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Sample records for gas chromatography ion-trap

  1. Determination of anabolic steroids with gas chromatography-ion trap mass spectrometry using hydrogen as carrier gas.

    Science.gov (United States)

    Impens, S; De Wasch, K; De Brabander, H

    2001-01-01

    Helium is considered to be the ideal carrier gas for gas chromatography/mass spectrometry (GC/MS) in general, and for use with an ion trap in particular. Helium is an inert gas, can be used without special precautions for security and, moreover, it is needed as a damping gas in the trap. A disadvantage of helium is the high viscosity resulting in long GC run times. In this work hydrogen was tested as an alternative carrier gas for GC in performing GC/MS analyses. A hydrogen generator was used as a safe source of hydrogen gas. It is demonstrated that hydrogen can be used as a carrier gas for the gas chromatograph in combination with helium as make-up gas for the trap. The analysis time was thus shortened and the chromatographic performance was optimized. Although hydrogen has proven useful as a carrier gas in gas chromatography coupled to standard detectors such as ECD or FID, its use is not mentioned extensively in the literature concerning gas chromatography-ion trap mass spectrometry. However, it is worth considering as a possibility because of its chromatographic advantages and its advantageous price when using a hydrogen generator. Copyright 2001 John Wiley & Sons, Ltd.

  2. Determination of interfering triazine degradation products by gas chromatography-ion trap mass spectrometry.

    Science.gov (United States)

    Magnuson, M L; Speth, T F; Kelty, C A

    2000-01-28

    Deethylatrazine (DEA), an atrazine degradation product, has been added to the US Environmental Protection Agency's Drinking Water Contaminant Candidate List (CCL). In its gas chromatographic analysis, DEA can coelute with deisopropylatrazine (DIA), another degradation product. The present work demonstrates that the coelution of DEA and DIA can induce a significant (up to approximately 50%) positive bias in the DEA determination, when using an ion-trap mass spectrometer as the detector. The DIA determination is unaffected by the coelution within experimental error. This may be explained in terms of gas-phase ion fragment populations. A correction factor to the observed DEA concentration may be developed based on the measured DIA concentration.

  3. Detection of lysergic acid diethylamide (LSD) in urine by gas chromatography-ion trap tandem mass spectrometry.

    Science.gov (United States)

    Sklerov, J H; Kalasinsky, K S; Ehorn, C A

    1999-10-01

    A confirmatory method for the detection and quantitation of lysergic acid diethylamide (LSD) is presented. The method employs gas chromatography-tandem mass spectrometry (GC-MS-MS) using an internal ionization ion trap detector for sensitive MS-MS-in-time measurements of LSD extracted from urine. Following a single-step solid-phase extraction of 5 mL of urine, underivatized LSD can be measured with limits of quantitation and detection of 80 and 20 pg/mL, respectively. Temperature-programmed on-column injections of urine extracts were linear over the concentration range 20-2000 pg/mL (r2 = 0.999). Intraday and interday coefficients of variation were LSD-positive samples in this laboratory. Comparisons with alternate GC-MS methods and extraction procedures are discussed.

  4. Characterization of the synthesis of N,N-dimethyltryptamine by reductive amination using gas chromatography ion trap mass spectrometry.

    Science.gov (United States)

    Brandt, Simon D; Moore, Sharon A; Freeman, Sally; Kanu, Abu B

    2010-07-01

    The present study established an impurity profile of a synthetic route to the hallucinogenic N,N-dimethyltryptamine (DMT). The synthesis was carried out under reductive amination conditions between tryptamine and aqueous formaldehyde in the presence of acetic acid followed by reduction with sodium cyanoborohydride. Analytical characterization of this synthetic route was carried out by gas chromatography ion trap mass spectrometry using electron- and chemical-ionization modes. Methanol was employed as a liquid CI reagent and the impact of stoichiometric modifications on side-products formation was also investigated. Tryptamine 1, DMT 2, 2-methyltetrahydro-β-carboline (2-Me-THBC, 3), N-methyl-N-cyanomethyltryptamine (MCMT, 4), N-methyltryptamine (NMT, 5), 2-cyanomethyl-tetrahydro-β-carboline (2-CM-THBC, 6) and tetrahydro-β-carboline (THBC, 7) have been detected under a variety of conditions. Replacement of formaldehyde solution with paraformaldehyde resulted in incomplete conversion of the starting material whereas a similar replacement of sodium cyanoborohydride with sodium borohydride almost exclusively produced THBC instead of the expected DMT. Compounds 1 to 7 were quantified and the limits of detection were 28.4, 87.7, 21.5, 23.4, 41.1, 36.6, and 34.9 ng mL(-1), respectively. The limits of quantification for compounds 1 to 7 were 32.4, 88.3, 25.4, 24.6, 41.4, 39.9, and 37.0 µg mL(-1), respectively. Linearity was observed in the range of 20.8-980 µg mL(-1) with correlation coefficients > 0.99. The application holds great promise in the area of forensic chemistry where development of reliable analytical methods for the detection, identification, and quantification of DMT are crucial and also in pharmaceutical analysis where DMT might be prepared for use in human clinical studies. Copyright 2010 John Wiley & Sons, Ltd.

  5. Miniaturized GC/MS instrumentation for in situ measurements: micro gas chromatography coupled with miniature quadrupole array and paul ion trap mass spectrometers

    Science.gov (United States)

    Holland, P.; Chutjian, A.; Darrach, M.; Orient, O.

    2002-01-01

    Miniaturized chemical instrumentation is needed for in situ measurements in planetary exploration and other spaceflight applications where factors such as reduction in payload requirements and enhanced robustness are important. In response to this need, we are 'continuing to develop miniaturized GC/MS instrumentation which combines chemical separations by gas chromatography (GC) with mass spectrometry (MS) to provide positive identification of chemical compounds in complex mixtures of gases, such as those found in the International Space Station's cabin atmosphere. Our design approach utilizes micro gas chromatography components coupled with either a miniature quadrupole mass spectrometer array (QMSA) or compact, high-resolution Paul ion trap.

  6. Use of solid-phase microextraction for the detection of acetic acid by ion-trap gas chromatography-mass spectrometry and application to indoor levels in museums.

    Science.gov (United States)

    Godoi, Ana F L; Van Vaeck, Luc; Van Grieken, René

    2005-03-04

    A simple and efficient method using solid-phase microextraction (SPME) and gas chromatography-ion trap mass spectrometry (GC-ITMS) was developed for the analysis of acetic acid in air. The choice of the SPME fibre revealed to be critical as well as the sampling and desorption time. A dilution vessel was used for calibration. The precision of the method was found to be 4.7% relative standard deviation (RSD) and the detection limit 5.7 microg m(-3). The SPME-GC-MS technique was applied to the analysis of acetic acid in museum atmospheres.

  7. Method for detection of trace metal and metalloid contaminants in coal-generated fuel gas using gas chromatography/ion trap mass spectrometry.

    Science.gov (United States)

    Rupp, Erik C; Granite, Evan J; Stanko, Dennis C

    2010-07-15

    There exists an increasing need to develop a reliable method to detect trace contaminants in fuel gas derived from coal gasification. While Hg is subject to current and future regulations, As, Se, and P emissions may eventually be regulated. Sorbents are the most promising technology for the removal of contaminants from coal-derived fuel gas, and it will be important to develop a rapid analytical detection method to ensure complete removal and determine the ideal time for sorbent replacement/regeneration in order to reduce costs. This technical note explores the use of a commercial gas chromatography/ion trap mass spectrometry system for the detection of four gaseous trace contaminants in a simulated fuel gas. Quantitative, repeatable detection with limits at ppbv to ppmv levels were obtained for arsine (AsH(3)), phosphine (PH(3)), and hydrogen selenide (H(2)Se), while qualitative detection was observed for mercury. Decreased accuracy and response caused by the primary components of fuel gas were observed.

  8. A selective and sensitive method for quantitation of lysergic acid diethylamide (LSD) in whole blood by gas chromatography-ion trap tandem mass spectrometry.

    Science.gov (United States)

    Libong, Danielle; Bouchonnet, Stéphane; Ricordel, Ivan

    2003-01-01

    A gas chromatography-ion trap tandem mass spectrometry (GC-ion trap MS-MS) method for detection and quantitation of LSD in whole blood is presented. The sample preparation process, including a solid-phase extraction step with Bond Elut cartridges, was performed with 2 mL of whole blood. Eight microliters of the purified extract was injected with a cold on-column injection method. Positive chemical ionization was performed using acetonitrile as reagent gas; LSD was detected in the MS-MS mode. The chromatograms obtained from blood extracts showed the great selectivity of the method. GC-MS quantitation was performed using lysergic acid methylpropylamide as the internal standard. The response of the MS was linear for concentrations ranging from 0.02 ng/mL (detection threshold) to 10.0 ng/mL. Several parameters such as the choice of the capillary column, the choice of the internal standard and that of the ionization mode (positive CI vs. EI) were rationalized. Decomposition pathways under both ionization modes were studied. Within-day and between-day stability were evaluated.

  9. Development and validation of automatic HS-SPME with a gas chromatography-ion trap/mass spectrometry method for analysis of volatiles in wines.

    Science.gov (United States)

    Paula Barros, Elisabete; Moreira, Nathalie; Elias Pereira, Giuliano; Leite, Selma Gomes Ferreira; Moraes Rezende, Claudia; Guedes de Pinho, Paula

    2012-11-15

    An automated headspace solid-phase microextraction (HS-SPME) combined with gas chromatography-ion trap/mass spectrometry (GC-IT/MS) was developed in order to quantify a large number of volatile compounds in wines such as alcohols, ester, norisoprenoids and terpenes. The procedures were optimized for SPME fiber selection, pre-incubation temperature and time, extraction temperature and time, and salt addition. A central composite experimental design was used in the optimization of the extraction conditions. The volatile compounds showed optimal extraction using a DVB/CAR/PDMS fiber, incubation of 5 ml of wine with 2g NaCl at 45 °C during 5 min, and subsequent extraction of 30 min at the same temperature. The method allowed the identification of 64 volatile compounds. Afterwards, the method was validated successfully for the most significant compounds and was applied to study the volatile composition of different white wines. Copyright © 2012 Elsevier B.V. All rights reserved.

  10. Rapid and sensitive gas chromatography ion-trap mass spectrometry method for the determination of tobacco specific N-nitrosamines in secondhand smoke

    Energy Technology Data Exchange (ETDEWEB)

    SLEIMAN, Mohamad; MADDALENA, Randy L.; GUNDEL, Lara A.; DESTAILLATS, Hugo

    2009-07-01

    Tobacco-specific nitrosamines (TSNAs) are some of the most potent carcinogens in tobacco and cigarette smoke. Accurate quantification of these chemicals is needed to help assess public health risks. We developed and validated a specific and sensitive method to measure four TSNAs in both the gas- and particle-phase of secondhand smoke (SHS) using gas chromatography and ion-trap tandem mass spectrometry,. A smoking machine in an 18-m3 room-sized chamber generated relevant concentrations of SHS that were actively sampled on Teflon coated fiber glass (TCFG) filters, and passively sampled on cellulose substrates. A simple solid-liquid extraction protocol using methanol as solvent was successfully applied to both filters with high recoveries ranging from 85 to 115percent. Tandem MS parameters were optimized to obtain the best sensitivity in terms of signal to-noise ratio (S/N) for the target compounds. For each TSNA, the major fragmentation pathways as well as ion structures were elucidated and compared with previously published data. The method showed excellent performances with a linear dynamic range between 2 and 1000 ng mL-1, low detection limits (S/N> 3) of 30-300 pg.ml-1 and precision with experimental errors below 10percent for all compounds. Moreover, no interfering peaks were observed indicating a high selectivity of MS/MS without the need for a sample clean up step. The sampling and analysis method provides a sensitive and accurate tool to detect and quantify traces of TSNA in SHS polluted indoor environments.

  11. Determination of N,N-dimethyltryptamine in beverages consumed in religious practices by headspace solid-phase microextraction followed by gas chromatography ion trap mass spectrometry.

    Science.gov (United States)

    Gaujac, Alain; Dempster, Nicola; Navickiene, Sandro; Brandt, Simon D; de Andrade, Jailson Bittencourt

    2013-03-15

    A novel analytical approach combining solid-phase microextraction (SPME)/gas chromatography ion trap mass spectrometry (GC-IT-MS) was developed for the detection and quantification N,N-dimethyltryptamine (DMT), a powerful psychoactive indole alkaloid present in a variety of South American indigenous beverages, such as ayahuasca and vinho da jurema. These particular plant products, often used within a religious context, are increasingly consumed throughout the world following an expansion of religious groups and the availability of plant material over the Internet and high street shops. The method described in the present study included the use of SPME in headspace mode combined GC-IT-MS and included the optimization of the SPME procedure using multivariate techniques. The method was performed with a polydimethylsiloxane/divinylbenzene (PDMS/DVB) fiber in headspace mode (70 min at 60 °C) which resulted in good precision (RSD<8.6%) and accuracy values (71-109%). Detection and quantification limits obtained for DMT were 0.78 and 9.5 mg L(-1), respectively and good linearity (1.56-300 mg L(-1), r(2)=0.9975) was also observed. In addition, the proposed method showed good robustness and allowed for the minimization of sample manipulation. Five jurema beverage samples were prepared in the laboratory in order to study the impact of temperature, pH and ethanol on the ability to extract DMT into solution. The developed method was then applied to the analysis of twelve real ayahuasca and vinho da jurema samples, obtained from Brazilian religious groups, which revealed DMT concentration levels between 0.10 and 1.81 g L(-1). Copyright © 2013 Elsevier B.V. All rights reserved.

  12. Determination of cis-permethrin, trans-permethrin and associated metabolites in rat blood and organs by gas chromatography-ion trap mass spectrometry.

    Science.gov (United States)

    Lestremau, F; Willemin, M-E; Chatellier, C; Desmots, S; Brochot, C

    2014-05-01

    An analytical method was developed to measure cis-permethrin and trans-permethrin in different biological rat matrices and fluids (whole blood, red blood cells, plasma, brain, liver, muscle, testes, kidneys, fat and faeces). The method was also suitable for the simultaneous quantification of their associated metabolites [cis-3-(2,2-dichlorovinyl)-2,2-dimethyl-(1-cyclopropane) carboxylic acid (cis-DCCA), trans-3-(2,2-dichlorovinyl)-2,2-dimethyl-(1-cyclopropane) carboxylic acid (trans-DCCA) and 3-phenoxybenzoic acid (3-PBA)] in blood (whole blood, red blood cells, plasma) and liver. The target analytes were derivatised in samples using a methanolic/hydrochloric acid solution and then extracted with toluene. The analysis was performed by gas chromatography, and detection using ion trap tandem mass spectrometry. The selectivity obtained for complex matrices such as rat organs allowed the use of a purification step to be avoided for most of the matrices investigated. In the case of fat, where permethrin is suspected to accumulate, a dedicated purification step was developed. In fluids, the limits of quantification were at the 50 ng/mL level for the parent compounds and 3-PBA and at 25 ng/mL for cis-DCCA and trans-DCCA. For solid matrices excluding fat, the limits of quantification ranged from 50 ng/g for muscle to 100 ng/g for brain and testes for both cis-permethrin and trans-permethrin. The extraction recoveries ranged primarily between 80 and 120% for the matrix tested. The stability of blood samples was tested through the addition of 1% v/v formic acid. The methods developed were applied in a toxicokinetic study in adult rats. cis-Permethrin and the metabolites were detected in all corresponding matrices, whereas trans-permethrin was detected only in blood, plasma and faeces.

  13. Comparative study of comprehensive gas chromatography-nitrogen chemiluminescence detection and gas chromatography-ion trap-tandem mass spectrometry for determining nicotine and carcinogen organic nitrogen compounds in thirdhand tobacco smoke.

    Science.gov (United States)

    Ramírez, Noelia; Vallecillos, Laura; Lewis, Alastair C; Borrull, Francesc; Marcé, Rosa M; Hamilton, Jacqueline F

    2015-12-24

    Thirdhand tobacco smoke (THS) constitutes a poorly understood pathway of exposure of non-smokers, especially toddlers, to tobacco-related carcinogens. However, to date most of the carcinogens present in tobacco smoke have not been detected in THS and, therefore, the significance of THS health risk is still unknown. In this study, we have compared the performance of two analytical methods - one based on gas chromatography coupled to ion trap mass spectrometry detection (GC-IT-MS) and the other on comprehensive two-dimensional gas chromatography coupled to a nitrogen chemiluminescence detector (GC×GC-NCD) - for simultaneously determining, in settled house dust, the presence of 16 organic nitrogen carcinogens already detected in tobacco smoke. The target compounds included four aromatic amines, two nitrocompounds, eight N-nitrosamines and two tobacco-specific nitrosamines, as well as nicotine as a tobacco marker. Dust samples were extracted using in-cell clean up pressurized liquid extraction with silica as clean up sorbent and ethyl acetate as the organic solvent, with average recovery of 89%. Although GC-IT-MS, using chemical ionization with methanol and tandem MS, performed well, the optimized GC×GC-NCD gave lower limits of detection (from 4 to 22ngg(-1)) and better repeatability and reproducibility a low concentration levels (%RSD<8%) and, therefore, was applicable for determining these different groups of carcinogens without the need for derivatization prior to the GC analysis. The performance of the optimized PLE/GC×GC-NCD method was tested by quantifying the target compounds in house dust samples from smokers' and non-smokers' homes. The median carcinogen compounds detected was 3.8μgg(-1) and 1.1μgg(-1) in smokers' and non-smokers' house dust, respectively. In this study, we have detected highly carcinogenic aromatic amines and nitro compounds for the first time in settled house dust complementing the state of knowledge of THS composition and providing

  14. Screening of drugs and toxic compounds with liquid chromatography-linear ion trap tandem mass spectrometry.

    Science.gov (United States)

    Sauvage, François-Ludovic; Saint-Marcoux, Franck; Duretz, Bénédicte; Deporte, Didier; Lachatre, Gérard; Marquet, Pierre

    2006-09-01

    In clinical and forensic toxicology, general unknown screening is used to detect and identify exogenous compounds. In this study, we aimed to develop a comprehensive general unknown screening method based on liquid chromatography coupled with a hybrid triple-quadrupole linear ion trap mass spectrometer. After solid-phase extraction, separation was performed using gradient reversed-phase chromatography. The mass spectrometer was operated in the information-dependent acquisition mode, switching between a survey scan acquired in the Enhanced Mass Spectrometry mode with dynamic subtraction of background noise and a dependent scan obtained in the enhanced product ion scan mode. The complete cycle time was 1.36 s. A library of 1000 enhanced product ion-tandem mass spectrometry spectra in positive mode and 250 in negative mode, generated using 3 alternated collision tensions during each scan, was created by injecting pure solutions of drugs and toxic compounds. Comparison with HPLC-diode array detection and gas chromatography-mass spectrometry for the analysis of 36 clinical samples showed that linear ion trap tandem mass spectrometry could identify most of the compounds (94% of the total). Some compounds were detected only by 1 of the other 2 techniques. Specific clinical cases highlighted the advantages and limitations of the method. A unique combination of new operating modes provided by hybrid triple-quadrupole linear ion trap mass spectrometers and new software features allowed development of a comprehensive and efficient method for the general unknown screening of drugs and toxic compounds in blood or urine.

  15. A liquid-phase microextraction method, combining a dual gauge microsyringe with a hollow fiber membrane, for the determination of organochlorine pesticides in aqueous solution by gas chromatography/ion trap mass spectrometry.

    Science.gov (United States)

    Yan, Chih-Hao; Wu, Hui-Fen

    2004-01-01

    A liquid-phase microextraction (LPME) method has been demonstrated for the extraction and determination of organochlorine pesticides (OCPs) in aqueous solution. The method combines a dual gauge microsyringe with a hollow fiber membrane (LPME/DGM-HF) followed by detection by gas chromatography/ion trap mass spectrometry (GC/ITMS). The advantages include speed, low solvent and sample consumption, simplicity and ease of use. The extraction time, solvent selection, salt concentration and sample stirring rate have been investigated in order to optimize extraction efficiency. The viability is evaluated by measuring the linearity and detection limit of the five OCPs in aqueous solution. Detection linearity for the OCPs has been achieved over a range of concentrations between 1 and 500 microg/L (r2 > 0.930), with a detection limit of 0.1 microg/L for each OCP. Copyright 2004 John Wiley & Sons, Ltd.

  16. Extraction and purification procedures for simultaneous quantification of phenolic xenoestrogens and steroid estrogens in river sediment by gas chromatography/ion trap mass spectrometry.

    Science.gov (United States)

    Kinani, Said; Bouchonnet, Stéphane; Bourcier, Sophie; Creusot, Nicolas; Porcher, Jean-Marc; Aït-Aïssa, Sélim

    2008-11-01

    A sensitive and simple method based on ultrasonication extraction with a hexane/acetone (2:1, v/v) mixture, followed by clean up of the extract by solid-phase extraction (SPE) and gas chromatography/mass spectrometry (GC/MS) detection, has been developed and validated for the analysis of 20 estrogenic endocrine-disrupting chemicals (EEDCs) including phenolic xenoestrogens, synthetic and natural estrogens in river sediment. After extraction and purification, analytes are derivatised with a BSTFA/TMCS/pyridine (49:1:50, v/v/v) mixture and quantified by GC/MS. The GC/MS method involves switching between electron ionisation (EI) and chemical ionisation (CI); it also switches between selected ion storage and tandem mass spectrometry detection. The applicability of the method has been demonstrated by analysing extracts of French river sediments for which bioanalytical tests (in vitro) had already shown that they were impacted by estrogenic endocrine disrupters. The biological contribution of all the products detected in each sediment extract was compared to the estrogenic activity measured by bioassays.

  17. Validation of an analytical method for analysis of cannabinoids in hair by headspace solid-phase microextraction and gas chromatography-ion trap tandem mass spectrometry.

    Science.gov (United States)

    Emídio, Elissandro Soares; Prata, Vanessa de Menezes; Dórea, Haroldo Silveira

    2010-06-18

    The development of an analytical method for the determination of Delta(9)-tetrahydrocannabinol (THC), cannabidiol (CBD) and cannabinol (CBN) in samples of human hair is described. Samples were subjected to a procedure based on the combination of headspace solid-phase microextraction (HS-SPME) with gas chromatography linked with mass spectrometry operating in tandem mode (GC-MS/MS). A 10 mg aliquot of sample was firstly decontaminated using petroleum ether, deionized water and dichloromethane (2 mL of each solvent), for 10 min under sonication, and then digested in alkaline solution (1 mol L(-1) NaOH). The method variables evaluated were pH, mass of hair, fiber type, extraction temperature, desorption time, ionic strength, pre-equilibrium time and extraction time. Parameters concerning operation of the tandem mode MS/MS were also assessed and optimized. Validation of the method demonstrated excellent linearity in the range 0.1-8.0 ng mg(-1), with regression coefficients better than 0.994. Precision was determined using two different concentrations (upper and lower limits of the linear range), and RSD values were between 6.6 and 16.4%. Absolute recoveries (measured in triplicate) were in the range 1.1-8.7%, and limits of detection and quantification were 0.007-0.031 ng mg(-1) and 0.012-0.062 ng mg(-1), respectively. The LOQ for THC (0.062 ng mg(-1)) was below the cut-off value (LOQ Toxicologie Analytique (SFTA). The optimized SPME method was applied in analysis of hair samples from Cannabis drug users, showing that CBN and CBD were present in all samples analyzed. 2010 Elsevier B.V. All rights reserved.

  18. Quantitative determination of sotolon, maltol and free furaneol in wine by solid-phase extraction and gas chromatography-ion-trap mass spectrometry.

    Science.gov (United States)

    Ferreira, Vicente; Jarauta, Idoia; López, Ricardo; Cacho, Juan

    2003-08-22

    A method for the analytical determination of sotolon [4,5-dimethyl-3-hydroxy-2(5H)-furanone], maltol [3-hydroxy-2-methyl-4H-pyran-4-one] and free furaneol [2,5-dimethyl-4-hydroxy-3(2H)-furanone] in wine has been developed. The analytes are extracted from 50 ml of wine in a solid-phase extraction cartridge filled with 800 mg of LiChrolut EN resins. Interferences are removed with 15 ml of a pentane-dichloromethane (20:1) solution, and analytes are recovered with 6 ml of dichloromethane. The extract is concentrated up to 0.1 ml and analyzed by GC-ion trap MS. Maltol and sotolon were determined by selected ion storage of ions in the m/z ranges 120-153 and 79-95, using the ions m/z 126 and 83 for quantitation, respectively. Furaneol was determined by non-resonant fragmentation of the m/z 128 mother ion and subsequent analysis of the m/z 81 ion. The detection limits of the method are in all cases between 0.5 and 1 microg l(-1), well below the olfactory thresholds of the compounds. The precision of the method is in the 4-5% range for levels in wine around 20 microg l(-1). Linearity holds at least up to 400 microg l(-1), and is satisfactory in all cases. The recoveries of maltol and sotolon are constant (70 and 64%, respectively) and do not depend on the type of wine. On the contrary, in the case of furaneol, red wines show constant and high recoveries (97%), while the recoveries on white wines range between 30 and 80%. Different experiments showed that this behavior is probably due to the existence of complexes formed between furaneol and sulphur dioxide or catechols. Sensory experiments confirmed that the complexed forms found in white wines are not perceived by orthonasal olfaction, and that the furaneol determined by the method can be considered as the free and odor-active fraction.

  19. Optimization of a microwave-assisted extraction large-volume injection and gas chromatography-ion trap mass spectrometry procedure for the determination of polybrominated diphenyl ethers, polybrominated biphenyls and polychlorinated naphthalenes in sediments

    Energy Technology Data Exchange (ETDEWEB)

    Yusa, V. [Analytical Chemistry Department, University of Valencia, Edifici Jeroni Munoz, 50th Dr. Moliner, 46100 Burjassot, Valencia (Spain); Pardo, O. [Analytical Chemistry Department, University of Valencia, Edifici Jeroni Munoz, 50th Dr. Moliner, 46100 Burjassot, Valencia (Spain); Pastor, A. [Analytical Chemistry Department, University of Valencia, Edifici Jeroni Munoz, 50th Dr. Moliner, 46100 Burjassot, Valencia (Spain)]. E-mail: Agustin.Pastor@uv.es; Guardia, M. de la [Analytical Chemistry Department, University of Valencia, Edifici Jeroni Munoz, 50th Dr. Moliner, 46100 Burjassot, Valencia (Spain)

    2006-01-31

    A sensitive and rapid method for the determination of polybrominated diphenyl ethers (PBDEs), polybrominated biphenyls (PBBs) and polychlorinated naphthalenes (PCNs) in sediment samples is proposed. The method involving microwave-assisted extraction (MAE) and large-volume injection (LVI) gas chromatography (GC)-ion trap mass spectrometry (ITMS), and the experimental conditions were optimized using the statistical design of experiments (DOE). A Plackett-Burman (P-B) design was chosen to estimate the influence of five factors, such as resonance excitation voltage (EV), isolation time (IT), excitation time (ET), ion source temperature (IST) and electron energy (EE) on the analytical response in the ITMS determination. In order to increase the analytical response, 70 {mu}L of the final extract were injected into the GC-tandem mass spectrometry (MS-MS) using a programmable temperature vaporizer (PTV). The factor settings involving injection temperature, vaporization temperature, vaporization time and flow during the evaporation step were previously optimized using a central composite design (CCD). The MAE was carried out using the hexane-acetone (1:1, v/v) mixture and the extraction conditions were optimized with a CCD. The highest response was obtained with a volume of 48 mL, a temperature of 152 deg. C and an extraction time of 24 min. The optimized method gives recoveries between 75 and 95% with relative standard deviations (R.S.D.) that ranged from 4 to 13%. The limit of detection (LOD) ranged between 4 and 20 pg g{sup -1} dry weight (dw) when 5 g of sediment were analyzed. The MAE method was applied to the analyses of polyhalogenated compounds in sediments collected in the harbour of Valencia (Spain). The proposed method may serve as an alternative for GC-negative chemical ionization (NCI)-MS and can be used in government testing programmes.

  20. Characterization of impurities in tylosin using dual liquid chromatography combined with ion trap mass spectrometry.

    Science.gov (United States)

    Chopra, Shruti; Van Schepdael, Ann; Hoogmartens, Jos; Adams, Erwin

    2013-03-15

    Investigation of unknown impurities in a tylosin sample was performed using liquid chromatography coupled to mass spectrometry (LC/MS). Separation was performed according to the recently described LC-UV method of Ashenafi et al. (2011) [14]. This method was reported to have a good selectivity as it was able to separate the four main components of tylosin from the already known and 23 unknown impurities. However, as this method uses a mobile phase with non-volatile constituents, direct characterization of these impurities using LC/MS was not possible. The impurity fractions were therefore first collected and then desalted before sending them to the MS. Identification of the impurities in the tylosin sample was performed with a quadruple ion trap (IT) MS, with an electrospray ionization (ESI) source in the positive ion mode. The structure of the impurities was deduced by comparing their fragmentation pattern with those of the main components of tylosin. As several peaks in the LC-UV method contained multiple compounds, using this method in total 41 new impurities were (partly) characterized. Copyright © 2012 Elsevier B.V. All rights reserved.

  1. Determination of vanillin, ethyl vanillin, and coumarin in infant formula by liquid chromatography-quadrupole linear ion trap mass spectrometry.

    Science.gov (United States)

    Shen, Yan; Han, Chao; Liu, Bin; Lin, Zhengfeng; Zhou, Xiujin; Wang, Chengjun; Zhu, Zhenou

    2014-02-01

    A simple, precise, accurate, and validated liquid chromatography-quadrupole linear ion trap mass spectrometry method was developed for the determination of vanillin, ethyl vanillin, and coumarin in infant formula samples. Following ultrasonic extraction with methanol/water (1:1, vol/vol), and clean-up on an HLB solid-phase extraction cartridge (Waters Corp., Milford, MA), samples were separated on a Waters XSelect HSS T3 column (150 × 2.1-mm i.d., 5-μm film thickness; Waters Corp.), with 0.1% formic acid solution-acetonitrile as mobile phase at a flow rate of 0.25 mL/min. Quantification of the target was performed by the internal standard approach, using isotopically labeled compounds for each chemical group, to correct matrix effects. Data acquisition was carried out in multiple reaction monitoring transitions mode, monitoring 2 multiple reaction monitoring transitions to ensure an accurate identification of target compounds in the samples. Additional identification and confirmation of target compounds were performed using the enhanced product ion modus of the linear ion trap. The novel liquid chromatography-quadrupole linear ion trap mass spectrometry platform offers the best sensitivity and specificity for characterization and quantitative determination of vanillin, ethyl vanillin, and coumarin in infant formula and fulfills the quality criteria for routine laboratory application. Copyright © 2014 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

  2. Profiling of lipid species by normal-phase liquid chromatography, nanoelectrospray ionization, and ion trap-orbitrap mass spectrometry

    DEFF Research Database (Denmark)

    Sokol, Elena; Almeida, Reinaldo; Hannibal-Bach, Hans Kristian

    2013-01-01

    chromatography-Fourier transform mass spectrometry (LC-FTMS) and LC-ITMS(2) (ion trap tandem mass spectrometry) for profiling and structural analysis of lipid species. The workflow uses a normal-phase LC system for efficient separation of apolar and polar lipid species combined with sensitive and specific...... analysis powered by a chip-based nanoelectrospray ion source and a hybrid ion trap-orbitrap mass spectrometer. The workflow was executed using a primary LC-FTMS survey routine for identification and profiling of lipid species based on high-mass accuracy and retention time followed by a targeted LC-ITMS(2...... of low-abundant triacylglycerol and ceramide species in mouse brain cerebellum and 3T3-L1 adipocytes, respectively. The workflow described here is generic and can be extended for detailed lipid analysis of sample matrices having a wide range of lipid compositions....

  3. Classification of jet fuels by fuzzy rule-building expert systems applied to three-way data by fast gas chromatography--fast scanning quadrupole ion trap mass spectrometry.

    Science.gov (United States)

    Sun, Xiaobo; Zimmermann, Carolyn M; Jackson, Glen P; Bunker, Christopher E; Harrington, Peter B

    2011-01-30

    A fast method that can be used to classify unknown jet fuel types or detect possible property changes in jet fuel physical properties is of paramount interest to national defense and the airline industries. While fast gas chromatography (GC) has been used with conventional mass spectrometry (MS) to study jet fuels, fast GC was combined with fast scanning MS and used to classify jet fuels into lot numbers or origin for the first time by using fuzzy rule-building expert system (FuRES) classifiers. In the process of building classifiers, the data were pretreated with and without wavelet transformation and evaluated with respect to performance. Principal component transformation was used to compress the two-way data images prior to classification. Jet fuel samples were successfully classified with 99.8 ± 0.5% accuracy for both with and without wavelet compression. Ten bootstrapped Latin partitions were used to validate the generalized prediction accuracy. Optimized partial least squares (o-PLS) regression results were used as positively biased references for comparing the FuRES prediction results. The prediction results for the jet fuel samples obtained with these two methods were compared statistically. The projected difference resolution (PDR) method was also used to evaluate the fast GC and fast MS data. Two batches of aliquots of ten new samples were prepared and run independently 4 days apart to evaluate the robustness of the method. The only change in classification parameters was the use of polynomial retention time alignment to correct for drift that occurred during the 4-day span of the two collections. FuRES achieved perfect classifications for four models of uncompressed three-way data. This fast GC/fast MS method furnishes characteristics of high speed, accuracy, and robustness. This mode of measurement may be useful as a monitoring tool to track changes in the chemical composition of fuels that may also lead to property changes. Copyright © 2010

  4. Single-run determination of polybrominated diphenyl ethers (PBDEs) di- to deca-brominated in fish meal, fish oil and fish feed by isotope dilution: Application of automated sample purification and gas chromatography/ion trap tandem mass spectrometry (GC/ITMS)

    International Nuclear Information System (INIS)

    Blanco, Sonia Lucia; Vieites, Juan M.

    2010-01-01

    The present paper describes the application of automated cleanup and fractionation procedures of the Power Prep system (Fluid Management Systems) for the determination of polybrominated diphenyl ethers (PBDEs) in feeding stuffs and fish meal and oil. Gas chromatography (GC) separation followed by ion trap tandem mass spectrometry detection in EI mode (ITMS) allowed the analysis of di- to deca-BDEs in the samples matrices used in fish aquaculture. The method developed enabled the determination of 26 native PBDE congeners and 11 13 C 12 -labelled congeners, including deca-BDE 209, in a single-run analysis, using isotope dilution. The automated cleanup, consisting of a succession of multilayer silica and basic alumina columns previously applied by Wyrzykowska et al. (2009) in combustion flue gas, was succesfully applied in our complex matrices. The method allowed an increase in productivity, i.e. lower time was required to process samples, and simultaneous purification of several samples was achieved at a time, reducing analyst dedication and human error input. Average recoveries of 43-96% were obtained. GC/ITMS can overcome the complexity originating from the sample matrix, eliminating matrix effects by tandem MS, to enable the detection of congeners penta- to nona-BDEs where interferent masses were present. The provisional detection limits, estimated in the samples, were 5-30 pg for di-, tri-, tetra-, and penta-BDEs, 20-65 pg for hexa-, hepta-, octa- and nona-BDEs, and 105 pg for deca-BDE. Reduction of deca-BDE 209 blank values is of concern to ongoing research. Good accuracy was obtained by application of the whole procedure, representing an efficient, low-cost and fast alternative for routine analyses.

  5. Liquid chromatography coupled with time-of-flight and ion trap mass spectrometry for qualitative analysis of herbal medicines

    Directory of Open Access Journals (Sweden)

    Xiao-Fei Chen

    2011-11-01

    Full Text Available With the expansion of herbal medicine (HM market, the issue on how to apply up-to-date analytical tools on qualitative analysis of HMs to assure their quality, safety and efficacy has been arousing great attention. Due to its inherent characteristics of accurate mass measurements and multiple stages analysis, the integrated strategy of liquid chromatography (LC coupled with time-of-flight mass spectrometry (TOF-MS and ion trap mass spectrometry (IT-MS is well-suited to be performed as qualitative analysis tool in this field. The purpose of this review is to provide an overview on the potential of this integrated strategy, including the review of general features of LC-IT-MS and LC-TOF-MS, the advantages of their combination, the common procedures for structure elucidation, the potential of LC-hybrid-IT-TOF/MS and also the summary and discussion of the applications of the integrated strategy for HM qualitative analysis (2006–2011. The advantages and future developments of LC coupled with IT and TOF-MS are highlighted. Keywords: High-performance liquid chromatography (HPLC, Time-of-flight mass spectrometry (TOF-MS, Ion trap mass spectrometry (IT-MS, Herbal medicine (HM

  6. An improved thin-layer chromatography/mass spectrometry coupling using a surface sampling probe electrospray ion trap system

    Energy Technology Data Exchange (ETDEWEB)

    Ford, Michael J [ORNL; Van Berkel, Gary J [ORNL

    2004-01-01

    A combined surface sampling probe/electrospray emitter coupled with an ion trap mass spectrometer was used for the direct read out of unmodified reversed-phase C18 thin-layer chromatography (TLC) plates. The operation of the surface sampling electrospray ionization interface in positive and negative ionization modes was demonstrated through the direct analysis of TLC plates on which a commercial test mix comprised of four dye compounds viz., rhodamine B, fluorescein, naphthol blue black, and fast green FCF, and an extract of the caffeine-containing plant Ilex vomitoria, were spotted and developed. Acquisition of full-scan mass spectra and automated collection of MS/MS product ion spectra while scanning a development lane along the surface of a TLC plate demonstrated the advantages of using an ion trap in this combination. Details of the sampling system, benefits of analyzing a developed lane in both positive ion and negative ion modes, levels of detection while surface scanning, surface scan speed effects, and the utility of three-dimensional data display, are also discussed.

  7. Analysis of Disperse Dyes Using Liquid Chromatography/Linear Ion Trap Mass Spectrometry (LC/LIT-MSn) and Database Construction.

    Science.gov (United States)

    Kato, Takao; Ikeue, Takahisa; Suzuki, Yasuhiro; Handa, Makoto

    2016-01-01

    Liquid chromatography/linear ion trap mass spectrometry (LC/LIT-MS(n)) was used to construct a database of disperse dyes. Fifty-three standard dyes were subjected to LC/LIT-MS(n) and characterized based on their mass spectra (MS, MS(2), and MS(3)), values of λmax (maximum absorption wavelength in the UV-visible spectrum), and retention times. The results demonstrate that it is possible to reliably identify coexisting dyes that cannot be separated by LC or detected by diode array detection due to their low molecular absorption coefficients. In addition, the by-products included in the standard dyes were found to provide important information for the identification and discrimination of dyestuffs synthesized using different processes. The confirmation of the effectiveness of LC/LIT-MS(n) analysis in detecting small amounts of disperse dyes in this study shows its potential for use in the discrimination of dyed fibers obtained at crime scenes.

  8. Identification and quantitation of auxins in plants by liquid chromatography/electrospray ionization ion trap mass spectrometry.

    Science.gov (United States)

    Lu, Qiaomei; Zhang, Lan; Chen, Tianwen; Lu, Minghua; Ping, Tong; Chen, Guonan

    2008-08-01

    Auxin is an important phylohormone, which regulates specific physiological responses such as division, elongation and differentiation of cells. A new method using liquid chromatography/electrospray ionization ion trap mass spectrometry (LC/ESI-ITMS) has been developed for identification and quantitation of four auxins. Under the optimum conditions, four auxins (indole-3-acetic acid, indole-3-propionic acid, indole-3-butyric acid and 1-naphthylacetic acid) were completely separated and quantitated within 7 min with a minimum detection limit of 8.0 ng mL(-1) with relative standard deviations lower than 5.0%. This method also has been applied to analysis of auxins in Chinese cabbage where, even with a complicated serious background perturbation due to the natural biological matrix, the mean recoveries ranged from 77.5% to 99.8%. Finally, we discuss the MS-relevant properties of the identified auxins in detail. Copyright (c) 2008 John Wiley & Sons, Ltd.

  9. Gas Chromatography.

    Science.gov (United States)

    Cram, Stuart P.; And Others

    1980-01-01

    Selects fundamental developments in theory, methodology, and instrumentation in gas chromatography (GC). A special section reviews GC in the People's Republic of China. Over 1,000 references are cited. (CS)

  10. Simultaneous analysis of strychnine and brucine and their major metabolites by liquid chromatography-electrospray ion trap mass spectrometry.

    Science.gov (United States)

    Chen, Xueguo; Lai, Yongquan; Cai, Zongwei

    2012-04-01

    A liquid chromatography-electrospray ionization-ion trap mass spectrometry (LC-ESI-ITMS) method was developed for the simultaneous analysis of strychnine, brucine and their major metabolites. Strychnine and brucine were individually incubated with rat liver S9 fraction. The incubation samples were pooled together and analyzed with LC-ESI-ITMS in positive ion and full-scan detection mode. The calibration curves of strychnine and brucine in rat liver showed good linearity in ranges of 0.020 to 8.0 µg/mL for strychnine and 0.020 to 8.5 µg/mL for brucine. The limits of detections were both 0.008 µg/mL and the recoveries were 88.3 and 83.2% for strychnine and brucine, respectively. Two metabolites were identified as strychnine N-oxide and brucine N-oxide by comparing the molecular mass, retention time, full-scan mass spectra, tandem MS and MS(3) spectra with those of strychnine and brucine. The developed method provided high sensitivity and selectivity for the determination of poisonous alkaloids and their major metabolites and can be applied in the determination of samples in forensic and clinically toxicological cases.

  11. Application of Liquid Chromatography/Ion Trap Mass Spectrometry Technique to Determine Ergot Alkaloids in Grain Products

    Directory of Open Access Journals (Sweden)

    Krystyna Szymczyk

    2015-01-01

    Full Text Available A liquid chromatography/ion trap mass spectrometry-based method to determine six ergot alkaloids and their isomers is presented. The samples were cleaned on neutral alumina-based solid-phase extraction cartridges. The following method parameters were obtained (depending on the analyte and spiking level: method recovery from 63.0 to 104.6 %, relative standard deviation below 18 %, linear range from 1 to 325 μg/kg, linear correlation coefficient not less than 0.98. The developed analytical procedure was applied to determine the levels of ergot alkaloids in 65 samples of selected rye-based food products (flour– 34 samples, bran – 12 samples, rye – 18 samples, flakes – 1 sample. Measurable levels of alkaloids were found in majority of the analysed samples, particularly in rye flour. Additionally, alkaloids were determined in ergot sclerotia isolated from rye grains. Total content was nearly 0.01 % (97.9 mg/kg. However, the alkaloid profi le was dominated by ergocristine at 45.6 % (44.7 mg/kg, an alkaloid not commonly found in the tested food products. Ergocorninine at 0.2 % (0.2 mg/kg was the least abundant alkaloid.

  12. Application of Liquid Chromatography/Ion Trap Mass Spectrometry Technique to Determine Ergot Alkaloids in Grain Products.

    Science.gov (United States)

    Bryła, Marcin; Szymczyk, Krystyna; Jędrzejczak, Renata; Roszko, Marek

    2015-03-01

    A liquid chromatography/ion trap mass spectrometry-based method to determine six ergot alkaloids and their isomers is presented. The samples were cleaned on neutral alumina-based solid-phase extraction cartridges. The following method parameters were obtained (depending on the analyte and spiking level): method recovery from 63.0 to 104.6%, relative standard deviation below 18%, linear range from 1 to 325 µg/kg, linear correlation coefficient not less than 0.98. The developed analytical procedure was applied to determine the levels of ergot alkaloids in 65 samples of selected rye-based food products (flour - 34 samples, bran - 12 samples, rye - 18 samples, flakes - 1 sample). Measurable levels of alkaloids were found in majority of the analysed samples, particularly in rye flour. Additionally, alkaloids were determined in ergot sclerotia isolated from rye grains. Total content was nearly 0.01% (97.9 mg/kg). However, the alkaloid profile was dominated by ergocristine at 45.6% (44.7 mg/kg), an alkaloid not commonly found in the tested food products. Ergocorninine at 0.2% (0.2 mg/kg) was the least abundant alkaloid.

  13. Gas-Phase Hydrogen/Deuterium Exchange of Dinucleotides and 5′-Monophosphate Dinucleotides in a Quadrupole Ion Trap

    OpenAIRE

    Chipuk, Joseph E.; Brodbelt, Jennifer S.

    2009-01-01

    Gas-phase hydrogen/deuterium (H/D) exchange reactions of four deprotonated dinucleotides (dAA, dAG, dGA, dGG) and their 5′-monophosphate analogs (5′-dAA, 5′-dAG, 5′-dGA, 5′-dGG) with D2O were performed in a quadrupole ion trap mass spectrometer. Significant differences in the rates and extents of exchange were found when the 5′-hydroxyl group of the dinucleotides was replaced by a phosphate functionality. Extensive and nucleobase-dependent exchange occurred for the deprotonated 5′-monophospha...

  14. Systematic fragmentation patterns of archaeal intact polar lipids by high-performance liquid chromatography/electrospray ionization ion-trap mass spectrometry

    OpenAIRE

    Yoshinaga, Marcos Y.; Kellermann, Matthias Y.; Rossel, Pamela E.; Schubotz, Florence; Lipp, Julius S.; Hinrichs, Kai-Uwe

    2011-01-01

    Archaea are ubiquitous and abundant microorganisms on Earth that mediate key global biogeochemical cycles. The headgroup attached to the sn-1 position in the glycerol backbone and the ether-linked isoprenoid lipids are among the diagnostic traits that distinguish Archaea from Bacteria and Eukarya. Over the last 30 years, numerous archaeal lipids were purified and described in pure cultures. Coupled high performance liquid chromatography (HPLC) ion trap mass spectrometry (ITMS) now enables the...

