponding to malate and fumarate were found. The metabolite profile of E. huxleyi was, however, characterized by a prominent accumulation of mannitol reaching in excess of 14 nmol 106 cells−1. Similarly, the accumulation of the 13C label during short term H13CO3− feeding revealed a massive redistribution of label into mannitol as well as rapid but saturating label accumulation into glucose and several amino acids including aspartate, glycine and serine. These results provide support to previous work suggesting that this species adopts C3 photosynthesis and that mannitol functions as a carbon store in E. huxleyi.

  20. Determination of low levels of perchlorate in lettuce and spinach using ion chromatography-electrospray ionization mass spectrometry (IC-ESI-MS).

    Science.gov (United States)

    Seyfferth, Angelia L; Parker, David R

    2006-03-22

    A sample preparation method was developed to quantify environmentally relevant (low micrograms per liter) concentrations of perchlorate (ClO4(-)) in leafy vegetables using IC-ESI-MS. Lettuce and spinach were macerated, centrifuged, and filtered, and the aqueous extracts were rendered water-clear using a one-step solid-phase extraction method. Total time for extraction and sample preparation was 6 h. Ion suppression was demonstrated and was likely due to unknown organics still present in the extract solution after cleanup. However, this interference was readily eliminated using a Cl(18)O4(-) internal standard at 1 microg/L in all standards and samples. Hydroponically grown perchlorate-free butterhead lettuce was spiked to either 10.3 or 37.7 microg/kg of fresh weight (FW), and recoveries were between 91 and 98% and between 93 and 101%, respectively. Five types of lettuce and spinach from a local grocery store were then analyzed; they contained from 0.6 to 6.4 microg/kg of FW. Spike recoveries using the store-bought samples ranged from 89 to 100%. The method detection limit for perchlorate in plant extracts is 40 ng/L, and the corresponding minimum reporting limit is 200 ng/L or 0.8 microg/kg of FW.