  15. Investigation of Symphytum cordatum alkaloids by liquid-liquid partitioning, thin-layer chromatography and liquid chromatography-ion-trap mass spectrometry

    Energy Technology Data Exchange (ETDEWEB)

    Mroczek, Tomasz [Department of Pharmacognosy with Medicinal Plants Laboratory, Medical University, 1 Chodzki St., 20-093 Lublin (Poland)]. E-mail: tmroczek@pharmacognosy.org; Ndjoko-Ioset, Karine [Laboratoire de Pharmacognosie et Phytochimie, Ecole de Pharmacie Geneve-Lausanne, Universite de Geneve, Quai Ernest-Ansermet 30, CH-1211 Geneva 4 (Switzerland); Glowniak, Kazimierz [Department of Pharmacognosy with Medicinal Plants Laboratory, Medical University, 1 Chodzki St., 20-093 Lublin (Poland); Mietkiewicz-Capala, Agnieszka [Department of Pharmacognosy with Medicinal Plants Laboratory, Medical University, 1 Chodzki St., 20-093 Lublin (Poland); Hostettmann, Kurt [Laboratoire de Pharmacognosie et Phytochimie, Ecole de Pharmacie Geneve-Lausanne, Universite de Geneve, Quai Ernest-Ansermet 30, CH-1211 Geneva 4 (Switzerland)

    2006-05-04

    From the alkalised crude extract of Symphytum cordatum (L.) W.K. roots, pyrrolizidine alkaloids (PAs) were extracted as free tertiary bases and polar N-oxides in a merely one-step liquid-liquid partitioning (LLP) in separation funnel and subsequently pre-fractionated by preparative multiple-development (MD) thin-layer chromatography (TLC) on silica gel plates. In this way three alkaloid fractions of different polarities and retention on silica gel plates were obtained as: the most polar N-oxides of the highest retention, the tertiary bases of medium retention, and diesterified N-oxides of the lowest retention. The former fraction was reduced into free bases by sodium hydrosulfite and purified by LLP on Extrelut-NT3 cartridge. It was further analysed together with the two other fractions by high-performance liquid chromatography (HPLC)-ion-trap mass spectrometry with atmospheric pressure chemical ionization (APCI) interface on XTerra C{sub 18} column using a gradient elution. Based on MS {sup n} spectra, 18 various alkaloids have been tentatively determined for the first time in this plant as the following types of structure: echimidine-N-oxide (three diasteroisomers), 7-sarracinyl-9-viridiflorylretronecine (two diasteroisomers), echimidine (two diasteroisomers), lycopsamine (two diasteroisomers), dihydroechinatine-N-oxide, dihydroheliospathuline-N-oxide, lycopsamine-N-oxide (three diasteroisomers), 7-acetyllycopsamine-N-oxide, symphytine-N-oxide (two diasteroisomers) and 2'',3''-epoxyechiumine-N-oxide.

  16. Investigation of Symphytum cordatum alkaloids by liquid-liquid partitioning, thin-layer chromatography and liquid chromatography-ion-trap mass spectrometry

    International Nuclear Information System (INIS)

    Mroczek, Tomasz; Ndjoko-Ioset, Karine; Glowniak, Kazimierz; Mietkiewicz-Capala, Agnieszka; Hostettmann, Kurt

    2006-01-01

    From the alkalised crude extract of Symphytum cordatum (L.) W.K. roots, pyrrolizidine alkaloids (PAs) were extracted as free tertiary bases and polar N-oxides in a merely one-step liquid-liquid partitioning (LLP) in separation funnel and subsequently pre-fractionated by preparative multiple-development (MD) thin-layer chromatography (TLC) on silica gel plates. In this way three alkaloid fractions of different polarities and retention on silica gel plates were obtained as: the most polar N-oxides of the highest retention, the tertiary bases of medium retention, and diesterified N-oxides of the lowest retention. The former fraction was reduced into free bases by sodium hydrosulfite and purified by LLP on Extrelut-NT3 cartridge. It was further analysed together with the two other fractions by high-performance liquid chromatography (HPLC)-ion-trap mass spectrometry with atmospheric pressure chemical ionization (APCI) interface on XTerra C 18 column using a gradient elution. Based on MS n spectra, 18 various alkaloids have been tentatively determined for the first time in this plant as the following types of structure: echimidine-N-oxide (three diasteroisomers), 7-sarracinyl-9-viridiflorylretronecine (two diasteroisomers), echimidine (two diasteroisomers), lycopsamine (two diasteroisomers), dihydroechinatine-N-oxide, dihydroheliospathuline-N-oxide, lycopsamine-N-oxide (three diasteroisomers), 7-acetyllycopsamine-N-oxide, symphytine-N-oxide (two diasteroisomers) and 2'',3''-epoxyechiumine-N-oxide

  17. Quantification of Tetramethylenedisulfotetramine (TETS) in Various Food Matrices by Solid Phase Extraction Liquid ChromatographyIon Trap Mass Spectrometry

    Science.gov (United States)

    2017-04-01

    LIQUID CHROMATOGRAPHY–ION TRAP MASS SPECTROMETRY ECBC-TR-1450 Sue Y. Bae Li Kong RESEARCH AND TECHNOLOGY DIRECTORATE April 2017 Approved for...ADDRESS. 1. REPORT DATE (DD-MM-YYYY) XX-04-2017 2. REPORT TYPE Final 3. DATES COVERED (From - To) Mar 2012 – Jun 2012 4. TITLE AND SUBTITLE...LC–IT-MS) Consecutive reaction monitoring ( CRM ) 16. SECURITY CLASSIFICATION OF: 17. LIMITATION OF ABSTRACT UU 18. NUMBER OF PAGES 38 19a

  18. Investigation of the gas-phase hydrogen/deuterium exchange behavior of aromatic dicarboxylic acids in a quadrupole ion trap

    Science.gov (United States)

    Chipuk, Joseph E.; Brodbelt, Jennifer S.

    2007-11-01

    Gas-phase hydrogen/deuterium (H/D) exchange reactions of four deprotonated aromatic dicarboxylic acids (phthalic acid, isophthalic acid, terephthalic acid and 2,6-naphthalic acid) with D2O were performed in a quadrupole ion trap mass spectrometer. Experimental results showed significant differences in the rate and extent of exchange when the relative position of the carboxylic acid groups varied. Spontaneous and near complete exchange of one aromatic hydrogen atom occurred when the carboxylic acid groups were in the meta-position, whereas no additional exchange was observed for either the ortho- or para-isomers or for the structurally similar naphthalic acid. Computational investigations support the participation of several possible exchange mechanisms with the contribution of each relying heavily on the relative orientation of the acid moieties. A relay mechanism that bridges the deprotonation site and the labile hydrogen site appears to be responsible for the H/D exchange of not only the labile hydrogen atom of isophthalic acid, but also for the formation of a stable carbanion and corresponding subsequent exchange of one aromatic hydrogen atom. The impact of hydrogen bonding on the relay mechanism is demonstrated by the reaction of phthalic acid as the extent and rate of reaction are greatly retarded by the favorable interaction of the two carboxylic acid groups. Finally, a flip-flop mechanism is likely responsible for the exchange of both terephthalic acid and 2,6-naphthalic acid where the reactive sites are too remote for exchange via relay.

  19. [Rapid screening and confirming carcinogenic banned azo colorants in textiles by high performance liquid chromatography-linear ion trap/orbitrap high-resolution mass spectrometry].

    Science.gov (United States)

    Yun, Huan; Liu, Xin; Wang, Jing; Yan, Hua; Cui, Fengyun; Zhang, Zhaohui

    2013-09-01

    A method of high performance liquid chromatography-linear ion trap/orbitrap highresolution mass spectrometry (HPLC-LTP/Orbitrap MS) was ued to screen and confirm-banned azo colorants in textiles rapidly. The analytes were reduced to carcinogenic aromatic amines with sodium dithionite in citrate buffer solution. The reduced solution was extracted bydiatomite, and loadd onto an Acquity UPLC BEH C18 column (50 mm x 2.1 MM. 1.7 microm) with a gradient elution of methanol and 0.1% (v/v) methane acid aqueous solution, and finally detected by linear ion trap/orbitrap high-resolution mass spectrometry in positive ESI mode. In mass spectrometry method, the MS spectrum of high-resolution and the collision induced dissociation (CID) spectrum of data-dependent scan mode were used for screening analysis and conformation, respectively. The calibration curves showed a good linearity in the range of 0.05 -2.00 mg/b, and the correlation coefficients (r) were higher than 0.99. By detecting spiked samples, the limits of quantification were 0.08 mg/kg for all the residues and the recoveries were in the range of 65.5% - 111.5% with the relative standard deviations (RSDs) between 0.87% and 2.49%. The results indicate that the method is simple, rapid, sensitive and suitable for the qualitative and quantitative analysis of carcinogenic aromatic amines in textiles.

  20. Application of high-performance liquid chromatography-tandem mass spectrometry with a quadrupole/linear ion trap instrument for the analysis of pesticide residues in olive oil.

    Science.gov (United States)

    Hernando, M D; Ferrer, C; Ulaszewska, M; García-Reyes, J F; Molina-Díaz, A; Fernández-Alba, A R

    2007-11-01

    This article describes the development of an enhanced liquid chromatography-mass spectrometry (LC-MS) method for the analysis of pesticides in olive oil. One hundred pesticides belonging to different classes and that are currently used in agriculture have been included in this method. The LC-MS method was developed using a hybrid quadrupole/linear ion trap (QqQ(LIT)) analyzer. Key features of this technique are the rapid scan acquisition times, high specificity and high sensitivity it enables when the multiple reaction monitoring (MRM) mode or the linear ion-trap operational mode is employed. The application of 5 ms dwell times using a linearly accelerating (LINAC) high-pressure collision cell enabled the analysis of a high number of pesticides, with enough data points acquired for optimal peak definition in MRM operation mode and for satisfactory quantitative determinations to be made. The method quantifies over a linear dynamic range of LOQs (0.03-10 microg kg(-1)) up to 500 microg kg(-1). Matrix effects were evaluated by comparing the slopes of matrix-matched and solvent-based calibration curves. Weak suppression or enhancement of signals was observed (ion (EPI) and MS3 were developed.

  1. Rapid Quantification of Four Anthocyanins in Red Grape Wine by Hydrophilic Interaction Liquid Chromatography/Triple Quadrupole Linear Ion Trap Mass Spectrometry.

    Science.gov (United States)

    Sun, Yongming; Xia, Biqi; Chen, Xiangzhun; Duanmu, Chuansong; Li, Denghao; Han, Chao

    2015-01-01

    The identification and quantification of four anthocyanins (cyanidin-3-O-glucoside, peonidin-3-O-glucoside, delphinidin-3-O-glucoside, and malvidin-3-O-glucoside) in red grape wine were carried out by hydrophilic interaction liquid chromatography/triple quadrupole linear ion trap MS (HILIC/QTrap-MS/MS). Samples were diluted directly and separated on a Merck ZIC HILIC column with 20 mM ammonium acetate solution-acetonitrile mobile phase. Quantitative data acquisition was carried out in the multiple reaction monitoring mode. Additional identification and confirmation of target compounds were performed using the enhanced product ion mode of the linear ion trap. The LOQs were in the range 0.05-1.0 ng/mL. The average recoveries were in the range 94.6 to 104.5%. The HILIC/QTrap-MS/MS platform offers the best sensitivity and specificity for characterization and quantitative determination of the four anthocyanins in red grape wines and fulfills the quality criteria for routine laboratory application.

  2. Gas-phase hydrogen/deuterium exchange of dinucleotides and 5'-monophosphate dinucleotides in a quadrupole ion trap

    Science.gov (United States)

    Chipuk, Joseph E.; Brodbelt, Jennifer S.

    2009-10-01

    Gas-phase hydrogen/deuterium (H/D) exchange reactions of four deprotonated dinucleotides (dAA, dAG, dGA, dGG) and their 5'-monophosphate analogs (5'-dAA, 5'-dAG, 5'-dGA, 5'-dGG) with D2O were performed in a quadrupole ion trap mass spectrometer. Significant differences in the rates and extents of exchange were found when the 5'-hydroxyl group of the dinucleotides was replaced by a phosphate functionality. Extensive and nucleobase-dependent exchange occurred for the deprotonated 5'-monophosphate dinucleotides, whereas the dinucleotides all exhibited essentially the same limited exchange. Results for the isomeric 5'-monophosphates, 5'-dAG and 5'-dGA, were remarkably different, indicating that the H/D exchange reaction was sequence dependent. An elaborate array of computations was performed to investigate the gas-phase structures of the ions individually and also as participants in ion-molecule complexes with D2O. Integration of the experimental and theoretical results supports a relay exchange mechanism and suggests that the exchange behavior depends highly on the identity and sequence of the nucleobases as well as their ability to interact with the deprotonation site. Finally, a shuttling mechanism is proposed to possibly account for the bimodal H/D exchange behavior observed for deprotonated 5'P-dGA. In this case, hydrogen bonding between the nucleobases in concert with interaction from the deuterating agent creates an ion-molecule complex in which hydrogen and deuterium atoms may be shuttled amongst the hydrogen-bonded participants.

  3. Rapid screening and identification of multi-class substances of very high concern in textiles using liquid chromatography-hybrid linear ion trap orbitrap mass spectrometry.

    Science.gov (United States)

    Zhang, Li; Luo, Xin; Niu, Zengyuan; Ye, Xiwen; Tang, Zhixu; Yao, Peng

    2015-03-20

    A new analytical method was established and validated for the analysis of 19 substances of very high concern (SVHCs) in textiles, including phthalic acid esters (PAEs), organotins (OTs), perfluorochemicals (PFCs) and flame retardants (FRs). After ultrasonic extraction in methanol, the textile samples were analyzed by high performance liquid chromatography-hybrid linear ion trap Orbitrap high resolution mass spectrometry (HPLC-LTQ/Orbitrap). The values of LOQ were in the range of 2-200mg/kg. Recoveries at two levels (at the LOQ and at half the limit of regulation) ranged from 68% to 120%, and the repeatability was lower than 13%. This method was successfully applied to the screening of SVHCs in commercial textile samples and is useful for the fast screening of various SVHCs. Copyright © 2015 Elsevier B.V. All rights reserved.

  4. Rapid identification and quantitation of compounds with forensic interest using fast liquid chromatography-ion trap mass spectrometry and library searching.

    Science.gov (United States)

    Pihlainen, Katja; Sippola, Erkki; Kostiainen, Risto

    2003-04-25

    A fast liquid chromatography-electrospray tandem mass spectrometric (LC-ESI-MS-MS) method by using a monolithic column, gradient elution and ion trap mass spectrometer was developed for 14 forensically interesting and chemically different compounds. All compounds were eluted within 2.5 min and the total analysis time was 5 min including stabilisation time required for the next injection. All the compounds, basics, neutrals and acids were efficiently ionised by positive ion ESI. A laboratory library including MS-MS spectra and retention times was developed and tested. Results with 476 standard samples and 50 authentic samples showed that the compounds studied can be unambiguously identified with the library. A quantitative method was developed for the compounds using external calibration. The evaluation process showed good linearity of the method and reasonable repeatability. Limits of detection ranged from 10.0 to 50.0 ng/ml.

  5. Profiling of phenolic constituents in Polygonum multiflorum Thunb. by combination of ultra-high-pressure liquid chromatography with linear ion trap-Orbitrap mass spectrometry.

    Science.gov (United States)

    Qiu, Xiaohui; Zhang, Jing; Huang, Zhihai; Zhu, Dayuan; Xu, Wen

    2013-05-31

    A simple and effective method was developed for characterization of phenolic constituents in the roots of Polygonum multiflorum by combination of ultra-high-pressure liquid chromatography with linear ion trap-Orbitrap tandem mass spectrometry (UHPLC-LTQ-Orbitrap). Stilbenes, anthraquinones, tannins and naphthalenes were differentiated by diagnostic fragment ions with accurate mass measurements and characteristic fragmentation pathways. Based on the proposed strategy, fifty-nine constituents were characterized or tentatively identified, of which twenty-two constituents were the first to be reported in P. multiflorum and twelve compounds were characterized as potential new compounds. The identification and structure elucidation of these chemicals provided essential data for further phytochemical studies and quality control of P. multiflorum. The results also demonstrated that our novel method can be extended to screen and characterize other phenolic constituents and their metabolites in botanical extracts. Copyright © 2012 Elsevier B.V. All rights reserved.

  6. Direct Analysis of Organic Compounds in Liquid Using a Miniature Photoionization Ion Trap Mass Spectrometer with Pulsed Carrier-Gas Capillary Inlet.

    Science.gov (United States)

    Lu, Xinqiong; Yu, Quan; Zhang, Qian; Ni, Kai; Qian, Xiang; Tang, Fei; Wang, Xiaohao

    2017-08-01

    A miniature ion trap mass spectrometer with capillary direct sampling and vacuum ultraviolet photoionization source was developed to conduct trace analysis of organic compounds in liquids. Self-aspiration sampling is available where the samples are drawn into the vacuum chamber through a capillary with an extremely low flow rate (less than 1 μL/min), which minimizes sample consumption in each analysis to tens of micrograms. A pulsed gas-assisted inlet was designed and optimized to promote sample transmission in the tube and facilitate the cooling of ions, thereby improving instrument sensitivity. A limit of detection of 2 ppb could be achieved for 2,4-dimethylaniline in a methanol solution. The sampling system described in the present study is specifically suitable for a miniature photoionization ion trap mass spectrometer that can perform rapid and online analysis for liquid samples. Graphical Abstract ᅟ.

  7. Ion Trap Quantum Computing

    Science.gov (United States)

    2011-12-01

    stored ions,” Adv. Atom Mol. Phys., vol. Volume 3, pp. 53–72 1968. [48] P. H. Dawson, Quadrupole Mass Spectometry and Its Applications, Melville, NY... DATE December 2011 3. REPORT TYPE AND DATES COVERED Master’s Thesis 4. TITLE AND SUBTITLE Ion trap Quantum Computing 5. FUNDING NUMBERS 6...researcher [30] that introduced the concept of ion traps in the 1950s. His experiments focused on separating atoms with different masses in order to

  8. Quantification of urinary 0,0'-dityrosine, a biomarker for oxidative damage to proteins, by high performance liquid chromatography with triple quadrupole tandem mas spectrometry. A comparison with ion-trap tandem mass spectrometry.

    NARCIS (Netherlands)

    Orhan, H.; Coolen, S.; Meerman, J.H.N.

    2005-01-01

    We recently described an isotope dilution reversed-phase liquid chromatography-atmospheric pressure chemical ionization-ion-trap-tandem mass spectrometry (HPLC-APCI-MS/MS) method for the quantitative determination of oxidized amino acids in human urine, including o,o′-dityrosine, a specific marker

  9. Multi-mycotoxin Analysis of Finished Grain and Nut Products Using Ultrahigh-Performance Liquid Chromatography and Positive Electrospray Ionization-Quadrupole Orbital Ion Trap High-Resolution Mass Spectrometry.

    Science.gov (United States)

    Liao, Chia-Ding; Wong, Jon W; Zhang, Kai; Yang, Paul; Wittenberg, James B; Trucksess, Mary W; Hayward, Douglas G; Lee, Nathaniel S; Chang, James S

    2015-09-23

    Ultrahigh-performance liquid chromatography using positive electrospray ionization and quadrupole orbital ion trap high-resolution mass spectrometry was evaluated for analyzing mycotoxins in finished cereal and nut products. Optimizing the orbital ion trap mass analyzer in full-scan mode using mycotoxin-fortified matrix extracts gave mass accuracies, δM, of aflatoxin B1 in peanut and almond) to 1175 μg/kg (fumonisin B1 in corn flour) were found in 35 of the 70 commercial grain and nut samples surveyed. Mycotoxins could be identified at δM nut products.

  10. 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.

  11. Screening of Carotenoids in Tomato Fruits by Using Liquid Chromatography with Diode Array-Linear Ion Trap Mass Spectrometry Detection.

    Science.gov (United States)

    Gentili, Alessandra; Caretti, Fulvia; Ventura, Salvatore; Pérez-Fernández, Virginia; Venditti, Alessandro; Curini, Roberta

    2015-08-26

    This paper presents an analytical strategy for a large-scale screening of carotenoids in tomato fruits by exploiting the potentialities of the triple quadrupole-linear ion trap hybrid mass spectrometer (QqQLIT). The method involves separation on C30 reversed-phase column and identification by means of diode array detection (DAD) and atmospheric pressure chemical ionization-mass spectrometry (APCI-MS). The authentic standards of six model compounds were used to optimize the separative conditions and to predict the chromatographic behavior of untargeted carotenoids. An information dependent acquisition (IDA) was performed with (i) enhanced-mass scan (EMS) as the survey scan, (ii) enhanced-resolution (ER) scan to obtain the exact mass of the precursor ions (16-35 ppm), and (iii) enhanced product ion (EPI) scan as dependent scan to obtain structural information. LC-DAD-multiple reaction monitoring (MRM) chromatograms were also acquired for the identification of targeted carotenoids occurring at low concentrations; for the first time, the relative abundance between the MRM transitions (ion ratio) was used as an extra tool for the MS distinction of structural isomers and the related families of geometrical isomers. The whole analytical strategy was high-throughput, because a great number of experimental data could be acquired with few analytical steps, and cost-effective, because only few standards were used; when applied to characterize some tomato varieties ('Tangerine', 'Pachino', 'Datterino', and 'Camone') and passata of 'San Marzano' tomatoes, our method succeeded in identifying up to 44 carotenoids in the 'Tangerine'" variety.

  12. Liquid chromatography/quadrupole ion trap/time-of-flight determination of the efficacy of drug test kits for rapid screening of food.

    Science.gov (United States)

    Zuckschwerdt, Jessica B; Nixon, Christopher E; Ciner, Frederic L; Croley, Timothy R

    2008-05-01

    The goal of this study was to evaluate the plausibility and accuracy of commercially available on-site immunoassay urinalysis kits for the screening of compounds of interest within food matrices. In conjunction with this study, a sensitive, robust, and reproducible analytical method, utilizing solid-phase extraction liquid chromatography/quadrupole ion trap/time-of-flight mass spectrometry for confirmation analysis, was developed. The food matrices analyzed were tomato juice, apple juice, milk, beer, white wine, ground beef, powdered milk, and all-purpose flour. Compounds fortified into the food matrices included heroin, phencyclidine, cocaine, benzoylecgonine, methadone, 2-ethylidene-1,5-dimethyl-3,3-diphenylpyrrolidine, imipramine, doxepin, nitrazepam, diazepam, oxazepam, temazepam, alprazolam, flunitrazepam, clonazepam, and lorazepam. Standard curves were prepared for each matrix from 10 to 500 ng/ml for each analyzed compound. All liquid chromatography/tandem mass spectrometry samples were fortified with 20 microl of deuterated internal standard at 90 ng/ml. Quality control standards were prepared at 20 and 400 ng/ml, and > 90% were within 2 SD of the mean for each analyte. The test kits were found to produce up to 85% of the expected results based on concentration levels of adulterants (i-Screen in milk). This study shows that lateral-flow immunoassay test kits are plausible as a rapid, accurate, and reliable screening method in the event of adulteration of the food supply.

  13. Quantitative determination of isoquinoline alkaloids and chlorogenic acid in Berberis species using ultra high performance liquid chromatography with hybrid triple quadrupole linear ion trap mass spectrometry.

    Science.gov (United States)

    Singh, Awantika; Bajpai, Vikas; Kumar, Sunil; Arya, Kamal Ram; Sharma, Kulwant Rai; Kumar, Brijesh

    2015-06-01

    Berberis species are well known and used extensively as medicinal plants in traditional medicine. They have many medicinal values attributable to the presence of alkaloids having different pharmacological activities. In this study, a method was developed and validated as per international conference on harmonization guidelines using ultra high performance liquid chromatography with hybrid triple quadrupole-linear ion trap mass spectrometry operated in the multiple reaction monitoring mode for nine bioactive compounds, including protoberberine alkaloids, aporphine alkaloids and chlorogenic acid. This method was applied in different plant parts of eight Berberis species to determine variations in content of nine bioactive compounds. The separation was achieved on an ACQUITY UPLC CSH™ C18 column using a gradient mobile phase at flow rate 0.3 mL/min. Calibration curves for all the nine analytes provided optimum linear detector response (with R(2) ≥0.9989) over the concentration range of 0.5-1000 ng/mL. The precision and accuracy were within RSDs ≤2.4 and ≤2.3%, respectively. The results indicated significant variation in the total contents of the nine compounds in Berberis species. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  14. Targeted liquid chromatography quadrupole ion trap mass spectrometry analysis of tachykinin related peptides reveals significant expression differences in a rat model of neuropathic pain.

    Science.gov (United States)

    Pailleux, Floriane; Vachon, Pascal; Lemoine, Jérôme; Beaudry, Francis

    2013-08-01

    Animal models are widely used to perform basic scientific research in pain. The rodent chronic constriction injury (CCI) model is widely used to study neuropathic pain. Animals were tested prior and after CCI surgery using behavioral tests (von Frey filaments and Hargreaves test) to evaluate pain. The brain and the lumbar enlargement of the spinal cord were collected from neuropathic and normal animals. Tachykinin related peptides were analyzed by high performance liquid chromatography quadrupole ion trap mass spectrometry. Our results reveal that the β-tachykinin₅₈₋₇₁, SP and SP₃₋₁₁ up-regulation are closely related to pain behavior. The spinal β-tachykinin₅₈₋₇₁, SP and SP₃₋₁₁ concentrations were significantly up-regulated in neuropathic animals compared with normal animals (ptachykinin₅₈₋₇₁ and SP concentrations were significantly up-regulated (ptachykinin₅₈₋₇₁, SP₁₋₇ and SP₆₋₁₁ (p>0.05). The β-tachykinin₅₈₋₇₁, SP and C-terminal SP metabolites could potentially serve as biomarkers in early drug discovery. Copyright © 2013 Elsevier Ltd. All rights reserved.

  15. Simultaneous determination of components released from dental composite resins in human saliva by liquid chromatography/multiple-stage ion trap mass spectrometry.

    Science.gov (United States)

    Hsu, Wei-Yi; Wang, Ven-Shing; Lai, Chien-Chen; Tsai, Fuu-Jen

    2012-02-01

    Dental composite resins are widely used for fixing teeth; however, the monomers used in dental composite resins have been found to be cytotoxic and genotoxic, namely triethylene glycol dimethacrylate (TEGDMA), urethane dimethacrylate (UDMA), and bisphenol A glycol dimethacrylate (Bis-GMA). In this study, we incubated dental composite resins with human saliva for demonstrating the released monomers and biodegradation products. A simple saliva sample dilution method without purification or derivatization was used for quantification. We found that liquid chromatography coupled with multiple-stage ion trap mass spectrometry (LC-MS(n) ) operated in selected reaction monitoring (SRM) mode was able to separate the three monomers within 10 min. The calibration curves were linear (R² >0.996) over a wide range for each monomer in saliva: TEGDMA, 5-500 ppb; UDMA, 5-100 ppb, and Bis-GMA, 5-700 ppb. Furthermore, several biodegradation products were discovered with data-dependent MS/MS scan techniques. Although TEGMA degradation products have previously been reported, we identified two previously unknown UDMA degradation products. The LC-MS/MS method developed in this study was able to successfully quantify monomers and their principal biodegradation products from dental composite resins in human saliva. Copyright © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  16. [Rapid screening and identification of 22 allergenic disperse dyes in ecological textiles by high performance liquid chromatography-linear ion trap/orbitrap mass spectrometry].

    Science.gov (United States)

    Niu, Zengyuan; Luo, Xin; Ye, Xiwen; Xiu, Xiaoli; Zhang, Li; Wang, Xin; Chen, Jing

    2015-10-01

    A rapid screening method based on high performance liquid chromatography-linear ion trap/orbitrap high-resolution mass spectrometry (HPLC-LTQ/Orbitrap MS) for 22 disperse dyes in ecological textiles has been established. The target compounds were extracted by pyridine/water (1:1, v/v) by shaking extraction in 90 degrees C water bath. The extracts were then separated by a CAPCELL PAK C18 column (100 mm x 2.0 mm, 5 μm) using gradient elution with acetonitrile-5 mmol/L ammonium acetate containing 0.01% (v/v) formic acid as mobile phases, and finally analyzed by HPLC-LTQ/Orbitrap in positive and negative ESI modes. The retention time and accurate mass of parent ion were used for fast screening of 22 disperse dyes, while the confirmatory analysis was obtained by fragments generated by collision-induced dissociation (CID) MS/MS. Target analysis exhibited high mass accuracy (textiles, and Disperse Orange 37/76 was detected in one of them. With high selectivity and strong anti-jamming ability, this method is simple, rapid, accurate, and it can be used for the inspection of disperse dyes in textiles.

  17. [Determination of free carcinogenic aromatic amines in textiles by ultra-performance liquid chromatography-linear ion trap/orbitrap high resolution mass spectrometry].

    Science.gov (United States)

    Ye, Xiwen; Peng, Yan; Niu, Zengyuan; Gao, Yonggang; Luo, Xin; Zou, Li

    2015-04-01

    A method of ultra-performance liquid chromatography-linear ion trap/orbitrap high resolution mass spectrometry (UPLC-LTQ/Orbitrap MS) was used to determine 24 free carcinogenic aromatic amines in textiles. The main factors influencing the method, including the extraction solvent, the extraction temperature and the extraction time, were optimized. Under the optimized experimental conditions, the analytes were extracted by dichloromethane for 10 min and loaded into a ZORBAX SB-C18 column (150 mm x 2.1 mm, 5 µm) with a gradient elution of methanol and 0.1% aqueous formic acid solution, and finally detected by LTQ/Orbitrap MS. The screening and quantitative analysis were carried out by the accurate mass of quasi-molecular ion and the peak in extracted chromatogram with accurate mass respectively. The correlation coefficients (R2) were higher than 0.99. The recoveries were 87.8%-105.6% with the RSDs were 1.6%-3.4%. The limits of detection were 0.5-1 µg/kg, and the limits of quantification were 1.5-3 µg/kg. The proposed method was applied to 14 textile samples containing spandex. 4,4'-Diaminodiphenylmethane was determined in five samples and the contents were 0.21-25.6 mg/kg. The results indicate that the developed method is a simple, efficient, precise and reliable technique for the determination of free carcinogenic aromatic amines in textiles.

  18. Application of ultra-high pressure liquid chromatography linear ion-trap orbitrap to qualitative and quantitative assessment of pesticide residues.

    Science.gov (United States)

    Farré, M; Picó, Y; Barceló, D

    2014-02-07

    The analysis of pesticides residues using a last generation high resolution and high mass accuracy hybrid linear ion trap-Orbitrap mass spectrometer (LTQ-Orbitrap-MS) was explored. Pesticides were extracted from fruits, fish, bees and sediments by QuEChERS and from water by solid-phase with Oasis HLB cartridges. Ultra-high pressure liquid chromatography (UHPLC)-LTQ-Orbitrap mass spectrometer acquired full scan MS data for quantification, and data dependent (dd) MS(2) and MS(3) product ion spectra for identification and/or confirmation. The regression coefficients (r(2)) for the calibration curves (two order of magnitude up to the lowest calibration level) in the study were ≥0.99. The LODs for 54 validated compounds were ≤2ngmL(-1) (analytical standards). The relative standard deviation (RSD), which was used to estimate precision, was always lower than 22%. The recovery of extraction and matrix effects ranged from 58 to 120% and from -92 to 52%, respectively. Mass accuracy was always ≤4ppm, corresponding to a maximum mass error of 1.6millimass units (mmu). This procedure was then successfully applied to pesticide residues in a set of the above-mentioned food and environmental samples. In addition to target analytes, this method enables the simultaneous detection/identification of non-target pesticides, pharmaceuticals, drugs of abuse, mycotoxins, and their metabolites. Copyright © 2013 Elsevier B.V. All rights reserved.

  19. Application of High-Performance Liquid Chromatography Coupled with Linear Ion Trap Quadrupole Orbitrap Mass Spectrometry for Qualitative and Quantitative Assessment of Shejin-Liyan Granule Supplements.

    Science.gov (United States)

    Gu, Jifeng; Wu, Weijun; Huang, Mengwei; Long, Fen; Liu, Xinhua; Zhu, Yizhun

    2018-04-11

    A method for high-performance liquid chromatography coupled with linear ion trap quadrupole Orbitrap high-resolution mass spectrometry (HPLC-LTQ-Orbitrap MS) was developed and validated for the qualitative and quantitative assessment of Shejin-liyan Granule. According to the fragmentation mechanism and high-resolution MS data, 54 compounds, including fourteen isoflavones, eleven ligands, eight flavonoids, six physalins, six organic acids, four triterpenoid saponins, two xanthones, two alkaloids, and one licorice coumarin, were identified or tentatively characterized. In addition, ten of the representative compounds (matrine, galuteolin, tectoridin, iridin, arctiin, tectorigenin, glycyrrhizic acid, irigenin, arctigenin, and irisflorentin) were quantified using the validated HPLC-LTQ-Orbitrap MS method. The method validation showed a good linearity with coefficients of determination (r²) above 0.9914 for all analytes. The accuracy of the intra- and inter-day variation of the investigated compounds was 95.0-105.0%, and the precision values were less than 4.89%. The mean recoveries and reproducibilities of each analyte were 95.1-104.8%, with relative standard deviations below 4.91%. The method successfully quantified the ten compounds in Shejin-liyan Granule, and the results show that the method is accurate, sensitive, and reliable.

  20. Application of High-Performance Liquid Chromatography Coupled with Linear Ion Trap Quadrupole Orbitrap Mass Spectrometry for Qualitative and Quantitative Assessment of Shejin-Liyan Granule Supplements

    Directory of Open Access Journals (Sweden)

    Jifeng Gu

    2018-04-01

    Full Text Available A method for high-performance liquid chromatography coupled with linear ion trap quadrupole Orbitrap high-resolution mass spectrometry (HPLC-LTQ-Orbitrap MS was developed and validated for the qualitative and quantitative assessment of Shejin-liyan Granule. According to the fragmentation mechanism and high-resolution MS data, 54 compounds, including fourteen isoflavones, eleven ligands, eight flavonoids, six physalins, six organic acids, four triterpenoid saponins, two xanthones, two alkaloids, and one licorice coumarin, were identified or tentatively characterized. In addition, ten of the representative compounds (matrine, galuteolin, tectoridin, iridin, arctiin, tectorigenin, glycyrrhizic acid, irigenin, arctigenin, and irisflorentin were quantified using the validated HPLC-LTQ-Orbitrap MS method. The method validation showed a good linearity with coefficients of determination (r2 above 0.9914 for all analytes. The accuracy of the intra- and inter-day variation of the investigated compounds was 95.0–105.0%, and the precision values were less than 4.89%. The mean recoveries and reproducibilities of each analyte were 95.1–104.8%, with relative standard deviations below 4.91%. The method successfully quantified the ten compounds in Shejin-liyan Granule, and the results show that the method is accurate, sensitive, and reliable.

  1. A practical strategy for the characterization of coumarins in Radix Glehniae by liquid chromatography coupled with triple quadrupole-linear ion trap mass spectrometry.

    Science.gov (United States)

    Yang, Wei; Ye, Min; Liu, Man; Kong, Dezhi; Shi, Rui; Shi, Xiaowei; Zhang, Kerong; Wang, Qiao; Lantong, Zhang

    2010-07-02

    The aim of the present study was to develop a practical method for the characterization of coumarins in Radix Glehniae by liquid chromatography-mass spectrometry (LC-MS). First, 10 coumarin standards (including two pairs of isomers) were studied, and mass spectrometry fragmentation patterns and elution time rules for the coumarins were found. Then, an extract of Radix Glehniae was analyzed by the combination of two scan modes, i.e., multiple ion monitoring-information-dependent acquisition-enhanced product ion mode (MIM-IDA-EPI) and precursor scan information-dependent acquisition-enhanced product ion mode (PREC-IDA-EPI) on a hybrid triple quadrupole-linear ion trap mass spectrometer. A total of 41 coumarins were identified on the basis of their mass spectrometry fragmentation patterns. This is the first time that these two scan modes have been combined to characterize chemical constituents in traditional Chinese medicine. This new method allowed the identification of coumarins in Radix Glehniae in trace amounts. The methodology proposed in this study could be valuable for the structural characterization of coumarins from complex natural and synthetic sources. Copyright 2010 Elsevier B.V. All rights reserved.

  2. [Screening and confirmation of 24 hormones in cosmetics by ultra high performance liquid chromatography-linear ion trap/orbitrap high resolution mass spectrometry].

    Science.gov (United States)

    Li, Zhaoyong; Wang, Fengmei; Niu, Zengyuan; Luo, Xin; Zhang, Gang; Chen, Junhui

    2014-05-01

    A method of ultra high performance liquid chromatography-linear ion trap/orbitrap high resolution mass spectrometry (UPLC-LTQ/Orbitrap MS) was established to screen and confirm 24 hormones in cosmetics. Various cosmetic samples were extracted with methanol. The extract was loaded onto a Waters ACQUITY UPLC BEH C18 column (50 mm x 2.1 mm, 1.7 microm) using a gradient elution of acetonitrile/water containing 0.1% (v/v) formic acid for the separation. The accurate mass of quasi-molecular ion was acquired by full scanning of electrostatic field orbitrap. The rapid screening was carried out by the accurate mass of quasi-molecular ion. The confirmation analysis for targeted compounds was performed with the retention time and qualitative fragments obtained by data dependent scan mode. Under the optimal conditions, the 24 hormones were routinely detected with mass accuracy error below 3 x 10(-6) (3 ppm), and good linearities were obtained in their respective linear ranges with correlation coefficients higher than 0.99. The LODs (S/N = 3) of the 24 compounds were hormones in 50 cosmetic samples. The results demonstrate that the method is a useful tool for the rapid screening and identification of the hormones in cosmetics.

  3. Simultaneous identification and quantification of tetrodotoxin in fresh pufferfish and pufferfish-based products using immunoaffinity columns and liquid chromatography/quadrupole-linear ion trap mass spectrometry

    Science.gov (United States)

    Guo, Mengmeng; Wu, Haiyan; Jiang, Tao; Tan, Zhijun; Zhao, Chunxia; Zheng, Guanchao; Li, Zhaoxin; Zhai, Yuxiu

    2017-07-01

    In this study, we established a comprehensive method for simultaneous identification and quantification of tetrodotoxin (TTX) in fresh pufferfish tissues and pufferfish-based products using liquid chromatography/quadrupole-linear ion trap mass spectrometry (LC-QqLIT-MS). TTX was extracted by 1% acetic acid-methanol, and most of the lipids were then removed by freezing lipid precipitation, followed by purification and concentration using immunoaffinity columns (IACs). Matrix effects were substantially reduced due to the high specificity of the IACs, and thus, background interference was avoided. Quantitation analysis was therefore performed using an external calibration curve with standards prepared in mobile phase. The method was evaluated by fortifying samples at 1, 10, and 100 ng/g, respectively, and the recoveries ranged from 75.8%-107%, with a relative standard deviation of less than 15%. The TTX calibration curves were linear over the range of 1-1 000 μg/L, with a detection limit of 0.3 ng/g and a quantification limit of 1 ng/g. Using this method, samples can be further analyzed using an information-dependent acquisition (IDA) experiment, in the positive mode, from a single liquid chromatography-tandem mass spectrometry injection, which can provide an extra level of confirmation by matching the full product ion spectra acquired for a standard sample with those from an enhanced product ion (EPI) library. The scheduled multiple reaction monitoring method enabled TTX to be screened for, and TTX was positively identified using the IDA and EPI spectra. This method was successfully applied to analyze a total of 206 samples of fresh pufferfish tissues and pufferfish-based products. The results from this study show that the proposed method can be used to quantify and identify TTX in a single run with excellent sensitivity and reproducibility, and is suitable for the analysis of complex matrix pufferfish samples.

  4. Ultrahigh-performance liquid chromatography/electrospray ionization linear ion trap Orbitrap mass spectrometry of antioxidants (amines and phenols) applied in lubricant engineering.

    Science.gov (United States)

    Kassler, Alexander; Pittenauer, Ernst; Doerr, Nicole; Allmaier, Guenter

    2014-01-15

    For the qualification and quantification of antioxidants (aromatic amines and sterically hindered phenols), most of them applied as lubricant additives, two ultrahigh-performance liquid chromatography (UHPLC) electrospray ionization mass spectrometric methods applying the positive and negative ion mode have been developed for lubricant design and engineering thus allowing e.g. the study of the degradation of lubricants. Based on the different chemical properties of the two groups of antioxidants, two methods offering a fast separation (10 min) without prior derivatization were developed. In order to reach these requirements, UHPLC was coupled with an LTQ Orbitrap hybrid tandem mass spectrometer with positive and negative ion electrospray ionization for simultaneous detection of spectra from UHPLC-high-resolution (HR)-MS (full scan mode) and UHPLC-low-resolution linear ion trap MS(2) (LITMS(2)), which we term UHPLC/HRMS-LITMS(2). All 20 analytes investigated could be qualified by an UHPLC/HRMS-LITMS(2) approach consisting of simultaneous UHPLC/HRMS (elemental composition) and UHPLC/LITMS(2) (diagnostic product ions) according to EC guidelines. Quantification was based on an UHPLC/LITMS(2) approach due to increased sensitivity and selectivity compared to UHPLC/HRMS. Absolute quantification was only feasible for seven analytes with well-specified purity of references whereas relative quantification was obtainable for another nine antioxidants. All of them showed good standard deviation and repeatability. The combined methods allow qualitative and quantitative determination of a wide variety of different antioxidants including aminic/phenolic compounds applied in lubricant engineering. These data show that the developed methods will be versatile tools for further research on identification and characterization of the thermo-oxidative degradation products of antioxidants in lubricants. Copyright © 2013 John Wiley & Sons, Ltd.

  5. Development of a method for comprehensive and quantitative analysis of plant hormones by highly sensitive nanoflow liquid chromatography-electrospray ionization-ion trap mass spectrometry

    Energy Technology Data Exchange (ETDEWEB)

    Izumi, Yoshihiro; Okazawa, Atsushi; Bamba, Takeshi; Kobayashi, Akio [Department of Biotechnology, Graduate School of Engineering, Osaka University, 2-1 Yamadaoka, Suita, Osaka 565-0871 (Japan); Fukusaki, Eiichiro, E-mail: fukusaki@bio.eng.osaka-u.ac.jp [Department of Biotechnology, Graduate School of Engineering, Osaka University, 2-1 Yamadaoka, Suita, Osaka 565-0871 (Japan)

    2009-08-26

    In recent plant hormone research, there is an increased demand for a highly sensitive and comprehensive analytical approach to elucidate the hormonal signaling networks, functions, and dynamics. We have demonstrated the high sensitivity of a comprehensive and quantitative analytical method developed with nanoflow liquid chromatography-electrospray ionization-ion trap mass spectrometry (LC-ESI-IT-MS/MS) under multiple-reaction monitoring (MRM) in plant hormone profiling. Unlabeled and deuterium-labeled isotopomers of four classes of plant hormones and their derivatives, auxins, cytokinins (CK), abscisic acid (ABA), and gibberellins (GA), were analyzed by this method. The optimized nanoflow-LC-ESI-IT-MS/MS method showed ca. 5-10-fold greater sensitivity than capillary-LC-ESI-IT-MS/MS, and the detection limits (S/N = 3) of several plant hormones were in the sub-fmol range. The results showed excellent linearity (R{sup 2} values of 0.9937-1.0000) and reproducibility of elution times (relative standard deviations, RSDs, <1.1%) and peak areas (RSDs, <10.7%) for all target compounds. Further, sample purification using Oasis HLB and Oasis MCX cartridges significantly decreased the ion-suppressing effects of biological matrix as compared to the purification using only Oasis HLB cartridge. The optimized nanoflow-LC-ESI-IT-MS/MS method was successfully used to analyze endogenous plant hormones in Arabidopsis and tobacco samples. The samples used in this analysis were extracted from only 17 tobacco dry seeds (1 mg DW), indicating that the efficiency of analysis of endogenous plant hormones strongly depends on the detection sensitivity of the method. Our analytical approach will be useful for in-depth studies on complex plant hormonal metabolism.

  6. Structural elucidation of biologically active neomycin N-octyl derivatives in a regioisomeric mixture by means of liquid chromatography/ion trap time-of-flight mass spectrometry

    NARCIS (Netherlands)

    Giera, M.; de Vlieger, J.S.B.; Lingeman, H.; Irth, H.; Niessen, W.M.A.

    2010-01-01

    Structural elucidation of six regioisomers of mono-N-octyl derivatized neomycin is achieved using MSn (up to n1/4 4) on an ion trap time-of-flight (IT-TOF) instrument equipped with electrospray ionization. The mixture of six derivatized neomycin analogues was generated by reductive amination in a

  7. Cryogenic surface ion traps

    International Nuclear Information System (INIS)

    Niedermayr, M.

    2015-01-01

    Microfabricated surface traps are a promising architecture to realize a scalable quantum computer based on trapped ions. In principle, hundreds or thousands of surface traps can be located on a single substrate in order to provide large arrays of interacting ions. To this end, trap designs and fabrication methods are required that provide scalable, stable and reproducible ion traps. This work presents a novel surface-trap design developed for cryogenic applications. Intrinsic silicon is used as the substrate material of the traps. The well-developed microfabrication and structuring methods of silicon are utilized to create simple and reproducible traps. The traps were tested and characterized in a cryogenic setup. Ions could be trapped and their life time and motional heating were investigated. Long ion lifetimes of several hours were observed and the measured heating rates were reproducibly low at around 1 phonon per second at a trap frequency of 1 MHz. (author) [de

  8. Gas chromatography in space

    Science.gov (United States)

    Akapo, S. O.; Dimandja, J. M.; Kojiro, D. R.; Valentin, J. R.; Carle, G. C.

    1999-01-01

    Gas chromatography has proven to be a very useful analytical technique for in situ analysis of extraterrestrial environments as demonstrated by its successful operation on spacecraft missions to Mars and Venus. The technique is also one of the six scientific instruments aboard the Huygens probe to explore Titan's atmosphere and surface. A review of gas chromatography in previous space missions and some recent developments in the current environment of fiscal constraints and payload size limitations are presented.

  9. Gas-phase hydrogen/deuterium exchange of 5'- and 3'-mononucleotides in a quadrupole ion trap: exploring the role of conformation and system energy.

    Science.gov (United States)

    Chipuk, Joseph E; Brodbelt, Jennifer S

    2007-04-01

    Gas-phase hydrogen/deuterium (H/D) exchange reactions for deprotonated 2'-deoxy-5'-monophosphate and 2'-deoxy-3'-monophosphate nucleotides with D(2)O were performed in a quadrupole ion trap mass spectrometer. To augment these experiments, molecular modeling was also conducted to identify likely deprotonation sites and potential gas-phase conformations of the anions. A majority of the 5'-monophosphates exchanged extensively with several of the compounds completely incorporating deuterium in place of their labile hydrogen atoms. In contrast, most of the 3'-monophosphate isomers exchanged relatively few hydrogen atoms, even though the rate of the first two exchanges was greater than observed for the 5'-monophosphates. Mononucleotides that failed to incorporate more than two deuterium atoms under default reaction conditions were often found to exchange more extensively when reactions were performed under higher energy conditions. Integration of the experimental and theoretical results supports the use of a relay exchange mechanism and suggests that the exchange behavior depends highly on the identity and orientation of the nucleobase and the position and flexibility of the deprotonated phosphate moiety. These observations also highlight the importance of the distance between the various participating groups in addition to their gas-phase acidity and basicity.

  10. The quantitation of 2-oxo-3-hydroxy lysergic acid diethylamide (O-H-LSD) in human urine specimens, a metabolite of LSD: comparative analysis using liquid chromatography-selected ion monitoring mass spectrometry and liquid chromatography-ion trap mass spectrometry.

    Science.gov (United States)

    Poch, G K; Klette, K L; Anderson, C

    2000-04-01

    This paper compares the potential forensic application of two sensitive and rapid procedures (liquid chromatography-mass spectrometry and liquid chromatography-ion trap mass spectrometry) for the detection and quantitation of 2-oxo-3-hydroxy lysergic acid diethylamide (O-H-LSD) a major LSD metabolite. O-H-LSD calibration curves for both procedures were linear over the concentration range 0-8,000 pg/mL with correlation coefficients (r2) greater than 0.99. The observed limit of detection (LOD) and limit of quantitation (LOQ) for O-H-LSD in both procedures was 400 pg/mL. Sixty-eight human urine specimens that had previously been found to contain LSD by gas chromatography-mass spectrometry were reanalyzed by both procedures for LSD and O-H-LSD. These specimens contained a mean concentration of O-H-LSD approximately 16 times higher than the LSD concentration. Because both LC methods produce similar results, either procedure can be readily adapted to O-H-LSD analysis for use in high-volume drug-testing laboratories. In addition, the possibility of significantly increasing the LSD detection time window by targeting this major LSD metabolite for analysis may influence other drug-free workplace programs to test for LSD.

  11. Determination of ifosfamide, 2-and 3-dechloroethyifosfamide using gas chromatography with nitrogen-phosphorus or mass spectrometry detection

    NARCIS (Netherlands)

    Kerbusch, T; Jeuken, MJ; Derraz, J; van Putten, JWG; Huitema, ADR; Beijnen, JH

    2000-01-01

    A comparison was made between methods for determining ifosfamide (IF), 2- (2DCE) and 3-dechloroethylifosfamide (3DCE) using gas chromatography with nitrogen-phosphorus detection (GC-NPD) versus positive ion electron-impact ion-trap mass spectrometry (GC-MS'). Sample pretreatment involved

  12. Quantification of Biogenic and Anthropogenic Hydrocarbons using a Commercial Gas Chromatograph - Ion Trap Mass Spectrometer at a Ground Site near Fort McKay, AB

    Science.gov (United States)

    Tokarek, T. W.; Osthoff, H. D.

    2014-12-01

    The extraction of fossil fuels from the Alberta oil sands has been the focus of considerable attention due to its association with sizeable emissions of a variety of atmospheric pollutants, the magnitude and impacts of which are currently poorly constrained by observations. In order to more reliably estimate the magnitude and impact of these emissions, an intensive air quality measurement campaign, called "Fort McMurray Oil Sands Strategic Investigation of Local Sources" (FOSSILS), was conducted in the summer of 2013 as part of the Alberta-Canada joint oil sands monitoring program (JOSM) to identify and quantify emissions and their transformations from the Alberta oil sands. The challenge is that the region is surrounded by boreal forest, which provides a substantial background of biogenic hydrocarbons during summer. In this presentation, measurements of volatile organic compounds (VOCs) at the AMS13 ground site near Fort McKay, Alberta, from Aug 17 to Sept 6, 2013 using a commercial Griffin 450 gas chromatograph equipped with ion trap mass spectrometric detection and Tenax preconcentration are described. The combination of retention information and electron impact mass spectral data allowed unambiguous identification and quantification of the major biogenic monoterpenes, e.g., α and β-pinene, limonene, camphene, and 3Δ-carene, and of many anthropogenically derived hydrocarbons. Mixing ratios of biogenic hydrocarbons varied with time of day, temperature, and solar radiation, with maxima typically occurring at night, rationalized by nocturnal mixing heights and low mixing ratios of the nocturnal oxidants ozone (O3) and the nitrate radical (NO3). In contrast, mixing ratios of anthropogenic VOCs, e.g., benzene, toluene, ethyl benzene, and o-, p-, and m-xylene (BTEX), strongly depended on meteorological conditions, i.e., local wind direction. During episodes with high BTEX abundance, many additional high molecular weight hydrocarbons were observed which were not

  13. Polar organic chemical integrative sampling and liquid chromatography- electrospray/ion-trap mass spectrometry for assessing selected prescription and illicit drugs in treated sewage effluents

    Science.gov (United States)

    Jones-Lepp, T. L.; Alvarez, D.A.; Petty, J.D.; Huckins, J.N.

    2004-01-01

    The purpose of the research presented in this paper was twofold: (1) to demonstrate the coupling of two state-of-the-art techniques: a time-weighted polar organic chemical integrative sampler (POCIS) and microliquid chromatography–electrospray/ion-trap mass spectrometry and (2) to assess the ability of these methodologies to detect six drugs (azithromycin, fluoxetine, omeprazole, levothyroxine, methamphetamine, methylenedioxymethamphetamine [MDMA]) in a real-world environment, e.g., waste water effluent. In the effluent from three wastewater treatment plants (WWTPs), azithromycin was detected at concentrations ranging from 15 to 66 ng/L, which is equivalent to a total annual release of 1 to 4 kg into receiving waters. Detected and confirmed in the effluent from two WWTPs were two illicit drugs, methamphetamine and MDMA, at 2 and 0.5 ng/L, respectively. Although the ecotoxicologic significance of drugs in environmental matrices, particularly water, has not been closely examined, it can only be surmised that these substances have the potential to adversely affect biota that are continuously exposed to them even at very low levels. The potential for chronic effects on human health is also unknown but of increasing concern because of the multiuse character of water, particularly in densely populated, arid areas.

  14. Metabolism of nitazoxanide in rats, pigs, and chickens: Application of liquid chromatography coupled to hybrid linear ion trap/Orbitrap mass spectrometer.

    Science.gov (United States)

    Huang, Xianhui; Guo, Chunna; Chen, Zhangliu; Liu, Yahong; He, Limin; Zeng, Zhenling; Yan, Chaoqun; Pan, Guangfang; Li, Shuaipeng

    2015-09-01

    Nitazoxanide (NTZ) is a nitrothiazole benzamide compound with a broad activity spectrum against parasites, Gram-positive and Gram-negative anaerobic bacteria, and viruses. In this study, hybrid linear ion trap/Orbitrap mass spectrometer providing a high mass resolution and accuracy was used to investigate the metabolism of NTZ in rats, pigs, and chickens. The results revealed that acetylation and glucuronidation were the main metabolic pathways in rats and pigs, whereas acetylation and sulfation were the major metabolic pathways in chickens, which indicated interspecies variations in drug metabolism and elimination. With the accurate mass data and the characteristic MS(n) product ions, we identified six metabolites in which tizoxanide and hydroxylated tizoxanide were phase I metabolites and tizoxanide glucuronide, tizoxanide glucose, tizoxanide sulfate and hydroxyl tizoxanide sulfate were phase II metabolites. Hydroxylated tizoxanide and tizoxanide glucose were identified for the first time. All the comprehensive data were provided to make out the metabolism of NTZ in rats, pigs and chickens more clearly. Copyright © 2015 Elsevier B.V. All rights reserved.

  15. High performance liquid chromatography/ion-trap mass spectrometry for separation and simultaneous determination of ethynylestradiol, gestodene, levonorgestrel, cyproterone acetate and desogestrel.

    Science.gov (United States)

    Matejícek, David; Kubán, Vlastimil

    2007-04-11

    A fast and highly sensitive high performance liquid chromatographic/ion-trap mass spectrometric method (LC/MS) has been developed for simultaneous determination of ethynylestradiol (EE2), gestodene (GES), levonorgestrel (LNG), cyproterone acetate (CPA) and desogestrel (DES). Among three types of sorbents tested (C8, C18 and phenyl) from two suppliers, the best separation was achieved on reverse phase Zorbax SB-Phenyl column using aqueous methanol as a mobile phase. A linear gradient profile from 70 up to 100% (v/v) in 7th min, kept constant at 100% up to 10th min and followed by a negative gradient to 70% of methanol up to 12th min was used for elution. Applicability of electrospray ionization (ESI) and atmospheric pressure chemical ionization (APCI) and influence of the mobile phase composition, its flow rate, capillary/vaporizer temperature of API source and in-source fragmentor voltage ionization are discussed. The on-column limits of quantification (10S/N) were 300 pg of EE2, 14 pg of GES and LNG, 4 pg of CPA and 960 pg of DES per injection (1 microL) using APCI with data collection in selected ion monitoring (SIM) mode. The analytical performance of the method was evaluated using the determination of EE2, GES, LNG, CPA and DES in contraceptives and river water samples.

  16. Trace analysis of pesticides in paddy field water by direct injection using liquid chromatography-quadrupole-linear ion trap-mass spectrometry.

    Science.gov (United States)

    Pareja, Lucía; Martínez-Bueno, M J; Cesio, Verónica; Heinzen, Horacio; Fernández-Alba, A R

    2011-07-29

    A multiresidue method was developed for the quantification and confirmation of 70 pesticides in paddy field water. After its filtration, water was injected directly in a liquid chromatograph coupled to a hybrid triple quadrupole-linear ion trap-mass spectrometer (QqLIT). The list of target analytes included organophosphates, phenylureas, sulfonylureas, carbamates, conazoles, imidazolinones and others compounds widely used in different countries where rice is cropped. Detection and quantification limits achieved were in the range from 0.4 to 80 ng L(-1) and from 2 to 150 ng L(-1), respectively. Correlation coefficients for the calibration curves in the range 0.1-50 μg L(-1) were higher than 0.99 except for diazinon (0.1-25 μg L(-1)). Only 9 pesticides presented more than 20% of signal suppression/enhancement, no matrix effect was observed in the studied conditions for the rest of the target pesticides. The method developed was used to investigate the occurrence of pesticides in 59 water samples collected in paddy fields located in Spain and Uruguay. The study shows the presence of bensulfuron methyl, tricyclazole, carbendazim, imidacloprid, tebuconazole and quinclorac in a concentration range from 0.08 to 7.20 μg L(-1). Copyright © 2011 Elsevier B.V. All rights reserved.

  17. Quantum Games in ion traps

    International Nuclear Information System (INIS)

    Buluta, Iulia Maria; Fujiwara, Shingo; Hasegawa, Shuichi

    2006-01-01

    We propose a general, scalable framework for implementing two-choices-multiplayer Quantum Games in ion traps. In particular, we discuss two famous examples: the Quantum Prisoners' Dilemma and the Quantum Minority Game. An analysis of decoherence due to intensity fluctuations in the applied laser fields is also provided

  18. Quantum Games in ion traps

    Energy Technology Data Exchange (ETDEWEB)

    Buluta, Iulia Maria [Department of Quantum Engineering and Systems Science, University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-8656 (Japan)]. E-mail: noa@lyman.q.t.u-tokyo.ac.jp; Fujiwara, Shingo [Department of Quantum Engineering and Systems Science, University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-8656 (Japan)]. E-mail: fujiwara@lyman.q.t.u-tokyo.ac.jp; Hasegawa, Shuichi [Department of Quantum Engineering and Systems Science, University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-8656 (Japan)]. E-mail: hasegawa@q.t.u-tokyo.ac.jp

    2006-10-09

    We propose a general, scalable framework for implementing two-choices-multiplayer Quantum Games in ion traps. In particular, we discuss two famous examples: the Quantum Prisoners' Dilemma and the Quantum Minority Game. An analysis of decoherence due to intensity fluctuations in the applied laser fields is also provided.

  19. Ultrahigh-performance liquid chromatography-ion trap mass spectrometry characterization of the steroidal saponins of Dioscorea panthaica Prain et Burkill and its application for accelerating the isolation and structural elucidation of steroidal saponins.

    Science.gov (United States)

    Wang, Weihao; Zhao, Ye; Jing, Wenguang; Zhang, Jun; Xiao, Hui; Zha, Qin; Liu, An

    2015-03-01

    Dioscorea panthaica is a traditional Chinese medicinal herb used in the treatment of various physiological conditions, including cardiovascular disease, gastropathy and hypertension. Steroidal saponins (SS) are the main active ingredients of this herb and have effects on myocardial ischemia and cancer. The phytochemical evaluation of SS is both time-consuming and laborious, and the isolation and structural determination steps can be especially demanding. For this reason, the development of new methods to accelerate the processes involved in the identification, isolation and structural elucidation of SS is highly desirable. In this study, a new ultrahigh performance liquid chromatography-ion trap mass spectrometry (UHPLC-IT/MS(n)) method has been developed for the identification of the SS in D. panthaica Prain et Burkill. Notably, the current method can distinguish between spirostanol and furostanol-type compounds based on the fragmentation patterns observed by electrospray ionization-ion trap mass spectrometry (ESI-IT/MS(n)) analysis. UHPLC-IT/MS(n) was used to conduct a detailed investigation of the number, structural class and order of the sugar moieties in the sugar chains of the SS present in D. panthaica. The established fragmentation features were used to analyze the compounds found in the 65% ethanol fraction of the water extracts of D. panthaica. Twenty-three SS were identified, including 11 potential new compounds and six groups of isomers. Two of these newly identified SS were selected as representative examples, and their chemical structures were confirmed by (1)H and (13)C NMR analyses. This newly developed UHPLC-IT/MS(n) method therefore allowed for the efficient identification, isolation and structural determination of the SS in D. panthaica. Copyright © 2015 Elsevier Inc. All rights reserved.

  20. Scaling ion traps for quantum computing

    CSIR Research Space (South Africa)

    Uys, H

    2010-09-01

    Full Text Available The design, fabrication and preliminary testing of a chipscale, multi-zone, surface electrode ion trap is reported. The modular design and fabrication techniques used are anticipated to advance scalability of ion trap quantum computing architectures...

  1. Multiplex gas chromatography

    Science.gov (United States)

    Valentin, Jose R.

    1990-01-01

    The principles of the multiplex gas chromatography (GC) technique, which is a possible candidate for chemical analysis of planetary atmospheres, are discussed. Particular attention is given to the chemical modulators developed by present investigators for multiplex GC, namely, the thermal-desorption, thermal-decomposition, and catalytic modulators, as well as to mechanical modulators. The basic technique of multiplex GC using chemical modulators and a mechanical modulator is demonstrated. It is shown that, with the chemical modulators, only one gas stream consisting of the carrier in combination with the components is being analyzed, resulting in a simplified instrument that requires relatively few consumables. The mechanical modulator demonstrated a direct application of multiplex GC for the analysis of gases in atmosphere of Titan at very low pressures.

  2. Microscale ion trap mass spectrometer

    Science.gov (United States)

    Ramsey, J. Michael; Witten, William B.; Kornienko, Oleg

    2002-01-01

    An ion trap for mass spectrometric chemical analysis of ions is delineated. The ion trap includes a central electrode having an aperture; a pair of insulators, each having an aperture; a pair of end cap electrodes, each having an aperture; a first electronic signal source coupled to the central electrode; a second electronic signal source coupled to the end cap electrodes. The central electrode, insulators, and end cap electrodes are united in a sandwich construction where their respective apertures are coaxially aligned and symmetric about an axis to form a partially enclosed cavity having an effective radius r.sub.0 and an effective length 2z.sub.0, wherein r.sub.0 and/or z.sub.0 are less than 1.0 mm, and a ratio z.sub.0 /r.sub.0 is greater than 0.83.

  3. IDENTIFICATION OF MICROCYSTIN TOXINS FROM A STRAIN OF MICROCYSTIS AERUGINOSA BY LIQUID CHROMATOGRAPHY INTRODUCTION INTO A HYBRID LINEAR ION TRAP-FOURIER TRANSFORM ION CYCLOTRON RESONANCE MASS SPECTROMETER

    Science.gov (United States)

    The cyclic heptapeptide microcystin toxins produced by a strain of Microcystis aeruginosa that has not been investigated previously were separated by liquid chromatography and identified by high-accuracy m/z measurements of their [M + H]+ ions and the fragment i...

  4. Simultaneous Qualitation and Quantitation of Chlorogenic Acids in Kuding Tea Using Ultra-High-Performance Liquid Chromatography-Diode Array Detection Coupled with Linear Ion Trap-Orbitrap Mass Spectrometer.

    Science.gov (United States)

    Che, Yanyun; Wang, Zhibin; Zhu, Zhiyun; Ma, Yangyang; Zhang, Yaqiong; Gu, Wen; Zhang, Jiayu; Rao, Gaoxiong

    2016-12-16

    Kuding tea, the leaves of Ilex Kudingcha C.J. Tseng, has been applied for treating obesity, hypertension, cardiovascular disease, hyperlipidemia, and so on. The chlorogenic acids (CGAs) in Kuding tea have shown excellent antioxidative, antiobesity, anti-atherosclerotic and anticancer activities. Nevertheless, the chemical profiles of CGAs in Kuding tea have not been comprehensively studied yet, which hinders further quality control. In the present study, a sensitive ultra-high-performance liquid chromatography-diode array detection coupled with a linear ion trap-Orbitrap (UHPLC-DAD-LTQ-Orbitrap) method was established to screen and identify CGAs in Kuding tea. Six CGA standards were first analyzed in negative ion mode with a CID-MS/MS experiment and then the diagnostic product ions (DPIs) were summarized. According to the retention behavior in the RP-ODS column, accurate mass measurement, DPIs and relevant bibliography data, a total of 68 CGA candidates attributed to 12 categories were unambiguously or preliminarily screened and characterized within 18 min of chromatographic time. This was the first systematic report on the distribution of CGAs in Kuding tea. Meanwhile, the contents of 6 major CGAs in Kuding tea were also determined by the UHPLC-DAD method. All the results indicated that the established analytical method could be employed as an effective technique for the comprehensive and systematic characterization of CGAs and quality control of the botanic extracts or Chinese medicinal formulas that contain various CGAs.

  5. Chemometrics for comprehensive analysis of nucleobases, nucleosides, and nucleotides in Siraitiae Fructus by hydrophilic interaction ultra high performance liquid chromatography coupled with triple-quadrupole linear ion-trap tandem mass spectrometry.

    Science.gov (United States)

    Zhou, Guisheng; Wang, Mengyue; Xu, Renjie; Li, Xiao-Bo

    2015-10-01

    A rapid and sensitive hydrophilic interaction ultra high performance liquid chromatography coupled with triple-quadrupole linear ion-trap tandem mass spectrometry method was validated for the simultaneous determination of 20 nucleobases, nucleosides, and nucleotides (within 3.5 min), and then was employed to test the functional food of Luo-Han-Guo samples. The analysis showed that the Luo-Han-Guo was rich in guanosine and uridine, but contained trace levels of the other target compounds. Chemometrics methods were employed to identify 40 batches of Luo-Han-Guo samples from different cultivated forms, regions and varieties. Unsupervised hierarchical cluster analysis and principal component analysis were used to classify Luo-Han-Guo samples based on the level of the 20 target compounds, and the supervised learning method of counter propagation artificial neural network was utilized to further separate clusters and validate the established model. As a result, the samples could be clustered into three primary groups, in which correlation with cultivated varieties was observed. The present strategy could be applied to the investigation of other edible plants containing nucleobases, nucleosides, or nucleotides. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  6. Multiresidue analysis of 36 pesticides in soil using a modified quick, easy, cheap, effective, rugged, and safe method by liquid chromatography with tandem quadruple linear ion trap mass spectrometry.

    Science.gov (United States)

    Feng, Xue; He, Zeying; Wang, Lu; Peng, Yi; Luo, Ming; Liu, Xiaowei

    2015-09-01

    A new method for simultaneous determination of 36 pesticides, including 15 organophosphorus, six carbamate, and some other pesticides in soil was developed by liquid chromatography with tandem quadruple linear ion trap mass spectrometry. The extraction and clean-up steps were optimized based on the quick, easy, cheap, effective, rugged, and safe method. The data were acquired in multiple reaction monitoring mode combined with enhanced product ion to increase confidence of the analytical results. Validation experiments were performed in soil samples. The average recoveries of pesticides at four spiking levels (1, 5, 50, and 100 μg/kg) ranged from 63 to 126% with relative standard deviation below 20%. The limits of detection of pesticides were 0.04-0.8 μg/kg, and the limits of quantification were 0.1-2.6 μg/kg. The correlation coefficients (r(2) ) were higher than 0.990 in the linearity range of 0.5-200 μg/L for most of the pesticides. The method allowed for the analysis of the target pesticides in the lower μg/kg concentration range. The optimized method was then applied to the test of real soil samples obtained from several areas in China, confirming the feasibility of the method. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  7. Determination of sulfonamide antibiotics and metabolites in liver, muscle and kidney samples by pressurized liquid extraction or ultrasound-assisted extraction followed by liquid chromatography-quadrupole linear ion trap-tandem mass spectrometry (HPLC-QqLIT-MS/MS).

    Science.gov (United States)

    Hoff, Rodrigo Barcellos; Pizzolato, Tânia Mara; Peralba, Maria do Carmo Ruaro; Díaz-Cruz, M Silvia; Barceló, Damià

    2015-03-01

    Sulfonamides are widely used in human and veterinary medicine. The presence of sulfonamides residues in food is an issue of great concern. Throughout the present work, a method for the targeted analysis of 16 sulfonamides and metabolites residue in liver of several species has been developed and validated. Extraction and clean-up has been statistically optimized using central composite design experiments. Two extraction methods have been developed, validated and compared: i) pressurized liquid extraction, in which samples were defatted with hexane and subsequently extracted with acetonitrile and ii) ultrasound-assisted extraction with acetonitrile and further liquid-liquid extraction with hexane. Extracts have been analyzed by liquid chromatography-quadrupole linear ion trap-tandem mass spectrometry. Validation procedure has been based on the Commission Decision 2002/657/EC and included the assessment of parameters such as decision limit (CCα), detection capability (CCβ), sensitivity, selectivity, accuracy and precision. Method׳s performance has been satisfactory, with CCα values within the range of 111.2-161.4 µg kg(-1), limits of detection of 10 µg kg(-1) and accuracy values around 100% for all compounds. Copyright © 2014 Elsevier B.V. All rights reserved.

  8. Identification and determination of 34 water-soluble synthetic dyes in foodstuff by high performance liquid chromatography-diode array detection-ion trap time-of-flight tandem mass spectrometry.

    Science.gov (United States)

    Li, Xiu Qin; Zhang, Qing He; Ma, Kang; Li, Hong Mei; Guo, Zhen

    2015-09-01

    An accurate method combining high performance liquid chromatography (HPLC) with diode array detection (DAD) and ion-trap time-of-flight mass spectrometry (IT-TOF/MS) was developed for simultaneous identification and quantification of 34 water-soluble synthetic dyes in foodstuff. Fragmentation patterns of synthetic dyes were proposed based on IT-TOF/MS. The molecular ion [M+H](+) was not observed in the conventional single-stage mass spectra for most of synthetic dyes. The single-stage mass spectra of synthetic dyes all afforded the diagnostic ions [(M-nNa+nH)+H](+) or [(M-nNa+nH)-H](-) in the positive or negative mode. Doubly charged ions were the characteristic ions of azo dyes. An HPLC-DAD method was developed to analyze 34 synthetic dyes in foodstuffs. The limits of detection (LOD) for the dyes were 0.01-0.05 μg/mL. The recoveries were between 76.1% and 105.0% with a RSD ranging from 1.4% to 6.4%. This method was successfully applied to analyzing the 34 water-soluble synthetic dyes in 21 commercial foods. Copyright © 2015 Elsevier Ltd. All rights reserved.

  9. Metabolism studies of the Kratom alkaloids mitraciliatine and isopaynantheine, diastereomers of the main alkaloids mitragynine and paynantheine, in rat and human urine using liquid chromatography-linear ion trap-mass spectrometry.

    Science.gov (United States)

    Philipp, Anika A; Wissenbach, Dirk K; Weber, Armin A; Zapp, Josef; Maurer, Hans H

    2011-05-01

    Mitragyna speciosa (Kratom in Thai), native in Southeast Asia, is increasingly misused as a herbal drug of abuse. During metabolism studies on the Kratom alkaloids mitragynine, its diastereomers speciogynine and speciociliatine as well as paynantheine in rats and humans, further isomeric compounds were detected in Kratom users' urine. The question arose whether these compounds were formed from the low abundant, isomeric alkaloids mitraciliatine (MC) and isopaynantheine (ISO-PAY). Therefore, the aim of the presented study was to identify using liquid chromatography-linear ion trap-mass spectrometry their phase I and II metabolites in rat urine after administration of pure MC or ISO-PAY, to confirm their formation in humans, and finally to confirm whether the above-mentioned isomeric compounds in human urine represent MC and ISO-PAY and/or their metabolites. The metabolic pathways of both alkaloids in rats were found to be comparable to those of their corresponding diastereomers. In the human urines tested, not all metabolites found in rats could be detected because of the much lower amounts of MC and ISO-PAY in Kratom. However, all the above-mentioned so far unknown isomeric compounds could be identified in the human urine samples as MC, ISO-PAY and/or their metabolites. The used LC separation was also suitable for the differentiation of all other Kratom alkaloids and their metabolites in human urine. Copyright © 2011 Elsevier B.V. All rights reserved.

  10. Lithium adduct as precursor ion for sensitive and rapid quantification of 20 (S)-protopanaxadiol in rat plasma by liquid chromatography/quadrupole linear ion trap mass spectrometry and application to rat pharmacokinetic study.

    Science.gov (United States)

    Bao, Yuanwu; Wang, Quanying; Tang, Pingming

    2013-03-01

    A novel, rapid and sensitive liquid chromatography/quadrupole linear ion trap mass spectrometry [LC-ESI-(QqLIT)MS/MS] method was developed and validated for the quantification of protopanaxadiol (PPD) in rat plasma. Oleanolic acid (OA) was used as internal standard (IS). A simple protein precipitation based on acetonitrile (ACN) was employed. Chromatographic separation was performed on a Sepax GP-C18 column (50 × 2.1 mm, 5 μM) with a mobile phase consisting of ACN-water and 1.5 μM formic acid and 25 mM lithium acetate (90 : 10, v/v) at a flow rate of 0.4 ml/min for 3.0 min. Multiple-reaction-monitoring mode was performed using lithium adduct ion as precursor ion of m/z 467.5/449.4 and 455.6/407.4 for the drug and IS, respectively. Calibration curve was recovered over a concentration range of 0.5-100 ng/ml with a correlation coefficient >0.99. The limit of detection was 0.2 ng/ml in rat plasma for PPD. The results of the intraday and interday precision and accuracy studies were well within the acceptable limits. The validated method was successfully applied to investigate the pharmacokinetic study of PPD after intravenous and gavage administration to rat. Copyright © 2013 John Wiley & Sons, Ltd.

  11. Simultaneous Qualitative and Quantitative Analysis of Multiple Chemical Constituents in YiQiFuMai Injection by Ultra-Fast Liquid Chromatography Coupled with Ion Trap Time-of-Flight Mass Spectrometry

    Directory of Open Access Journals (Sweden)

    Chunhua Liu

    2016-05-01

    Full Text Available YiQiFuMai injection (YQFM is a modern lyophilized powder preparation derived from the traditional Chinese medicine Sheng-mai san (SMS used for treating cardiovascular diseases, such as chronic heart failure. However, its chemical composition has not been fully elucidated, particularly for the preparation derived from Ophiopogon japonicus. This study aimed to establish a systematic and reliable method to quickly and simultaneously analyze the chemical constituents in YQFM by ultra-fast liquid chromatography coupled with ion trap time-of-flight mass spectrometry (UFLC-IT-TOF/MS. Sixty-five compounds in YQFM were tentatively identified by comparison with reference substances or literature data. Furthermore, twenty-one compounds, including three ophiopogonins, fifteen ginsenosides and three lignans were quantified by UFLC-IT-TOF/MS. Notably, this is the first determination of steroidal saponins from O. japonicus in YQFM. The relative standard deviations (RSDs of intra- and inter-day precision, reproducibility and stability were <4.9% and all analytes showed good linearity (R2 ≥ 0.9952 and acceptable recovery of 91.8%–104.2% (RSD ≤ 5.4%, indicating that the methods were reliable. These methods were successfully applied to quantitative analysis of ten batches of YQFM. The developed approach can provide useful and comprehensive information for quality control, further mechanistic studies in vivo and clinical application of YQFM.

  12. Detection of previously unknown fumonisin P analogue mycotoxins in a Fusarium verticillioides culture by high-performance liquid chromatography-electrospray ionization time-of-flight and ion trap mass spectrometry.

    Science.gov (United States)

    Bartók, Tibor; Tölgyesi, László; Szécsi, Árpád; Mesterházy, Ákos; Bartók, Mihály; Gyimes, Ernő; Véha, Antal

    2014-07-01

    Five previously unknown fumonisin mycotoxins (iso-FP1, iso-FP(2,3a), iso-FP(2,3b), FP4 and iso-FP4) and three previously described FP analogues (FP(1-3)) were detected in a solid rice culture inoculated with Fusarium verticillioides. The fumonisins were characterized by high-performance liquid chromatography-electrospray ionization time-of-flight mass spectrometry (HPLC-ESI-TOFMS) and ion trap mass spectrometry (ITMS). The FP isomers were separated by using a flat gradient on a special, high-coverage C18, narrow-bore HPLC column (YMC-Pack J'sphere ODS H80), which was suggested for the separation of structural isomers. The verified structures of the FP(1-3) mycotoxins, the relative retention times (by HPLC-ESI-TOFMS and ITMS), the exact masses of the molecular ions (by TOFMS) and the masses of the product ions, including the hydrocarbon backbones (by ITMS) of the new compounds, strongly suggested their structures. © The Author [2013]. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  13. Rapid analysis of multiclass antibiotic residues and some of their metabolites in hospital, urban wastewater and river water by ultra-high-performance liquid chromatography coupled to quadrupole-linear ion trap tandem mass spectrometry.

    Science.gov (United States)

    Gros, Meritxell; Rodríguez-Mozaz, Sara; Barceló, Damià

    2013-05-31

    The present work describes the development of a fast and robust analytical method for the determination of 53 antibiotic residues, covering various chemical groups and some of their metabolites, in environmental matrices that are considered important sources of antibiotic pollution, namely hospital and urban wastewaters, as well as in river waters. The method is based on automated off-line solid phase extraction (SPE) followed by ultra-high-performance liquid chromatography coupled to quadrupole linear ion trap tandem mass spectrometry (UHPLC-QqLIT). For unequivocal identification and confirmation, and in order to fulfill EU guidelines, two selected reaction monitoring (SRM) transitions per compound are monitored (the most intense one is used for quantification and the second one for confirmation). Quantification of target antibiotics is performed by the internal standard approach, using one isotopically labeled compound for each chemical group, in order to correct matrix effects. The main advantages of the method are automation and speed-up of sample preparation, by the reduction of extraction volumes for all matrices, the fast separation of a wide spectrum of antibiotics by using ultra-high-performance liquid chromatography, its sensitivity (limits of detection in the low ng/L range) and selectivity (due to the use of tandem mass spectrometry) The inclusion of β-lactam antibiotics (penicillins and cephalosporins), which are compounds difficult to analyze in multi-residue methods due to their instability in water matrices, and some antibiotics metabolites are other important benefits of the method developed. As part of the validation procedure, the method developed was applied to the analysis of antibiotics residues in hospital, urban influent and effluent wastewaters as well as in river water samples. Copyright © 2013 Elsevier B.V. All rights reserved.

  14. Determination of interglycosidic linkages in O-glycosyl flavones by high-performance liquid chromatography/photodiode-array detection coupled to electrospray ionization ion trap mass spectrometry. Its application to Tetragonula carbonaria honey from Australia.

    Science.gov (United States)

    Truchado, Pilar; Vit, Patricia; Heard, Tim A; Tomás-Barberán, Francisco A; Ferreres, Federico

    2015-05-30

    Tetragonula carbonaria pot-honeys are highly valued as a food source and for their biological activities in Australia, and there is a growing interest to know its composition. Phenolic metabolites, which could be related to their beneficial properties, have not been studied in depth yet. Mass spectrometry (MS) coupled to liquid chromatography (LC) is an advanced technique for the study of complex flavonoids present in difficult food matrices that hampers their isolation and purification. This allows the tentative characterization of diglycosides/triglycosides establishing the position of the O-glycosylation on the sugar moiety by the study of the MS data in T. carbonaria pot-honeys from Australia. Their spectra obtained by high-performance liquid chromatography/photodiode-array detection/electrospray ionization ion trap mass spectrometry (HPLC/DAD/ESI-MS(n) ) revealed for the first time 19 quercetin, kaempferol and isorhamnetin O-glycosides. These compounds were clustered in flavonoid triglycosides, diglycosides and monoglycosides. The first cluster contained one flavonoid trihexoside, two -3-O-(2-hexosyl, 6-rhamnosyl)hexosides and their isomers and two -3-O-(2,6-di-rhamnosyl)hexosides. In the second cluster, eleven flavonoid diglycosides such as three -3-O-(2-hexosyl)hexosides, four -3-O-(2-rhamnosyl)hexosides and one -3-O-(6-rhamnosyl)hexoside as well as two -3-O-(2-pentosyl)hexosides and one tentative -3-O-(3-pentosyl)hexoside were detected. In the monoglycoside group, only one flavonoid -3-O-hexoside was identified. The occurrence of this large number of flavonoid glycosides could be due to the low glucosidase activity previously reported in stingless bee honey. Copyright © 2015 John Wiley & Sons, Ltd.

  15. Localization of double bonds in triacylglycerols using high-performance liquid chromatography/atmospheric pressure chemical ionization ion-trap mass spectrometry

    Czech Academy of Sciences Publication Activity Database

    Háková, Eva; Vrkoslav, Vladimír; Míková, Radka; Schwarzová-Pecková, K.; Bosáková, Z.; Cvačka, Josef

    2015-01-01

    Roč. 407, č. 17 (2015), s. 5175-5188 ISSN 1618-2642 R&D Projects: GA ČR GAP206/12/0750 Institutional support: RVO:61388963 Keywords : double bond * gas-phase chemistry * lipidomics * olive oil * vernix caseosa Subject RIV: CB - Analytical Chemistry, Separation Impact factor: 3.125, year: 2015

  16. Microfabricated linear Paul-Straubel ion trap

    Science.gov (United States)

    Mangan, Michael A [Albuquerque, NM; Blain, Matthew G [Albuquerque, NM; Tigges, Chris P [Albuquerque, NM; Linker, Kevin L [Albuquerque, NM

    2011-04-19

    An array of microfabricated linear Paul-Straubel ion traps can be used for mass spectrometric applications. Each ion trap comprises two parallel inner RF electrodes and two parallel outer DC control electrodes symmetric about a central trap axis and suspended over an opening in a substrate. Neighboring ion traps in the array can share a common outer DC control electrode. The ions confined transversely by an RF quadrupole electric field potential well on the ion trap axis. The array can trap a wide array of ions.

  17. Gas chromatography: mass selective detector

    International Nuclear Information System (INIS)

    Lapinskas, R.

    1988-01-01

    The mechanism of mass spectrometry technique directed for detecting molecular structures is described, with some considerations about its operational features. This mass spectrometer is used as a gas chromatography detector. (author)

  18. Gas chromatographic determination of pesticides in vegetable samples by sequential positive and negative chemical ionization and tandem mass spectrometric fragmentation using an ion trap analyser.

    Science.gov (United States)

    Hernando, M D; Agüera, A; Fernández-Alba, A R; Piedra, L; Contreras, M

    2001-01-01

    A selective and sensitive chromatographic method is described for the determination of nine organochlorine and organophosphorus pesticides in vegetable samples by gas chromatography-mass spectrometry. The proposed method combines the use of positive and negative chemical ionisation and tandem mass spectrometric fragmentation, resulting in a significant increase in selectivity and allowing the simultaneous confirmation and quantification of trace levels of pesticides in complex vegetable matrices. Parameters relative to ionisation and fragmentation processes were optimised to obtain maximum sensitivity. Repeatability and reproducibility studies yielded relative standard deviations lower than 25% in all cases. Identification criteria, such as retention time and relative abundance of characteristic product ions, were also evaluated in order to guarantee the correct identification of the target compounds. The method was applied to real vegetable samples to demonstrate its use in routine analysis.

  19. Use of liquid chromatography coupled to low- and high-resolution linear ion trap mass spectrometry for studying the metabolism of paynantheine, an alkaloid of the herbal drug Kratom in rat and human urine.

    Science.gov (United States)

    Philipp, Anika A; Wissenbach, Dirk K; Weber, Armin A; Zapp, Josef; Zoerntlein, Siegfried W; Kanogsunthornrat, Jidapha; Maurer, Hans H

    2010-04-01

    The Thai medicinal plant Mitragyna speciosa (Kratom in Thai) is misused as a herbal drug of abuse. During studies on the main Kratom alkaloid mitragynine (MG) in rats and humans, several dehydro analogs could be detected in urine of Kratom users, which were not found in rat urine after administration of pure MG. Questions arose as to whether these compounds are formed from MG only by humans or whether they are metabolites formed from the second abundant Kratom alkaloid paynantheine (PAY), the dehydro analog of MG. Therefore, the aim of the presented study was to identify the phase I and II metabolites of PAY in rat urine after administration of the pure alkaloid. This was first isolated from Kratom leaves. Liquid chromatography-linear ion trap mass spectrometry provided detailed structure information of the metabolites in the MS(n) mode particularly with high resolution. Besides PAY, the following phase I metabolites could be identified: 9-O-demethyl PAY, 16-carboxy PAY, 9-O-demethyl-16-carboxy PAY, 17-O-demethyl PAY, 17-O-demethyl-16,17-dihydro PAY, 9,17-O-bisdemethyl PAY, 9,17-O-bisdemethyl-16,17-dihydro PAY, 17-carboxy-16,17-dihydro PAY, and 9-O-demethyl-17-carboxy-16,17-dihydro PAY. These metabolites indicated that PAY was metabolized via the same pathways as MG. Several metabolites were excreted as glucuronides or sulfates. The metabolism studies in rats showed that PAY and its metabolites corresponded to the MG-related dehydro compounds detected in urine of the Kratom users. In conclusion, PAY and its metabolites may be further markers for a Kratom abuse in addition of MG and its metabolites.

  20. Application of a hybrid ordered mesoporous silica as sorbent for solid-phase multi-residue extraction of veterinary drugs in meat by ultra-high-performance liquid chromatography coupled to ion-trap tandem mass spectrometry.

    Science.gov (United States)

    Casado, Natalia; Morante-Zarcero, Sonia; Pérez-Quintanilla, Damián; Sierra, Isabel

    2016-08-12

    A quick, sensitive and selective analytical reversed-phase multi-residue method using ultra-high performance liquid chromatography coupled to an ion-trap mass spectrometry detector (UHPLC-IT-MS/MS) operating in both positive and negative ion mode was developed for the simultaneous determination of 23 veterinary drug residues (β-blockers, β-agonists and Non-Steroidal Anti-inflammatory Drugs (NSAIDs)) in meat samples. The sample treatment involved a liquid-solid extraction followed by a solid-phase extraction (SPE) procedure. SBA-15 type mesoporous silica was synthetized and modified with octadecylsilane, and the resulting hybrid material (denoted as SBA-15-C18) was applied and evaluated as SPE sorbent in the purification of samples. The materials were comprehensively characterized, and they showed a high surface area, high pore volume and a homogeneous distribution of the pores. Chromatographic conditions and extraction procedure were optimized, and the method was validated according to the Commission Decision 2002/657/EC. The method detection limits (MDLs) and the method quantification limits (MQLs) were determined for all the analytes in meat samples and found to range between 0.01-18.75μg/kg and 0.02-62.50μg/kg, respectively. Recoveries for 15 of the target analytes ranged from 71 to 98%. In addition, for comparative purpose SBA-15-C18 was evaluated towards commercial C18 amorphous silica. Results revealed that SBA-15-C18 was clearly more successful in the multi-residue extraction of the 23 mentioned analytes with higher recovery values. The method was successfully tested to analyze prepacked preparations of mince bovine meat. Traces of propranolol, ketoprofen and diclofenac were detected in some samples. Copyright © 2016 Elsevier B.V. All rights reserved.

  1. A strategy for comprehensive identification of sequential constituents using ultra-high-performance liquid chromatography coupled with linear ion trap-Orbitrap mass spectrometer, application study on chlorogenic acids in Flos Lonicerae Japonicae.

    Science.gov (United States)

    Zhang, Jia-yu; Wang, Zi-jian; Li, Yun; Liu, Ying; Cai, Wei; Li, Chen; Lu, Jian-qiu; Qiao, Yan-jiang

    2016-01-15

    The analytical methodologies for evaluation of multi-component system in traditional Chinese medicines (TCMs) have been inadequate or unacceptable. As a result, the unclarity of multi-component hinders the sufficient interpretation of their bioactivities. In this paper, an ultra-high-performance liquid chromatography coupled with linear ion trap-Orbitrap (UPLC-LTQ-Orbitrap)-based strategy focused on the comprehensive identification of TCM sequential constituents was developed. The strategy was characterized by molecular design, multiple ion monitoring (MIM), targeted database hits and mass spectral trees similarity filter (MTSF), and even more isomerism discrimination. It was successfully applied in the HRMS data-acquisition and processing of chlorogenic acids (CGAs) in Flos Lonicerae Japonicae (FLJ), and a total of 115 chromatographic peaks attributed to 18 categories were characterized, allowing a comprehensive revelation of CGAs in FLJ for the first time. This demonstrated that MIM based on molecular design could improve the efficiency to trigger MS/MS fragmentation reactions. Targeted database hits and MTSF searching greatly facilitated the processing of extremely large information data. Besides, the introduction of diagnostic product ions (DPIs) discrimination, ClogP analysis, and molecular simulation, raised the efficiency and accuracy to characterize sequential constituents especially position and geometric isomers. In conclusion, the results expanded our understanding on CGAs in FLJ, and the strategy could be exemplary for future research on the comprehensive identification of sequential constituents in TCMs. Meanwhile, it may propose a novel idea for analyzing sequential constituents, and is promising for quality control and evaluation of TCMs. Copyright © 2015 Elsevier B.V. All rights reserved.

  2. Simultaneous determination of 19 triazine pesticides and degradation products in processed cereal samples from Chinese total diet study by isotope dilution-high performance liquid chromatography-linear ion trap mass spectrometry.

    Science.gov (United States)

    Li, Peng; Yang, Xin; Miao, Hong; Zhao, Yunfeng; Liu, Wei; Wu, Yongning

    2013-06-05

    A selective and sensitive isotope dilution-high performance liquid chromatography-linear ion trap mass spectrometry (Isotope Dilution-HPLC-LIT-MS(3)) method was developed for the simultaneous determination of 19 triazine pesticides and their degradation products in processed cereal samples from Chinese total diet study (TDS). The method integrated the addition of isotope internal standards, liquid-liquid extraction (LLE), clean-up with MCX solid-phase extraction (SPE) cartridges and HPLC-LIT-MS(3) analysis with selected reaction monitoring (SRM) mode. Matrix-matched calibration curves showed good linearity (R(2)≥0.9940) verified by applying the Mandel's fitting test (p>0.087) performed at the 95% confidence level. Decision limits (CCαs) and detection capabilities (CCβs) of the 19 triazine pesticides and their degradation products fell in the ranges of 0.0020-0.4200 μg kg(-1) and 0.0024-0.4500 μg kg(-1), respectively. Recoveries ranged from 70.1% to 112.8%, with the relative standard deviations (RSDs) ranging from 1.5% to 13.5%. Furthermore, the proposed method was applied to analyzing the proposed cereal samples from the fourth Chinese TDS. Eleven triazines were detected in six cereal samples with the concentrations ranging from 0.013 to 0.987 μg kg(-1). This method can also be used for the further determination of the triazines in other food group composites, and ultimately served as a methodological foundation for assessing the triazines in the average Chinese diet in the general population. Copyright © 2013 Elsevier B.V. All rights reserved.

  3. Approach to the study of flavone di-C-glycosides by high performance liquid chromatography-tandem ion trap mass spectrometry and its application to characterization of flavonoid composition in Viola yedoensis.

    Science.gov (United States)

    Cao, Jie; Yin, Chengle; Qin, Yan; Cheng, Zhihong; Chen, Daofeng

    2014-10-01

    The mass spectrometric (MS) analysis of flavone di-C-glycosides has been a difficult task due to pure standards being unavailable commercially and to that the reported relative intensities of some diagnostic ions varied with MS instruments. In this study, five flavone di-C-glycoside standards from Viola yedoensis have been systematically studied by high performance liquid chromatography-electrospray ionization-tandem ion trap mass spectrometry (HPLC-ESI-IT-MS(n)) in the negative ion mode to analyze their fragmentation patterns. A new MS(2) and MS(3) hierarchical fragmentation for the identification of the sugar nature (hexoses or pentoses) at C-6 and C-8 is presented based on previously established rules of fragmentation. Here, for the first time, we report that the MS(2) and MS(3) structure-diagnostic fragments about the glycosylation types and positions are highly dependent on the configuration of the sugars at C-6 and C-8. The base peak ((0,2) X1 (0,2) X(2)(-) ion) in MS(3) spectra of di-C-glycosides could be used as a diagnostic ion for flavone aglycones. These newly proposed fragmentation behaviors have been successfully applied to the characterization of flavone di-C-glycosides found in V. yedoensis. A total of 35 flavonoid glycosides, including 1 flavone mono-C-hexoside, 2 flavone 6,8-di-C-hexosides, 11 flavone 6,8-di-C-pentosides, 13 flavone 6,8-C-hexosyl-C-pentosides, 5 acetylated flavone C-glycosides and 3 flavonol O-glycosides, were identified or tentatively identified on the base of their UV profiles, MS and MS(n) (n = 5) data, or by comparing with reference substances. Among these, the acetylated flavone C-glycosides were reported from V. yedoensis for the first time. Copyright © 2014 John Wiley & Sons, Ltd.

  4. Identification of unsaturated N-acylhomoserine lactones in bacterial isolates of Rhodobacter sphaeroides by liquid chromatography coupled to electrospray ionization-hybrid linear ion trap-Fourier transform ion cyclotron resonance mass spectrometry.

    Science.gov (United States)

    Cataldi, Tommaso R I; Bianco, Giuliana; Abate, Salvatore; Losito, Ilario

    2011-07-15

    The identification of two unsaturated N-acylhomoserine lactones (AHLs) produced by Rhodobacter sphaeroides bacteria, based on liquid chromatography (LC) coupled to a hybrid quadrupole linear ion trap (LTQ)-Fourier transform ion cyclotron resonance (FTICR) mass spectrometer upon electrospray ionization (ESI), is presented. Besides the confirmation of the signaling molecule already described in the literature, i.e. (Z)-N-tetradec-7-enoyl-homoserine lactone (C(14:1)-HSL), we have discovered the occurrence, at low, yet significant levels, of another monounsaturated compound, C(12:1) -HSL, which may extend the number of small diffusible chemical signals known for R. sphaeroides. Both unsaturated AHLs were identified by high-resolution FTICR mass spectrometry in extracts of bacterial culture media and the occurrence of a C=C bond was assessed upon their conversion into bromohydrins. Collision-induced dissociation (CID) spectra were then collected on the LTQ mass analyzer. A careful comparison of tandem MS spectra of monounsaturated (i.e., C(12:1)-HSL and C(14:1)-HSL) and saturated AHLs (i.e. C(12)-HSL and C(14)-HSL) led to the emphasis of two series of product ions, exhibiting 14 Da spaced m/z ratios. Both series were referred to progressive fragmentations at the aliphatic end of the AHL acyl chains, followed by neutral losses of terminal alkenes (i.e. CH(2)=CH(CH(2))(n)H). In particular, the series located at the higher end of the explored m/z range (>200 Da), observed only for monounsaturated species, enabled the location of the C=C bond between carbons 7 and 8 of the acyl chain. Copyright © 2011 John Wiley & Sons, Ltd.

  5. First determination of C 60 and C 70 fullerenes and N-methylfulleropyrrolidine C 60 on the suspended material of wastewater effluents by liquid chromatography hybrid quadrupole linear ion trap tandem mass spectrometry

    Science.gov (United States)

    Farré, Marinella; Pérez, Sandra; Gajda-Schrantz, Krisztina; Osorio, Victoria; Kantiani, Lina; Ginebreda, Antoni; Barceló, Damià

    2010-03-01

    SummaryThe increasing use and production of carbon-based nanoparticles demands for new analytical approaches able to achieve sensitivities in the low ng/L range in order to assess their presence in environmental samples. This paper describes development, optimization and validation of a novel method for the analysis of C 60 and, C 70 fullerenes and N-methylfulleropyrrolidine C 60 in the environment. The method relies on ultrasonication extraction from suspended solids in wastewater, followed by liquid chromatography (LC) coupled to a hybrid triple quadrupole linear ion trap mass spectrometry (QqLIT-MS) for trace quantification. Recoveries obtained were generally higher than 60% for both surface water and wastewaters. The overall variability of the method was below 15%, for the three fullerenes and all tested matrices: ultra-pure water, surface water and wastewater. For the effluents of wastewater treatment plants the method quantification limits (MQL) ranged from 0.2 to 1 ng/L. The precision of the method, calculated as relative standard deviation (RSD), ranged from 1% to 2% and from 5% to 9% for intra and inter-day analysis, respectively. The developed analytical method was applied to the analysis of fullerenes in the effluents of 22 wastewater treatment plants in Catalonia (NE of Spain). 50% of the analyzed samples contained fullerenes, nine of them in the μg/L concentration range. This work constitutes the first report on the occurrence of fullerenes in suspended solids of wastewater effluents highlighting the need of nanotechnologies residues assessment for risk evaluation of nanoparticles in the environment.

  6. On-Line Derivatization Gas Chromatography Ion Trap Mass Spectrometry for Determination of Endocrine Disruptors in Surface Water

    Energy Technology Data Exchange (ETDEWEB)

    Tzing, Shin-Hwa; Chang, Jia-Yaw; Ling, Yong-Chien

    2004-03-31

    A method has been developed for the determination of endocrine disruptors (EDs) (containing hydroxyl groups) in surface water from different sources. The surface water samples from different sites including school and local dormitory sewage effluents, lake water and river water were collected and analyzed. In this method, the pretreated sample is directly analyzed by GC-MS using on-line derivatization, where tetramethylammonium hydroxide (TMA-OH) was used as the derivatizing agent. Use of large-volume direct sample introduction (DSI) and co-injection of the sample and TMAOH avoids external contaminations as observed in conventional derivatization protocols. Additionally, the use of chemical ionization (CI) and CI-MS/MS could enable detection of EDs at lower concentrations and reduce the matrices' interference thereby enhancing detection sensitivity of EDs for quantification. In this work, the use of dichloromethane as CI reagent for EDs is reported for the first time and could detect EDs to concentrations as low as 0.5 pg/mL. The recovery ranged from 74 to 112 % and the relative standard derivations for replicate analyses ranged from 5 to 17 %. We hope that this method will be applicable for routine analysis of EDs with hydroxyl functional groups.

  7. Application of a trap-free two-dimensional liquid chromatography combined with ion trap/time-of-flight mass spectrometry for separation and characterization of impurities and isomers in cefpiramide.

    Science.gov (United States)

    Wang, Jian; Xu, Yu; Wen, Chunmei; Wang, Zhijian

    2017-11-01

    High-resolution mass spectrometry had been routinely used for structure identification of impurity. However, all LC-MS methods were based on a volatile mobile phase, and a non-volatile system is used in the official analytical method of United States Pharmacopoeia for cefpiramide which limited the use of mass spectrometry for structure characterization of the impurities. Here we presented the utilization of a trap-free two-dimensional liquid chromatography coupled to high resolution ion trap/time-of-flight mass spectrometry (2D LC-IT-TOF MS) with positive and negative modes of electrospray ionization for characterization of eight impurities in cefpiramide. Trap-free two-dimensional liquid chromatography and online desalting technique made it possible to characterize the impurity in cefpiramide in the condition of official standard, and the TIC chromatogram of LC-MS was in conformity with the LC chromatogram of the official analytical method in the peak sequence of impurities, which could further improve the method of official monographs in pharmacopoeias. Each peak separated by the non-volatile mobile phase was trapped by a 20 μL quantitative loop then transferred into a system with a volatile mobile phase connected to a MS detector. In the first dimension, the column was Kromasil C 8 analytical column (250 mm × 4.6 mm, 5 μm) with a non-volatile salt mobile phase at the flow rate of 0.8 mL min -1 . In the second dimension, the column was Shimadzu Shim-pack GISS C 18 (50 mm × 2.1 mm, 1.9 μm) with a volatile salt mobile phase at the flow rate of 0.3 mL min -1 . Through the multiple heart-cutting 2D-LC approach and online desalting technique, the problem of incompatibility between non-volatile salt mobile phase and mass spectrometry was solved completely. The fragmentation behavior of cefpiramide and its eight impurities were studied. The structures of eight impurities in cefpiramide drug substance were deduced based on the HPLC-MS n data, in

  8. Methanol Chemical Ionization Ion Trap Mass Spectrometry of VX Degradation Products

    National Research Council Canada - National Science Library

    Rohrbaugh, Dennis

    1999-01-01

    ... for on-site analysis by being easier to transport and safer to use than gas cylinders: Ion trap EI and methanol CI mass spectra are provided as a reference for future identification of these compounds.

  9. Analysis of S-adenosylmethionine and related sulfur metabolites in bacterial isolates of Pseudomonas aeruginosa (BAA-47) by liquid chromatography/electrospray ionization coupled to a hybrid linear quadrupole ion trap and Fourier transform ion cyclotron resonance mass spectrometry.

    Science.gov (United States)

    Cataldi, Tommaso R I; Bianco, Giuliana; Abate, Salvatore; Mattia, Daniela

    2009-11-01

    A comprehensive and highly selective method for detecting in bacterial supernatants a modified sulfur nucleoside, S-adenosyl-L-methionine (SAM), and its metabolites, i.e., S-adenosylhomocysteine (SAH), adenosine (Ado), 5'-deoxy-5'-methylthioadenosine (MTA), adenine (Ade), S-adenosyl-methioninamine (dcSAM), homocysteine (Hcy) and methionine (Met), was developed. The method is based on reversed-phase liquid chromatography with positive electrospray ionization (ESI+) coupled to a hybrid linear quadrupole ion trap (LTQ) and 7-T Fourier transform ion cyclotron resonance mass spectrometry (FTICRMS). A gradient elution was employed with a binary solvent of 0.05 M ammonium formate at pH 4 and acetonitrile. The assay involves a simultaneous cleanup of cell-free bacterial broths by solid-phase extraction and trace enrichment of metabolites with a 50-fold concentration factor by using immobilized phenylboronic and anion-exchange cartridges. While the quantitative determination of SAM was performed using stable-isotope-labeled SAM-d3 as an internal standard, in the case of Met and Ade, Met-13C and Ade-15N2 were employed as isotope-labeled internal standards, respectively. This method enabled the identification of SAM and its metabolites in cell-free culture of Pseudomonas aeruginosa grown in Davis minimal broth (formulation without sulphur organic compounds), with routine sub-ppm mass accuracies (-0.27 +/- 0.68 ppm). The resulting contents of S(C)S(S)-SAM, S(S)-dcSAM, MTA, Ado and Met in the free-cell supernatant of P. aeruginosa was 56.4 +/- 2.1 nM, 32.2 +/- 2.2 nM, 0.91 +/- 0.10 nM, 19.6 +/- 1.2 nM and 1.93 +/- 0.02 microM (mean +/- SD, n = 4 extractions), respectively. We report also the baseline separation (Rs > or = 1.5) of both diastereoisomeric forms of SAM (S(C)S(S) and S(C)R(S)) and dcSAM (S(S) and R(S)), which can be very useful to establish the relationship between the biologically active versus the inactive species, S(C)S(S)/S(C)R(S) and S(S)/R(S) of SAM and dc

  10. Application of liquid chromatography/electrospray ionization ion trap tandem mass spectrometry for the evaluation of global nucleic acids: methylation in garden cress under exposure to CuO nanoparticles.

    Science.gov (United States)

    Alcazar Magana, Armando; Wrobel, Kazimierz; Corrales Escobosa, Alma Rosa; Wrobel, Katarzyna

    2016-01-15

    A full understanding of the biological impact of nanomaterials demands analytical procedures suitable for the detection/quantification of epigenetic changes that occur in the exposed organisms. Here, the effect of CuO nanoparticles (NPs) on global methylation of nucleic acids in Lepidium sativum was evaluated by liquid chromatography/ion trap mass spectrometry. Enhanced selectivity toward cytosine-containing nucleosides was achieved by using their proton-bound dimers formed in positive electrospray ionization (ESI(+)) as precursor ions for multiple reaction monitoring (MRM) quantification based on one or two ion transitions. Plants were exposed to CuO NPs (0-1000 mg L(-1)); nucleic acid extracts were washed with bathocuproine disulfate; nucleosides were separated on a Luna C18 column coupled via ESI(+) to an AmaZon SL mass spectrometer (Bruker Daltonics). Cytidine, 2´-deoxycytidine, 5-methylcytidine, 5-methyl-2´-deoxycytidine and 5-hydroxymethyl-2´-deoxycytidine were quantified by MRM based on MS(3) ([2M+H](+)/[M+H](+)/[M+H-132](+) or [M+H-116](+)) and MS(2) ([2M+H](+)/[M+H](+) ). Bathocuproine disulfate, added as Cu(I) complexing agent, allowed for elimination of [2M+Cu](+) adducts from the mass spectra. Poorer instrumental detection limits were obtained for MS(3) (20-120 fmol) as compared to MS(2) (9.0-41 fmol); however, two ion transitions helped to eliminate matrix effects in plant extracts. The procedure was tested by analyzing salmon sperm DNA (Sigma) and applied for the evaluation of DNA and RNA methylation in plants; in the absence of NPs, 13.03% and 0.92% methylated cytosines were found in DNA and RNA, respectively; for NPs concentration >50 mg L(-1), DNA hypomethylation was observed with respect to unexposed plants. RNA methylation did not present significant changes upon plant exposure; 5-hydroxymethyl-2´-deoxycytidine was not detected in any sample. The MRM quantification proposed here of cytosine-containing nucleosides using their proton-bound homo

  11. A comprehensive library-based, automated screening procedure for 46 synthetic cannabinoids in serum employing liquid chromatography-quadrupole ion trap mass spectrometry with high-temperature electrospray ionization.

    Science.gov (United States)

    Huppertz, Laura M; Kneisel, Stefan; Auwärter, Volker; Kempf, Jürgen

    2014-02-01

    Considering the vast variety of synthetic cannabinoids and herbal mixtures - commonly known as 'Spice' or 'K2' - on the market and the resulting increase of severe intoxications related to their consumption, there is a need in clinical and forensic toxicology for comprehensive up-to-date screening methods. The focus of this project aimed at developing and implementing an automated screening procedure for the detection of synthetic cannabinoids in serum using a liquid chromatography-ion trap-MS (LC-MS(n)) system and a spectra library-based approach, currently including 46 synthetic cannabinoids and 8 isotope labelled analogues. In the process of method development, a high-temperature ESI source (IonBooster(TM), Bruker Daltonik) and its effects on the ionization efficiency of the investigated synthetic cannabinoids were evaluated and compared to a conventional ESI source. Despite their structural diversity, all investigated synthetic cannabinoids benefitted from high-temperature ionization by showing remarkably higher MS intensities compared to conventional ESI. The employed search algorithm matches retention time, MS and MS(2)/MS(3) spectra. With the utilization of the ionBooster source, limits for the automated detection comparable to cut-off values of routine MRM methods were achieved for the majority of analytes. Even compounds not identified when using a conventional ESI source were detected using the ionBooster-source. LODs in serum range from 0.1 ng/ml to 0.5 ng/ml. The use of parent compounds as analytical targets offers the possibility of instantly adding new emerging compounds to the library and immediately applying the updated method to serum samples, allowing the rapid adaptation of the screening method to ongoing forensic or clinical requirements. The presented approach can also be applied to other specimens, such as oral fluid or hair, and herbal mixtures and was successfully applied to authentic serum samples. Quantitative MRM results of samples with

  12. Ion trapping in the high-energy storage ring HESR

    Energy Technology Data Exchange (ETDEWEB)

    Hinterberger, Frank [Bonn Univ. (Germany). Helmholtz-Institut fuer Strahlen- und Kernphysik

    2011-10-15

    The problem of ion trapping in the high-energy storage ring HESR is studied in the present report. Positive ions are trapped in the negative potential well of the antiproton beam. The ions are produced by the interaction between the antiproton beam and the residual gas. The adverse effects of ion trapping like tune shifts, tune spreads and coherent instabilities are reviewed. The ion production rate by ionization of the residual gas molecules is estimated. The negative potential well and the corresponding electric fields of the antiproton beam are evaluated in order to study the transverse and longitudinal motion of the ions and the accumulation in trapping pockets. The removal of ions can be achieved using clearing electrodes and under certain conditions resonant transverse beam shaking. Diagnostic tools and measurements of trapped ion effects are sketched. (orig.)

  13. Space-charge effects in Penning ion traps

    Czech Academy of Sciences Publication Activity Database

    Porobic, T.; Beck, M.; Breitenfeldt, M.; Couratin, C.; Finlay, P.; Knecht, A.; Fabian, X.; Friedag, P.; Flechard, X.; Lienard, E.; Ban, G.; Zákoucký, Dalibor; Soti, G.; Van Gorp, S.; Weinheimer, C.; Wursten, E.; Severijns, N.

    2015-01-01

    Roč. 785, JUN (2015), s. 153-162 ISSN 0168-9002 R&D Projects: GA MŠk LA08015; GA MŠk(CZ) LG13031 Institutional support: RVO:61389005 Keywords : Penning trap * space-charge * magnetron motion * ion trapping * buffer gas cooling * ion cyclotron resonance Subject RIV: BG - Nuclear, Atomic and Molecular Physics, Colliders Impact factor: 1.200, year: 2015

  14. Single Ion Trapping for the Enriched Xenon Observatory

    Energy Technology Data Exchange (ETDEWEB)

    Waldman, Samuel J.; /Stanford U., Phys. Dept. /SLAC

    2006-03-28

    In the last decade, a variety of neutrino oscillation experiments have established that there is a mass difference between neutrino flavors, without determining the absolute neutrino mass scale. The Enriched Xenon Observatory for neutrinoless double beta decay (EXO) will search for the rare decays of xenon to determine the absolute value of the neutrino mass. The experiment uses a novel technique to minimize backgrounds, identifying the decay daughter product in real time using single ion spectroscopy. Here, we describe single ion trapping and spectroscopy compatible with the EXO detector. We extend the technique of single ion trapping in ultrahigh vacuum to trapping in xenon gas. With this technique, EXO will achieve a neutrino mass sensitivity of {approx_equal} .010 eV.

  15. Monolithic column in gas chromatography.

    Science.gov (United States)

    Kurganov, A

    2013-05-02

    Monolithic columns invented in chromatographic praxis almost 40 years ago gained nowadays a lot of popularity in separations by liquid chromatographic technique. At the same time, application of monolithic columns in gas chromatography is less common and only a single review published by Svec et al. covers this field of research. Since that time a lot of new findings on application and properties of monolithic columns in gas chromatography have been published in the literature deserving consideration and discussion. This review considers preparation of monolithic columns for GC, an impact of preparation conditions on column performance, optimization of separation conditions for GC analysis on monolithic columns and other important aspects of preparation and usage of monolithic capillary columns in GC. A final part of the review discusses the modern trends and possible applications in the future of capillary monolithic columns in GC. Copyright © 2013 Elsevier B.V. All rights reserved.

  16. Use of a hand-portable gas chromatograph-toroidal ion trap mass spectrometer for self-chemical ionization identification of degradation products related to O-ethyl S-(2-diisopropylaminoethyl) methyl phosphonothiolate (VX)

    International Nuclear Information System (INIS)

    Smith, Philip A.; Lepage, Carmela R. Jackson; Savage, Paul B.; Bowerbank, Christopher R.; Lee, Edgar D.; Lukacs, Michael J.

    2011-01-01

    The chemical warfare agent O-ethyl S-(2-diisopropylaminoethyl) methyl phosphonothiolate (VX) and many related degradation products produce poorly diagnostic electron ionization (EI) mass spectra by transmission quadrupole mass spectrometry. Thus, chemical ionization (CI) is often used for these analytes. In this work, pseudomolecular ([M+H] + ) ion formation from self-chemical ionization (self-CI) was examined for four VX degradation products containing the diisopropylamine functional group. A person-portable toroidal ion trap mass spectrometer with a gas chromatographic inlet was used with EI, and both fixed-duration and feedback-controlled ionization time. With feedback-controlled ionization, ion cooling (reaction) times and ion formation target values were varied. Evidence for protonation of analytes was observed under all conditions, except for the largest analyte, bis(diisopropylaminoethyl)disulfide which yielded [M+H] + ions only with increased fixed ionization or ion cooling times. Analysis of triethylamine-d 15 provided evidence that [M+H] + production was likely due to self-CI. Analysis of a degraded VX sample where lengthened ion storage and feedback-controlled ionization time were used resulted in detection of [M+H] + ions for VX and several relevant degradation products. Dimer ions were also observed for two phosphonate compounds detected in this sample.

  17. Multiresidue determination of 19 fungicides in processed fruits and vegetables by capillary gas chromatography after gel permeation chromatography.

    Science.gov (United States)

    Sannino, A; Bandini, M; Bolzoni, L

    1999-01-01

    A gas chromatographic (GC) method was developed for simultaneous determination of 19 fungicides (chlorothalonil, vinclozolin, dichlofuanid, triadimefon, penconazole, chlozolinate, captan, procymidone, triadimenol, folpet, hexaconazole, myclobutanil, cyproconazole, propiconazole, nuarimol, captafol, iprodione, fenarimol, and bitertanol) and the acaricide tetradifon in tomato puree, peach nectar, orange juice, and canned peas. Samples were extracted with acetone, partitioned with ethyl acetate-cyclohexane (50 + 50, v/v), and cleaned using gel permeation chromatography with ethyl acetate-cyclohexane (50 + 50, v/v) as eluant. The final extract was analyzed by GC with ion trap mass spectrometry (ITMS) using a DB5 capillary column. Recoveries from fortified samples ranged from 74.6 to 99.3%, except for triadimenol and bitertanol. Quantitation limits for most analytes were between 0.005 and 0.050 mg/kg. The purified extracts were analyzed further by GC with electron capture and nitrogen phosphorus detection, and the results were compared with those obtained by ITMS.

  18. Direct trace analysis of metals and alloys in a quadrupole ion-trap mass spectrometer

    CERN Document Server

    Song, K S; Yang, M; Cha, H K; Lee, J M; Lee, G H

    1999-01-01

    An ion-trap mass spectrometer adopting a quadrupole ion-trap and laser ablation/ionization method was constructed. The developed system was tested for composition analysis of some metals (Cu, stainless), and alloys (hastalloy C, mumetal) by mass spectrometry. Samples were analyzed by using laser ablation from a sample probe tip followed by a mass analysis with the quadrupole ion-trap. The quadrupole ion-trap was modified to enable laser ablation by a XeCl excimer laser pulse that passed radially through the ring electrode. A mass scan of the produced ions was performed in the mass selective instability mode wherein trapped ions were successively detected by increasing the rf voltage through the ring electrode. Factors affecting the mass resolution, such as pressure of buffer gas and ablation laser power, are discussed.

  19. Sympathetic cooling of ions in a hybrid atom ion trap

    Energy Technology Data Exchange (ETDEWEB)

    Hoeltkemeier, Bastian

    2016-10-27

    In this thesis the dynamics of a trapped ion immersed in a spatially localized buffer gas is investigated. For a homogeneous buffer gas, the ion's energy distribution reaches a stable equilibrium only if the mass of the buffer gas atoms is below a critical value. This limitation can be overcome by using multipole traps in combination and/or a spatially confined buffer gas. Using a generalized model for elastic collisions of the ion with the buffer gas atoms, the ion's energy distribution is numerically determined for arbitrary buffer gas distributions and trap parameters. Three regimes characterized by the respective analytic form of the ion's equilibrium energy distribution are found. One of these is a novel regime at large atom-to-ion mass ratios where the final ion temperature can tuned by adiabatically decreasing the spatial extension of the buffer gas and the effective ion trap depth (forced sympathetic cooling). The second part of the thesis presents a hybrid atom ion trap designed for sympathetic cooling of hydroxide anions. In this hybrid trap the anions are immersed in a cloud of laser cooled rubidium atoms. The translational and rovibrational temperatures of the anions is probed by photodetachment tomography and spectroscopy which shows the first ever indication of sympathetic cooling of anions by laser cooled atoms.

  20. Finnigan ion trap mass spectrometer detection limits and thermal energy analyzer interface status report and present capabilities

    Energy Technology Data Exchange (ETDEWEB)

    Alcaraz, A.; Andresen, B.; Martin, W.

    1990-10-18

    A new Finnigan ion trap mass spectrometer was purchased and installed at LLNL. Over a period of several months the instrument was tested under a variety of conditions utilizing a capillary gas chromatography interface which allowed separated organic compounds to be carried directly into the ion source of the mass spectrometer. This direct interface allowed maximum analytical sensitivity. A variety of critical tests were performed in order to optimize the sensitivity of the system under a variety of analysis conditions. These tests altered the critical time cycles of the ionization, ion trapping, and detection. Various carrier gas pressures were also employed in order to ascertain the overall sensitivity of the instrument. In addition we have also interfaced a thermal energy analyzer (TEA) to the gas chromatograph in order to simultaneously detect volatile nitrogen containing compounds while mass spectral data is being acquired. This is the first application at this laboratory of simultaneous ultra-trace detections while utilizing two orthogonal analytical techniques. In particular, explosive-related compound and/or residues are of interest to the general community in water, soil and gas sampler. In this paper are highlighted a few examples of the analytical power of this new GC-TEA-ITMS technology.

  1. Simultaneous quantification of poly-dispersed anionic, amphoteric and nonionic surfactants in simulated wastewater samples using C18 high-performance liquid chromatography-quadrupole ion-trap mass spectrometry

    Science.gov (United States)

    Levine, Lanfang H.; Garland, Jay L.; Johnson, Jodie V.

    2005-01-01

    This paper describes the development of a guantitative method for direct and simultaneous determination of three frequently encountered surfactants, amphoteric (cocoamphoacetate, CAA), anionic (sodium laureth sulfate, SLES), and nonionic (alcohol ethoxylate, AE) using a reversed-phase C18 HPLC coupled with an ESI ion-trap mass spectrometer (MS). Chemical composition, ionization characteristics and fragmentation pathways of the surfactants are presented. Positive ESI was effective for all three surfactants in agueous methanol buffered with ammonium acetate. The method enables rapid determinations in small sample volumes containing inorganic salts (up to 3.5 g L(-1)) and multiple classes of surfactants with high specificity by applying surfactant specific tandem mass spectrometric strategies. It has dynamic linear ranges of 2-60, 1.5-40, 0.8-56 mg L(-1) with R2 egual or greater than 0.999, 0.98 and 0.999 (10 microL injection) for CAA, SLES, and AE, respectively.

  2. Suitability of an ion trap GC/MS/MS method for routine analysis of PCDD/Fs in fishery products and by-products

    Energy Technology Data Exchange (ETDEWEB)

    Sobrado, C.; Quintela, C.; Blanco, L.; Gonzalez, J.C.; Vieites, J.M. [ANFACO-CECOPESCA, Vigo (Spain); Cabaleiro, S. [CETGA, Riveira (Spain)

    2004-09-15

    Fishery products and by-products constitute an important vector of dioxins towards humans due to bioacumulation and biomagnification, so fish processing industry is highly interested in the development of analytical procedures cheaper and faster than the the standard HRGCHRMS. The aim of this study was to demonstrate the suitability of a method of determination of the 17 congeners of dioxins and furans in fishery products and by-products, using a high resolution gas chromatography connected to an ion trap tandem mass spectrometer (HRGCMS/ MS) based on the patern of fragmentation of the congeners by MS/MS and quantification by isotope dilution.

  3. Electrostatic interactions in gas-solid chromatography.

    Science.gov (United States)

    Benson, S. W.; King, J., Jr.

    1966-01-01

    Electrostatic theory of physical adsorption applied to gas-solid chromatography, discussing chromatographic inseparability of argon and oxygen at room temperature, prediction of elution order of many gases, etc

  4. Elucidation of urinary metabolites of fluoxymesterone by liquid chromatography-tandem mass spectrometry and gas chromatography-mass spectrometry.

    Science.gov (United States)

    Pozo, Oscar J; Van Thuyne, Wim; Deventer, Koen; Van Eenoo, Peter; Delbeke, Frans T

    2008-03-01

    The suitability of liquid chromatography tandem mass spectrometry (LC-MS/MS) and gas chromatography mass spectrometry (GC-MS) for the elucidation of fluoxymesterone metabolism has been evaluated. Electrospray ionization (ESI) and collision induced dissociation (CID) fragmentation in LC-MS/MS and electron impact spectra (EI) in GC-MS have been studied for fluoxymesterone and two commercially available metabolites. MS(n) experiments and accurate mass measurements performed by an ion-trap analyser and a QTOF instrument respectively have been used for the elucidation of the fragmentation pathway. The neutral loss scan of 20 Da (loss of HF) in LC-MS/MS has been applied for the selective detection of fluoxymesterone metabolites. In a positive fluoxymesterone doping control sample, 9 different analytes have been detected including the parent compound. Seven of these metabolites were also confirmed by GC-MS including 5 previously unreported metabolites. On the basis of the ionization, the CID fragmentation, the accurate mass of the product ions and the EI spectra of these analytes, a tentative elucidation as well as a proposal for the metabolic pathway of fluoxymesterone has been suggested. The presence of these compounds has also been confirmed by the analysis of five other positive fluoxymesterone urine samples. Copyright (c) 2008 John Wiley & Sons, Ltd.

  5. Gas chromatography at the Tritium Laboratory Karlsruhe

    International Nuclear Information System (INIS)

    Laesser, R.; Gruenhagen, S.

    2003-08-01

    Among the analytical techniques (mass spectrometry, laser Raman spectroscopy, gas chromatography, use of ionisation chambers) employed at the Tritium Laboratory Karlsruhe (TLK), gas chromatography plays a prominent role. The main reasons for that are the simplicity of the gas chromatographic separation process, the small space required for the equipment, the low investment costs in comparison to other methods, the robustness of the equipment, the simple and straightforward analysis and the fact that all gas species of interest (with the exception of water) can easily be detected by gas chromatographic means. The conventional gas chromatographs GC1 and GC2 used in the Tritium Measurement Techniques (TMT) System of the TLK and the gas chromatograph GC3 of the experiment CAPER are presented in detail, by discussing their flow diagrams, their major components, the chromatograms measured by means of various detectors, shortcomings and possible improvements. One of the main disadvantages of the conventional gas chromatography is the long retention times required for the analysis of hydrogen gas mixtures. To overcome this disadvantage, micro gas chromatography for hydrogen analysis was developed. Reduction of the retention times by one order of magnitude was achieved. (orig.)

  6. Microfabricated Microwave-Integrated Surface Ion Trap

    Science.gov (United States)

    Revelle, Melissa C.; Blain, Matthew G.; Haltli, Raymond A.; Hollowell, Andrew E.; Nordquist, Christopher D.; Maunz, Peter

    2017-04-01

    Quantum information processing holds the key to solving computational problems that are intractable with classical computers. Trapped ions are a physical realization of a quantum information system in which qubits are encoded in hyperfine energy states. Coupling the qubit states to ion motion, as needed for two-qubit gates, is typically accomplished using Raman laser beams. Alternatively, this coupling can be achieved with strong microwave gradient fields. While microwave radiation is easier to control than a laser, it is challenging to precisely engineer the radiated microwave field. Taking advantage of Sandia's microfabrication techniques, we created a surface ion trap with integrated microwave electrodes with sub-wavelength dimensions. This multi-layered device permits co-location of the microwave antennae and the ion trap electrodes to create localized microwave gradient fields and necessary trapping fields. Here, we characterize the trap design and present simulated microwave performance with progress towards experimental results. This research was funded, in part, by the Office of the Director of National Intelligence (ODNI), Intelligence Advanced Research Projects Activity (IARPA).

  7. Linear Ion Trap for the Mars Organic Molecule Analyzer

    Science.gov (United States)

    Brinckerhoff, William; Arevalo, Ricardo; Danell, Ryan; van Amerom, Friso; Pinnick, Veronica; Li, Xiang; Hovmand, Lars; Getty, Stephanie; Mahaffy, Paul; Goesmann, Fred; Steininger, Harald

    2014-05-01

    The 2018 ExoMars rover mission includes the Mars Organic Molecule Analyzer (MOMA) investigation. MOMA will examine the chemical composition of samples acquired from depths of up to two meters below the martian surface, where organics may be protected from radiative and oxidative degradation. When combined with the complement of instruments in the rover's Pasteur Payload, MOMA has the potential to reveal the presence of a wide range of organics preserved in a variety of mineralogical environments, and to begin to understand the structural character and potential origin of those compounds. MOMA includes a linear, or 2D, ion trap mass spectrometer (ITMS) that is designed to analyze molecular composition of (i) gas evolved from pyrolyzed powder samples and separated on a gas chromatograph and (ii) ions directly desorbed from solid samples at Mars ambient pressure using a pulsed laser and a fast-valve capillary ion inlet system. This "dual source" approach gives MOMA unprecedented breadth of detection over a wide range of molecular weights and volatilities. Analysis of nonvolatile, higher-molecular weight organics such as carboxylic acids and peptides even in the presence of significant perchlorate concentrations is enabled by the extremely short (~1 ns) pulses of the desorption laser. Use of the ion trap's tandem mass spectrometry mode permits selective focus on key species for isolation and controlled fragmentation, providing structural analysis capabilities. The flight-like engineering test unit (ETU) of the ITMS, now under construction, will be used to verify breadboard performance with high fidelity, while simultaneously supporting the development of analytical scripts and spectral libraries using synthetic and natural Mars analog samples guided by current results from MSL. ETU campaign data will strongly advise the specifics of the calibration applied to the MOMA flight model as well as the science operational procedures during the mission.

  8. Ion funnel ion trap and process

    Science.gov (United States)

    Belov, Mikhail E [Richland, WA; Ibrahim, Yehia M [Richland, WA; Clowers, Biran H [West Richland, WA; Prior, David C [Hermiston, OR; Smith, Richard D [Richland, WA

    2011-02-15

    An ion funnel trap is described that includes a inlet portion, a trapping portion, and a outlet portion that couples, in normal operation, with an ion funnel. The ion trap operates efficiently at a pressure of .about.1 Torr and provides for: 1) removal of low mass-to-charge (m/z) ion species, 2) ion accumulation efficiency of up to 80%, 3) charge capacity of .about.10,000,000 elementary charges, 4) ion ejection time of 40 to 200 .mu.s, and 5) optimized variable ion accumulation times. Ion accumulation with low concentration peptide mixtures has shown an increase in analyte signal-to-noise ratios (SNR) of a factor of 30, and a greater than 10-fold improvement in SNR for multiply charged analytes.

  9. Quasi-conical centrifugal ion trap

    International Nuclear Information System (INIS)

    Golikov, Yu.K.; Solov'ev, K.V.; Grigor'ev, D.V.; Flegontova, E.Yu.

    1999-01-01

    This paper describes a new excellent ion trap that principally differs from the classic hyperbolic one by its action. The action is based on the axisymmetric electrostatic quasi-conical field with the following potential type: F=F 0 [ln r - r 2 /2+z 2 ], where r, z are cylindrical dimensionless coordinates. The radial potential run (f=ln r-r 2 /2), in this case, is exactly presented by the approximation function f a =ar 2 +b/r 2 +c. In addition, there are some ranges of r (for example, 0.6< r<0.35), in which the concurrence accuracy value is above 0.5%. The paper presents the theory of particles dynamics in the centrifugal trap. Basic correlation for resolution ratios and sensitivity values are developed. Recommendations on the centrifugal trap design implementation, including the recording system, are given

  10. Ion trap architectures and new directions

    Science.gov (United States)

    Siverns, James D.; Quraishi, Qudsia

    2017-12-01

    Trapped ion technology has seen advances in performance, robustness and versatility over the last decade. With increasing numbers of trapped ion groups worldwide, a myriad of trap architectures are currently in use. Applications of trapped ions include: quantum simulation, computing and networking, time standards and fundamental studies in quantum dynamics. Design of such traps is driven by these various research aims, but some universally desirable properties have lead to the development of ion trap foundries. Additionally, the excellent control achievable with trapped ions and the ability to do photonic readout has allowed progress on quantum networking using entanglement between remotely situated ion-based nodes. Here, we present a selection of trap architectures currently in use by the community and present their most salient characteristics, identifying features particularly suited for quantum networking. We also discuss our own in-house research efforts aimed at long-distance trapped ion networking.

  11. Application of gas chromatography in hydrogen isotope separation

    International Nuclear Information System (INIS)

    Ye Xiaoqiu; Sang Ge; Peng Lixia; Xue Yan; Cao Wei

    2008-01-01

    The principle of gas chromatographic separation of hydrogen isotopes was briefly introduced. The main technology and their development of separating hydrogen isotopes, including elution chromatography, hydrogen-displacement chromatography, self-displacement chromatography and frontal chromatography were discussed in detail. The prospect of hydrogen isotope separation by gas chromatography was presented. (authors)

  12. Capillary gas chromatography in essential oil analysis

    Energy Technology Data Exchange (ETDEWEB)

    Sandra, P.; Bicchi, C. (eds.)

    1987-01-01

    Capillary GC has strongly contributed to the development of essential oil science both from an industrial point of view (quality control, new sources of odoriferous compounds) and from a scientific point of view (phytochemistry, chemotaxonomy, biochemistry, etc). The reserve, however, is also true. Essential oil research has contributed to the present state of the art in capillary gas chromatography, e.g. the polar and sometimes thermolabile character of essential oil components has emphasized the need for more inert capillary columns and better sample introduction systems, selective polar phases have been developed, etc. Within 14 separate contributions of the book the following topics are discussed: general aspects of essential oil preparation and analysis, considerations on the selection of capillary columns for the analysis, microtechniques, headspace versus classical analysis, 'fingerprints', industrial quality control, retention indices, dual channel analysis, gas chromatography-mass spectroscopy coupling, examples of artefact formation, GC-FTIR analysis, multidimensional gas chromatography.

  13. Temperature programmable microfabricated gas chromatography column

    Science.gov (United States)

    Manginell, Ronald P.; Frye-Mason, Gregory C.

    2003-12-23

    A temperature programmable microfabricated gas chromatography column enables more efficient chemical separation of chemical analytes in a gas mixture by the integration of a resistive heating element and temperature sensing on the microfabricated column. Additionally, means are provided to thermally isolate the heated column from their surroundings. The small heat capacity and thermal isolation of the microfabricated column improves the thermal time response and power consumption, both important factors for portable microanalytical systems.

  14. Some recent developments in headspace gas chromatography

    Science.gov (United States)

    J.Y. Zhu; X.-S. Chai

    2005-01-01

    In this study, recent developments in headspace gas chromatography (HSGC) are briefly reviewed. Several novel HSGC techniques developed recently are presented in detail. These techniques were developed using the unique characteristics of the headspace sampling process implemented in commercial HSGC systems and therefore can be easily applied in laboratory and...

  15. Highly charged ions trapping for lifetime measurements

    International Nuclear Information System (INIS)

    Attia, D.

    2007-10-01

    A new experimental setup dedicated to highly charged ion trapping is presented in this work. The final goal is to perform lifetime measurement of metastable states produced by our ECR (Electron Cyclotron Resonance) ion source. Lifetimes to be measured are in the range of a few ms and more. We have measured the lifetimes of the M1 transitions of the metastable states of Ar 9+ , Ar 13+ and Ar 14+ . These measurements are useful to test the N-body problem in the relativistic range. The trap we have built, was designed a few years ago at the Weizman Institute in Israel, it allows ions with an energy of several keV to be trapped for lifetimes of about 1 second. This trap was originally designed to study the dynamics of excited molecules. We have shown for the first time how the trap operates and that it can operate with highly charged ions. We have studied the beam dynamics of highly charged ions and the trap has been tested with various species of ions and different charge states: from O + to O 6+ , from Ar 8+ to Ar 13+ , and from Kr 13+ to Kr 20+

  16. Comparative determination of phenytoin by spectrophotometry, gas chromatography, liquid chromatography, enzyme immunoassay, and radioimmunoassay

    International Nuclear Information System (INIS)

    Castro, A.; Ibanez, J.; DiCesare, J.L.; Adams, R.F.; Malkus, H.

    1978-01-01

    Sera from patients being treated with phenytoin were analyzed for the drug by spectrophotometry, gas chromatography, radioimmunoasay, enzyme immunoassay, and liquid chromatography. The assay values obtained were intercompared statistically. Enzyme immunoassay and liquid chromatography appear to be attractive alternatives to the more traditional methods of spectrophotometry and gas chromatography. Our radioimmunoassay data correlated poorly with results by the four other methods

  17. Quantitative determination of multi markers in five varieties of Withania somnifera using ultra-high performance liquid chromatography with hybrid triple quadrupole linear ion trap mass spectrometer combined with multivariate analysis: Application to pharmaceutical dosage forms.

    Science.gov (United States)

    Chandra, Preeti; Kannujia, Rekha; Saxena, Ankita; Srivastava, Mukesh; Bahadur, Lal; Pal, Mahesh; Singh, Bhim Pratap; Kumar Ojha, Sanjeev; Kumar, Brijesh

    2016-09-10

    An ultra-high performance liquid chromatography electrospray ionization tandem mass spectrometry method has been developed and validated for simultaneous quantification of six major bioactive compounds in five varieties of Withania somnifera in various plant parts (leaf, stem and root). The analysis was accomplished on Waters ACQUITY UPLC BEH C18 column with linear gradient elution of water/formic acid (0.1%) and acetonitrile at a flow rate of 0.3mLmin(-1). The proposed method was validated with acceptable linearity (r(2), 0.9989-0.9998), precision (RSD, 0.16-2.01%), stability (RSD, 1.04-1.62%) and recovery (RSD ≤2.45%), under optimum conditions. The method was also successfully applied for the simultaneous determination of six marker compounds in twenty-six marketed formulations. Hierarchical cluster analysis and principal component analysis were applied to discriminate these twenty-six batches based on characteristics of the bioactive compounds. The results indicated that this method is advance, rapid, sensitive and suitable to reveal the quality of Withania somnifera and also capable of performing quality evaluation of polyherbal formulations having similar markers/raw herbs. Copyright © 2016 Elsevier B.V. All rights reserved.

  18. A Simple Defined Medium for the Production of True Diketopiperazines in Xylella fastidiosa and Their Identification by Ultra-Fast Liquid Chromatography-Electrospray Ionization Ion Trap Mass Spectrometry

    Directory of Open Access Journals (Sweden)

    Michelli Massaroli da Silva

    2017-06-01

    Full Text Available Diketopiperazines can be generated by non-enzymatic cyclization of linear dipeptides at extreme temperature or pH, and the complex medium used to culture bacteria and fungi including phytone peptone and trypticase peptone, can also produce cyclic peptides by heat sterilization. As a result, it is not always clear if many diketopiperazines reported in the literature are artifacts formed by the different complex media used in microorganism growth. An ideal method for analysis of these compounds should identify whether they are either synthesized de novo from the products of primary metabolism and deliver true diketopiperazines. A simple defined medium (X. fastidiosa medium or XFM containing a single carbon source and no preformed amino acids has emerged as a method with a particularly high potential for the grown of X. fastidiosa and to produce genuine natural products. In this work, we identified a range of diketopiperazines from X. fastidiosa 9a5c growth in XFM, using Ultra-Fast Liquid Chromatography coupled with mass spectrometry. Diketopiperazines are reported for the first time from X. fastidiosa, which is responsible for citrus variegated chlorosis. We also report here fatty acids from X. fastidiosa, which were not biologically active as diffusible signals, and the role of diketopiperazines in signal transduction still remains unknown.

  19. A Simple Defined Medium for the Production of True Diketopiperazines in Xylella fastidiosa and Their Identification by Ultra-Fast Liquid Chromatography-Electrospray Ionization Ion Trap Mass Spectrometry.

    Science.gov (United States)

    Silva, Michelli Massaroli da; Andrade, Moacir Dos Santos; Bauermeister, Anelize; Merfa, Marcus Vinícius; Forim, Moacir Rossi; Fernandes, João Batista; Vieira, Paulo Cezar; Silva, Maria Fátima das Graças Fernandes da; Lopes, Norberto Peporine; Machado, Marcos Antônio; Souza, Alessandra Alves de

    2017-06-13

    Diketopiperazines can be generated by non-enzymatic cyclization of linear dipeptides at extreme temperature or pH, and the complex medium used to culture bacteria and fungi including phytone peptone and trypticase peptone, can also produce cyclic peptides by heat sterilization. As a result, it is not always clear if many diketopiperazines reported in the literature are artifacts formed by the different complex media used in microorganism growth. An ideal method for analysis of these compounds should identify whether they are either synthesized de novo from the products of primary metabolism and deliver true diketopiperazines. A simple defined medium ( X. fastidiosa medium or XFM) containing a single carbon source and no preformed amino acids has emerged as a method with a particularly high potential for the grown of X. fastidiosa and to produce genuine natural products. In this work, we identified a range of diketopiperazines from X. fastidiosa 9a5c growth in XFM, using Ultra-Fast Liquid Chromatography coupled with mass spectrometry. Diketopiperazines are reported for the first time from X. fastidiosa , which is responsible for citrus variegated chlorosis. We also report here fatty acids from X. fastidiosa , which were not biologically active as diffusible signals, and the role of diketopiperazines in signal transduction still remains unknown.

  20. Ionization-based detectors for gas chromatography.

    Science.gov (United States)

    Poole, Colin F

    2015-11-20

    The gas phase ionization detectors are the most widely used detectors for gas chromatography. The column and makeup gases commonly used in gas chromatography are near perfect insulators. This facilitates the detection of a minute number of charge carriers facilitating the use of ionization mechanisms of low efficiency while providing high sensitivity. The main ionization mechanism discussed in this report are combustion in a hydrogen diffusion flame (flame ionization detector), surface ionization in a plasma (thermionic ionization detector), photon ionization (photoionization detector and pulsed discharge helium ionization detector), attachment of thermal electrons (electron-capture detector), and ionization by collision with metastable helium species (helium ionization detector). The design, response characteristics, response mechanism, and suitability for fast gas chromatography are the main features summarized in this report. Mass spectrometric detection and atomic emission detection, which could be considered as ionization detectors of a more sophisticated and complex design, are not discussed in this report. Copyright © 2015 Elsevier B.V. All rights reserved.

  1. Modular Universal Scalable Ion-trap Quantum Computer

    Science.gov (United States)

    2016-06-02

    trap quantum computer . This architecture has two separate layers of scalability: the first is to increase the number of ion qubits in a single trap...Distribution Unlimited UU UU UU UU 02-06-2016 1-Aug-2010 31-Jan-2016 Final Report: Modular Universal Scalable Ion-trap Quantum Computer The views...P.O. Box 12211 Research Triangle Park, NC 27709-2211 Ion trap quantum computation , scalable modular architectures REPORT DOCUMENTATION PAGE 11

  2. Improved Thermal Modulator for Gas Chromatography

    Science.gov (United States)

    Hasselbrink, Ernest Frederick, Jr.; Hunt, Patrick J.; Sacks, Richard D.

    2008-01-01

    An improved thermal modulator has been invented for use in a variant of gas chromatography (GC). The variant in question denoted as two-dimensional gas chromatography (2DGC) or GC-GC involves the use of three series-connected chromatographic columns, in the form of capillary tubes coated interiorly with suitable stationary phases (compounds for which different analytes exhibit different degrees of affinity). The two end columns are relatively long and are used as standard GC columns. The thermal modulator includes the middle column, which is relatively short and is not used as a standard GC column: instead, its temperature is modulated to affect timed adsorption and desorption of analyte gases between the two end columns in accordance with a 2DGC protocol.

  3. Flow Rates in Liquid Chromatography, Gas Chromatography and Supercritical Fluid Chromatography: A Tool for Optimization

    Directory of Open Access Journals (Sweden)

    Joris Meurs

    2016-08-01

    Full Text Available This paper aimed to develop a standalone application for optimizing flow rates in liquid chromatography (LC, gas chromatography (GC and supercritical fluid chromatography (SFC. To do so, Van Deemter’s equation, Knox’ equation and Golay’s equation were implemented in a MATLAB script and subsequently a graphical user interface (GUI was created. The application will show the optimal flow rate or linear velocity and the corresponding plate height for the set input parameters. Furthermore, a plot will be shown in which the plate height is plotted against the linear flow velocity. Hence, this application will give optimized flow rates for any set conditions with minimal effort.

  4. IMPROVEMENT OF THE CERN SPS ELECTROSTATIC SEPTA ION TRAPS

    CERN Multimedia

    Balhan, Bruno; Barlow, Roger Andrew; Raffaele, Graziano

    2016-01-01

    At CERN, the SPS synchrotron is equipped with a slow extraction channel towards the fixed target beam lines in the North Area This channel includes five consecutive electrostatic septa, where the field free region and the active high field region are separated by an array of tungsten-rhenium wires. The field-free region provides for the circulating beam, while the high field region is used to deflect the extracted beam. Since the residual gas can be ionized by the orbiting beam, low energy ions could cross the wire array and enter the high field region and cause high voltage breakdown when accelerated onto the cathode. To prevent low energy ions from entering this high electric field region, a vertical field is applied to the orbiting beam using so-called ‘ion traps’ for active protection. The vertical field is created by electrodes placed inside the region containing the circulating beam. Due to electromagnetic coupling onto the ion trap electrodes observed with the high frequency LHC beam (25 ns spaced ...

  5. Vibrational Cooling in A Cold Ion Trap: Vibrationally Resolved Photoelectron Spectroscopy of Cold C60- Anions

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Xue B.; Woo, Hin-koon; Wang, Lai S.

    2005-08-01

    We demonstrate vibrational cooling of anions via collisions with a background gas in an ion trap attached to a cryogenically controlled cold head (10 ? 400 K). Photoelectron spectra of vibrationally cold C60- anions, produced by electrospray ionization and cooled in the cold ion trap, have been obtained. Relative to spectra taken at room temperature, vibrational hot bands are completely eliminated, yielding well resolved vibrational structures and a more accurate electron affinity for neutral C60. The electron affinity of C60 is measured to be 2.683 ? 0.008 eV. The cold spectra reveal complicated vibrational structures for the transition to the C60 ground state due to the Jahn-Teller effect in the ground state of C60-. Vibrational excitations in the two Ag modes and eight Hg modes are observed, providing ideal data to assess the vibronic couplings in C60-.

  6. Evolved gas composition monitoring by repetitive injection gas chromatography.

    Science.gov (United States)

    White, Robert L

    2015-11-20

    Performance characteristics and applications of a small volume gas chromatograph oven are described. Heating and cooling properties of the apparatus are evaluated and examples are given illustrating the advantages of greatly reducing the air bath volume surrounding fused silica columns. Fast heating and cooling of the oven permit it to be employed for repetitive injection analyses. By using fast gas chromatography separations to achieve short assay cycle times, the apparatus can be employed for on-line species-specific gas stream composition monitoring when volatile species concentrations vary on time scales of a few minutes or longer. This capability facilitates repeated sampling and fast gas chromatographic separations of volatile product mixtures produced during thermal analyses. Applications of repetitive injection gas chromatography-mass spectrometry evolved gas analyses to monitoring purge gas effluent streams containing volatile acid catalyzed polymer cracking products are described. The influence of thermal analysis and chromatographic experimental parameters on effluent sampling frequency are delineated. Copyright © 2015 Elsevier B.V. All rights reserved.

  7. Atomic ion clock with two ion traps, and method to transfer ions

    Science.gov (United States)

    Prestage, John D. (Inventor); Chung, Sang K. (Inventor)

    2011-01-01

    An atomic ion clock with a first ion trap and a second ion trap, where the second ion trap is of higher order than the first ion trap. In one embodiment, ions may be shuttled back and forth from one ion trap to the other by application of voltage ramps to the electrodes in the ion traps, where microwave interrogation takes place when the ions are in the second ion trap, and fluorescence is induced and measured when the ions are in the first ion trap. In one embodiment, the RF voltages applied to the second ion trap to contain the ions are at a higher frequency than that applied to the first ion trap. Other embodiments are described and claimed.

  8. Permanent gas analysis using gas chromatography with vacuum ultraviolet detection.

    Science.gov (United States)

    Bai, Ling; Smuts, Jonathan; Walsh, Phillip; Fan, Hui; Hildenbrand, Zacariah; Wong, Derek; Wetz, David; Schug, Kevin A

    2015-04-03

    The analysis of complex mixtures of permanent gases consisting of low molecular weight hydrocarbons, inert gases, and toxic species plays an increasingly important role in today's economy. A new gas chromatography detector based on vacuum ultraviolet (VUV) spectroscopy (GC-VUV), which simultaneously collects full scan (115-240 nm) VUV and UV absorption of eluting analytes, was applied to analyze mixtures of permanent gases. Sample mixtures ranged from off-gassing of decomposing Li-ion and Li-metal batteries to natural gas samples and water samples taken from private wells in close proximity to unconventional natural gas extraction. Gas chromatography separations were performed with a porous layer open tubular column. Components such as C1-C5 linear and branched hydrocarbons, water, oxygen, and nitrogen were separated and detected in natural gas and the headspace of natural gas-contaminated water samples. Of interest for the transport of lithium batteries were the detection of flammable and toxic gases, such as methane, ethylene, chloromethane, dimethyl ether, 1,3-butadiene, CS2, and methylproprionate, among others. Featured is the capability for deconvolution of co-eluting signals from different analytes. Copyright © 2015 Elsevier B.V. All rights reserved.

  9. Comprehensive Gas Chromatography: Food and Metabolomocs Applications.

    Science.gov (United States)

    Strączyński, Grzegorz; Ligor, Tomasz

    2017-10-30

    Since the comprehensive two-dimensional gas chromatography (GC × GC) technique is becoming more and more available for scientists as well as for laboratories performing routine analyses, the most successful field of applications are petrochemical, food and essential oil analysis. However, this technique coupled with TOF-MS (P.1, l. 27) could be even more successfully used in the field of metabolomics. The review presents briefly the concept of comprehensive 2D GC and the principles of the technique. Certain specific applications are discussed to show the usefulness of GC × GC combined with different detectors for determination of compounds not always easy to measure with other techniques.

  10. Clinical applications of gas chromatography and gas chromatography-mass spectrometry of steroids

    NARCIS (Netherlands)

    Wolthers, BG; Kraan, GPB

    1999-01-01

    This review article underlines the importance of gas chromatography-mass spectrometry (GC-MS) for determination of steroids in man. The use of steroids labelled with stable isotopes as internal standard and subsequent analysis by GC-MS yields up to now the only reliable measurement of steroids in

  11. Parallel comprehensive two-dimensional gas chromatography.

    Science.gov (United States)

    Yan, DanDan; Tedone, Laura; Koutoulis, Anthony; Whittock, Simon P; Shellie, Robert A

    2017-11-17

    We introduce an information rich analytical approach called parallel comprehensive two-dimensional gas chromatography (2GC×2GC). This parallel chromatography approach splits injected samples into two independent two-dimensional column ensembles and provides two GC×GC separations by using contra-directional thermal modulation. The first-dimension ( 1 D) and second-dimension ( 2 D) columns are connected using planar three-port microchannel devices, which are supplied with supplementary flow via two pressure controller modules. Precise carrier gas flow control at the junction of the 1 D and 2 D columns permits independent control of flow conditions in each separation column. The 2GC×2GC approach provides two entirely independent GC×GC separations for each injection. Analysis of hop (Humulus lupulus L.) essential oils is used to demonstrate the capability of the approach. The analytical performance of each GC×GC separation in the 2GC×2GC experiment is comparable to individual GC×GC separation with matching column configurations. The peak capacity of 2GC×2GC is about 2 times than that of single GC×GC system. The dual 2D chromatograms produced by this single detector system provide complementary separations and additional identification information by harnessing different selectivity provided by the four separation columns. Copyright © 2017 Elsevier B.V. All rights reserved.

  12. Scalable error correction in distributed ion trap computers

    International Nuclear Information System (INIS)

    Oi, Daniel K. L.; Devitt, Simon J.; Hollenberg, Lloyd C. L.

    2006-01-01

    A major challenge for quantum computation in ion trap systems is scalable integration of error correction and fault tolerance. We analyze a distributed architecture with rapid high-fidelity local control within nodes and entangled links between nodes alleviating long-distance transport. We demonstrate fault-tolerant operator measurements which are used for error correction and nonlocal gates. This scheme is readily applied to linear ion traps which cannot be scaled up beyond a few ions per individual trap but which have access to a probabilistic entanglement mechanism. A proof-of-concept system is presented which is within the reach of current experiment

  13. CrossRef Space-charge effects in Penning ion traps

    CERN Document Server

    Porobić, T; Breitenfeldt, M; Couratin, C; Finlay, P; Knecht, A; Fabian, X; Friedag, P; Fléchard, X; Liénard, E; Ban, G; Zákoucký, D; Soti, G; Van Gorp, S; Weinheimer, Ch; Wursten, E; Severijns, N

    2015-01-01

    The influence of space-charge on ion cyclotron resonances and magnetron eigenfrequency in a gas-filled Penning ion trap has been investigated. Off-line measurements with View the MathML source using the cooling trap of the WITCH retardation spectrometer-based setup at ISOLDE/CERN were performed. Experimental ion cyclotron resonances were compared with ab initio Coulomb simulations and found to be in agreement. As an important systematic effect of the WITCH experiment, the magnetron eigenfrequency of the ion cloud was studied under increasing space-charge conditions. Finally, the helium buffer gas pressure in the Penning trap was determined by comparing experimental cooling rates with simulations.

  14. Dielectronic recombination measurements using the Electron Beam Ion Trap

    International Nuclear Information System (INIS)

    Knapp, D.A.

    1991-01-01

    We have used the Electron Beam Ion Trap at LLNL to study dielectronic recombination in highly charged ions. Our technique is unique because we observe the x-rays from dielectronic recombination at the same time we see x-rays from all other electron-ion interactions. We have recently taken high-resolution, state-selective data that resolves individual resonances

  15. Observation and mitigation of ion trapping in Indus-2

    Indian Academy of Sciences (India)

    of betatron tune, beam instabilities etc. This paper discusses the effects of ion trapping and its mitigation in Indus-2 electron storage ring. Ion-induced instability generating partial beam loss is one of the main barriers in higher beam current accumulation in any electron storage ring. Though there are several techniques to ...

  16. Atomic physics measurements in an electron beam ion trap

    Science.gov (United States)

    Marrs, R. E.; Beiersdorfer, P.; Bennett, C.; Chen, M. H.; Cowan, T.; Dietrich, D.; Henderson, J. R.; Knapp, D. A.; Osterheld, S.; Schneider, M. B.; Scofield, J. H.; Levine, M. A.

    1989-06-01

    An electron Beam Ion Trap at Lawrence Livermore National Laboratory is being used to produce and trap very-highly-charged ions (q≥70+) for x-ray spectroscopy measurements. Recent measurements of transition energies and electron excitation cross sections for x-ray line emission are summarized.

  17. Differentially pumped dual linear quadrupole ion trap mass spectrometer

    Science.gov (United States)

    Owen, Benjamin C.; Kenttamaa, Hilkka I.

    2015-10-20

    The present disclosure provides a new tandem mass spectrometer and methods of using the same for analyzing charged particles. The differentially pumped dual linear quadrupole ion trap mass spectrometer of the present disclose includes a combination of two linear quadrupole (LQIT) mass spectrometers with differentially pumped vacuum chambers.

  18. Nano-Optomechanical Systems for Gas Chromatography.

    Science.gov (United States)

    Venkatasubramanian, Anandram; Sauer, Vincent T K; Roy, Swapan K; Xia, Mike; Wishart, David S; Hiebert, Wayne K

    2016-11-09

    Microgas chromatography (GC) is promising for portable chemical analysis. We demonstrate a nano-optomechanical system (NOMS) as an ultrasensitive mass detector in gas chromatography. Bare, native oxide, silicon surfaces are sensitive enough to monitor volatile organic compounds at ppm levels, while simultaneously demonstrating chemical selectivity. The NOMS is able to sense GC peaks from derivatized metabolites at physiological concentrations. This is an important milestone for small-molecule quantitation assays in next generation metabolite analyses for applications such as disease diagnosis and personalized medicine. The optical microring, which plays an important role in the nanomechanical signal transduction mechanism, can also be used as an analyte concentration sensor. Different adsorption kinetics regimes are realized at different temperatures allowing temporary condensation of the analyte onto the sensor surfaces. This effect amplifies the signal, resulting in a 1 ppb level limit of detection, without partition enhancement from absorbing media. This sensitivity bodes well for NOMS as universal, ultrasensitive detectors in micro-GC, breath analysis, and other chemical-sensing applications.

  19. Vacuum ultraviolet detector for gas chromatography.

    Science.gov (United States)

    Schug, Kevin A; Sawicki, Ian; Carlton, Doug D; Fan, Hui; McNair, Harold M; Nimmo, John P; Kroll, Peter; Smuts, Jonathan; Walsh, Phillip; Harrison, Dale

    2014-08-19

    Analytical performance characteristics of a new vacuum ultraviolet (VUV) detector for gas chromatography (GC) are reported. GC-VUV was applied to hydrocarbons, fixed gases, polyaromatic hydrocarbons, fatty acids, pesticides, drugs, and estrogens. Applications were chosen to feature the sensitivity and universal detection capabilities of the VUV detector, especially for cases where mass spectrometry performance has been limited. Virtually all chemical species absorb and have unique gas phase absorption cross sections in the approximately 120-240 nm wavelength range monitored. Spectra are presented, along with the ability to use software for deconvolution of overlapping signals. Some comparisons with experimental synchrotron data and computed theoretical spectra show good agreement, although more work is needed on appropriate computational methods to match the simultaneous broadband electronic and vibronic excitation initiated by the deuterium lamp. Quantitative analysis is governed by Beer-Lambert Law relationships. Mass on-column detection limits reported for representatives of different classes of analytes ranged from 15 (benzene) to 246 pg (water). Linear range measured at peak absorption for benzene was 3-4 orders of magnitude. Importantly, where absorption cross sections are known for analytes, the VUV detector is capable of absolute determination (without calibration) of the number of molecules present in the flow cell in the absence of chemical interferences. This study sets the stage for application of GC-VUV technology across a wide breadth of research areas.

  20. Performance of the linear ion trap Orbitrap mass analyzer for qualitative and quantitative analysis of drugs of abuse and relevant metabolites in sewage water

    NARCIS (Netherlands)

    Bijlsma, L.; Emke, E.; Hernández, F.; de Voogt, P.

    2013-01-01

    This work illustrates the potential of liquid chromatography coupled to a hybrid linear ion trap Fourier Transform Orbitrap mass spectrometer for the simultaneous identification and quantification of 24 drugs of abuse and relevant metabolites in sewage water. The developed methodology consisted of

  1. Matrix Assisted and/or Laser Desorption Ionization Quadrupole Ion Trap Time-of-Flight Mass Spectrometry of WO3 Clusters Formation in Gas Phase. Nanodiamonds, Fullerene, and Graphene Oxide Matrices

    Science.gov (United States)

    Ausekar, Mayuri Vilas; Mawale, Ravi Madhukar; Pazdera, Pavel; Havel, Josef

    2018-01-01

    The formation of W x O y +●/-● clusters in the gas phase was studied by laser desorption ionization (LDI) and matrix assisted laser desorption ionization (MALDI) of solid WO3. LDI produced (WO3) n + ●/- ● (n = 1-7) clusters. In MALDI, when using nano-diamonds (NDs), graphene oxide (GO), or fullerene (C60) matrices, higher mass clusters were generated. In addition to (WO3) n -● clusters, oxygen-rich or -deficient species were found in both LDI and MALDI (with the total number of clusters exceeding one hundred ≈ 137). This is the first time that such matrices have been used for the generation of(WO3) n +●/-● clusters in the gas phase, while new high mass clusters (WO3) n -● (n = 12-19) were also detected. [Figure not available: see fulltext.

  2. Matrix Assisted and/or Laser Desorption Ionization Quadrupole Ion Trap Time-of-Flight Mass Spectrometry of WO3 Clusters Formation in Gas Phase. Nanodiamonds, Fullerene, and Graphene Oxide Matrices

    Science.gov (United States)

    Ausekar, Mayuri Vilas; Mawale, Ravi Madhukar; Pazdera, Pavel; Havel, Josef

    2018-03-01

    The formation of W x O y +●/-● clusters in the gas phase was studied by laser desorption ionization (LDI) and matrix assisted laser desorption ionization (MALDI) of solid WO3. LDI produced (WO3) n + ●/- ● ( n = 1-7) clusters. In MALDI, when using nano-diamonds (NDs), graphene oxide (GO), or fullerene (C60) matrices, higher mass clusters were generated. In addition to (WO3) n -● clusters, oxygen-rich or -deficient species were found in both LDI and MALDI (with the total number of clusters exceeding one hundred ≈ 137). This is the first time that such matrices have been used for the generation of(WO3) n + ●/-● clusters in the gas phase, while new high mass clusters (WO3) n -● ( n = 12-19) were also detected. [Figure not available: see fulltext.

  3. A radio-frequency ion trap with string electrodes

    Science.gov (United States)

    Kanai, Daisuke; Hasegawa, Taro

    2018-02-01

    A radio-frequency (rf) ion trap with string electrodes is introduced. In this trap configuration, the rf electrodes are made of narrow metal strings, by which a negligibly small portion of light-induced fluorescence (LIF) is blocked. Then the LIF collection solid angle can be maximized. In the demonstration, barium ions are trapped and laser-cooled in the rf trap with string electrodes successfully, and the crystallization is confirmed by the LIF spectrum.

  4. Overview of the Livermore electron beam ion trap project

    International Nuclear Information System (INIS)

    Beiersdorfer, P.; Behar, E.; Boyce, K.R.; Brown, G.V.; Chen, H.; Gendreau, K.C.; Graf, A.; Gu, M.-F.; Harris, C.L.; Kahn, S.M.; Kelley, R.L.; Lepson, J.K.; May, M.J.; Neill, P.A.; Pinnington, E.H.; Porter, F.S.; Smith, A.J.; Stahle, C.K.; Szymkowiak, A.E.; Tillotson, A.; Thorn, D.B.; Traebert, E.; Wargelin, B.J.

    2003-01-01

    The Livermore electron beam ion trap facility has recently been moved to a new location within LLNL, and new instrumentation was added, including a 32-pixel microcalorimeter. The move was accompanied by a shift of focus toward in situ measurements of highly charged ions, which continue with increased vigor. Overviews of the facility, which includes EBIT-I and SuperEBIT, and the research projects are given, including results from optical spectroscopy, QED, and X-ray line excitation measurements

  5. A Linear Ion Trap with an Expanded Inscribed Diameter to Improve Optical Access for Fluorescence Spectroscopy

    Science.gov (United States)

    Rajagopal, Vaishnavi; Stokes, Chris; Ferzoco, Alessandra

    2017-08-01

    We report a custom-geometry linear ion trap designed for fluorescence spectroscopy of gas-phase ions at ambient to cryogenic temperatures. Laser-induced fluorescence from trapped ions is collected from between the trapping rods, orthogonal to the excitation laser that runs along the axis of the linear ion trap. To increase optical access to the ion cloud, the diameter of the round trapping rods is 80% of the inscribed diameter, rather than the roughly 110% used to approximate purely quadrupolar electric fields. To encompass as much of the ion cloud as possible, the first collection optic has a 25.4 mm diameter and a numerical aperture of 0.6. The choice of geometry and collection optics yields 107 detected photons/s from trapped rhodamine 6G ions. The trap is coupled to a closed-cycle helium refrigerator, which in combination with two 50 Ohm heaters enables temperature control to below 25 K on the rod electrodes. The purpose of the instrument is to broaden the applicability of fluorescence spectroscopy of gas-phase ions to cases where photon emission is a minority relaxation pathway. Such studies are important to understand how the microenvironment of a chromophore influences excited state charge transfer processes. [Figure not available: see fulltext.

  6. Qualitative Identification of Fentanyl Analogs and Other Opioids in Postmortem Cases by UHPLC-Ion Trap-MSn.

    Science.gov (United States)

    Shoff, Elisa N; Zaney, M Elizabeth; Kahl, Joseph H; Hime, George W; Boland, Diane M

    2017-07-01

    Since 2013, the Miami-Dade County Medical Examiner Department has experienced an increase in the number of opioid-related deaths. The majority of cases coincided with the introduction of fentanyl into the local heroin supply. From 2014 to 2015, Miami-Dade County experienced a near 600% increase in fentanyl-related deaths, followed by an additional 200% increase in 2016. In 2015, two novel fentanyl analogs were identified in medical examiner cases: beta-hydroxythiofentanyl and acetyl fentanyl. In 2016, four additional fentanyl analogs emerged: para-fluoroisobutyryl fentanyl, butyryl fentanyl, furanyl fentanyl and carfentanil, as well as the synthetic opioid U-47700. In order to address this epidemic, a method was developed and validated to identify 44 opioid-related and analgesic compounds in postmortem samples using ultra high performance liquid chromatography ion trap mass spectrometry with MSn capabilities. The limit of detection for all compounds ranged from 0.1 to 5 ng/mL, with a majority having MS3 spectral fragmentation. Blood, urine, liver or brain specimens from ~500 postmortem cases were submitted for analysis based on case history and/or initial screening results. Of those cases, 375 were positive for illicit fentanyl and/or one or more fentanyl analogs. Due to the potency of these compounds, they were almost always included in the cause of death. Worth emphasizing and extremely alarming is the detection of carfentanil in 134 cases, 104 of which were initially missed by gas chromatography mass spectrometry. By incorporating this sensitive, highly specific, and evolving screening procedure into the workflow, the toxicology laboratory continues to effectively assist the medical examiners in determining the cause and manner of death of decedents in Miami-Dade County. © The Author 2017. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  7. Chemometric profile of root extracts of Rhodiola imbricata Edgew. with hyphenated gas chromatography mass spectrometric technique.

    Directory of Open Access Journals (Sweden)

    Amol B Tayade

    Full Text Available Rhodiola imbricata Edgew. (Rose root or Arctic root or Golden root or Shrolo, belonging to the family Crassulaceae, is an important food crop and medicinal plant in the Indian trans-Himalayan cold desert. Chemometric profile of the n-hexane, chloroform, dichloroethane, ethyl acetate, methanol, and 60% ethanol root extracts of R. imbricata were performed by hyphenated gas chromatography mass spectrometry (GC/MS technique. GC/MS analysis was carried out using Thermo Finnigan PolarisQ Ion Trap GC/MS MS system comprising of an AS2000 liquid autosampler. Interpretation on mass spectrum of GC/MS was done using the NIST/EPA/NIH Mass Spectral Database, with NIST MS search program v.2.0g. Chemometric profile of root extracts revealed the presence of 63 phyto-chemotypes, among them, 1-pentacosanol; stigmast-5-en-3-ol, (3β,24S; 1-teracosanol; 1-henteracontanol; 17-pentatriacontene; 13-tetradecen-1-ol acetate; methyl tri-butyl ammonium chloride; bis(2-ethylhexyl phthalate; 7,8-dimethylbenzocyclooctene; ethyl linoleate; 3-methoxy-5-methylphenol; hexadecanoic acid; camphor; 1,3-dimethoxybenzene; thujone; 1,3-benzenediol, 5-pentadecyl; benzenemethanol, 3-hydroxy, 5-methoxy; cholest-4-ene-3,6-dione; dodecanoic acid, 3-hydroxy; octadecane, 1-chloro; ethanone, 1-(4-hydroxyphenyl; α-tocopherol; ascaridole; campesterol; 1-dotriacontane; heptadecane, 9-hexyl were found to be present in major amount. Eventually, in the present study we have found phytosterols, terpenoids, fatty acids, fatty acid esters, alkyl halides, phenols, alcohols, ethers, alkanes, and alkenes as the major group of phyto-chemotypes in the different root extracts of R. imbricata. All these compounds identified by GC/MS analysis were further investigated for their biological activities and it was found that they possess a diverse range of positive pharmacological actions. In future, isolation of individual phyto-chemotypes and subjecting them to biological activity will definitely prove fruitful

  8. Microbial metabolomics with gas chromatography/mass spectrometry

    NARCIS (Netherlands)

    Koek, M.M.; Muilwijk, B.; Werf, M.J. van der; Hankemeier, T.

    2006-01-01

    An analytical method was set up suitable for the analysis of microbial metabolomes, consisting of an oximation and silylation derivatization reaction and subsequent analysis by gas chromatography coupled to mass spectrometry. Microbial matrixes contain many compounds that potentially interfere with

  9. UV photodissociation action spectroscopy of haloanilinium ions in a linear quadrupole ion trap mass spectrometer.

    Science.gov (United States)

    Hansen, Christopher S; Kirk, Benjamin B; Blanksby, Stephen J; O'Hair, Richard A J; Trevitt, Adam J

    2013-06-01

    UV-vis photodissociation action spectroscopy is becoming increasingly prevalent because of advances in, and commercial availability of, ion trapping technologies and tunable laser sources. This study outlines in detail an instrumental arrangement, combining a commercial ion-trap mass spectrometer and tunable nanosecond pulsed laser source, for performing fully automated photodissociation action spectroscopy on gas-phase ions. The components of the instrumentation are outlined, including the optical and electronic interfacing, in addition to the control software for automating the experiment and performing online analysis of the spectra. To demonstrate the utility of this ensemble, the photodissociation action spectra of 4-chloroanilinium, 4-bromoanilinium, and 4-iodoanilinium cations are presented and discussed. Multiple photoproducts are detected in each case and the photoproduct yields are followed as a function of laser wavelength. It is shown that the wavelength-dependent partitioning of the halide loss, H loss, and NH3 loss channels can be broadly rationalized in terms of the relative carbon-halide bond dissociation energies and processes of energy redistribution. The photodissociation action spectrum of (phenyl)Ag2 (+) is compared with a literature spectrum as a further benchmark.

  10. Evaluation and prevention of the negative matrix effect of terpenoids on pesticides in apples quantification by gas chromatography-tandem mass spectrometry.

    Science.gov (United States)

    Giacinti, Géraldine; Raynaud, Christine; Capblancq, Sophie; Simon, Valérie

    2017-02-03

    The sample matrix can enhance the gas chromatography signal of pesticide residues relative to that obtained with the same concentration of pesticide in solvent. This paper is related to negative matrix effects observed in coupled gas chromatography-mass spectrometry ion trap (GC/MS 2 ) quantification of pesticides in concentrated extracts of apple peel prepared by the Quick Easy Cheap Effective Rugged and Safe (QuEChERS) method. It is focused on the pesticides most frequently used on the apple varieties studied, throughout the crop cycle, right up to harvest, to combat pests and diseases and to improve fruit storage properties. Extracts from the fleshy receptacle (flesh), the epiderm (peel) and fruit of three apple varieties were studied by high-performance thin-layer chromatography hyphenated with UV-vis light detection (HPTLC/UV visible). The peel extracts had high concentrations of triterpenic acids (oleanolic and ursolic acids), reaching 25mgkg -1 , whereas these compounds were not detected in the flesh extracts (negative matrix effects in GC/MS 2 . The differences in the behavior of pesticides with respect to matrix effects can be accounted for by the physicochemical characteristics of the molecules (lone pairs, labile hydrogen, conjugation). The HPTLC/UV visible method developed here for the characterization of QuEChERS extracts acts as a complementary clean-up method, aimed to decrease the negative matrix effects of such extracts. Copyright © 2016 Elsevier B.V. All rights reserved.

  11. Progress Report on the Improved Linear Ion Trap Physics Package

    Science.gov (United States)

    Prestage, John D.

    1995-01-01

    This article describes the first operational results from the extended linear ion trap frequency standard now being developed at JPL. This new design separates the state selection/interrogation region from the more critical microwave resonance region where the multiplied local oscillator (LO) signal is compared to the stable atomic transition. Hg+ ions have been trapped, shuttled back and forth between the resonance and state selection traps. In addition, microwave transitions between the Hg+ clock levels have been driven in the resonance trap and detected in the state selection trap.

  12. Note: Ion source design for ion trap systems

    Science.gov (United States)

    Noriega, J. R.; Quevedo, M.; Gnade, B.; Vasselli, J.

    2013-06-01

    A small plasma (glow discharge) based ion source and circuit are described in this work. The ion source works by producing a high voltage pulsed discharge between two electrodes in a pressure range of 50-100 mTorr. A third mesh electrode is used for ion extraction. The electrodes are small stainless steel screws mounted in a MACOR ionization chamber in a linear arrangement. The electrode arrangement is driven by a circuit, design for low power operation. This design is a proof of concept intended for applications on small cylindrical ion traps.

  13. Fast temperature programming in gas chromatography using resistive heating

    NARCIS (Netherlands)

    Dallüge, J.; Ou-Aissa, R.; Vreuls, J.J.; Brinkman, U.A.T.; Veraart, J.R.

    1999-01-01

    The features of a resistive-heated capillary column for fast temperature-programmed gas chromatography (GC) have been evaluated. Experiments were carried out using a commercial available EZ Flash GC, an assembly which can be used to upgrade existing gas chromatographs. The capillary column is placed

  14. Early stages in the history of gas chromatography.

    Science.gov (United States)

    Kolomnikov, Ivan G; Efremov, Alexander M; Tikhomirova, Tatyana I; Sorokina, Nadezhda M; Zolotov, Yury A

    2018-02-16

    The creation of gas chromatography is traditionally associated with the names of Nobel Prize winner Archer Martin and his colleagues Richard Synge and Anthony James. However, sometimes references to their predecessors can be found. An investigation conducted by the authors of this article not only confirmed the reliability of these references; but in fact led to the conclusion that by 1952, which is commonly believed to be the year when gas chromatography was born, many research papers had already been devoted to this method, mainly, in its gas-solid version. These papers are considered in this article. Copyright © 2018. Published by Elsevier B.V.

  15. Trapping ions from a fast beam in a radio-frequency ion trap: Exploring the energy exchange with the longitudinal radio-frequency field

    DEFF Research Database (Denmark)

    Svendsen, Annette; Lammich, Lutz; Vad Andersen, John Erik

    2013-01-01

    The possibility of injecting ions from an initially fast moving beam into a multipole radio-frequency (RF) ion trap without the use of buffer gas is described. The chosen trap geometry gives rise to an oscillating electric field along the direction of the incoming ions, and through an analytical...

  16. Ball-grid array architecture for microfabricated ion traps

    Science.gov (United States)

    Guise, Nicholas D.; Fallek, Spencer D.; Stevens, Kelly E.; Brown, K. R.; Volin, Curtis; Harter, Alexa W.; Amini, Jason M.; Higashi, Robert E.; Lu, Son Thai; Chanhvongsak, Helen M.; Nguyen, Thi A.; Marcus, Matthew S.; Ohnstein, Thomas R.; Youngner, Daniel W.

    2015-05-01

    State-of-the-art microfabricated ion traps for quantum information research are approaching nearly one hundred control electrodes. We report here on the development and testing of a new architecture for microfabricated ion traps, built around ball-grid array (BGA) connections, that is suitable for increasingly complex trap designs. In the BGA trap, through-substrate vias bring electrical signals from the back side of the trap die to the surface trap structure on the top side. Gold-ball bump bonds connect the back side of the trap die to an interposer for signal routing from the carrier. Trench capacitors fabricated into the trap die replace area-intensive surface or edge capacitors. Wirebonds in the BGA architecture are moved to the interposer. These last two features allow the trap die to be reduced to only the area required to produce trapping fields. The smaller trap dimensions allow tight focusing of an addressing laser beam for fast single-qubit rotations. Performance of the BGA trap as characterized with 40Ca+ ions is comparable to previous surface-electrode traps in terms of ion heating rate, mode frequency stability, and storage lifetime. We demonstrate two-qubit entanglement operations with 171Yb+ ions in a second BGA trap.

  17. Ball-grid array architecture for microfabricated ion traps

    International Nuclear Information System (INIS)

    Guise, Nicholas D.; Fallek, Spencer D.; Stevens, Kelly E.; Brown, K. R.; Volin, Curtis; Harter, Alexa W.; Amini, Jason M.; Higashi, Robert E.; Lu, Son Thai; Chanhvongsak, Helen M.; Nguyen, Thi A.; Marcus, Matthew S.; Ohnstein, Thomas R.; Youngner, Daniel W.

    2015-01-01

    State-of-the-art microfabricated ion traps for quantum information research are approaching nearly one hundred control electrodes. We report here on the development and testing of a new architecture for microfabricated ion traps, built around ball-grid array (BGA) connections, that is suitable for increasingly complex trap designs. In the BGA trap, through-substrate vias bring electrical signals from the back side of the trap die to the surface trap structure on the top side. Gold-ball bump bonds connect the back side of the trap die to an interposer for signal routing from the carrier. Trench capacitors fabricated into the trap die replace area-intensive surface or edge capacitors. Wirebonds in the BGA architecture are moved to the interposer. These last two features allow the trap die to be reduced to only the area required to produce trapping fields. The smaller trap dimensions allow tight focusing of an addressing laser beam for fast single-qubit rotations. Performance of the BGA trap as characterized with 40 Ca + ions is comparable to previous surface-electrode traps in terms of ion heating rate, mode frequency stability, and storage lifetime. We demonstrate two-qubit entanglement operations with 171 Yb + ions in a second BGA trap

  18. Characterization of the chemical composition of white chrysanthemum flowers of Hangzhou by using high-performance ion trap mass spectrometry.

    Science.gov (United States)

    Zhou, Xiahui; Chen, Xiaocheng; Wu, Xin; Cao, Gang; Zhang, Junjie

    2016-04-01

    In this study, high-performance liquid chromatography coupled with amaZon SL high-performance ion trap mass spectrometry was used to analyze the target components in white chrysanthemum flowers of Hangzhou. Twenty-one components were detected and identified in both white chrysanthemum flowers of Hangzhou samples by using target compound analysis. Furthermore, seven new compounds in white chrysanthemum flowers of Hangzhou were found and identified by analyzing the fragment ion behavior in the mass spectra. The established method can be expedient for the global quality investigation of complex components in herbal medicines and food. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  19. MOMA and other next-generation ion trap mass spectrometers for planetary exploration

    Science.gov (United States)

    Arevalo, R. D., Jr.; Brinckerhoff, W. B.; Getty, S.; Mahaffy, P. R.; van Amerom, F. H. W.; Danell, R.; Pinnick, V. T.; Li, X.; Grubisic, A.; Southard, A. E.; Hovmand, L.; Cottin, H.; Makarov, A.

    2016-12-01

    Since the 1970's, quadrupole mass spectrometer (QMS) systems have served as low-risk, cost-efficient means to explore the inner and outer reaches of the solar system. These legacy instruments have interrogated the compositions of the lunar exosphere (LADEE), surface materials on Mars (MSL), and the atmospheres of Venus (Pioneer Venus), Mars (MAVEN) and outer planets (Galileo and Cassini-Huygens). However, the in situ detection of organic compounds on Mars and Titan, coupled with ground-based measurements of amino acids in meteorites and a variety of organics in comets, has underlined the importance of molecular disambiguation in the characterization of high-priority planetary environments. The Mars Organic Molecule Analyzer (MOMA) flight instrument, centered on a linear ion trap, enables the in situ detection of volatile and non-volatile organics, but also the characterization of molecular structures through SWIFT ion isolation/excitation and tandem mass spectrometry (MSn). Like the SAM instrument on MSL, the MOMA investigation also includes a gas chromatograph (GC), thereby enabling the chemical separation of potential isobaric interferences based on retention times. The Linear Ion Trap Mass Spectrometer (LITMS; PI: William Brinckerhoff), developed to TRL 6 via the ROSES MatISSE Program, augments the core MOMA design and adds: expanded mass range (from 20 - 2000 Da); high-temperature evolved gas analysis (up to 1300°C); and, dual polarity detector assemblies (supporting the measurement of negative ions). The LITMS instrument will be tested in the field in 2017 through the Atacama Rover Astrobiology Drilling Studies (ARADS; PI: Brian Glass) ROSES PSTAR award. Following on these advancements, the Advanced Resolution Organic Molecule Analyzer (AROMA; PI: Ricardo Arevalo Jr.), supported through the ROSES PICASSO Program, combines a highly capable MOMA/LITMS-like linear ion trap and the ultrahigh resolution CosmOrbitrap mass analyzer developed by a consortium of five

  20. Chromatography

    Science.gov (United States)

    ... that are bonded together. For example, water is a chemical bond of oxygen and hydrogen. Proteins are another type of chemical compound. There are different kinds of chromatography. These include gas, high pressure liquid, or ion ...

  1. Gas chromatography/matrix-isolation apparatus

    Science.gov (United States)

    Reedy, Gerald T.

    1986-01-01

    A gas-sample collection device provides matrix isolation of individual gas bands from a gas chromatographic separation and for the spectroscopic analysis of the individual sample bands. The device includes a vacuum chamber containing a rotatably supported, specular carousel having at least one reflecting surface for holding a sample deposited thereon. A gas inlet is provided for depositing a mixture of sample and matrix material on the reflecting surface which is maintained at a sufficiently low temperature to cause solidification. A first parabolic mirror directs an incident beam of electromagnetic radiation, such as in the infrared (IR) spectrum, from a source onto the sample/matrix mixture while a second parabolic mirror directs a second beam of electromagnetic radiation reflected by the specular surface to an IR spectrometer for determining the absorption spectra of the sample material deposited on the reflecting surface. The pair of off-axis parabolic mirrors having a common focal point are positioned outside of the vacuum chamber and may be displaced in combination for improved beam positioning and alignment. The carousel is provided with an aperture for each reflecting surface to facilitate accurate positioning of the incident beam relative to the gas-samples under analysis. Improved gas-sample deposition is insured by the use of a long focal length stereomicroscope positioned outside of the vacuum chamber for monitoring sample formation through a window, while the sample collector is positioned outside of the zone bounded by the incident and reflected electromagnetic beams for improved sample access and monitoring.

  2. The non-neutral ion trap at Brigham Young University

    Science.gov (United States)

    Peterson, Bryan; Williams, Chad; Hall, William; Hart, Grant

    2011-10-01

    We have constructed a non-neutral ion trap with the eventual goal of measuring the rate of decay of singly-ionized 7Be. Since 7Be decays exclusively by electron capture a Malmberg-Penning trap provides an ideal environment for this measurement due to the near absence of free electrons. We will use the FTICR (Fourier Transform Ion Cyclotron Resonance) mass spectrometry technique to measure the ratio of 7Be to 7Li to determine the decay rate. We are using an enriched boron carbide target (77.7% 10B, 2.3% 11B, 20% 12C) to provide the ions for the test plasma. This allows us to test the FTICR technique through the presence of three different ions at very different concentrations. We will discuss the current status of the experiment.

  3. Low power RF amplifier circuit for ion trap applications

    Science.gov (United States)

    Noriega, J. R.; García-Delgado, L. A.; Gómez-Fuentes, R.; García-Juárez, A.

    2016-09-01

    A low power RF amplifier circuit for ion trap applications is presented and described. The amplifier is based on a class-D half-bridge amplifier with a voltage mirror driver. The RF amplifier is composed of an RF class-D amplifier, an envelope modulator to ramp up the RF voltage during the ion analysis stage, a detector or amplitude demodulation circuit for sensing the output signal amplitude, and a feedback amplifier that linearizes the steady state output of the amplifier. The RF frequency is set by a crystal oscillator and the series resonant circuit is tuned to the oscillator frequency. The resonant circuit components have been chosen, in this case, to operate at 1 MHz. In testings, the class-D stage operated at a maximum of 78 mW at 1.1356 MHz producing 225 V peak.

  4. Gas chromatography/matrix-isolation apparatus

    Science.gov (United States)

    Reedy, G.T.

    1986-06-10

    A gas-sample collection device provides matrix isolation of individual gas bands from a gas chromatographic separation and for the spectroscopic analysis of the individual sample bands. The device includes a vacuum chamber containing a rotatably supported, specular carousel having at least one reflecting surface for holding a sample deposited thereon. A gas inlet is provided for depositing a mixture of sample and matrix material on the reflecting surface which is maintained at a sufficiently low temperature to cause solidification. A first parabolic mirror directs an incident beam of electromagnetic radiation, such as in the infrared (IR) spectrum, from a source onto the sample/matrix mixture while a second parabolic mirror directs a second beam of electromagnetic radiation reflected by the specular surface to an IR spectrometer for determining the absorption spectra of the sample material deposited on the reflecting surface. The pair of off-axis parabolic mirrors having a common focal point are positioned outside of the vacuum chamber and may be displaced in combination for improved beam positioning and alignment. The carousel is provided with an aperture for each reflecting surface to facilitate accurate positioning of the incident beam relative to the gas-samples under analysis. Improved gas-sample deposition is insured by the use of a long focal length stereomicroscope positioned outside of the vacuum chamber for monitoring sample formation through a window, while the sample collector is positioned outside of the zone bounded by the incident and reflected electromagnetic beams for improved sample access and monitoring. 10 figs.

  5. Analysis of sulphur compounds in underground reservoirs of natural gas and town gas by gas chromatography and mass spectrometry

    Energy Technology Data Exchange (ETDEWEB)

    Triska, J.; Kuras, M.; Zachar, P.; Vodicka, L. (Institute of Chemical Technology, Prague (Czechoslovakia). Lab. of Synthetic Fuels)

    1990-09-01

    This paper deals with mass spectrometry and gas chromatography of the sulphur compounds in waste waters from the natural gas underground reservoirs, in extracts of activated charcoal used for purification of town gas, and in the oils from compressors of natural gas. (orig.).

  6. High resolution gas chromatography in dedicated petrochemical and environmental analysis

    International Nuclear Information System (INIS)

    Nijs, R. De

    1990-01-01

    Turn key systems dedicated and designed for a special application in petrochemical as well as environmental analysis are used already for many years. However, the use of high resolution gas chromatography columns in this type of equipment is only performed recently. In petrochemistry, examples of this type of systems are analyzers for light hydrocarbons, inerts and oxygenates in petrochemical streams and natural gas. In environmental monitoring analyzers for hydrocarbons and halogenated hydrocarbons in air or waste water and surface water are of importance. The use of capillary gas chromatography columns in this kind of application is resulting, when compared with packed columns, in improved separation power, a higher speed of analysis and in most cases a lower detection limit. Because of the high separation power of capillary columns, when compared with packed columns, the amount of columns needed to obtain a certain separation is less and so the analysis is simplified, becoming more reliable. For environmental analysis the use of high resolution columns in combination with thermal desorption could trap techniques in the analysis of volatile organic compound (VOC) in air results in information on ppb or even ppt level pollution of hydrocarbon and halogenated hydrocarbons. For the analysis of VOC's in water purge and trap techniques are used in combination with high resolution gas chromatography. Applications and results obtained with above mentioned equipment will be discussed. Special attention will be given to the incorporation of high resolution chromatography in this type of equipment

  7. Analysis of essential oils by gas chromatography and mass spectrometry

    Energy Technology Data Exchange (ETDEWEB)

    Masada, Y.

    1976-01-01

    The book is in two parts: first part Essential Oil includes compositae; labiatae; verbenaceae; oleaceae; umbelliferae; myrtaceae; euphorbiaceae; rutaceae; geraniaceae; rosaceae; lauraceae; myristicaceae; anonaceae; santalaceae; moraceae; piperaceae; zingiberaceae; araceae; gramineae; and cupressaceae written in English and Japanese. Part two includes essential oil; gas chromatography, and mass spectrometry written in Japanese. (DP)

  8. Enthalpy of Vaporization by Gas Chromatography: A Physical Chemistry Experiment

    Science.gov (United States)

    Ellison, Herbert R.

    2005-01-01

    An experiment is conducted to measure the enthalpy of vaporization of volatile compounds like methylene chloride, carbon tetrachloride, and others by using gas chromatography. This physical property was measured using a very tiny quantity of sample revealing that it is possible to measure the enthalpies of two or more compounds at the same time.

  9. Gas chromatography mass spectrometry : key technology in metabolomics

    NARCIS (Netherlands)

    Koek, Maud Marijtje

    2009-01-01

    Metabolomics involves the unbiased quantitative and qualitative analysis of the complete set of metabolites present in cells, body fluids and tissues. Gas chromatography coupled to mass spectrometry (GC-MS) is very suitable for metabolomics analysis, as it combines high separation power with

  10. Gas Chromatography Mass Spectrometry of Quassia undulata Seed ...

    African Journals Online (AJOL)

    Prof. Ogunji

    Key words: Quassia undulata, GC MS, Biodiesel, Gbur, seed oil, Gas Chromatography, Mass. Spectrometry. Correspondence: waneniko@yahoo.co.uk ... these triglycerides and their applications depend on the fatty acid constituents .... injector temperature of 250°C and ion source temperature of 200°C and a split ratio of ...

  11. Gas Chromatography-Mass Spectrometric Analysis of Nematicidal ...

    African Journals Online (AJOL)

    chromatography (GC) and gas chromaotography-mass spectrometry (GC-MS). The nematicidal activity of the essential oil and its major constituents was determined against second stage juveniles of H. avenae. Results: A total of 33 components of the essential oil were identified. The major constituents were bornyl acetate ...

  12. An application of gas chromatography to planetary atmospheres

    Science.gov (United States)

    Oyama, V.

    1974-01-01

    A gas chromatography developed for the Viking experiment is described. The instrument is designed to measure gases in planetary atmospheres and head space in a chamber. It is hoped that the chromatograph will also measure any biological activity present in these environments.

  13. Specialized Gas Chromatography--Mass Spectrometry Systems for Clinical Chemistry.

    Science.gov (United States)

    Gochman, Nathan; And Others

    1979-01-01

    A discussion of the basic design and characteristics of gas chromatography-mass spectrometry systems used in clinical chemistry. A comparison of three specific systems: the Vitek Olfax IIA, Hewlett-Packard HP5992, and Du Pont DP-102 are included. (BB)

  14. Development of a thermal desorption modulator for gas chromatography

    NARCIS (Netherlands)

    Geus, H.J.; Boer, de J.; Brinkman, U.A.Th.

    1997-01-01

    The separation space in gas chromatography can be enhanced dramatically by the comprehensive coupling of two independent separation dimensions. An interface between the two columns must accumulate analytes eluting from the first dimension, focus them and at the appropriate moment transfer them to

  15. Determination of Collision Cross Sections Using a Fourier Transform Electrostatic Linear Ion Trap Mass Spectrometer.

    Science.gov (United States)

    Dziekonski, Eric T; Johnson, Joshua T; Lee, Kenneth W; McLuckey, Scott A

    2018-02-01

    Collision cross sections (CCSs) were determined from the frequency-domain linewidths in a Fourier transform electrostatic linear ion trap. With use of an ultrahigh-vacuum precision leak valve and nitrogen gas, transients were recorded as the background pressure in the mass analyzer chamber was varied between 4× 10 -8 and 7 × 10 -7 Torr. The energetic hard-sphere ion-neutral collision model, described by Xu and coworkers, was used to relate the recorded image charge to the CCS of the molecule. In lieu of our monoisotopically isolating the mass of interest, the known relative isotopic abundances were programmed into the Lorentzian fitting algorithm such that the linewidth was extracted from a sum of Lorentzians. Although this works only if the isotopic distribution is known a priori, it prevents ion loss, preserves the high signal-to-noise ratio, and minimizes the experimental error on our homebuilt instrument. Six tetraalkylammonium cations were used to correlate the CCS measured in the electrostatic linear ion trap with that measured by drift-tube ion mobility spectrometry, for which there was an excellent correlation (R 2 ≈ 0.9999). Although the absolute CCSs derived with our method differ from those reported, the extracted linear correlation can be used to correct the raw CCS. With use of [angiotensin II] 2+ and reserpine, the corrected CCSs (334.9 ± 2.1 and 250.1 ± 0.5, respectively) were in good agreement with the reported ion mobility spectrometry CCSs (335 and 254.3, respectively). With sufficient signal-to-noise ratio, the CCSs determined are reproducible to within a fraction of a percent, comparable to the uncertainties reported on dedicated ion mobility instruments. Graphical Abstract ᅟ.

  16. Determination of Collision Cross Sections Using a Fourier Transform Electrostatic Linear Ion Trap Mass Spectrometer

    Science.gov (United States)

    Dziekonski, Eric T.; Johnson, Joshua T.; Lee, Kenneth W.; McLuckey, Scott A.

    2018-02-01

    Collision cross sections (CCSs) were determined from the frequency-domain linewidths in a Fourier transform electrostatic linear ion trap. With use of an ultrahigh-vacuum precision leak valve and nitrogen gas, transients were recorded as the background pressure in the mass analyzer chamber was varied between 4× 10-8 and 7 × 10-7 Torr. The energetic hard-sphere ion-neutral collision model, described by Xu and coworkers, was used to relate the recorded image charge to the CCS of the molecule. In lieu of our monoisotopically isolating the mass of interest, the known relative isotopic abundances were programmed into the Lorentzian fitting algorithm such that the linewidth was extracted from a sum of Lorentzians. Although this works only if the isotopic distribution is known a priori, it prevents ion loss, preserves the high signal-to-noise ratio, and minimizes the experimental error on our homebuilt instrument. Six tetraalkylammonium cations were used to correlate the CCS measured in the electrostatic linear ion trap with that measured by drift-tube ion mobility spectrometry, for which there was an excellent correlation ( R 2 ≈ 0.9999). Although the absolute CCSs derived with our method differ from those reported, the extracted linear correlation can be used to correct the raw CCS. With use of [angiotensin II]2+ and reserpine, the corrected CCSs (334.9 ± 2.1 and 250.1 ± 0.5, respectively) were in good agreement with the reported ion mobility spectrometry CCSs (335 and 254.3, respectively). With sufficient signal-to-noise ratio, the CCSs determined are reproducible to within a fraction of a percent, comparable to the uncertainties reported on dedicated ion mobility instruments.

  17. Detection of Griseofulvin and Dechlorogriseofulvin by Thin-Layer Chromatography and Gas-Liquid Chromatography

    Science.gov (United States)

    Cole, R. J.; Kirksey, J. W.; Holaday, C. E.

    1970-01-01

    A rapid and accurate method is described for the determination of griseofulvin and dechlorogriseofulvin extracted from Penicillium urticae with chloroform. Thinlayer chromatography was used to tentatively identify griseofulvin or dechlorogriseofulvin, or both. Two gas-liquid chromatographic systems provided additional qualitative information and simultaneous quantitation of the individual compounds. PMID:5415206

  18. Gas chromatography-vacuum ultraviolet spectroscopy for multiclass pesticide identification.

    Science.gov (United States)

    Fan, Hui; Smuts, Jonathan; Walsh, Phillip; Harrison, Dale; Schug, Kevin A

    2015-04-10

    A new vacuum ultraviolet detector for gas chromatography was recently developed and applied to multiclass pesticide identification. VUV detection features full spectral acquisition in a wavelength range of 115-240nm, where virtually all chemical species absorb. VUV absorption spectra of 37 pesticides across different classes were recorded. These pesticides display rich gas phase absorption features across various classes. Even for isomeric compounds, such as hexachlorocyclohexane (HCH) isomers, the VUV absorption spectra are unique and can be easily differentiated. Also demonstrated is the ability to use VUV data analysis software for deconvolution of co-eluting signals. As a universal detector, VUV provides both qualitative and quantitative information. It offers high specificity, sensitivity (pg on-column detection limits), and a fast data acquisition rate, making it a powerful tool for multiclass pesticide screening when combined with gas chromatography. Copyright © 2015 Elsevier B.V. All rights reserved.

  19. Ion Motion Stability in Asymmetric Surface Electrode Ion Traps

    Science.gov (United States)

    Shaikh, Fayaz; Ozakin, Arkadas

    2010-03-01

    Many recently developed designs of the surface electrode ion traps for quantum information processing have asymmetry built into their geometries. The asymmetry helps rotate the trap axes to angles with respect to electrode surface that facilitate laser cooling of ions but introduces a relative angle between the RF and DC fields and invalidates the classical stability analysis of the symmetric case for which the equations of motion are decoupled. For asymmetric case the classical motion of a single ion is given by a coupled, multi-dimensional version of Mathieu's equation. In this poster we discuss the stability diagram of asymmetric surface traps by performing an approximate multiple scale perturbation analysis of the coupled Mathieu equations, and validate the results with numerical simulations. After obtaining the stability diagram for the linear fields, we simulate the motion of an ion in a given asymmetric surface trap, utilizing a method-of-moments calculation of the electrode fields. We obtain the stability diagram and compare it with the ideal case to find the region of validity. Finally, we compare the results of our stability analysis to experiments conducted on a microfabricated asymmetric surface trap.

  20. Upgrade of the electron beam ion trap in Shanghai

    Energy Technology Data Exchange (ETDEWEB)

    Lu, D.; Yang, Y.; Xiao, J.; Shen, Y.; Fu, Y.; Wei, B.; Yao, K.; Hutton, R.; Zou, Y., E-mail: zouym@fudan.edu.cn [The Key Lab of Applied Ion Beam Physics, Ministry of Education, 200433 Shanghai (China); Shanghai EBIT Lab, Institute of Modern Physics, Fudan University, 200433 Shanghai (China)

    2014-09-15

    Over the last few years the Shanghai electron beam ion trap (EBIT) has been successfully redesigned and rebuilt. The original machine, developed under collaboration with the Shanghai Institute of Applied Physics, first produced an electron beam in 2005. It could be tuned with electron energies between 1 and 130 keV and beam current up to 160 mA. After several years of operation, it was found that several modifications for improvements were necessary to reach the goals of better electron optics, higher photon detection, and ion injection efficiencies, and more economical running costs. The upgraded Shanghai-EBIT is made almost entirely from Ti instead of stainless steel and achieves a vacuum of less than 10{sup −10} Torr, which helps to minimize the loss of highly changed ions through charge exchange. Meanwhile, a more compact structure and efficient cryogenic system, and excellent optical alignment have been of satisfactory. The magnetic field in the central trap region can reach up till 4.8 T with a uniformity of 2.77 × 10{sup −4}. So far the upgraded Shanghai-EBIT has been operated up to an electron energy of 151 keV and a beam current of up to 218 mA, although promotion to even higher energy is still in progress. Radiation from ions as highly charged as Xe{sup 53+,} {sup 54+} has been produced and the characterization of current density is estimated from the measured electron beam width.

  1. 21 CFR 862.2250 - Gas liquid chromatography system for clinical use.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Gas liquid chromatography system for clinical use... Instruments § 862.2250 Gas liquid chromatography system for clinical use. (a) Identification. A gas liquid chromatography system for clinical use is a device intended to separate one or more drugs or compounds from a...

  2. Application of gas chromatography to the investigations on polypropylene radiolysis

    International Nuclear Information System (INIS)

    Zagorski, Z.P.; Gluszewski, W.

    2006-01-01

    Refinement of the gas chromatography (GC) instrumental approach permitted not only improvement of investigation in basic research, but also development of a new kind of polypropylene blends, more suitable for the production of medical devices and radiation sterilization. It has been shown, that using the GC method not only methane and carbon dioxide can be measured, but also the consumption of oxygen which reacts with free radicals on the polypropylene chain

  3. Establishment of analysis method for methane detection by gas chromatography

    Science.gov (United States)

    Liu, Xinyuan; Yang, Jie; Ye, Tianyi; Han, Zeyu

    2018-02-01

    The study focused on the establishment of analysis method for methane determination by gas chromatography. Methane was detected by hydrogen flame ionization detector, and the quantitative relationship was determined by working curve of y=2041.2x+2187 with correlation coefficient of 0.9979. The relative standard deviation of 2.60-6.33% and the recovery rate of 96.36%∼105.89% were obtained during the parallel determination of standard gas. This method was not quite suitable for biogas content analysis because methane content in biogas would be over the measurement range in this method.

  4. Chelate-modified polymers for atmospheric gas chromatography

    Science.gov (United States)

    Christensen, W. W.; Mayer, L. A.; Woeller, F. H. (Inventor)

    1980-01-01

    Chromatographic materials were developed to serve as the stationary phase of columns used in the separation of atmospheric gases. These materials consist of a crosslinked porous polymer matrix, e.g., a divinylbenzene polymer, into which has been embedded an inorganic complexed ion such as N,N'-ethylene-bis-(acetylacetoniminato)-cobalt (2). Organic nitrogenous bases, such as pyridine, may be incorporated into the chelate polymer complexes to increase their chromatographic utility. With such materials, the process of gas chromatography is greatly simplified, especially in terms of time and quantity of material needed for a gas separation.

  5. Ultraviolet degradation of procymidone -structuralcharacterization by gas chromatography coupled with masss spectrometry and potential toxicity of photoproducts using in silico tests

    International Nuclear Information System (INIS)

    Rifai, A.; Jaber, F.; Souissi, Y.; Genty, Ch.; Bourcier, S.; Bouchonnet, S.; Clavaguera, C.

    2013-01-01

    RATIONALE: Procymidone is a dicarboximide fungicide mainly used for vineyard protection but also for different crops. The structural elucidation of by-products arising from the UV-visible photodegradation of procymidone has been investigated by gas chromatography coupled with mass spectrometry. The potential toxicities of photoproducts were estimated by in silico tests. METHODS: Aqueous solutions of procymidone were irradiated for up to 90 min in a self-made reactor equipped with a mercury lamp. Analyses were carried out on a gas chromatograph coupled with an ion trap mass spectrometer operated in electron ionization and methanol positive chemical ionization. Multistage collision-induced dissociation (CID) experiments were performed to establish dissociation pathways of ions. Toxicities of byproducts were estimated using the QSAR T.E.S.T. program. RESULTS: Sixteen photoproducts were investigated. Chemical structures were proposed mainly based on the interpretation of multistage CID experiments, but also on their relative retention times and kinetics data. These structures enabled photodegradation pathways to be suggested. Only three photoproducts remain present after 90 min of irradiation. Among them, 3,5-dichloroaniline presents a predicted rat LD50 toxicity about ten times greater than that of procymidone. CONCLUSIONS: 3,5-Dichloroaniline is the only photoproduct reported in previous articles. Eight by-products among the sixteen characterized might be as toxic, if not more, than procymidone itself considering the QSAR-predicted rat LD 50. (author)

  6. Comparison of direct sampling ion trap mass spectrometry to GC/MS for monitoring VOCs in groundwater

    International Nuclear Information System (INIS)

    Wise, M.B.; Merriweather, R.; Guerin, M.; Thompson, C.V.

    1995-01-01

    Rapid analytical methods which utilize Direct Sampling Ion Trap Mass Spectrometry for field screening and compliance monitoring of volatile organic compounds in groundwater have been under development in this laboratory for several years. These methods can be used on fieldable instrumentation, have low ppb detection limits, and require little or no sample preparation. The DSITMS analysis of VOCs in water uses a three minute direct purge of the water sample with a stream of helium at a flow rate of 100 mL/min. VOCs partition into the helium stream and are carried directly into the ion trap via a 100 um section of fused silica capillary. Most of the sample is vented through an open/split interface, with only about 1 mL/min. entering the mass spectrometer. Analysis of the VOCs is accomplished by alternating conditions in the ion trap at roughly one second intervals between electron ionization and chemical ionization (water reagent gas). Two such methods for the analysis of VOCs in water have been submitted to EPA for regulatory approval, and in order to facilitate this process, validation studies have been conducted comparing the DSITMS method to a standard method such as purge-and-trap GC/MS. One such study, recently completed, involved the analysis of over 100 groundwater samples collected from the Oak Ridge reservation for compliance monitoring. Split samples of the groundwater were analyzed by DSITMS and by purge-and-trap GC/MS at a local CLP laboratory. The results of the comparative study generally show excellent qualitative and quantitative agreement between the DSITMS and standard methods, with the DSITMS method being superior with respect to speed, cost, ease of use, and minimized artifacts

  7. Study of radiolysis products of natural organic materials by means of gas chromatography

    International Nuclear Information System (INIS)

    Pogocki, D.

    1994-01-01

    Analytical methods based on gas chromatography for identification determination of products arising during food irradiation have been presented. Behind the classics version of the methods one has shown also combined methods being the on-line connection of gas chromatography with mass spectroscopy as well as gas chromatography with liquid chromatography and mass spectroscopy. The applicability as well as weakness and advantages of each version have been discussed on the context of food irradiation. 11 refs, 7 figs

  8. Fast analysis of phthalates in freeze-dried baby foods by ultrasound-vortex-assisted liquid-liquid microextraction coupled with gas chromatography-ion trap/mass spectrometry.

    Science.gov (United States)

    Russo, Mario Vincenzo; Avino, Pasquale; Notardonato, Ivan

    2016-11-25

    This paper is focused on the determination of phthalates (PAEs), compounds "plausibly" endocrine disruptors, in baby food products by means of a method based on ultrasound-vortex-assisted liquid-liquid microextraction coupled with GC-IT/MS (UVALLME-GC-IT/MS). Particularly, the whole procedure allows the determination of six phthalates such as DMP, DEP, DBP, iBcEP, BBP and DEHP. After dissolution of 0.1g product sample and addition of anthracene as Internal Standard, 250μL of n-heptane are used as extraction solvent. The solution, held for 5min on the vortex mixer and for 6min in an ultrasonic bath at 100W for favoring the solvent dispersion and consequently the analyte extraction, is centrifuged at 4000rpm for 30min. About 100μL of heptane are recovered and 1μL is injected into the GC-IT/MS. All the analytical parameters investigated are deeply discussed: under the best conditions, the percentage recoveries range between 96.2 and 109.2% with an RSD ≤10.5% whereas the Limit of Detections (LODs) and the Limit of Quantifications (LOQs) are below 11 and 20ngg -1 , respectively, for all the PAEs except for iBcEP (23 and 43ngg -1 , respectively). The linear dynamic range of this procedure is between 10 and 5000ngg -1 with R 2 ≥0.92. The method has been applied to real commercial freeze-dried samples (chicken and turkey meats) available on the Italian pharmaceutical market: three PAEs were preliminary identified, i.e. DEP (14ngg -1 ), DBP (11ngg -1 ) and DEHP (64ngg -1 ). Copyright © 2016. Published by Elsevier B.V.

  9. Comparison of ultra high performance supercritical fluid chromatography, ultra high performance liquid chromatography, and gas chromatography for the separation of synthetic cathinones.

    Science.gov (United States)

    Carnes, Stephanie; O'Brien, Stacey; Szewczak, Angelica; Tremeau-Cayel, Lauriane; Rowe, Walter F; McCord, Bruce; Lurie, Ira S

    2017-09-01

    A comparison of ultra high performance supercritical fluid chromatography, ultra high performance liquid chromatography, and gas chromatography for the separation of synthetic cathinones has been conducted. Nine different mixtures of bath salts were analyzed in this study. The three different chromatographic techniques were examined using a general set of controlled synthetic cathinones as well as a variety of other synthetic cathinones that exist as positional isomers. Overall 35 different synthetic cathinones were analyzed. A variety of column types and chromatographic modes were examined for developing each separation. For the ultra high performance supercritical fluid chromatography separations, analyses were performed using a series of Torus and Trefoil columns with either ammonium formate or ammonium hydroxide as additives, and methanol, ethanol or isopropanol organic solvents as modifiers. Ultra high performance liquid chromatographic separations were performed in both reversed phase and hydrophilic interaction chromatographic modes using SPP C18 and SPP HILIC columns. Gas chromatography separations were performed using an Elite-5MS capillary column. The orthogonality of ultra high performance supercritical fluid chromatography, ultra high performance liquid chromatography, and gas chromatography was examined using principal component analysis. For the best overall separation of synthetic cathinones, the use of ultra high performance supercritical fluid chromatography in combination with gas chromatography is recommended. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  10. Investigation of borneols sold in Taiwan by chiral gas chromatography

    Directory of Open Access Journals (Sweden)

    Tsung-Jung Ho

    2018-01-01

    Full Text Available Borneol is a monoterpene that is widely used in traditional Chinese medicine. There are two different products sold in Taipei's traditional Chinese medicine market, natural and chemically synthesized borneol. Chemically synthesized borneol contains four stereoisomers, (+-isoborneol, (−-isoborneol, (−-borneol, and (+-borneol. The ratio of these four isomers in chemically synthesized and natural borneol products was determined by gas chromatography mass spectrometry. A huge variation between these products is highlighted in this survey. The results suggest that the Food and Drug Administrations in Asian countries should establish a regulatory standard regarding the ratio of the four different borneol isomers in both natural and chemically synthesized borneol.

  11. Analysis of artificial fireplace logs by high temperature gas chromatography.

    Science.gov (United States)

    Kuk, Raymond J

    2002-11-01

    High temperature gas chromatography is used to analyze the wax of artificial fireplace logs (firelogs). Firelogs from several different manufacturers are studied and compared. This study shows that the wax within a single firelog is homogeneous and that the wax is also uniform throughout a multi-firelog package. Different brands are shown to have different wax compositions. Firelogs of the same brand, but purchased in different locations, also have different wax compositions. With this information it may be possible to associate an unknown firelog sample to a known sample, but a definitive statement of the origin cannot be made.

  12. [Determination of acetochlor and oxyfluorfen by capillary gas chromatography].

    Science.gov (United States)

    Xiang, Wen-Sheng; Wang, Xiang-Jing; Wang, Jing; Wang, Qing

    2002-09-01

    A method is described for the determination of acetochlor and oxyfluorfen by capillary gas chromatography with FID and an SE-30 capillary column (60 m x 0.53 mm i. d., 1.5 microm), using dibutyl phthalate as the internal standard. The standard deviations for acetochlor and oxyfluorfen concentration(mass fraction) were 0.44% and 0.47% respectively. The relative standard deviations for acetochlor and oxyfluorfen were 0.79% and 0.88% and the average recoveries for acetochlor and oxyfluorfen were 99.3% and 101.1% respectively. The method is simple, rapid and accurate.

  13. Diesel characterization by high-resolution mass spectrometry - gas chromatography

    International Nuclear Information System (INIS)

    Baldrich, C.A

    1998-01-01

    High-resolution mass spectrometry-gas chromatography is combined with the HC22 method in order to obtain detailed information about the chemical composition of diesel and the distribution of different compound types in terms of its final boiling temperature from a single analysis. The total time elapsed from sample injection and signal processing to obtain final results is 90 minutes. This fact makes this methodology a new and very important tool for the decision making process concerning the most suitable final boiling temperature and the type of treatment of the product in order to obtain diesel that fulfills the international standards. The consistency and repeatability of the experimental results are demonstrated

  14. Continuous monitoring of a changing sample by multiplex gas chromatography

    Science.gov (United States)

    Valentin, Jose R.; Hall, Kirsten W.; Becker, Joseph F.

    1990-01-01

    Results are presented from a study in which a continuously changed gaseous sample was monitored by multiplex gas chromatography (MGC), using the exponential dilution (ED) technique of Ritter and Adams (1976) to change the composition and concentration of a gaseous mixture in such a way as to imitate changes in the atmospheric gases sampled by a descending aircraft. A calibration of the MGC system was performed with four different rates of sample dilution, and the errors resulting from various degrees of change in the sample concentration were determined.

  15. Flavor release measurement by atmospheric pressure chemical ionization ion trap mass spectrometry, construction of interface and mathematical modeling of release profiles

    DEFF Research Database (Denmark)

    Haahr, Anne-Mette; Madsen, Henrik; Smedsgaard, Jørn

    2003-01-01

    An instrumental on-line retronasal flavor analysis was developed to obtain information about the release of flavor compounds in expired air from humans during eating. The volatile flavor compounds were measured by ion trap mass spectrometry with an atmospheric pressure chemical ionization source...... (APCI). An interface was designed to sample the breath directly from the nose. The repeat-ability in vitro for seven different flavor compounds came out with relative standard derivation less than 10% in most cases, which is acceptable. In vitro quantification was carried out by a determination...... of the concentration in the gas phase over a flavor solution by GC/MS, followed by measurements of intensities by the APCI ion trap. Ion suppression by acetone in the breath was negligible at concentration levels relevant in these experiments. The instrumental limits of detection for menthone and menthol coincide...

  16. Quantification of prominent volatile compounds responsible for muskmelon and watermelon aroma by purge and trap extraction followed by gas chromatography-mass spectrometry determination.

    Science.gov (United States)

    Fredes, Alejandro; Sales, Carlos; Barreda, Mercedes; Valcárcel, Mercedes; Roselló, Salvador; Beltrán, Joaquim

    2016-01-01

    A dynamic headspace purge-and-trap (DHS-P&T) methodology for the determination and quantification of 61 volatile compounds responsible for muskmelon and watermelon aroma has been developed and validated. The methodology is based on the application of purge-and-trap extraction followed by gas chromatography coupled to (ion trap) mass spectrometry detection. For this purpose two different P&T sorbent cartridges have been evaluated. The influence of different extraction factors (sample weight, extraction time, and purge flow) on extraction efficiency has been studied and optimised using response surface methodology. Precision, expressed as repeatability, has been evaluated by analysing six replicates of real samples, showing relative standard deviations between 3% and 27%. Linearity has been studied in the range of 10-6130 ng mL(-1) depending on the compound response, showing coefficients of correlation between 0.995 and 0.999. Detection limits ranged between 0.1 and 274 ng g(-1). The methodology developed is well suited for analysis of large numbers of muskmelon and watermelon samples in plant breeding programs. Copyright © 2015 Elsevier Ltd. All rights reserved.

  17. Measurement of vapor pressure of organophosphorous compounds by gas chromatography

    International Nuclear Information System (INIS)

    Panneerselvam, K.; Brahmmananda Rao, C.V.S.; Antony, M.P.

    2016-01-01

    Dialkylalkyl phosphonates have been developed as an alternative solvent to TBP at our laboratory for separation of actinides. Several dialkylalkylphosphonates have been synthesized and the vapor pressure of all of them was determined using Gas Chromatography (GC) technique. In this technique, individual dialkylalkylphosphonates have been separated from a mixture using GC. Gas chromatography has been utilized as a successful technique in determining vapor pressure of homologous series and structurally similar compounds. GC retention time (t a ) is inversely proportional to the vapor pressure of the solute in solution of the stationary phase. This technique strongly depends on the linear correlation observed between 1n(p/p 0 ) of a reference compound and a target sample under investigation, where p is the vapor pressure for reference compound, p 0 = 101.325 kPa, and 1n(t 0 /t a ) where t 0 = 1 minute and t a = difference in retention times of the target compound and a nonretained compound, CH 2 Cl 2 , added. The retention time of reference (trialkyl phosphate) and target (dibutylalkyl phosphonates) compounds along with CH 2 Cl 2 has been obtained by gas chromatograph using a 4 m 10 % XE-60 packed column under isothermal conditions. Helium was used as carrier gas. As expected, the vapor pressure of reference as well as target compounds decreases with increasing molecular weight of organophosphorous compounds. The merits of this technique are its speed, accuracy and tiny volume of sample. Requirement of high purity sample in contrast to the conventional technique is also done away with this technique. (author)

  18. Gas chromatography-olfactometry analysis of the volatile compounds of two commercial Irish beef meats

    NARCIS (Netherlands)

    Machiels, D.; Ruth, van S.M.; Posthumus, M.A.; Istasse, L.

    2003-01-01

    The volatile flavour compounds of two commercial Irish beef meats (labelled as conventional and organic) were evaluated by gas chromatography-olfactometry and were identified by gas chromatography-mass spectrometry. The volatile compounds were isolated in a model mouth system. Gas

  19. Solute-solvent interaction parameters by gas chromatography.

    Science.gov (United States)

    Kováts, Ervin sz; Fóti, György; Dallos, András

    2004-08-13

    Gas-liquid distribution coefficients at ideal dilution in non-volatile solvents can be measured by gas chromatography. The numerical value of a coefficient depends on the choice of the concentration unit in the solvent and in the gas phase. The relationships between different coefficients characterizing gas-liquid equilibria are discussed and summarized. Coefficients determined at several temperatures permit calculation of the standard chemical potential difference of the solute with the ideal gas phase as reference as a function of temperature, the g-SPOT. Following the proposal of Kirchhoff the latter can be formulated as an equation with three constants. As in the gas phase the molecules of the solute have no interacting partners, the three constants, deltaH, deltaS and deltaC, characterize the interaction between solvent and solute molecules. They will be called the "solute-solvent interaction parameters". In the same system the values of these parameters depend on the choice of the distribution coefficient. Five different distribution coefficients result five sets of interaction parameters. It is shown that conversion of a parameter set to another implies additive corrections independent of the nature of the solute. If g-SPOT-s are measured in a series of solvents, the data may be used to calculate the corresponding liquid-liquid partition coefficients by electing one of the solvents as reference (l-SPOT). The corresponding "relative interaction parameters" can be calculated by simple substraction. In a second chapter the precautions are summarized, necessary for gas chromatographic determination of distribution coefficients and examples are given for interaction parameters in different systems. It is concluded that there are significant differences between g-SPOT-s related to different distribution coefficients. On the other hand, differences between l-SPOT-s are negligible.

  20. Graphitized carbon in gas-liquid-solid chromatography and gas chromatography/mass spectrometric analysis of high boiling hydrocarbon mixtures

    International Nuclear Information System (INIS)

    Ciccioli, P.; Hayes, J.M.; Rinaldi, G.; Denson, K.B.; Meinschein, W.G.

    1979-01-01

    Gas--liquid--solid chromatography (GLSC) employing a poly(phenyl ether) (PPE 20) liquid phase on graphitized carbon black (GCB) is applicable to the analyses of crude oils and distillates of sedimentary rocks. The elution of C 4 to C 40 hydrocarbons which consist of n-alkanes, isoprenoid-type alkanes, steranes, olefins, and aromatic hydrocarbons can be handled in a single GC run. A GLSC column in tandem with a mass spectrometer provides an excellent means for the identification of geochemically significant organic compounds in complex natural mixtures. 8 figures, 4 tables

  1. [Compound preservative and cyclamat determinated by gas chromatography].

    Science.gov (United States)

    Xin, Ruozhu; Ding, Mei; Zheng, Xianguang; Li, Yajuan

    2008-07-01

    To establish a gas chromatography method for synchronous determination of six preservatives and cyclamat in cake and pastry. The pre-treatment of complicated compound was finished by dialysis cleaning technology. The interference of the complicated foundation body in the cake and pastry was removed by the best dialysis condition: 2 g/L NaOH of dialysis fluid was dialyzed at the temperature of 25 degrees C for 24h, and the six preservatives and cyclamat (sorbic acid, benzoic acid, dehydroacetic acid, ethylparabenum, propylparabenum, butylparabenun and sodium cyclamate) were synchronously seperated by 60-80 mesh Chromosorb WAW DMCS glass packing column of intercoated 5% DEGS + 1% H3 PO4. The seven components in the sample had a good lining relation at the concentration 100 -5000 mg/L when the external standard method was used, and their correlation coefficients were 0.9993-0.9998, and their average recovery rates were 87.5%-101.9%, and their relative standard deviations were 0.64%-3.3%, and detection limits were 1.1-8.8 mg/L. This method could be used to quickly analyse the compound preservatives of the large batch cake and pastry through the common gas chromatography and packed column and this method was simple, accurate and quick.

  2. Rapid Identification of Airborne Biological Particles by Flow Cytometry, Gas Chromatography, and Genetic Probes

    National Research Council Canada - National Science Library

    Wick, Charles

    1997-01-01

    .... Physical characteristics of the particles, it was proposed, could be detected by flow cytometry, while their biochemical profiles could be determined by gas chromatography, and their genetic identity...

  3. Ionization of Gas-Phase Polycyclic Aromatic Hydrocarbons in Electrospray Ionization Coupled with Gas Chromatography.

    Science.gov (United States)

    Cha, Eunju; Jeong, Eun Sook; Han, Sang Beom; Cha, Sangwon; Son, Junghyun; Kim, Sunghwan; Oh, Han Bin; Lee, Jaeick

    2018-03-20

    Herein, gas-phase polycyclic aromatic hydrocarbons (PAHs) as nonpolar compounds were ionized to protonated molecular ions [M + H] + without radical cations and simultaneously analyzed using gas chromatography (GC)/electrospray ionization (ESI)-tandem mass spectrometry (MS/MS). The ionization profile, dissociation, and sensitivity were first investigated to understand the significant behavior of gas-phase PAHs under ESI. The formation of protonated molecular ions of PAHs was distinguished according to the analyte phase and ESI spray solvents. The protonated PAHs exhibited characteristic dissociations, such as H-loss, H 2 -loss, and acetylene-loss, via competition of internal energy. In addition, GC/ESI-MS/MS resulted in relatively lower concentration levels (better sensitivity) for the limits-of-detection (LODs) of PAHs than liquid chromatography (LC)/ESI-MS/MS, and it seems to result from the characteristic ionization mechanism of the gas-phase analyte under ESI. Furthermore, the LODs of gas-phase PAHs depended on molecular weight and proton affinity (PA). Consequently, we demonstrated the relationship among the analyte phases, sensitivities, and structural characteristics (molecular weight and PA) under ESI. The gas-phase PAHs provided enhanced protonation efficiency and sensitivity using GC/ESI-MS/MS, as their molecular weight and PA increased. Based on these results, we offered important information regarding the behavior of gas-phase analytes under ESI. Therefore, the present GC/ESI-MS/MS method has potential as an alternative method for simultaneous analysis of PAHs.

  4. Characterization of the fermentation process by gas chromatography Lasiodiplodia theobromae and gas chromatography coupled with mass spectrometry

    International Nuclear Information System (INIS)

    Castillo Portela, Grolamys; Eng Sanchez, Felipe; Nogueiras Lima, Clara

    2014-01-01

    Lasiodiplodia theobromae is a fungus, which has been reported by some authors as a high yield producer of the phytohormone jasmonic acid (JA). An indigenous strain of this fungus has been used for producing a fermentation broth with a high JA concentration by the Cuban Research Institute for Sugar Cane Derivatives (ICIDCA), registered as BIOJAS. The broth has been applied to some agricultural crops and demonstrated its economic feasibility as plant growth regulator and biological control of various phytopathogenic microorganisms and pests. Both fermentation broth and biomass from this fungus contain some other metabolites having bioactive properties, for instance, fatty acids. This paper shows the composition and quantification of fatty acids in the biomass using Gas Chromatography (GC) and the identification of substances profile in fermentation broth by Gas Chromatography coupled to Mass Spectrometry (GC-MS). The most fatty acids in the biomass are palmitic, stearic, oleic, linoleic and linolenic acids, being oleic acid the major component. On the other hand, 2,32 % of fatty acid esters; 2,47 % of alkenes; 14,40 % of alcohols; 30,15 % of aldehydes and 21,73 % of paraffins were detected in the composition of fermentation broth

  5. The ReA electron-beam ion trap charge breeder for reacceleration of rare isotopes

    Energy Technology Data Exchange (ETDEWEB)

    Lapierre, A.; Schwarz, S.; Kittimanapun, K.; Fogleman, J.; Krause, S.; Nash, S.; Rencsok, R.; Tobos, L.; Perdikakis, G.; Portillo, M.; Rodriguez, J. A.; Wittmer, W.; Wu, X.; Bollen, G.; Leitner, D.; Syphers, M. [National Superconducting Cyclotron Laboratory (NSCL), Michigan State University (MSU), 640 South Shaw Lane, East Lansing, MI 48824 (United States); Collaboration: ReA Team

    2013-04-19

    ReA is a post-accelerator at the National Superconducting Cyclotron Laboratory at Michigan State University. ReA is designed to reaccelerate rare isotopes to energies of a few MeV/u following production by projectile fragmentation and thermalization in a gas cell. The facility consists of four main components: an electron-beam ion trap (EBIT) charge breeder, an achromatic charge-over-mass (Q/A) separator, a radio-frequency quadrupole accelerator, and a superconducting radio-frequency linear accelerator. The EBIT charge breeder was specifically designed to efficiently capture continuous beams of singly charged ions injected at low energy (<60 keV), charge breed in less than 50 ms, and extract highly charged ions to the Q/A separator for charge-state selection and reacceleration through the accelerator structures. The use of highly charged ions to reach high beam energies is a key aspect that makes ReA a compact and cost-efficient post-accelerator. The EBIT is characterized by a high-current electron gun, a long multi-electrode trap structure and a dual magnet to provide both the high electron-beam current density necessary for fast charge breeding of short-lived isotopes as well as the high capture probability of injected beams. This paper presents an overview and the status of the ReA EBIT, which has extracted for reacceleration tests stable {sup 20}Ne{sup 8+} ion beams produced from injected gas and more recently {sup 39}K{sup 16+} beams by injecting stable {sup 39,41}K{sup +} ions from an external ion source.

  6. Separation of krypton from dissolver off-gas of a reprocessing plant using preparative gas chromatography

    International Nuclear Information System (INIS)

    Matoni, M.

    1984-02-01

    Kr-85 can be separated from the pre-purified purge air in the final processing step of the purification phase for dissolver off-gases of a reprocessing plant with the aid of preparative gas chromatography. Activated carbon adsorbers in combination with helium as carrier gas permits maximum gas mixture through-flow. A separation temperature of 30 0 C is considered optimal. An adsorbent volume of 40 dm 3 is necessary for processing the residual gas flow of 2.5 Nm 3 /h; the adsorbent is divided between 2 columns linked in series each of which are 2 m long with an internal diameter of 100 mm. The helium flow required is five times greater than the off-gas flow. The degree of purity for krypton is greater than 90% for a decontamination factor of greater than 1000. (orig./HP) [de

  7. Chemical discrimination in turbulent gas mixtures with MOX sensors validated by gas chromatography-mass spectrometry.

    Science.gov (United States)

    Fonollosa, Jordi; Rodríguez-Luján, Irene; Trincavelli, Marco; Vergara, Alexander; Huerta, Ramón

    2014-10-16

    Chemical detection systems based on chemo-resistive sensors usually include a gas chamber to control the sample air flow and to minimize turbulence. However, such a kind of experimental setup does not reproduce the gas concentration fluctuations observed in natural environments and destroys the spatio-temporal information contained in gas plumes. Aiming at reproducing more realistic environments, we utilize a wind tunnel with two independent gas sources that get naturally mixed along a turbulent flow. For the first time, chemo-resistive gas sensors are exposed to dynamic gas mixtures generated with several concentration levels at the sources. Moreover, the ground truth of gas concentrations at the sensor location was estimated by means of gas chromatography-mass spectrometry. We used a support vector machine as a tool to show that chemo-resistive transduction can be utilized to reliably identify chemical components in dynamic turbulent mixtures, as long as sufficient gas concentration coverage is used. We show that in open sampling systems, training the classifiers only on high concentrations of gases produces less effective classification and that it is important to calibrate the classification method with data at low gas concentrations to achieve optimal performance.

  8. Development and validation of a new analytical method for the determination of 1,4-dichlorobenzene in honey by gas chromatography-isotope dilution mass spectrometry after steam-distillation.

    Science.gov (United States)

    Botitsi, E V; Kormali, P N; Kontou, S N; Economou, A; Tsipi, D F

    2006-10-02

    A simple, fast, sensitive and robust analytical method using gas chromatography (GC)-isotope dilution mass spectrometry (MS) was developed and validated for the identification and quantification of 1,4-dichlorobenzene (p-DCB) residues in honey samples. The proposed methodology is based on steam-distillation using a Clevenger-type apparatus followed by gas chromatography-mass spectrometry (GC-MS) in the selected ion monitoring (SIM) mode employing the isotopically labeled analogue d4-1,4-dichlorobenzene (d4-p-DCB) as internal standard (IS). Validation of the method was performed in two different GC-MS systems, using quadrupole MS (QMS) and ion-trap MS (ITMS) detectors, with no statistically significant differences between two. Recoveries were better than 91% with percent relative standard deviations lower than 12%. The instrumental limits of detection were 1 microg kg(-1) in the GC-ITMS system and 0.6 microg kg(-1) in the GC-QMS system. The expanded uncertainty was estimated as 17% at the currently accepted "action level" of 10 microg kg(-1). The method was applied to the analysis of 310 honey samples in an extensive national monitoring study. A quality control (QC) system applied during the assays has demonstrated a good performance and long-term stability over a period of more than 8 months of continuous operation.

  9. Ion trap mass spectrometry on a comet nucleus: the Ptolemy instrument and the Rosetta space mission.

    Science.gov (United States)

    Todd, John F J; Barber, Simeon J; Wright, Ian P; Morgan, Geraint H; Morse, Andrew D; Sheridan, Simon; Leese, Mark R; Maynard, Jon; Evans, Suzanne T; Pillinger, Colin T; Drummond, Duncan L; Heys, Samantha C; Huq, S Ejaz; Kent, Barry J; Sawyer, Eric C; Whalley, Martin S; Waltham, Nicholas R

    2007-01-01

    In May 2014, the Rosetta spacecraft is scheduled to rendezvous with the comet Churyumov-Gerasimenko ('67P'). One of the instruments on board the 'Lander' which will descend on to the surface of the comet is a miniaturised GC/MS system that incorporates an ion trap mass spectrometer, specially developed for isotope ratio analysis. This article describes the development and optimisation of the ion trap for this unique application, and presents a summary of the range of pre-programmed experiments that will contribute to the characterisation of the solid and volatile cometary materials. Copyright 2006 John Wiley & Sons, Ltd.

  10. A denuder-impinger system with in situ derivatization followed by gas chromatography-mass spectrometry for the determination of gaseous iodine-containing halogen species.

    Science.gov (United States)

    Huang, Ru-Jin; Hoffmann, Thorsten

    2008-11-14

    Reactive iodine species have been suggested to play an important role in the atmosphere (e.g. tropospheric ozone depletion, coastal new particle formation). However, there still exist major uncertainties about their atmospheric chemistry, mostly due to the lack of analytical approaches for the accurate speciation of certain key compounds. In this study, 1,3,5-trimethoxybenzene (1,3,5-TMB)-coated denuder proved to be suitable for the differentiation between gaseous interhalogens (iodine monochloride (ICl), iodine monobromide (IBr)) and molecular iodine (I2) based on a selective collection/derivatization method. The results of the denuder sampling were compared with the results of impinger sampling in water, methanol and carbon tetrachloride solutions of 1,3,5-TMB. ICl and IBr are converted into 1-iodo-2,4,6-trimethoxybenzene (1-iodo-2,4,6-TMB) and 1-bromo-2,4,6-trimethoxybenzene (1-bromo-2,4,6-TMB), respectively, in the denuder systems. The respective collection efficiency is 99.2% for ICl and 92.6% for IBr, at 500mLmin(-1) gas flow rate. The collection efficiency for I2 is lower than 1% in the same denuder system, but significantly increases to about 90% in the aqueous 1,3,5-TMB loaded impinger. The denuder-impinger coupled system was then used to differentiate and to collect the ICl, IBr and I2 gas mixtures, followed by gas chromatography-ion trap mass spectrometry (GC-MS) determination. The precision of the method is in general better than 9.1%. The parameters affecting denuder operation including sampling flow rate, sampling duration, and relative humidity have been evaluated. The presented method provides an attractive protocol for iodine species analysis for atmospheric chemistry research.

  11. Feedlot lamb meat fatty acids profile characterization employing gas chromatography

    Directory of Open Access Journals (Sweden)

    M.I. Cruz-Gonzalez

    2014-06-01

    Full Text Available Fat is an important constituent in diet, not only as an energy source, but for its essential fatty acids associated to fats in foods, considering that some polyunsaturated fatty acids like linoleic, linolenic and arachidonic cannot be synthesized by superior animals like humans. Scientific evidence show that the fatty acids ingest can affect the thrombotic tendency, cardiac rhythm, endothelial function systematic inflammation, insulin sensibility and oxidative stress. Samples from 21 ovine crossbreds from Pelibuey, Blackbelly, Dorper and Katahadin (40 kg average weight feed with corn based balanced diets were taken from loin area 18 h after refrigeration. Saturated and polyunsaturated fatty acids levels were analyzed by gas chromatography. Results in this work showed that the healthy fatty acids levels are higher as compared to saturated fatty acids levels, indicating that this meat can influence consumer’s buying choice decision regarded to their health.

  12. Selective data reduction in gas chromatography/infrared spectrometry

    International Nuclear Information System (INIS)

    Pyo, Dong Jin; Shin, Hyun Du

    2001-01-01

    As gas chromatography/infrared spectrometry (GC/IR) becomes routinely available, methods must be developed to deal with the large amount of data produced. We demonstrate computer methods that quickly search through a large data file, locating those spectra that display a spectral feature of interest. Based on a modified library search routine, these selective data reduction methods retrieve all or nearly all of the compounds of interest, while rejection the vast majority of unrelated compounds. To overcome the shifting problem of IR spectra, a search method of moving the average pattern was designed. In this moving pattern search, the average pattern of a particular functional group was not held stationary, but was allowed to be moved a little bit right and left

  13. Low thermal mass gas chromatography: principles and applications.

    Science.gov (United States)

    Luong, Jim; Gras, Ronda; Mustacich, Robert; Cortes, Hernan

    2006-01-01

    In gas chromatography (GC), temperature programming is often considered to be the second most important parameter to control, the first being column selectivity. A radically new GC technology to achieve ultrafast temperature programming with an unprecedented cool down time and low power consumption has recently become available. This technology is referred to as low thermal mass GC (LTMGC). Though the technology has its roots in resistive heating, which forms the basis of principle and design concept, the approach taken to achieve ultrafast heating and cool down time by LTMGC represents a significant break-through in GC. Despite some rectifiable shortcomings, LTMGC has proven to be an ideal methodology to deliver near/real time GC data, high precision, and high throughput applications. It is a new approach for modern high-speed GC. This paper documents the fundamental design principles behind LTMGC, performance data, and examples of applications investigated.

  14. Design, testing, and simulation of microscale gas chromatography columns

    Energy Technology Data Exchange (ETDEWEB)

    Hudson, M.L.; Kottenstette, R.; Matzke, C.M.; Frye-Mason, G.C.; Shollenberger, K.A.; Adkins, D.R.; Wong, C.C.

    1998-08-01

    A microscale gas chromatography column is one component in a microscale chemistry laboratory for detecting chemical agents. Several columns were fabricated using the Bosch etch process which allows deep, high aspect ratio channels of rectangular cross-section. A design tool, based on analytical models, was developed to evaluate the effects of operating conditions and column specifications on separation resolution and time. The effects of slip flow, channel configuration, and cross-sectional shape were included to evaluate the differences between conventional round, straight columns and the microscale rectangular, spiral columns. Experimental data were obtained and compared with the predicted flowrates and theoretical number of plates. The design tool was then employed to select more optimum channel dimensions and operating conditions for high resolution separations.

  15. Development of a Linear Ion Trap Mass Spectrometer (LITMS) Investigation for Future Planetary Surface Missions

    Science.gov (United States)

    Brinckerhoff, W.; Danell, R.; Van Ameron, F.; Pinnick, V.; Li, X.; Arevalo, R.; Glavin, D.; Getty, S.; Mahaffy, P.; Chu, P.; hide

    2014-01-01

    Future surface missions to Mars and other planetary bodies will benefit from continued advances in miniature sensor and sample handling technologies that enable high-performance chemical analyses of natural samples. Fine-scale (approx.1 mm and below) analyses of rock surfaces and interiors, such as exposed on a drill core, will permit (1) the detection of habitability markers including complex organics in association with their original depositional environment, and (2) the characterization of successive layers and gradients that can reveal the time-evolution of those environments. In particular, if broad-based and highly-sensitive mass spectrometry techniques could be brought to such scales, the resulting planetary science capability would be truly powerful. The Linear Ion Trap Mass Spectrometer (LITMS) investigation is designed to conduct fine-scale organic and inorganic analyses of short (approx.5-10 cm) rock cores such as could be acquired by a planetary lander or rover arm-based drill. LITMS combines both pyrolysis/gas chromatograph mass spectrometry (GCMS) of sub-sampled core fines, and laser desorption mass spectrometry (LDMS) of the intact core surface, using a common mass analyzer, enhanced from the design used in the Mars Organic Molecule Analyzer (MOMA) instrument on the 2018 ExoMars rover. LITMS additionally features developments based on the Sample Analysis at Mars (SAM) investigation on MSL and recent NASA-funded prototype efforts in laser mass spectrometry, pyrolysis, and precision subsampling. LITMS brings these combined capabilities to achieve its four measurement objectives: (1) Organics: Broad Survey Detect organic molecules over a wide range of molecular weight, volatility, electronegativity, concentration, and host mineralogy. (2) Organic: Molecular Structure Characterize internal molecular structure to identify individual compounds, and reveal functionalization and processing. (3) Inorganic Host Environment Assess the local chemical

  16. Gas Chromatography-Mass Spectroscopic (GC-MS) Analysis of n ...

    African Journals Online (AJOL)

    tuber-regium (synonym Pleurotus tuber regium) using gas chromatography-mass spectroscopic (GC-. MS) techniques. Methods: The n-hexane extract of the sclerotia ... Soxhlet extraction and analysed using gas chromatography-mass spectroscopic (MS) techniques. ..... Phytochemical composition of Pleurotus tuber regium.

  17. Enantioselective determination of triazole fungicide simeconazole in vegetables, fruits, and cereals using modified QuEChERS (quick, easy, cheap, effective, rugged and safe) coupled to gas chromatography/tandem mass spectrometry

    International Nuclear Information System (INIS)

    Li Jing; Dong Fengshou; Xu Jun; Liu Xingang; Li Yuanbo; Shan Weili; Zheng Yongquan

    2011-01-01

    Highlights: · Simeconazole enantiomers were baseline separated by gas chromatography. · Optical pure enantiomer was prepared and their elution order was distinguished. · Clean-up/enrichment procedure was based on the modification of QuEChERS method. · Cleanup step was further improved by solid phase extraction (SPE) technology. · Analysis of samples was accomplished by GC-MS/MS. - Abstract: A rapid and effective method for enantioselective determination of simeconazole enantiomers in food products (cucumber, tomato, apple, pear, wheat and rice) has been developed. The enantiomers were resolved by capillary gas chromatography (GC) using a commercial chiral column (BGB-172) and a temperature program from 150 deg. C (held for 1 min) and then raised at 10 deg. C min -1 to 240 deg. C (held for 10 min). This enantioselective gas chromatographic separation was combined with a clean-up/enrichment procedure based on the modification of QuEChERS (quick, easy, cheap, effective, rugged and safe) method. Co-extractives were removed with graphitized carbon black/primary secondary amine (GCB/PSA) solid-phase extraction (SPE) cartridges using acetonitrile:toluene (3:1, v/v) as eluent. Gas chromatography/ion trap mass spectrometry (GC-ITMS) with electron ionization (EI) was then used for qualitative and quantitative determination of the simeconazole enantiomers. Two precursor-to-product ion transitions (m/z 121-101 and 195-153) with the best signal intensity were chosen to build the multiple-reaction monitoring (MRM) acquisition method. The limits of detection for each enantiomer of simeconazole in six food products ranged between 0.4 and 0.9 μg kg -1 , which were much lower than maximum residue levels (MRLs) established by Japan. The methodology was successfully applied for the enantioselective analysis of simeconazole enantiomers in real samples, indicating its efficacy in investigating the environmental stereochemistry of simeconazole in food matrix.

  18. Recent advances and applications of gas chromatography vacuum ultraviolet spectroscopy.

    Science.gov (United States)

    Santos, Inês C; Schug, Kevin A

    2017-01-01

    The vacuum ultraviolet spectrophotometer was developed recently as an alternative to existing gas chromatography detectors. This detector measures the absorption of gas-phase chemical species in the range of 120-240 nm, where all chemical compounds present unique absorption spectra. Therefore, qualitative analysis can be performed and quantification follows standard Beer-Lambert law principles. Different fields of application, such as petrochemical, food, and environmental analysis have been explored. Commonly demonstrated is the capability for facile deconvolution of co-eluting analytes. The concept of additive absorption for co-eluting analytes has also been advanced for classification and speciation of complex mixtures using a data treatment procedure termed time interval deconvolution. Furthermore, pseudo-absolute quantitation can be performed for system diagnosis, as well as potentially calibrationless quantitation. In this manuscript an overview of these features, the vacuum ultraviolet spectrophotometer instrumentation, and performance capabilities are given. A discussion of the applications of the vacuum ultraviolet detector is provided by describing and discussing the papers published thus far since 2014. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  19. Chromatography.

    Science.gov (United States)

    Brantley, L. Reed, Sr.; Demanche, Edna L.; Klemm, E. Barbara; Kyselka, Will; Phillips, Edwin A.; Pottenger, Francis M.; Yamamoto, Karen N.; Young, Donald B.

    This booklet presents some activities on chromatography. Directions for preparing leaf pigment extracts using alcohol are given, and paper chromatography and thin-layer chromatography are described as modifications of the basic principles of chromatography. (KHR)

  20. Phytochemical Profile of Erythrina variegata by Using High-Performance Liquid Chromatography and Gas Chromatography-Mass Spectroscopy Analyses

    OpenAIRE

    Suriyavathana Muthukrishnan; Subha Palanisamy; Senthilkumar Subramanian; Sumathi Selvaraj; Kavitha Rani Mari; Ramalingam Kuppulingam

    2016-01-01

    Natural products derived from plant sources have been utilized to treat patients with numerous diseases. The phytochemical constituents present in ethanolic leaf extract of Erythrina variegata (ELEV) were identified by using high-performance liquid chromatography (HPLC) and gas chromatography-mass spectroscopy (GC-MS) analyses. Shade dried leaves were powdered and extracted with ethanol for analyses through HPLC to identify selected flavonoids and through GC-MS to identify other molecules. Th...

  1. Carbon monoxide measurement by gas chromatography; Mesure du monoxyde de carbone par chromatographie en phase gazeuse

    Energy Technology Data Exchange (ETDEWEB)

    Gros, V.; Sarda-Esteve, R.; Bonsang, B.; Ramonet, M.

    1998-09-01

    Although carbon monoxide (CO) is present in trace quantities in the atmosphere (0.1 ppm -or parts per million in volume- on average), the study of this gas is important. Indeed, its impact on human can be dangerous at high level of concentration on the hand and it constitutes one of the main precursor of ozone in presence of concentration on the one hand and it constitutes one of the main precursor of ozone in presence of other pollutants on the other hand. Finally, CO affects the levels of several important greenhouse gases, through its reaction with hydroxyl radicals (OH). CO is measured in the atmosphere since the mid 60's by various methods. Among them, gas chromatography has the advantage to combine a low detection limit with a high precision. This report details the improvements made on the measurement analyser which allowed to perform automatic CO measurements in remote areas with low mixing ratios of carbon monoxide. This report describes some quality tests and the results of various applications. (authors)

  2. Practical aspects of trapped ion mass spectrometry, 5 applications of ion trapping devices

    CERN Document Server

    March, Raymond E

    2009-01-01

    Examines ion/neutral and ion/ion reactions, ion spectroscopy, and the structural characterization of proteins and peptides using quadropole ion trap mass spectrometry, Fourier transform - ion cyclotron resonance (FT-ICR) mass spectrometry, and traveling wave ion mobility mass spectrometry.

  3. X-ray spectroscopy of highly-ionized atoms in an electron beam ion trap (EBIT)

    International Nuclear Information System (INIS)

    Marrs, R.E.; Bennett, C.; Chen, M.H.

    1988-01-01

    An Electron Beam Ion Trap at Lawrence Livermore National Laboratory is being used to produce and trap very-highly-charged-ions (q /le/ 70+) for x-ray spectroscopy measurements. Recent measurements of dielectronic recombination, electron impact excitation and transition energies are presented. 15 refs., 12 figs., 1 tab

  4. Spectroscopy of highly charged tungsten ions with Electron Beam Ion Traps

    International Nuclear Information System (INIS)

    Sakaue, Hiroyuki A.; Kato, Daiji; Morita, Shigeru; Murakami, Izumi; Yamamoto, Norimasa; Ohashi, Hayato; Yatsurugi, Junji; Nakamura, Nobuyuki

    2013-01-01

    We present spectra of highly charged tungsten ions in the extreme ultra-violet (EUV) by using electron beam ion traps. The electron energy dependence of spectra is investigated of electron energies from 490 to 1440 eV. Previously unreported lines are presented in the EUV range, and some of them are identified by comparing the wavelengths with theoretical calculations. (author)

  5. EUV spectrum of highly charged tungsten ions in electron beam ion trap

    International Nuclear Information System (INIS)

    Sakaue, H.A.; Kato, D.; Murakami, I.; Nakamura, N.

    2016-01-01

    We present spectra of highly charged tungsten ions in the extreme ultra-violet (EUV) by using electron beam ion traps. The electron energy dependence of spectra was investigated for electron energy from 540 to 1370 eV. Previously unreported lines were presented in the EUV range, and comparing the wavelengths with theoretical calculations identified them. (author)

  6. The JPL Hg(sup +) Extended Linear Ion Trap Frequency Standard: Status, Stability, and Accuracy Prospects

    Science.gov (United States)

    Tjoelker, R. L.; Prestage, J. D.; Maleki, L.

    1996-01-01

    Microwave frequency standards based on room temperature (sup 199)Hg(sup +) ions in a Linear Ion Trap (LITS) presently achieve a Signal to Noise and line Q inferred short frequency stability. Long term stability has been measured for averaging intervals up to 5 months with apparent sensitivity to variations in ion number/temperature limiting the flicker floor.

  7. Microfabricated planar glass gas chromatography with photoionization detection.

    Science.gov (United States)

    Lewis, Alastair C; Hamilton, Jacqueline F; Rhodes, Christopher N; Halliday, Jaydene; Bartle, Keith D; Homewood, Philip; Grenfell, Robin J P; Goody, Brian; Harling, Alice M; Brewer, Paul; Vargha, Gergely; Milton, Martin J T

    2010-01-29

    We report the development of a microfabricated gas chromatography system suitable for the separation of volatile organic compounds (VOCs) and compatible with use as a portable measurement device. Hydrofluoric acid etching of 95x95mm Schott B270 wafers has been used to give symmetrical hemi-spherical channels within a glass substrate. Two matching glass plates were subsequently cold bonded with the channels aligned; the flatness of the glass surfaces resulted in strong bonding through van der Waals forces. The device comprised gas fluidic interconnections, injection zone and 7.5 and 1.4m long, 320microm internal diameter capillaries. Optical microscopy confirmed the capillaries to have fully circular channel profiles. Direct column heating and cooling could be achieved using a combination of resistive heaters and Peltier devices. The low thermal conductivity of glass allowed for multiple uniform temperature zones to be achieved within a single glass chip. Temperature control over the range 10-200 degrees C was achieved with peak power demand of approximately 25W. The 7.5m capillary column was static coated with a 2microm film of non-polar dimethylpolysiloxane stationary phase. A standard FID and a modified lightweight 100mW photoionization detector (PID) were coupled to the column and performance tested with gas mixtures of monoaromatic and monoterpene species at the parts per million concentration level. The low power GC-PID device showed good performance for a small set of VOCs and sub ng detection sensitivity to monoaromatics. Copyright (c) 2009 Elsevier B.V. All rights reserved.

  8. Final Report - Advanced Ion Trap Mass Spectrometry Program - Oak Ridge National Laboratory - Sandia National Laboratory

    Energy Technology Data Exchange (ETDEWEB)

    Whitten, W.B.

    2002-12-18

    This report covers the three main projects that collectively comprised the Advanced Ion Trap Mass Spectrometry Program. Chapter 1 describes the direct interrogation of individual particles by laser desorption within the ion trap mass spectrometer analyzer. The goals were (1) to develop an ''intelligent trigger'' capable of distinguishing particles of biological origin from those of nonbiological origin in the background and interferent particles and (2) to explore the capability for individual particle identification. Direct interrogation of particles by laser ablation and ion trap mass spectrometry was shown to have good promise for discriminating between particles of biological origin and those of nonbiological origin, although detailed protocols and operating conditions were not worked out. A library of more than 20,000 spectra of various types of biological particles has been assembled. Methods based on multivariate analysis and on neural networks were used to discriminate between particles of biological origin and those of nonbiological origin. It was possible to discriminate between at least some species of bacteria if mass spectra of several hundred similar particles were obtained. Chapter 2 addresses the development of a new ion trap mass analyzer geometry that offers the potential for a significant increase in ion storage capacity for a given set of analyzer operating conditions. This geometry may lead to the development of smaller, lower-power field-portable ion trap mass spectrometers while retaining laboratory-scale analytical performance. A novel ion trap mass spectrometer based on toroidal ion storage geometry has been developed. The analyzer geometry is based on the edge rotation of a quadrupolar ion trap cross section into the shape of a torus. Initial performance of this device was poor, however, due to the significant contribution of nonlinear fields introduced by the rotation of the symmetric ion-trapping geometry. These

  9. Single solid phase extraction method for the simultaneous analysis of polar and non-polar pesticides in urine samples by gas chromatography and ultra high pressure liquid chromatography coupled to tandem mass spectrometry.

    Science.gov (United States)

    Cazorla-Reyes, Rocío; Fernández-Moreno, José Luis; Romero-González, Roberto; Frenich, Antonia Garrido; Vidal, José Luis Martínez

    2011-07-15

    A new multiresidue method has been developed and validated for the simultaneous extraction of more than two hundred pesticides, including non-polar and polar pesticides (carbamates, organochlorine, organophosphorous, pyrethroids, herbicides and insecticides) in urine at trace levels by gas and ultra high pressure liquid chromatography coupled to ion trap and triple quadrupole mass spectrometry, respectively (GC-IT-MS/MS, UHPLC-QqQ-MS/MS). Non-polar and polar pesticides were simultaneously extracted from urine samples by a simple and fast solid phase extraction (SPE) procedure using C(18) cartridges as sorbent, and dichloromethane as elution solvent. Recovery was in the range of 60-120%. Precision values expressed as relative standard deviation (RSD) were lower than 25%. Identification and confirmation of the compounds were performed by the use of retention time windows, comparison of spectra (GC-amenable compounds) or the estimation of the ion ratio (LC-amenable compounds). For GC-amenable pesticides, limits of detection (LODs) ranged from 0.001 to 0.436 μg L(-1) and limits of quantification (LOQs) from 0.003 to 1.452 μg L(-1). For LC-amenable pesticides, LODs ranged from 0.003 to 1.048 μg L(-1) and LOQs ranged from 0.011 to 3.494 μg L(-1). Finally, the optimized method was applied to the analysis of fourteen real samples of infants from agricultural population. Some pesticides such as methoxyfenozide, tebufenozide, piperonyl butoxide and propoxur were found at concentrations ranged from 1.61 to 24.4 μg L(-1), whereas methiocarb sulfoxide was detected at trace levels in two samples. Copyright © 2011 Elsevier B.V. All rights reserved.

  10. Advanced Quadrupole Ion Trap Instrumentation for Low Level Vehicle Emissions Measurements

    International Nuclear Information System (INIS)

    McLuckey, S.A.

    1997-01-01

    Quadrupole ion trap mass spectrometry has been evaluated for its potential use in vehicle emissions measurements in vehicle test facilities as an analyzer for the top 15 compounds contributing to smog generation. A variety of ionization methods were explored including ion trap in situ chemical ionization, atmospheric sampling glow discharge ionization, and nitric oxide chemical ionization in a glow discharge ionization source coupled with anion trap mass spectrometer. Emphasis was placed on the determination of hydrocarbons and oxygenated hydrocarbons at parts per million to parts per billion levels. Ion trap in situ water chemical ionization and atmospheric sampling glow discharge ionization were both shown to be amendable to the analysis of arenes, alcohols, aldehydes and, to some degree, alkenes. Atmospheric sampling glow discharge also generated molecular ions of methy-t-butyl ether (MTBE). Neither of these ionization methods, however, were found to generate diagnostic ions for the alkanes. Nitric oxide chemical ionization, on the other hand, was found to yield diagnostic ions for alkanes, alkenes, arenes, alcohols, aldehydes, and MTBE. The ability to measure a variety of hydrocarbons present at roughly 15 parts per billion at measurement rates of 3 Hz was demonstrated. All of the ions with potential to serve as parent ions in a tandem mass spectrometry experiment were found to yield parent-to-product conversion efficiencies greater than 75%. The flexibility afforded to the ion trap by use of tailored wave-forms applied to the end-caps allows parallel monitoring schemes to be devised that provide many of the advantages of tandem mass spectrometry without major loss in measurement rate. A large loss in measurement rate would ordinarily result from the use of conventional tandem mass spectrometry experiments carried out in series for a large number of targeted components. These results have demonstrated that the ion trap has an excellent combination of

  11. Observation and mitigation of ion trapping in Indus-2

    Indian Academy of Sciences (India)

    p = nkT,. (1) where k is the Boltzmann's constant, p is the pressure in Pascal and T is the temperature in K. So, with 1 nTorr pressure in the vacuum chamber, the molecular density of gas is. 3.2×1013 m. −3 . Normally, hydrogen (H2), carbon monoxide (CO), carbon dioxide (CO2),. Table 1. Parameters of Indus-2. Energy. E.

  12. Pre-electrospray ionisation manifold methylation and post-electrospray ionisation manifold cleavage/ion cluster formation observed during electrospray ionisation of chloramphenicol in solutions of methanol and acetonitrile for liquid chromatography-mass spectrometry employing a commercial quadrupole ion trap mass analyser.

    Science.gov (United States)

    Sichilongo, Kwenga F; Famuyiwa, Samson O; Kibechu, Rose

    2011-01-01

    We have observed unusual mass spectra of chloramphenicol (CAP) in solutions of methanol or acetonitrile showing intense ions at m/z 297, m/z 311, m/z 325 and m/z 339. The observed ions were different from those which are traditionally observed in the full scan ESI mass spectra of CAP with ions of m/z 321, m/z 323 and m/z 325. We have evidence to show that this process starts with offline methylation of CAP in solutions of methanol or acetonitrile to give m/z 339. Investigations using nuclear magnetic resonance (NMR) spectroscopy showed that there is a methylene group somewhere within the CAP molecule but not attached to any of the carbon atoms when the CAP is dissolved in methanol or acetonitrile before infusion into the mass spectrometer. The possible locations of attachment were speculated to be the electronegative atoms apart from the chlorine atoms due to valence considerations. The methylene group is attached to the nitrogen atom and forms a bond as observed in the MS/MS spectra of m/z 297, m/z 311, m/z 325 and m/z 339 which give m/z 183 as the base peak in all cases. Further experiments showed that there is cleavage of the methylated CAP molecule followed by cluster ion formation involving addition of methylene groups to the CAP fragment with m/z 183 to produce ions of m/z including m/z 297, m/z 311, m/z 325 and m/z 339. This process occurs in the mass spectrometer in the region housing the tube lens and is triggered when the ions are accelerated through this region by application of a negative tube lens offset voltage. This region affords collision of the charged droplets with a collision gas in this case nitrogen to strip the droplets of their solvent molecules. Experiments to follow the intensities of m/z 183, m/z 311, m/z 321, m/z 323, m/z 325 and m/z 339 as the tube lens offset voltage was varied were done in which the intensities of m/z 311, m/z 325 and m/z 339 were observed to be at their peak when the tube lens offset voltage was set at -40 V. When

  13. Recent applications of gas chromatography with high-resolution mass spectrometry.

    Science.gov (United States)

    Špánik, Ivan; Machyňáková, Andrea

    2018-01-01

    Gas chromatography coupled to high-resolution mass spectrometry is a powerful analytical method that combines excellent separation power of gas chromatography with improved identification based on an accurate mass measurement. These features designate gas chromatography with high-resolution mass spectrometry as the first choice for identification and structure elucidation of unknown volatile and semi-volatile organic compounds. Gas chromatography with high-resolution mass spectrometry quantitative analyses was previously focused on the determination of dioxins and related compounds using magnetic sector type analyzers, a standing requirement of many international standards. The introduction of a quadrupole high-resolution time-of-flight mass analyzer broadened interest in this method and novel applications were developed, especially for multi-target screening purposes. This review is focused on the development and the most interesting applications of gas chromatography coupled to high-resolution mass spectrometry towards analysis of environmental matrices, biological fluids, and food safety since 2010. The main attention is paid to various approaches and applications of gas chromatography coupled to high-resolution mass spectrometry for non-target screening to identify contaminants and to characterize the chemical composition of environmental, food, and biological samples. The most interesting quantitative applications, where a significant contribution of gas chromatography with high-resolution mass spectrometry over the currently used methods is expected, will be discussed as well. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  14. Identification of inorganic anions by gas chromatography/mass spectrometry.

    Science.gov (United States)

    Sakayanagi, Masataka; Yamada, Yaeko; Sakabe, Chikako; Watanabe, Kunio; Harigaya, Yoshihiro

    2006-03-10

    Inorganic anions were identified by using gas chromatography/mass spectrometry (GC/MS). Derivatization of the anions was achieved with pentafluorobenzyl p-toluenesulphonate (PFB-Tos) as the reaction reagent and a crown ether as a phase transfer catalyst. When PFB-Br was used as the reaction reagent, the retention time of it was close to those of the derivatized inorganic anions and interfered with the analysis. In contrast, the retention time of PFB-Tos differed greatly from the PFB derivatives of the inorganic anions and the compounds of interest could be detected without interference. Although the PFB derivatives of SO4, S2O3, CO3, ClO4, and ClO3 could not be detected, the derivatives of F, Cl, Br, I, CN, OCN, SCN, N3, NO3, and NO2 were detected using PFB-Tos as the derivatizing reagent. The inorganic anions were detectable within 30 ng approximately, which is of sufficient sensitivity for use in forensic chemistry. Accurate mass number was measured for each PFB derivative by high-resolution mass spectrometry (HRMS) within a measurement error of 2 millimass units (mmu), which allowed determination of the compositional formula from the mass number. In addition, actual analysis was performed successively by our method using trial samples of matrix.

  15. Characterization of aldolase from Methanococcus jannaschii by gas chromatography.

    Science.gov (United States)

    Nam Shin, Jeong E; Kim, Mi-Jung; Choi, Ji-ah; Chun, Keun Ho

    2007-09-30

    The products of reactions catalyzed by Methanococcus. jannaschii (Mj) aldolase using various substrates were identified by gas chromatography (GC). Although Mj aldolase is considered a fuculose-1-phosphate aldolase based on homology searching after gene sequencing, it has not been proven to be a fuculose-1-phosphate aldolase based on its reaction products. Mj aldolase was found to catalyze reactions between glycoaldehyde or D, L-glyceraldehyde and DHAP (dihydroxyacetone phosphate). Before performing GC the ketoses produced were converted into peracetylated alditol derivatives by sequential reactions, i.e., dephosphorylation, NaBH(4) reduction, and acetylation. By comparing the GC data of final products with those of standard alditol samples, it was found that the enzymatic reactions with glycoaldehyde, D-glyceraldehyde, and D, L-glyceraldehyde produced D-ribulose-1-phosphate, D-psicose-1-phosphate, and a mixture of D-psicose and L-tagatose-1-phosphate, respectively. These results provide direct evidence that Mj aldolase is a fuculose-1-phosphate aldolase.

  16. Electronic Nose using Gas Chromatography Column and Quartz Crystal Microbalance

    Directory of Open Access Journals (Sweden)

    Hari Agus Sujono

    2011-08-01

    Full Text Available The conventional electronic nose usually consists of an array of dissimilar chemical sensors such as quartz crystal microbalance (QCM combined with pattern recognition algorithm such as Neural network. Because of parallel processing, the system needs a huge number of sensors and circuits which may emerge complexity and inter-channel crosstalk problems. In this research, a new type of odor identification which combines between gas chromatography (GC and electronic nose methods has been developed. The system consists of a GC column and a 10-MHz quartz crystal microbalance sensor producing a unique pattern for an odor in time domain. This method offers advantages of substantially reduced size, interferences and power consumption in comparison to existing odor identification system. Several odors of organic compounds were introduced to evaluate the selectivity of the system. Principle component analysis method was used to visualize the classification of each odor in two-dimensional space. This system could resolve common organic solvents, including molecules of different classes (aromatic from alcohols as well as those within a particular class (methanol from ethanol and also fuels (premium from pertamax. The neural network can be taught to recognize the odors tested in the experiment with identification rate of 85 %. It is therefore the system may take the place of human nose, especially for poisonous odor evaluations.

  17. Reducing Motional Decoherence in Ion Traps with Surface Science Methods

    Science.gov (United States)

    Haeffner, Hartmut

    2014-03-01

    Many trapped ions experiments ask for low motional heating rates while trapping the ions close to trapping electrodes. However, in practice small ion-electrode distances lead to unexpected high heating rates. While the mechanisms for the heating is still unclear, it is now evident that surface contamination of the metallic electrodes is at least partially responsible for the elevated heating rates. I will discuss heating rate measurements in a microfabricated surface trap complemented with basic surface science studies. We monitor the elemental surface composition of the Cu-Al alloy trap with an Auger spectrometer. After bake-out, we find a strong Carbon and Oxygen contamination and heating rates of 200 quanta/s at 1 MHz trap frequency. After removing most of the Carbon and Oxygen with Ar-Ion sputtering, the heating rates drop to 4 quanta/s. Interestingly, we still measure the decreased heating rate even after the surface oxidized from the background gas throughout a 40-day waiting time in UHV.

  18. Using Metal Complex Ion-Molecule Reactions in a Miniature Rectilinear Ion Trap Mass Spectrometer to Detect Chemical Warfare Agents

    Science.gov (United States)

    Graichen, Adam M.; Vachet, Richard W.

    2013-06-01

    The gas-phase reactions of a series of coordinatively unsaturated [Ni(L)n]y+ complexes, where L is a nitrogen-containing ligand, with chemical warfare agent (CWA) simulants in a miniature rectilinear ion trap mass spectrometer were investigated as part of a new approach to detect CWAs. Results show that upon entering the vacuum system via a poly(dimethylsiloxane) (PDMS) membrane introduction, low concentrations of several CWA simulants, including dipropyl sulfide (simulant for mustard gas), acetonitrile (simulant for the nerve agent tabun), and diethyl phosphite (simulant for nerve agents sarin, soman, tabun, and VX), can react with metal complex ions generated by electrospray ionization (ESI), thereby providing a sensitive means of detecting these compounds. The [Ni(L)n]2+ complexes are found to be particularly reactive with the simulants of mustard gas and tabun, allowing their detection at low parts-per-billion (ppb) levels. These detection limits are well below reported exposure limits for these CWAs, which indicates the applicability of this new approach, and are about two orders of magnitude lower than electron ionization detection limits on the same mass spectrometer. The use of coordinatively unsaturated metal complexes as reagent ions offers the possibility of further tuning the ion-molecule chemistry so that desired compounds can be detected selectively or at even lower concentrations.

  19. Automated determination of aliphatic primary amines in wastewater by simultaneous derivatization and headspace solid-phase microextraction followed by gas chromatography-tandem mass spectrometry.

    Science.gov (United States)

    Llop, Anna; Pocurull, Eva; Borrull, Francesc

    2010-01-22

    This paper presents a fully automated method for determining ten primary amines in wastewater at ng/L levels. The method is based on simultaneous derivatization with pentafluorobenzaldehyde (PFBAY) and headspace solid-phase microextraction (HS-SPME) followed by gas chromatography coupled to ion trap tandem mass spectrometry (GC-IT-MS-MS). The influence of main factors on the efficiency of derivatization and of HS-SPME is described in detail and optimized by a central composite design. For all species, the highest enrichment factors were achieved using a 85 microm polyacrylate (PA) fiber exposed in the headspace of stirred water samples (750 rpm) at pH 12, containing 360 g/L of NaCl, at 40 degrees C for 15 min. Under optimized conditions, the proposed method achieved detection limits ranging from 10 to 100 ng/L (except for cyclohexylamine). The optimized method was then used to determine the presence of primary amines in various types of wastewater samples, such as influent and effluent wastewater from municipal and industrial wastewater treatment plants (WWTPs) and a potable water treatment plant. Although the analysis of these samples revealed the presence of up to 1500 microg/L of certain primary amines in influent industrial wastewater, the concentration of these compounds in the effluent and in municipal and potable water was substantially lower, at low microg/L levels. The new derivatization-HS-SPME-GC-IT-MS-MS method is suitable for the fast, reliable and inexpensive determination of primary amines in wastewater in an automated procedure. Copyright 2009 Elsevier B.V. All rights reserved.

  20. Development of a multiplexed interface for capillary electrophoresis-electrospray ion trap mass spectrometry.

    Science.gov (United States)

    Li, Fu-An; Wu, Ming-Chi; Her, Guor-Rong

    2006-08-01

    A four-channel multiplexed electrospray capillary electrophoresis interface has been developed. This new interface permits up to four capillary electrophoresis columns to be sampled sequentially by means of a stepper motor and a notched rotating plate assembly, which at any instant occludes all but a single sprayer. In this design, four sheath liquid electrospray probes are oriented in a circular array situated 90 degrees relative to one another. The rotating metal disk, which contains a one-quarter notch, is mounted to the stepper motor assembly and is located between the sprayers and the entrance aperture of an ion trap mass spectrometer. By using the data acquisition signal from the ion trap mass spectrometer, the scan event is synchronized with the rotation of the metal disk. With this device, four discrete sample streams can be simultaneously analyzed, resulting in a 4-fold increase in analytical throughput.

  1. Ion Trapping, Storage, and Ejection in Structures for Lossless Ion Manipulations.

    Science.gov (United States)

    Zhang, Xinyu; Garimella, Sandilya V B; Prost, Spencer A; Webb, Ian K; Chen, Tsung-Chi; Tang, Keqi; Tolmachev, Aleksey V; Norheim, Randolph V; Baker, Erin S; Anderson, Gordon A; Ibrahim, Yehia M; Smith, Richard D

    2015-06-16

    A new Structures for Lossless Ion Manipulations (SLIM) module, having electrode arrays patterned on a pair of parallel printed circuit boards (PCB), was constructed and utilized to investigate capabilities for ion trapping at a pressure of 4 Torr. Positive ions were confined by application of RF voltages to a series of inner rung electrodes with alternating phase on adjacent electrodes, in conjunction with positive DC potentials on surrounding guard electrodes on each PCB. An axial DC field was also introduced by stepwise varying the DC potentials applied to the inner rung electrodes to control the ion transport and accumulation inside the ion trapping region. We show that ions can be trapped and accumulated with up to 100% efficiency, stored for at least 5 h with no significant losses, and then could be rapidly ejected from the SLIM trap. The present results provide a foundation for the development of much more complex SLIM devices that facilitate extended ion manipulations.

  2. Determination of basic azaarenes and polynuclear aromatic hydrocarbons in airborne particulate matter by gas chromatography

    DEFF Research Database (Denmark)

    Nielsen, Torben; Clausen, Peraxel; Jensen, Finn Palmgren

    1986-01-01

    phase (adjusted to pH 14 with potassium hydroxide) with dichloromethane, and determined by capillary gas chromatography (g.c.) with a nitrogen-sensitive detector. The PAH in the toluene phase are isolated by means of semipreparative high-performance liquid chromatography and liquid-liquid extraction...

  3. Investigation of surface properties of physico-chemically modified natural fibres using inverse gas chromatography

    CSIR Research Space (South Africa)

    Cordeiro, N

    2011-01-01

    Full Text Available Inverse gas chromatography (IGC) is a suitable method to determine surface energy of natural fibres when compared to wetting techniques. In the present study, the surface properties of raw and modified lignocellulosic fibres have been investigated...

  4. Analysis of chemical signals in red fire ants by gas chromatography and pattern recognition techniques

    Science.gov (United States)

    The combination of gas chromatography and pattern recognition (GC/PR) analysis is a powerful tool for investigating complicated biological problems. Clustering, mapping, discriminant development, etc. are necessary to analyze realistically large chromatographic data sets and to seek meaningful relat...

  5. ENVIRONMENTAL ANALYSIS BY AB INITIO QUANTUM MECHANICAL COMPUTATION AND GAS CHROMATOGRAPHY/FOURIER TRANSFORM INFRARED SPECTROMETRY.

    Science.gov (United States)

    Computational chemistry, in conjunction with gas chromatography/mass spectrometry/Fourier transform infrared spectrometry (GC/MS/FT-IR), was used to tentatively identify seven tetrachlorobutadiene (TCBD) isomers detected in an environmental sample. Computation of the TCBD infrare...

  6. Accelerated solvent extraction followed by on-line solid-phase extraction coupled to ion trap LC/MS/MS for analysis of benzalkonium chlorides in sediment samples

    Science.gov (United States)

    Ferrer, I.; Furlong, E.T.

    2002-01-01

    Benzalkonium chlorides (BACs) were successfully extracted from sediment samples using a new methodology based on accelerated solvent extraction (ASE) followed by an on-line cleanup step. The BACs were detected by liquid chromatography/ion trap mass spectrometry (LC/MS) or tandem mass spectrometry (MS/MS) using an electrospray interface operated in the positive ion mode. This methodology combines the high efficiency of extraction provided by a pressurized fluid and the high sensitivity offered by the ion trap MS/MS. The effects of solvent type and ASE operational variables, such as temperature and pressure, were evaluated. After optimization, a mixture of acetonitrile/water (6:4 or 7:3) was found to be most efficient for extracting BACs from the sediment samples. Extraction recoveries ranged from 95 to 105% for C12 and C14 homologues, respectively. Total method recoveries from fortified sediment samples, using a cleanup step followed by ASE, were 85% for C12BAC and 79% for C14-BAC. The methodology developed in this work provides detection limits in the subnanogram per gram range. Concentrations of BAC homologues ranged from 22 to 206 ??g/kg in sediment samples from different river sites downstream from wastewater treatment plants. The high affinity of BACs for soil suggests that BACs preferentially concentrate in sediment rather than in water.

  7. Quantitative determination of organochlorine pesticides in sewage sludges using soxtec, soxhlet and pressurized liquid extractions and ion trap mass-mass spectrometric detection.

    Science.gov (United States)

    Helaleh, M I H; Al-Omair, A; Ahmed, N; Gevao, B

    2005-06-01

    A new analytical method is described for the determination of organochlorine pesticides (OCPs) in sewage sludges using GC-ion trap-MS-MS. In this work, 16 organo-chlorine pesticides (OCPs) listed by the US Environmental Protection Agency (US EPA) as priority pollutants were separated and quantified. Sludge samples from three of Kuwait's wastewater treatment plants (WWTPs) were analyzed for organochlorine pesticides (OCPs). Spiked sludge samples were extracted with a mixture of (1:1 v/v) dichloromethane (DCM)/hexane. The extracts were cleaned on a silica/aluminum oxide column, then transferred to a gel permeation chromatography (GPC) column, before undergoing further silica/aluminum oxide clean-up; the presence of OCPs was then confirmed by GC-ion trap-MS-MS. Three extraction techniques, soxtec, soxhlet, and pressurized liquid extractions were utilized, compared and validated using the spiked sludge samples. The methods were validated in term of accuracy (recovery) and precision (RSD). The method recovery values varied from 76.1 to 92.9% for the three extraction techniques.

  8. Evaporative cooling of highly charged ions in EBIT [Electron Beam Ion Trap]: An experimental realization

    International Nuclear Information System (INIS)

    Schneider, M.B.; Levine, M.A.; Bennett, C.L.; Henderson, J.R.; Knapp, D.A.; Marrs, R.E.

    1988-01-01

    Both the total number and trapping lifetime of near-neon-like gold ions held in an electron beam ion trap have been greatly increased by a process of 'evaporative cooling'. A continuous flow of low-charge-state ions into the trap cools the high-charge-state ions in the trap. Preliminary experimental results using titanium ions as a coolant are presented. 8 refs., 6 figs., 2 tabs

  9. Mathematical Modeling of Resonant Processes in Confined Geometry of Atomic and Atom-Ion Traps

    Directory of Open Access Journals (Sweden)

    Melezhik Vladimir S.

    2018-01-01

    Full Text Available We discuss computational aspects of the developed mathematical models for resonant processes in confined geometry of atomic and atom-ion traps. The main attention is paid to formulation in the nondirect product discrete-variable representation (npDVR of the multichannel scattering problem with nonseparable angular part in confining traps as the boundary-value problem. Computational efficiency of this approach is demonstrated in application to atomic and atom-ion confinement-induced resonances we predicted recently.

  10. Calibration procedure for secular frequency scanning in ion trap mass spectrometers.

    Science.gov (United States)

    Snyder, Dalton T; Pulliam, Christopher J; Cooks, R Graham

    2016-05-30

    Mass spectra can be recorded using ion traps by scanning the frequency of an alternating current (ac) signal that corresponds to the secular frequency of a trapped ion. There is a considerable simplification in the instrumentation needed to perform such a scan compared with conventional scans of the radiofrequency (rf) amplitude. However, mass calibration is difficult. An algorithm that can be used to achieve mass calibration is investigated and the factors that affect ion mass assignments are discussed. Time domain data, recorded using a commercial benchtop linear ion trap mass spectrometer, are converted to the m/z domain using ion Mathieu parameter q u values which are derived from the dimensionless frequency parameter β u expressed as a continuing fraction in terms of q u . The relationship between the operating parameters of an ideal ion trap and the ion m/z ratio is derived from the Mathieu equations and expressed as an algorithm which through successive approximations yields the Mathieu q u value and hence m/z values and peak widths. The predictions of the algorithm are tested against experiment by sweeping the frequency of a small supplementary ac signal so as to cause mass-selective ejection of trapped ions. Calibration accuracy is always better than 0.1%, often much better. Peak widths correspond to a mass resolution of 250 to 500 in the m/z 100-1800 range in secular frequency scans. A simple, effective method of calibration of mass spectra recorded using secular frequency scans is achieved. The effects of rf amplitude, scan rate, and ac amplitude on calibration parameters are shown using LTQ linear ion trap data. Corrections for differences in ion mass must be made for accurate calibration, and this is easily incorporated into the calibration procedure. Copyright © 2016 John Wiley & Sons, Ltd. Copyright © 2016 John Wiley & Sons, Ltd.

  11. Mathematical Modeling of Resonant Processes in Confined Geometry of Atomic and Atom-Ion Traps

    Science.gov (United States)

    Melezhik, Vladimir S.

    2018-02-01

    We discuss computational aspects of the developed mathematical models for resonant processes in confined geometry of atomic and atom-ion traps. The main attention is paid to formulation in the nondirect product discrete-variable representation (npDVR) of the multichannel scattering problem with nonseparable angular part in confining traps as the boundary-value problem. Computational efficiency of this approach is demonstrated in application to atomic and atom-ion confinement-induced resonances we predicted recently.

  12. Detection of Chemical/Biological Agents and Stimulants using Quadrupole Ion Trap Mass Spectrometry

    International Nuclear Information System (INIS)

    Harmon, S.H.; Hart, K.J.; Vass, A.A.; Wise, M.B.; Wolf, D.A.

    1999-01-01

    expanded with additional bacteria and fungi. These spectra were acquired on a Finnigan Magnum ion trap using helium buffer gas. A new database of Cl spectra of microorganisms is planned using the CBMS Block II instrument and air as the buffer gas. Using the current database, the fatty acid composition of the organisms was compared using the percentage of the ion current attributable to fatty acids. The data presented suggest promising rules for discrimination of these organisms. Strain, growth media and vegetative state do contribute to some of the distributions observed in the data. However, the data distributions observed in the current study only reflect our experience to date and do not fully represent the variability that might be expected in practice: Acquisition of MS/ MS spectra has begun (using He and air buffer gas) of the protonated molecular ion of a variety of fatty acids and for a number of ions nominally assigned as fatty acids from microorganisms. These spectra will be used to help verify fatty acid

  13. Enantioselective determination of triazole fungicide simeconazole in vegetables, fruits, and cereals using modified QuEChERS (quick, easy, cheap, effective, rugged and safe) coupled to gas chromatography/tandem mass spectrometry.

    Science.gov (United States)

    Li, Jing; Dong, Fengshou; Xu, Jun; Liu, Xingang; Li, Yuanbo; Shan, Weili; Zheng, Yongquan

    2011-09-19

    A rapid and effective method for enantioselective determination of simeconazole enantiomers in food products (cucumber, tomato, apple, pear, wheat and rice) has been developed. The enantiomers were resolved by capillary gas chromatography (GC) using a commercial chiral column (BGB-172) and a temperature program from 150°C (held for 1 min) and then raised at 10°C min(-1) to 240°C (held for 10 min). This enantioselective gas chromatographic separation was combined with a clean-up/enrichment procedure based on the modification of QuEChERS (quick, easy, cheap, effective, rugged and safe) method. Co-extractives were removed with graphitized carbon black/primary secondary amine (GCB/PSA) solid-phase extraction (SPE) cartridges using acetonitrile:toluene (3:1, v/v) as eluent. Gas chromatography/ion trap mass spectrometry (GC-ITMS) with electron ionization (EI) was then used for qualitative and quantitative determination of the simeconazole enantiomers. Two precursor-to-product ion transitions (m/z 121-101 and 195-153) with the best signal intensity were chosen to build the multiple-reaction monitoring (MRM) acquisition method. The limits of detection for each enantiomer of simeconazole in six food products ranged between 0.4 and 0.9 μg kg(-1), which were much lower than maximum residue levels (MRLs) established by Japan. The methodology was successfully applied for the enantioselective analysis of simeconazole enantiomers in real samples, indicating its efficacy in investigating the environmental stereochemistry of simeconazole in food matrix. Copyright © 2011 Elsevier B.V. All rights reserved.

  14. The on-line charge breeding program at TRIUMF's Ion Trap For Atomic and Nuclear Science for precision mass measurements.

    Science.gov (United States)

    Simon, M C; Bale, J C; Chowdhury, U; Eberhardt, B; Ettenauer, S; Gallant, A T; Jang, F; Lennarz, A; Luichtl, M; Ma, T; Robertson, D; Simon, V V; Andreoiu, C; Brodeur, M; Brunner, T; Chaudhuri, A; Crespo López-Urrutia, J R; Delheij, P; Frekers, D; Grossheim, A; Gwinner, G; Kwiatkowski, A A; Lapierre, A; Mané, E; Pearson, M R; Ringle, R; Schultz, B E; Dilling, J

    2012-02-01

    TRIUMF's Ion Trap for Atomic and Nuclear science (TITAN) constitutes the only high precision mass measurement setup coupled to a rare isotope facility capable of increasing the charge state of short-lived nuclides prior to the actual mass determination in a Penning trap. Recent developments around TITAN's charge breeder, the electron beam ion trap, form the basis for several successful experiments on radioactive isotopes with half-lives as low as 65 ms and in charge states as high as 22+.

  15. Doping control analysis of anabolic steroids in equine urine by gas chromatography-tandem mass spectrometry.

    Science.gov (United States)

    Wong, April S Y; Leung, Gary N W; Leung, David K K; Wan, Terence S M

    2017-09-01

    Anabolic steroids are banned substances in equine sports. Gas chromatography-mass spectrometry (GC-MS) has been the traditional technique for doping control analysis of anabolic steroids in biological samples. Although liquid chromatography-mass spectrometry (LC/MS) has become an important technique in doping control, the detection of saturated hydroxysteroids by LC-MS remains a problem due to their low ionization efficiency under electrospray. The recent development in fast-scanning gas-chromatography-triple-quadrupole mass spectrometry (GC-MS/MS) has provided a better alternative with a significant reduction in chemical noise by means of selective reaction monitoring. Herein, we present a sensitive and selective method for the screening of over 50 anabolic steroids in equine urine using gas chromatography-tandem mass spectrometry (GC-MS/MS). Copyright © 2016 John Wiley & Sons, Ltd. Copyright © 2016 John Wiley & Sons, Ltd.

  16. Applications of the gas chromatography in the nuclear science and technology

    International Nuclear Information System (INIS)

    Gasco Sanchez, L.

    1972-01-01

    This paper is a review on the applications of the gas chromatography in the nuclear science and technology published up to December 1971. Its contents has been classified under the following heads; I) Radiogaschromatography, II) Isotope separation, III) Preparation of labelled molecules, IV) Nuclear fuel cycle, V) Nuclear reactor technology, VI) Irradiation chemistry, VIl) Separation of me tal compounds in gas phase, VIII) Applications of the gas chromatography carried out at the Junta de Energia Nuclear, Spain. Arapter VIII only includes the investigations carried out from January 1969 to December 1971. Previous investigations in this field has been published elsewhere. (Author)

  17. Fast Sampling Gas Chromatography (GC) System for Speciation in a Shock Tube

    Science.gov (United States)

    2016-10-31

    has four analytical columns, which allow for the precise measurement of permanent gases (e.g. O2, N2, CO, CO2, CH4), clear separation (and therefore...Unlimited UU UU UU UU 10-11-2016 1-Aug-2015 31-Jul-2016 Final Report: Fast-Sampling Gas Chromatography (GC) System for Speciation in a Shock Tube The...Office P.O. Box 12211 Research Triangle Park, NC 27709-2211 Gas sampling, shock tube, jet fuel, gas chromatography REPORT DOCUMENTATION PAGE 11

  18. Multiplex gas chromatography: an alternative concept for gas chromatographic analysis of planetary atmospheres

    Science.gov (United States)

    Valentin, J. R.

    1989-01-01

    Gas chromatography (GC) is a powerful technique for analyzing gaseous mixtures. Applied to the earth's atmosphere, GC can be used to determine the permanent gases--such as carbon dioxide, nitrogen, and oxygen--and to analyze organic pollutants in air. The U.S. National Aeronautics and Space Administration (NASA) has used GC in spacecraft missions to Mars (the Viking Biology Gas Exchange Experiment [GEX] and the Viking Gas Chromatograph-Mass Spectrometer [GC-MS]) and to Venus (the Pioneer Venus Gas Chromatograph [PVGC] on board the Pioneer Venus sounder probe) for determining the atmospheric constituents of these two planets. Even though conventional GC was very useful in the Viking and Pioneer missions, spacecraft constraints and limitations intrinsic to the technique prevented the collection of more samples. With the Venus probe, for instance, each measurement took a relatively long time to complete (10 min), and successive samples could not be introduced until the previous samples had left the column. Therefore, while the probe descended through the Venusian atmosphere, only three samples were acquired at widely separated altitudes. With the Viking mission, the sampling rate was not a serious problem because samples were acquired over a period of one year. However, the detection limit was a major disadvantage. The GC-MS could not detect simple hydrocarbons and simple alcohols below 0.1 ppm, and the GEX could not detect them below 1 ppm. For more complex molecules, the detection limits were at the parts-per-billion level for both instruments. Finally, in both the Viking and Pioneer missions, the relatively slow rate of data acquisition limited the number of analyses, and consequently, the amount of information returned. Similar constraints are expected in future NASA missions. For instance, gas chromatographic instrumentation is being developed to collect and analyze organic gases and aerosols in the atmosphere of Titan (one of Saturn's satellites). The Titan

  19. Foetal Fentanyl Exposure and Ion Trapping after Intravenous and Transdermal Administration to the Ewe.

    Science.gov (United States)

    Heikkinen, Emma M; Kokki, Hannu; Heikkinen, Aki; Ranta, Veli-Pekka; Räsänen, Juha; Voipio, Hanna-Marja; Kokki, Merja

    2017-02-01

    Opioids given to pregnant and parturient women are relatively freely transferred across the placenta. Spinal, epidural and intravenous fentanyl has been studied in pregnant women and neonates, but foetal safety of fentanyl dosing with transdermal patch during pregnancy and labour is not sufficiently studied. Foetal pH is physiologically lower than maternal pH, and thus, opioids, which are weak bases, are ionized and may cumulate to foetus. Foetal asphyxia may further worsen acidosis, and ion trapping induced by low pH is assumed to increase the foetal exposure to opioids. Here, we show that no correlation between foetal acidosis and ion trapping of fentanyl could be found. In three experiments, 29 pregnant sheep were administered fentanyl with 2 μg/kg/h patch supplemented with IV boluses/infusion. Foetal exposure to fentanyl was extensive, median 0.34 ng/ml (quartiles 0.21, 0.42), yet drug accumulation to foetus was not observed, and median of foetal/maternal concentration (F/M) ratio was 0.63 (0.43, 0.75) during the first hours after the fentanyl administration. Low foetal pH and pH difference between ewe and the foetus did not correlate with fentanyl concentration in the foetus or F/M ratio. At steady-state during the second patch worn, foetal plasma fentanyl was low, 0.13 ng/ml, and the median of F/M ratio was 0.69. Our results demonstrate that drug accumulation to foetus caused by ion trapping seen with some weak base opioids may not be that significant with fentanyl. These results have a clinical relevance when fentanyl is dosed to pregnant woman and the foetus is acidemic. © 2016 Nordic Association for the Publication of BCPT (former Nordic Pharmacological Society).

  20. High-resolution excitation of ions in a low-pressure linear ion trap.

    Science.gov (United States)

    Collings, B A

    2011-01-15

    An exploration of the parameters necessary to obtain high-resolution excitation, using dipolar excitation, of an ion in a linear ion trap has been undertaken in this study. These parameters included ion trap pressure, excitation amplitude, excitation period, drive frequency of the ion trap, Mathieu q value and the mass of the ion of interest. An understanding of how these parameters play a role in high-resolution excitation is necessary to the development of a method for the targeted tandem mass spectrometric (MS/MS) analysis of ions with the same nominal mass. Resonance excitation profiles with full width half maxima as narrow as 0.015 m/z units could be obtained, under the right conditions, for an ion from a homogenously substituted triazatriphosphorine at m/z 322.049, which translates into a mass resolution of >21 500. In this particular case the requirement for high resolution was a low trap pressure (3.8 × 10(-5) Torr), low excitation amplitude (3 mV), long excitation period (100 ms) and a high Mathieu q value(0.8) when using a drive frequency of 1.228 MHz. Similar conditions were used to demonstrate the isolation of individual [M + H](+) component ions from mixtures of bromazepam (m/z 316.008)/chlorprothixene (m/z 316.0921)/fendiline (m/z 316.206) and chlorprothixene (m/z 316.0921)/oxycodone (m/z 316.1543)/fendiline (m/z 316.206) prior to obtaining product ion spectra with excitation at q = 0.236. In the former mixture the individual components were isolated with near 100% efficiency while in the latter mixture the isolation efficiency dropped to near 50% for the oxycodone component and to 80% for the other components. Copyright © 2010 John Wiley & Sons, Ltd.

  1. Impact of comprehensive two-dimensional gas chromatography with mass spectrometry on food analysis.

    Science.gov (United States)

    Tranchida, Peter Q; Purcaro, Giorgia; Maimone, Mariarosa; Mondello, Luigi

    2016-01-01

    Comprehensive two-dimensional gas chromatography with mass spectrometry has been on the separation-science scene for about 15 years. This three-dimensional method has made a great positive impact on various fields of research, and among these that related to food analysis is certainly at the forefront. The present critical review is based on the use of comprehensive two-dimensional gas chromatography with mass spectrometry in the untargeted (general qualitative profiling and fingerprinting) and targeted analysis of food volatiles; attention is focused not only on its potential in such applications, but also on how recent advances in comprehensive two-dimensional gas chromatography with mass spectrometry will potentially be important for food analysis. Additionally, emphasis is devoted to the many instances in which straightforward gas chromatography with mass spectrometry is a sufficiently-powerful analytical tool. Finally, possible future scenarios in the comprehensive two-dimensional gas chromatography with mass spectrometry food analysis field are discussed. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  2. Single Qubit Manipulation in a Microfabricated Surface Electrode Ion Trap (Open Access, Publisher’s Version)

    Science.gov (United States)

    2013-09-13

    electrode ion trap with field compensation using a modulated Raman effect D T C Allcock, J A Sherman, D N Stacey et al. Spatially uniform single-qubit gate...in thermal states of motion G Kirchmair, J Benhelm, F Zähringer et al. Normal modes of trapped ions in the presence of anharmonic trap potentials J P...Qloaded = 280) [35]. New Journal of Physics 15 (2013) 093018 (http://www.njp.org/) 5 2.1 GHz Zeeman = 1.4 MHz/G 36 9. 5 nm HF = 12.6 GHz 171Yb+ 2P 1

  3. Cooling of ions trapped in potential wells produced by electromagnetic radiation fields

    International Nuclear Information System (INIS)

    Sobehart, J.R.

    1990-01-01

    The probability distributions for the ground state and the excited state of a two-level ion trapped in an harmonic potential well are studied. The ion is excited by electromagnetic radiation and relaxes back due to either spontaneous or stimulated emission. The photon statistics is considered Poissonian and the momentum transfer between the electromagnetic field and the ion is assumed discrete. The present results are closely related to the quantum treatment in the heavy particle limit as well as to those derived from previous semiclassical models. (Author) [es

  4. Recent trends in precision measurements of atomic and nuclear properties with lasers and ion traps

    Energy Technology Data Exchange (ETDEWEB)

    Block, Michael, E-mail: m.block@gsi.de [GSI Helmholtzzentrum für Schwerionenforschung GmbH (Germany)

    2017-11-15

    The X. international workshop on “Application of Lasers and Storage Devices in Atomic Nuclei Research” took place in Poznan in May 2016. It addressed the latest experimental and theoretical achievements in laser and ion trap-based investigations of radionuclides, highly charged ions and antiprotons. The precise determination of atomic and nuclear properties provides a stringent benchmark for theoretical models and eventually leads to a better understanding of the underlying fundamental interactions and symmetries. This article addresses some general trends in this field and highlights select recent achievements presented at the workshop. Many of these are covered in more detail within the individual contributions to this special issue of Hyperfine Interactions.

  5. Recent trends in precision measurements of atomic and nuclear properties with lasers and ion traps

    Science.gov (United States)

    Block, Michael

    2017-11-01

    The X. international workshop on "Application of Lasers and Storage Devices in Atomic Nuclei Research" took place in Poznan in May 2016. It addressed the latest experimental and theoretical achievements in laser and ion trap-based investigations of radionuclides, highly charged ions and antiprotons. The precise determination of atomic and nuclear properties provides a stringent benchmark for theoretical models and eventually leads to a better understanding of the underlying fundamental interactions and symmetries. This article addresses some general trends in this field and highlights select recent achievements presented at the workshop. Many of these are covered in more detail within the individual contributions to this special issue of Hyperfine Interactions.

  6. Community air monitoring for pesticides-part 2: multiresidue determination of pesticides in air by gas chromatography, gas chromatography-mass spectrometry, and liquid chromatography-mass spectrometry.

    Science.gov (United States)

    Hengel, Matt; Lee, P

    2014-03-01

    Two multiresidue methods were developed to determine pesticides in air collected in California. Pesticides were trapped using XAD-4 resin and extracted with ethyl acetate. Based on an analytical method from the University of California Davis Trace Analytical Laboratory, pesticides were detected by analyzing the extract by gas chromatography-mass spectrometry (GC-MS) to determine chlorothalonil, chlorthal-dimethyl, cycloate, dicloran, dicofol, EPTC, ethalfluralin, iprodione, mefenoxam, metolachlor, PCNB, permethrin, pronamide, simazine, trifluralin, and vinclozolin. A GC with a flame photometric detector was used to determine chlorpyrifos, chlorpyrifos oxon, diazinon, diazinon oxon, dimethoate, dimethoate oxon, fonophos, fonophos oxon, malathion, malathion oxon, naled, and oxydemeton. Trapping efficiencies ranged from 78 to 92 % for low level (0.5 μg) and 37-104 % for high level (50 and 100 μg) recoveries. Little to no degradation of compounds occurred over 31 days; recoveries ranged from 78 to 113 %. In the California Department of Food and Agriculture (CDFA) method, pesticides were detected by analyzing the extract by GC-MS to determine chlorothalonil, chlorpyrifos, cypermethrin, dichlorvos, dicofol, endosulfan 1, endosulfan sulfate, oxyfluorfen, permethrin, propargite, and trifluralin. A liquid chromatograph coupled to a MS was used to determine azinphos-methyl, chloropyrifos oxon, DEF, diazinon, diazinon oxon, dimethoate, dimethoate oxon, diuron, EPTC, malathion, malathion oxon, metolachlor, molinate, norflurazon, oryzalin, phosmet, propanil, simazine and thiobencarb. Trapping efficiencies for compounds determined by the CDFA method ranged from 10 to 113, 22 to 114, and 56 to 132 % for 10, 5, and 2 μg spikes, respectively. Storage tests yielded 70-170 % recovery for up to 28 days. These multiresidue methods represent flexible, sensitive, accurate, and cost-effective ways to determine residues of various pesticides in ambient air.

  7. Identification of bound alcohols in soil humic acids by gas chromatography-mass spectrometry

    OpenAIRE

    Berthier , Gersende; Dou , Sen; Peakman , Torren; Lichtfouse , Eric

    2000-01-01

    International audience; Humic acids are complex, partly macromolecular, yellow-brownish substances occurring in soils, waters and sediments. In order to shed some light on their molecular structure, crop humic acids were cleaved by alkaline hydrolysis (KOH). The products were fractionated by thin layer chromatography to give mono-alcohols which were analysed as acetate derivatives by gas chromatography coupled to mass spectrometry. Linear alcohols, sterols, stanols and plant-derived triterpen...

  8. Characterization of odor-active compounds of various Chrysanthemum essential oils by gas chromatography-olfactometry, gas chromatography-mass spectrometry and their correlation with sensory attributes.

    Science.gov (United States)

    Xiao, Zuobing; Fan, Binbin; Niu, Yunwei; Wu, Minling; Liu, Junhua; Ma, Shengtao

    2016-01-15

    Volatiles of five kinds of Chrysanthemum essential oils with different manufactures were characterized by descriptive sensory analysis, gas chromatography-olfactometry (GC-O), gas chromatography-mass spectrometry (GC-MS) and statistics analysis. Six sensory attributes (floral, woody, grassy, fruity, sour and minty) were selected to assess Chrysanthemum essential oils. A total of 38 volatile compounds were detected and quantified using standard substances by GC-O and GC-MS. Terpenes constituted the largest chemical group among the volatiles of the essential oils. Then partial least squares regression (PLSR) was used to elucidate the relationship between sensory attributes and aroma compounds. The result showed that α-pinene, β-thujene, α-terpinolen, β-cubebene, caryophyllene, (Z)β-farnesene, (-)-spathulenol, linalool, camphor, camphene, 4-terpineol, Z-citral and 4-isopropyltoluene were typical aroma compounds covaried with characteristic aroma of Chrysanthemum essential oils. Copyright © 2015. Published by Elsevier B.V.

  9. Comparative study of radio gas-chromatography and gas chromatography - mass spectrometry coupling in the identification of metabolites of estrogens and progesterone

    International Nuclear Information System (INIS)

    Adessi, G.; Nhuan, T.Q.; Jayle, M.F.

    1978-01-01

    Radio-gas chromatography (RGC) and gas chromatography-mass spectrometry (GC-MS) were used to identify estrogen and progesterone metabolites. The RGC enables the identification of metabolites of labelled precursors ( 3 H)-estradiol-17β and ( 14 C)-progesterone were used as precursors. The GC-MS analytical technique with mass fragmentography, offers the interest of using unlabelled precursors at physiological levels. The identification of metabolites was based on obtaining the mass spectrum or the compiled fragmentogram on the basis of the most characteristic fragment ions. More over, several metabolites can be quantified on the same fragmentogram. Results on the metabolism of estradiol-17β and progesterone by the hepatic tissue of guinea pigs are given. (Auth.)

  10. Method development and validation for determining 1,3-butadiene in human blood by gas chromatography-mass spectrometry and head-space gas chromatography.

    Science.gov (United States)

    Zhang, Su-Jing; Shen, Bao-Hua; Zhuo, Xian-Yi

    2013-04-01

    To develop a simple, validated method for identifying and quantifying 1,3-butadiene (BD) in human blood by gas chromatography-mass spectrometry (GC-MS) and head-space gas chromatography (HS-GC). BD was identified by GC-MS and HS-GC, and quantified by HS-GC. The method showed that BD had a good linearity from 50 to 500 microg/mL (r > 0.99). The limits of detection and quantification were 10 microg/mL and 50 microg/mL, respectively. Both the intra-day precision and inter-day precision were < 6.08%, and the accuracy was 96.98%-103.81%. The method was applied to an actual case, and the concentration of BD in the case was 242 microg/mL in human blood. This simple method is found to be useful for the routine forensic analysis of acute exposure to BD.

  11. Technology for On-Chip Qubit Control with Microfabricated Surface Ion Traps

    Energy Technology Data Exchange (ETDEWEB)

    Highstrete, Clark [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States). Quantum Information Sciences Dept.; Scott, Sean Michael [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States). RF/Optoelectronics Dept.; Nordquist, Christopher D. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States). RF/Optoelectronics Dept.; Sterk, Jonathan David [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States). Photonic Microsystem Technologies Dept.; Maunz, Peter Lukas Wilhelm [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States). Photonic Microsystem Technologies Dept.; Tigges, Christopher P. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States). Photonic Microsystem Technologies Dept.; Blain, Matthew Glenn [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States). Photonic Microsystem Technologies Dept.; Heller, Edwin J. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States). Microsystems Integration Dept.; Stevens, James E. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States). MESAFab Operations 2 Dept.

    2013-11-01

    Trapped atomic ions are a leading physical system for quantum information processing. However, scalability and operational fidelity remain limiting technical issues often associated with optical qubit control. One promising approach is to develop on-chip microwave electronic control of ion qubits based on the atomic hyperfine interaction. This project developed expertise and capabilities at Sandia toward on-chip electronic qubit control in a scalable architecture. The project developed a foundation of laboratory capabilities, including trapping the 171Yb+ hyperfine ion qubit and developing an experimental microwave coherent control capability. Additionally, the project investigated the integration of microwave device elements with surface ion traps utilizing Sandia’s state-of-the-art MEMS microfabrication processing. This effort culminated in a device design for a multi-purpose ion trap experimental platform for investigating on-chip microwave qubit control, laying the groundwork for further funded R&D to develop on-chip microwave qubit control in an architecture that is suitable to engineering development.

  12. Measurement of Atmospheric Isoprene Concentrations using an Automated Cylindrical Ion Trap Mass Spectrometer

    Science.gov (United States)

    Edwards, G. D.; Shepson, P. B.; Grossenbacher, J. W.; Wells, J. M.; Patterson, G.; Barkett, D. J.

    2005-12-01

    Volatile organic compounds (VOCs) released from the biosphere have been shown to substantially influence both ozone and aerosol chemistry. However, field instruments for the detection of these trace gases are often limited by instrument portability and the ability to distinguish compounds of interest from background or other interfering compounds. We have developed an automated sampling system that is coupled to a lightweight, low power cylindrical ion trap mass spectrometer. This instrument was used for high frequency isoprene measurements at a recent field campaign at the University of Michigan Biological Station PROPHET lab. The inlet uses a sample loop and 6-port valves to trap ambient air samples without the aid of cryogens. VOCs are preconcentrated by sampling directly into a pre-cooled capillary column that is then heated by moving the column to a pre-heated region to obtain rapid separation of isoprene from other species. Isoprene eluting from the end of the column is then introduced to the mass spectrometer. The commercially available cylindrical ion trap (Minotaur 400) interfaced with our preconcentrator yields limits of detection of <80 ppt. The data obtained during the PROPHET 2005 campaign suggest the new inlet system, when coupled with the Minotaur 400 detector provides a feasible field instrument for the fast and accurate evaluation of trace gases over a variety of atmospheric conditions.

  13. Analysis of thermal radiation in ion traps for optical frequency standards

    Science.gov (United States)

    Doležal, M.; Balling, P.; Nisbet-Jones, P. B. R.; King, S. A.; Jones, J. M.; Klein, H. A.; Gill, P.; Lindvall, T.; Wallin, A. E.; Merimaa, M.; Tamm, C.; Sanner, C.; Huntemann, N.; Scharnhorst, N.; Leroux, I. D.; Schmidt, P. O.; Burgermeister, T.; Mehlstäubler, T. E.; Peik, E.

    2015-12-01

    In many of the high-precision optical frequency standards with trapped atoms or ions that are under development to date, the ac Stark shift induced by thermal radiation leads to a major contribution to the systematic uncertainty. We present an analysis of the inhomogeneous thermal environment experienced by ions in various types of ion traps. Finite element models which allow the determination of the temperature of the trap structure and the temperature of the radiation were developed for five ion trap designs, including operational traps at PTB and NPL and further optimized designs. Models were refined based on comparison with infrared camera measurement until an agreement of better than 10% of the measured temperature rise at critical test points was reached. The effective temperature rises of the radiation seen by the ion range from 0.8 K to 2.1 K at standard working conditions. The corresponding fractional frequency shift uncertainties resulting from the uncertainty in temperature are in the 10-18 range for optical clocks based on the Sr+ and Yb+ E2 transitions, and even lower for Yb+ E3, In+ and Al+. Issues critical for heating of the trap structure and its predictability were identified and design recommendations developed.

  14. Characterization of Volatile Compounds from Ethnic Agave Alcoholic Beverages by Gas Chromatography-Mass Spectrometry

    Directory of Open Access Journals (Sweden)

    Pilar Escalante-Minakata

    2008-01-01

    Full Text Available Ethnic Agave alcoholic beverages such as raicilla, sisal, tequila, mezcal, bacanora, sotol and pulque have been analyzed by gas chromatography and headspace solid-phase microextraction- gas chromatography-mass spectrometry (HS-SPME-GC-MS. There were 105 compounds identified, eleven were classified as major compounds and the others were classified as minor compounds. Seventeen minor compounds could be used as authenticity markers since they were beverage specific. Cluster analysis (CA showed that Agave alcoholic beverages could be distinguished by multivariate analysis of major compounds; however, the analysis of minor compounds provided a better fingerprinting.

  15. Simultaneous quantitation of parabens, triclosan, and methyl triclosan in indoor house dust using solid phase extraction and gas chromatography-mass spectrometry.

    Science.gov (United States)

    Fan, Xinghua; Kubwabo, Cariton; Rasmussen, Pat; Jones-Otazo, Heather

    2010-10-06

    An integrated analytical method for the simultaneous determination of five parabens (methyl-, ethyl-, propyl-, butyl-, and benzyl-), triclosan, and methyl triclosan in indoor house dust was developed based on gas chromatographic-mass spectrometric technique (GC/MS). Analytes were extracted from dust samples by sonication. After sample cleanup by solid-phase extraction (SPE), the extracts were derivatized with N-methyl-N-(trimethylsilyl)trifluoroacetamide (MSTFA) and then analyzed by gas chromatography coupled with ion trap mass spectrometry operated in multiple reaction monitoring (MRM) mode. For quantitation, isotope-labelled internal standards were used for each corresponding target analyte. Only 0.05 g of dust sample was needed for the analysis. Method detection limits ranged from 6.5 to 10 ng/g, and absolute recoveries from 74% to 92%. The developed method demonstrated good repeatability and reproducibility, with relative standard deviations (RSDs) less than 16% for all the analytes. The analytes were determined in dust samples collected using two vacuum sampling methods from 63 Canadian homes: a sample of fresh or "active" dust (FD) collected using a Pullman-Holt vacuum sampler, and a composite sample taken from the household vacuum cleaner (HD). Methyl paraben, propyl paraben, and triclosan were detected in all HD and FD samples. HD samples yielded median values for methyl paraben, propyl paraben, and triclosan of 1080, 463, and 378 ng/g, respectively, which were comparable to the FD sample medians of 1120, 618 and 571 ng/g. Ethyl paraben was detected at frequencies of 89% in FD and 73% in HD samples, with median values of 52 and 25 ng/g, respectively. Butyl paraben was detected at frequencies of 44% in FD and 75% in HD samples, with median values of paraben and methyl triclosan were not detected in any of the samples collected by either method. Samples collected according to the fresh dust protocol agreed with the household vacuum samples 90% of the time

  16. Comparison of gas chromatography/isotope ratio mass spectrometry and liquid chromatography/isotope ratio mass spectrometry for carbon stable-isotope analysis of carbohydrates

    NARCIS (Netherlands)

    Moerdijk-Poortvliet, T.C.W.; Schierbeek, H.; Houtekamer, M.; van Engeland, T.; Derrien, D.; Stal, L.J.; Boschker, H.T.S.

    2015-01-01

    Rationale: We compared gas chromatography/isotope ratio mass spectrometry (GC/IRMS) and liquid chromatography/isotope ratio mass spectrometry (LC/IRMS) for the measurement of δ13C values in carbohydrates. Contrary to GC/IRMS, no derivatisation is needed for LC/IRMS analysis of carbohydrates. Hence,

  17. Comparison of gas chromatography/isotope ratio mass spectrometry and liquid chromatography/isotope ratio mass spectrometry for carbon stable-isotope analysis of carbohydrates

    NARCIS (Netherlands)

    Moerdijk-Poortvliet, T.C.W.; Schierbeek, H.; Houtekamer, M.; van Engeland, T.; Derrien, D.; Stal, L.J.; Boschker, H.T.S.

    2015-01-01

    We compared gas chromatography/isotope ratio mass spectrometry (GC/IRMS) and liquid chromatography/isotope ratio mass spectrometry (LC/IRMS) for the measurement of d13C values in carbohydrates. Contrary to GC/IRMS, no derivatisation is needed for LC/IRMS analysis of carbohydrates. Hence, although

  18. Comparison of gas chromatography/isotope ratio mass spectrometry and liquid chromatography/isotope ratio mass spectrometry for carbon stable-isotope analysis of carbohydrates

    NARCIS (Netherlands)

    Moerdijk-Poortvliet, Tanja C. W.; Schierbeek, Henk; Houtekamer, Marco; van Engeland, Tom; Derrien, Delphine; Stal, Lucas J.; Boschker, Henricus T. S.

    2015-01-01

    We compared gas chromatography/isotope ratio mass spectrometry (GC/IRMS) and liquid chromatography/isotope ratio mass spectrometry (LC/IRMS) for the measurement of δ(13)C values in carbohydrates. Contrary to GC/IRMS, no derivatisation is needed for LC/IRMS analysis of carbohydrates. Hence, although

  19. Advancement and application of gas chromatography isotope ratio mass spectrometry techniques for atmospheric trace gas analysis

    Science.gov (United States)

    Giebel, Brian M.

    2011-12-01

    The use of gas chromatography isotope ratio mass spectrometry (GC-IRMS) for compound specific stable isotope analysis is an underutilized technique because of the complexity of the instrumentation and high analytical costs. However stable isotopic data, when coupled with concentration measurements, can provide additional information on a compounds production, transformation, loss, and cycling within the biosphere and atmosphere. A GC-IRMS system was developed to accurately and precisely measure delta13C values for numerous oxygenated volatile organic compounds having natural and anthropogenic sources. The OVOCs include methanol, ethanol, acetone, methyl ethyl ketone, 2-pentanone, and 3-pentanone. Guided by the requirements for analysis of trace components in air, the GC-IRMS system was developed with the goals of increasing sensitivity, reducing dead-volume and peak band broadening, optimizing combustion and water removal, and decreasing the split ratio to the IRMS. The technique relied on a two-stage preconcentration system, a low-volume capillary reactor and water trap, and a balanced reference gas delivery system. Measurements were performed on samples collected from two distinct sources (i.e. biogenic and vehicle emissions) and ambient air collected from downtown Miami and Everglades National Park. However, the instrumentation and the method have the capability to analyze a variety of source and ambient samples. The measured isotopic signatures that were obtained from source and ambient samples provide a new isotopic constraint for atmospheric chemists and can serve as a new way to evaluate their models and budgets for many OVOCs. In almost all cases, OVOCs emitted from fuel combustion were enriched in 13C when compared to the natural emissions of plants. This was particularly true for ethanol gas emitted in vehicle exhaust, which was observed to have a uniquely enriched isotopic signature that was attributed to ethanol's corn origin and use as an alternative

  20. Enantioselective determination of triazole fungicide simeconazole in vegetables, fruits, and cereals using modified QuEChERS (quick, easy, cheap, effective, rugged and safe) coupled to gas chromatography/tandem mass spectrometry

    Energy Technology Data Exchange (ETDEWEB)

    Li Jing, E-mail: lijing2011@gmail.com [Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Key Laboratory of Pesticide Chemistry and Application, Ministry of Agriculture, Beijing, 100193 (China); Dong Fengshou; Xu Jun; Liu Xingang; Li Yuanbo [Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Key Laboratory of Pesticide Chemistry and Application, Ministry of Agriculture, Beijing, 100193 (China); Shan Weili [Institute for the Control of Agrochemicals, Ministry of Agriculture, Beijing 100125 (China); Zheng Yongquan, E-mail: yongquan_zheng@yahoo.com.cn [Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Key Laboratory of Pesticide Chemistry and Application, Ministry of Agriculture, Beijing, 100193 (China)

    2011-09-19

    Highlights: {center_dot} Simeconazole enantiomers were baseline separated by gas chromatography. {center_dot} Optical pure enantiomer was prepared and their elution order was distinguished. {center_dot} Clean-up/enrichment procedure was based on the modification of QuEChERS method. {center_dot} Cleanup step was further improved by solid phase extraction (SPE) technology. {center_dot} Analysis of samples was accomplished by GC-MS/MS. - Abstract: A rapid and effective method for enantioselective determination of simeconazole enantiomers in food products (cucumber, tomato, apple, pear, wheat and rice) has been developed. The enantiomers were resolved by capillary gas chromatography (GC) using a commercial chiral column (BGB-172) and a temperature program from 150 deg. C (held for 1 min) and then raised at 10 deg. C min{sup -1} to 240 deg. C (held for 10 min). This enantioselective gas chromatographic separation was combined with a clean-up/enrichment procedure based on the modification of QuEChERS (quick, easy, cheap, effective, rugged and safe) method. Co-extractives were removed with graphitized carbon black/primary secondary amine (GCB/PSA) solid-phase extraction (SPE) cartridges using acetonitrile:toluene (3:1, v/v) as eluent. Gas chromatography/ion trap mass spectrometry (GC-ITMS) with electron ionization (EI) was then used for qualitative and quantitative determination of the simeconazole enantiomers. Two precursor-to-product ion transitions (m/z 121-101 and 195-153) with the best signal intensity were chosen to build the multiple-reaction monitoring (MRM) acquisition method. The limits of detection for each enantiomer of simeconazole in six food products ranged between 0.4 and 0.9 {mu}g kg{sup -1}, which were much lower than maximum residue levels (MRLs) established by Japan. The methodology was successfully applied for the enantioselective analysis of simeconazole enantiomers in real samples, indicating its efficacy in investigating the environmental

  1. Performance of the linear ion trap Orbitrap mass analyzer for qualitative and quantitative analysis of drugs of abuse and relevant metabolites in sewage water.

    Science.gov (United States)

    Bijlsma, Lubertus; Emke, Erik; Hernández, Félix; de Voogt, Pim

    2013-03-20

    This work illustrates the potential of liquid chromatography coupled to a hybrid linear ion trap Fourier Transform Orbitrap mass spectrometer for the simultaneous identification and quantification of 24 drugs of abuse and relevant metabolites in sewage water. The developed methodology consisted of automatic solid-phase extraction using Oasis HLB cartridges, chromatographic separation of the targeted drugs, full-scan accurate mass data acquisition under positive electrospray ionization mode over an m/z range of 50-600Da at a resolution of 30,000 FWHM and simultaneous MS(n) measurements to obtain information of fragment ions generated in the linear ion trap. Accurate mass of the protonated molecule, together with at least one nominal mass product ion and retention time allowed the confident identification of the compounds detected in these complex matrices. In addition to the highly reliable qualitative analysis, Orbitrap analyzer also proved to have satisfactory potential for quantification at sub-ppb analyte levels, a possibility that has been very little explored in the literature until now. The limits of quantification ranged from 4 to 68ngL(-1) in influent sewage water, and from 2 to 35ngL(-1) in effluent, with the exception of MDA, morphine and THC that presented higher values as a consequence of the high ionization suppression in this type of samples. Satisfactory recoveries (70-120%) and precision (abuse could be identified and quantified, mainly MDMA, benzoylecgonine, codeine, oxazepam and temazepam. Orbitrap also showed potential for retrospective investigation of ketamine metabolites in the samples without the need of additional analysis. Copyright © 2013 Elsevier B.V. All rights reserved.

  2. Atmospheric pressure helium afterglow discharge detector for gas chromatography

    Science.gov (United States)

    Rice, Gary; D'Silva, Arthur P.; Fassel, Velmer A.

    1986-05-06

    An apparatus for providing a simple, low-frequency electrodeless discharge system for atmospheric pressure afterglow generation. A single quartz tube through which a gas mixture is passed is extended beyond a concentric electrode positioned thereabout. A grounding rod is placed directly above the tube outlet to permit optical viewing of the discharge between the electrodes.

  3. Headspace solid-phase microextraction and gas chromatography ...

    African Journals Online (AJOL)

    Purpose: To extract and analyze the volatile components of Chrysanthemum morifolium Ramat. 'huaiju' by headspace solid-phase microextraction (HS-SPME) and gas chromatography–mass spectrometry. (GC–MS). Methods: Volatile components were extracted by HS-SPME and identified by GC–MS. The relative contents ...

  4. Headspace solid-phase microextraction and gas chromatography ...

    African Journals Online (AJOL)

    Purpose: To extract and analyze the volatile components of Chrysanthemum morifolium Ramat. 'huaiju' by headspace solid-phase microextraction (HS-SPME) and gas chromatography–mass spectrometry (GC–MS). Methods: Volatile components were extracted by HS-SPME and identified by GC–MS. The relative contents ...

  5. Atmospheric pressure helium afterglow discharge detector for gas chromatography

    Science.gov (United States)

    Rice, G.; D'Silva, A.P.; Fassel, V.A.

    1985-04-05

    An apparatus for providing a simple, low-frequency, electrodeless discharge system for atmospheric pressure afterglow generation. A single quartz tube through which a gas mixture is passed is extended beyond a concentric electrode positioned thereabout. A grounding rod is placed directly above the tube outlet to permit optical viewing of the discharge between the electrodes.

  6. An analytical study by gas liquid chromatography and radiochromatography of tritium labelled lebaycid

    International Nuclear Information System (INIS)

    Perez Garcia, M. M.

    1969-01-01

    The stability and purity of the syntheses products of Lebaycid: 0,0 dime thylfosfochlorothionate and 4 methyl-thio-m-cresol were investigated by gas liquid chromatography. The study on (CH 3 O) 2 PSC1 was made in a column of Silicone SE-30, Reoplex 400 using a thermal conductivity detector. The 99,4% pure product obtained from the preparative gas chromatograph was found to be stable within the duration of the experiment: seven months. (Author) 23 refs

  7. Changes in the basic experimental parameters of capillary gas chromatography in the 20th century.

    Science.gov (United States)

    Berezkin, V G; Viktorova, E N

    2003-01-24

    Studies of qualitative changes in capillary gas chromatography are of significant practical and scientific interest. This paper analyzes the evolution of the most important experimental chromatographic parameters over the last three decades and is based on the use of a new approach to scientometrical research that is referred to as applied scientometry. One essential feature of this approach is that it looks at the entire contents of each paper rather than only taking account its title, abstract. and references (as is typical for conventional scientometry). In this paper, we monitor how the most important chromatographic parameters, such as column length and diameter, layer thickness, stationary liquid phases, separation temperature mode. etc., have been evolving over the period 1970-2000. We used data from the following journals: Chromatographia, Journal of Chromatography, and Journal of High Resolution Chromatography and Chromatography Communications.

  8. Differential fragmentation patterns of pectin oligogalacturonides observed by nanoelectrospray quadrupole ion-trap mass spectrometry using automated spectra interpretation

    DEFF Research Database (Denmark)

    Mutenda, Kudzai E; Matthiesen, Rune; Roepstorff, Peter

    2007-01-01

    Oligogalacturonides of different degrees of polymerization (DP) and methyl esterification (DE) were structurally analyzed by nanoESI quadrupole ion-trap mass spectrometry. The fragmentation patterns of the oligogalacturonides were compared using the program 'Virtual Expert Mass Spectrometrist...... oligogalacturonides, cross-ring fragmentation gives more structural information than glycosidic bond cleavage. One implication of this is that more structural information is obtained when analyzing methyl-esterified oligogalacturonides than non-methyl-esterified ones in an ion-trap instrument. This is of particular...

  9. Strong coupling between a single nitrogen-vacancy spin and the rotational mode of diamonds levitating in an ion trap

    Science.gov (United States)

    Delord, T.; Nicolas, L.; Chassagneux, Y.; Hétet, G.

    2017-12-01

    A scheme for strong coupling between a single atomic spin and the rotational mode of levitating nanoparticles is proposed. The idea is based on spin readout of nitrogen-vacancy centers embedded in aspherical nanodiamonds levitating in an ion trap. We show that the asymmetry of the diamond induces a rotational confinement in the ion trap. Using a weak homogeneous magnetic field and a strong microwave driving we then demonstrate that the spin of the nitrogen-vacancy center can be strongly coupled to the rotational mode of the diamond.

  10. Mats and LaSpec: High-precision experiments using ion traps and lasers at Fair

    Energy Technology Data Exchange (ETDEWEB)

    Rodriguez, D.; Lallena, A.M.; Blaum, K.; Bohm, C.; Cakirli, R.B.; Crespo Lopez-Urrutia, J.R.; Eliseev, S.; Ketelaer, J.; Kreim, M.S.; Kowalska, M.; Litvinov, Y.A.; Nagy, S.; Neidherr, D.; Repp, J.; Roux, C.; Schabinger, B.; Ullrich, J.; Nortershauser, W.; Eberhardt, K.; Geppert, C.; Kramer, J.; Krieger, A.; Sanchez, R.; Ahammed, M.; Das, P.; Ray, A.; Algora, A.; Rubio, B.; Tain, J.L.; Audi, G.; Lunney, D.; Naimi, S.; Aysto, J.; Jokinen, A.; Kolhinen, V.; Moore, I.; Beck, D.; Block, M.; Geissel, H.; Heinz, S.; Herfurth, F.; Litvinov, Y.A.; Minaya-Ramirez, E.; Plab, W.R.; Quint, W.; Scheidenberger, C.; Winkler, M.; Bender, M.; Billowes, J.; Campbell, P.; Flanagan, K.T.; Schwarz, S.; Bollen, G.; Ferrer, R.; George, S.; Kester, O.; Brodeur, M.; Brunner, T.; Delheij, P.; Dilling, J.; Ettenauer, S.; Lapierre, A.; Bushaw, B.A.; Cano-Ott, D.; Martinez, T.; Cortes, G.; Gomez-Hornillos, M.B.; Dax, A.; Herlert, A.; Yordanov, D.; De, A.; Dickel, T.; Geissel, H.; Jesch, C.; Kuhl, T.; Petrick, M.; PlaB, W.R.; Scheidenberger, C.; Garcia-Ramos, J.E.; Gartzke, E.; Habs, D.; Szerypo, J.; Thirolf, P.G.; Weber, C.; Gusev, Y.; Nesterenko, D.; Novikov, Y.N.; Popov, A.; Seliverstov, M.; Vasiliev, A.; Vorobjev, G.; Heenen, P.H.; Marx, G.; Schweikhard, L.; Ziegler, F.; Hobein, M.; Schuch, R.; Solders, A.; Suhonen, M.; Huber, G.; Wendt, K.; Huyse, M.; Koudriavtsev, I.; Neyens, G.; Van Duppen, P.; Le Blanc, F.; Matos, M.; Reinhard, P.G.; Schneider, D.

    2010-05-15

    Nuclear ground state properties including mass, charge radii, spins and moments can be determined by applying atomic physics techniques such as Penning-trap based mass spectrometry and laser spectroscopy. The MATS and LaSpec setups at the low-energy beamline at FAIR will allow us to extend the knowledge of these properties further into the region far from stability. With MATS (Precision Measurements of very short-lived nuclei using an Advanced Trapping System for highly-charged ions) at FAIR we aim to apply several techniques to very short-lived radionuclides: High-accuracy mass measurements, in-trap conversion electron and alpha spectroscopy, and trap-assisted spectroscopy. The experimental setup of MATS is a unique combination of an electron beam ion trap for charge breeding, ion traps for beam preparation, and a high-precision Penning trap system for mass measurements and decay studies. For the mass measurements, MATS offers both a high accuracy and a high sensitivity. A relative mass uncertainty of 10{sup -9} can be reached by employing highly-charged ions and a non-destructive Fourier-Transform Ion-Cyclotron-Resonance (FT-ICR) detection technique on single stored ions. Decay studies in ion traps will become possible with MATS. Laser spectroscopy of radioactive isotopes and isomers is an efficient and model-independent approach for the determination of nuclear ground and isomeric state properties. Hyperfine structures and isotope shifts in electronic transitions exhibit readily accessible information on the nuclear spin, magnetic dipole and electric quadrupole moments as well as root-mean-square charge radii. The accuracy of laser-spectroscopic-determined nuclear properties is very high while requirements concerning production rates are moderate. This Technical Design Report describes a new Penning trap mass spectrometry setup as well as a number of complementary experimental devices for laser spectroscopy. Since MATS and LaSpec require high-quality low

  11. Capillary gas chromatography for the determination of halogenated micro-contaminants

    NARCIS (Netherlands)

    Boer, de J.

    1999-01-01

    Capillary gas chromatography (GC) is a very useful technique for the determination of complex mixtures of halogenated contaminants. Initially, this technique has shown its merits for the determination of polychlorinated biphenyls and organochlorine pesticides. In addition, it has also broken new

  12. Determination of daminozide residues in apples using gas chromatography with nitrogen-phosphorus detection

    NARCIS (Netherlands)

    Brinkman, J.H.W.; Dijk, A.G. van; Wagenaar, R.; Quirijns, J.K.

    1996-01-01

    A method was developed for the determination of daminozide in apples using gas chromatography (GC) with nitrogen-phosphorus detection (NPD). Daminozide is hydrolysed to 1,1-dimethylhydrazine (UDMH) by alkaline digestion. The UDMH generated is distilled from the apple matrix, derivatized with

  13. The properties of the wood-polystyrene interphase determined by inverse gas chromatography

    Science.gov (United States)

    John Simonsen; Zhenqiu Hong; Timothy G. Rials

    1997-01-01

    The properties of the interphase in wood-polymer composites are important determinants of the properties of the final composite. This study used inverse gas chromatography (IGC) to measure interphasal properties of composites of polystyrene and two types of wood fiber fillers and an inoranic substrate (CW) with varying amounts of surface coverage of polystyrene. Glass...

  14. Surface Energy Characteristics of Toner Particles by Automated Inverse Gas Chromatography

    NARCIS (Netherlands)

    Segeren, L.H.G.J.; Wouters, M.E.L.; Bos, M.; van den Berg, J.W.A.; Vancso, Gyula J.

    2002-01-01

    Inverse gas chromatography (IGC) was applied to the surface energy study of surfaces of toner particles. The dispersive component of the surface energy was determined for three toner materials by infinite dilution IGC. The values obtained were comparable to the values obtained from contact angle

  15. Phase Equilibrium and Diffusion of Solvents in Polybutadiene: A Capillary-Column Inverse Gas Chromatography Study

    NARCIS (Netherlands)

    Cai, W.D.; Ramesh, N.; Tihminlioglu, F.; Danner, R.P.; Duda, J.L.; de Haan, A.B.

    2002-01-01

    The capillary-column inverse gas chromatography method was used to measure the diffusion and partition coefficients of ethylbenzene, styrene, and acrylonitrile in polybutadiene (PBD) at infinite dilution of the solvents. Experiments were performed over a temperature range of 50-125 °C. At

  16. Chiral gas chromatography for the determination of 1,2-O-isopropylidene-sn-glycerol stereoisomers

    NARCIS (Netherlands)

    Dröge, M.J; Bos, R.; Woerdenbag, H.J.; Quax, Wim; Droge, MJ

    2003-01-01

    A stereospecific gas chromatography (GC) method using a (6-O-tButyldimethylsilyl-2,3-di-O-methyl)-beta-cyclodextrin as the chiral stationary phase has been developed and validated for the determination of the enantiomers of 1,2-O-isopropylidene-sn-glycerol (IPG), an important chiral synthon, in

  17. Incorporation of Gas Chromatography-Mass Spectrometry into the Undergraduate Organic Chemistry Laboratory Curriculum

    Science.gov (United States)

    Giarikos, Dimitrios G.; Patel, Sagir; Lister, Andrew; Razeghifard, Reza

    2013-01-01

    Gas chromatography-mass spectrometry (GC-MS) is a powerful analytical tool for detection, identification, and quantification of many volatile organic compounds. However, many colleges and universities have not fully incorporated this technique into undergraduate teaching laboratories despite its wide application and ease of use in organic…

  18. Determination of petroleum fractions as contaminants in the waters by gas chromatography

    International Nuclear Information System (INIS)

    Kubinec, R.; Mracnova, R.; Kuran, P.; Ostrovsky, I.; Sojak, L.

    1995-01-01

    The method of micro-extraction of petroleum fractions from water and analysis using gas chromatography was developed. This method can be used for the analysis of gaseous oil and mineral oil in the water wit the detection limit 12 ppb and 18 ppb, respectively

  19. Quantitation of monomers in poly(glyerol-co-diacid) gels using gas chromatography

    Science.gov (United States)

    The validation of a gas chromatography (GC) method developed to quantify amounts of starting material from the synthesis of hyperbranched polymers made from glycerol and either succinic acid, glutaric acid, or azelaic acid is described. The GC response to concentration was linear for all starting r...

  20. Gas Chromatography/mass Spectrometry Analysis of Exhaled Leukotrienes in Asthmatic Patients

    Czech Academy of Sciences Publication Activity Database

    Čáp, P.; Chládek, J.; Pehal, F.; Malý, Marek; Petrů, V.; Barnes, P.J.; Montuschi, P.

    2004-01-01

    Roč. 59, č. 6 (2004), s. 465-470 ISSN 0040-6376 Source of funding: V - iné verejné zdroje Keywords : asthma * breath condensate * gas chromatography/mass spectrometry * leukotrienes Subject RIV: BB - Applied Statistics, Operational Research Impact factor: 5.040, year: 2004

  1. Anti-Sickling Potential of Aloe Vea Extract Iii: Gas Chromatography ...

    African Journals Online (AJOL)

    The neutral metabolite obtained from ethanol extract of Aloe vera was characterized using the Gas Chromatography/Mass Spectroscopy. The results showed that the oil contained five different compounds, which included hexadecanoic acid, ethyl ester; phytol; 2-methyloctadeca-3,13-diene-1-ol; cotadeca-9,12,15-trienoic ...

  2. Studying Intermolecular Forces with a Dual Gas Chromatography and Boiling Point Investigation

    Science.gov (United States)

    Cunningham, William Patrick; Xia, Ian; Wickline, Kaitlyn; Huitron, Eric Ivan Garcia; Heo, Jun

    2018-01-01

    A procedure for the study of structural differences and intermolecular attraction between ethanol and 1-butanol based in laboratory work is described. This study provides comparisons of data retrieved from both a determination of boiling point and gas chromatography traces for the mixture. The methodology reported here should provide instructors…

  3. 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...

  4. Ion counting method and it's operational characteristics in gas chromatography-mass spectrometry

    International Nuclear Information System (INIS)

    Fujii, Toshihiro

    1976-01-01

    Ion counting method with continuous channel electron multiplier which affords the direct detection of very small ion currents and it's operational characteristics were studied in gas chromatography-mass spectrometry. Then this method was applied to the single ion detection technique of GC-MS. A detection limit was measured, using various standard samples of low level concentration. (auth.)

  5. Identification of Synthetic Polymers and Copolymers by Analytical Pyrolysis-Gas Chromatography/Mass Spectrometry

    Science.gov (United States)

    Kusch, Peter

    2014-01-01

    An experiment for the identification of synthetic polymers and copolymers by analytical pyrolysis-gas chromatography/mass spectrometry (Py-GC/MS) was developed and performed in the polymer analysis courses for third-year undergraduate students of chemistry with material sciences, and for first-year postgraduate students of polymer sciences. In…

  6. Review of recent developments and applications in low-pressure (vacuum outlet) gas chromatography

    Science.gov (United States)

    The concept of low pressure (LP) vacuum outlet gas chromatography (GC) was introduced more than 50 years ago, but it was not until the 2000s that its theoretical applicability to fast analysis of GC-amenable chemicals was realized. In practice, LPGC is implemented by placing the outlet of a short, ...

  7. Gas chromatography-mass spectrometry and high-performance liquid chromatographic analyses of thermal degradation products of common plastics.

    Science.gov (United States)

    Pacáková, V; Leclercq, P A

    1991-08-30

    The thermo-oxidation of five commonly used materials, namely low-density polyethylene, retarded polyethylene, paper with a polyethylene foil, a milk package and filled polypropylene, was studied. Capillary gas chromatography and gas chromatography-mass spectrometry were used to analyze the volatile degradation products, while high-performance liquid chromatography was employed to measure polycyclic aromatic hydrocarbons. The results are discussed from the point of view of toxicity of the products.

  8. Design and Testing of a Linear Ion Trap for the Mars Organic Molecule Analyzer (MOMA) Investigation on the 2018 ExoMars Rover

    Science.gov (United States)

    Brinckerhoff, W. B.; van Amerom, F.; Danell, R.; Pinnick, V. T.; Arevalo, R. D.; Li, X.; Hovmand, L.; Siljestrom, S.; Mahaffy, P. R.; Goetz, W.; Goesmann, F.; Steininger, H.

    2013-12-01

    The 2018 ExoMars rover mission includes the Mars Organic Molecule Analyzer (MOMA) investigation. MOMA will examine the chemical composition of samples acquired from depths of up to two meters below the martian surface, where organics may be protected from radiative and oxidative degradation. When combined with the complement of instruments in the rover's Pasteur Payload, MOMA has the potential to reveal the presence of a wide range of organics preserved in a variety of mineralogical environments, and to begin to understand the structural character and potential origin of those compounds. MOMA includes an ion trap mass spectrometer (ITMS) that is designed to analyze molecular composition of (i) gas evolved from pyrolyzed powder samples and separated on a gas chromatograph and (ii) ions directly desorbed from solid samples at Mars ambient pressure using a pulsed laser and a fast-valve capillary ion inlet system. This 'dual source' approach gives MOMA unprecedented breadth of detection over a wide range of molecular weights and volatilities. Analysis of nonvolatile, higher-molecular weight organics such as carboxylic acids and peptides even in the presence of significant perchlorate concentrations is enabled by the extremely short (~1 ns) pulses of the desorption laser. Use of the ion trap's tandem mass spectrometry mode permits selective focus on key species for isolation and controlled fragmentation, providing structural analysis capabilities. The flight-like engineering test unit (ETU) of the ITMS, now under construction, will be used to verify breadboard performance with high fidelity, while simultaneously supporting the development of analytical scripts and spectral libraries using synthetic and natural Mars analog samples guided by current results from MSL. ETU campaign data will strongly advise the specifics of the calibration applied to the MOMA flight model as well as the science operational procedures during the mission.

  9. Design and Application of a High-Temperature Linear Ion Trap Reactor

    Science.gov (United States)

    Jiang, Li-Xue; Liu, Qing-Yu; Li, Xiao-Na; He, Sheng-Gui

    2018-01-01

    A high-temperature linear ion trap reactor with hexapole design was homemade to study ion-molecule reactions at variable temperatures. The highest temperature for the trapped ions is up to 773 K, which is much higher than those in available reports. The reaction between V2O6 - cluster anions and CO at different temperatures was investigated to evaluate the performance of this reactor. The apparent activation energy was determined to be 0.10 ± 0.02 eV, which is consistent with the barrier of 0.12 eV calculated by density functional theory. This indicates that the current experimental apparatus is prospective to study ion-molecule reactions at variable temperatures, and more kinetic details can be obtained to have a better understanding of chemical reactions that have overall barriers. [Figure not available: see fulltext.

  10. Low jitter metal vapor vacuum arc ion source for electron beam ion trap injections

    International Nuclear Information System (INIS)

    Holland, Glenn E.; Boyer, Craig N.; Seely, John F.; Tan, J.N.; Pomeroy, J.M.; Gillaspy, J.D.

    2005-01-01

    We describe a metal vapor vacuum arc (MeVVA) ion source containing eight different cathodes that are individually selectable via the control electronics which does not require moving components in vacuum. Inside the vacuum assembly, the arc plasma is produced by means of a 30 μs pulse (26 kV,125 A) delivering 2.4 mC of charge to the cathode sample material. The trigger jitter is minimized ( 9 ions/cm 2 , measured by an unbiased Faraday cup positioned 20 cm from the extractor grid, at discharge rates up to 5 Hz. The electronic triggering of the discharge is via a fiber optic interface. We present the design, fabrication details, and performance of this MeVVA, recently installed on the National Institute of Standards and Technology electron beam ion trap (EBIT)

  11. Studies of space charge effects on operating electron beam ion trap at low electron beam energy

    Energy Technology Data Exchange (ETDEWEB)

    Jin, Xuelong; Fei, Zejie; Xiao, Jun; Lu, Di; Hutton, Roger [The Key Lab of Applied Ion Beam Physics, Ministry of Education (China); Shanghai EBIT Laboratory, Modern Physics Institute, Fudan University, Shanghai (China); Zou, Yaming, E-mail: zouym@fudan.edu.cn [The Key Lab of Applied Ion Beam Physics, Ministry of Education (China); Shanghai EBIT Laboratory, Modern Physics Institute, Fudan University, Shanghai (China)

    2013-08-21

    An electron beam ion trap (EBIT) is a powerful machine for disentangling studies of atomic processes in plasmas. To assist studies on edge plasma spectroscopic diagnostics, a very low energy EBIT, SH-PermEBIT, has been set up at the Shanghai EBIT lab. Large amounts of simulation works were done to study the factors which hinder the EBIT from operation at very low electron beam energies. Under the guide line of the simulation results, we finally managed to successfully reach 60 eV for the lower end of the electron beam energy with a beam transmission above 57%. In this presentation, simulation studies of the space charge effect, which is one of the most important causes of beam loss, was made based on Tricomp (Field precision)

  12. Simulating quantum effects of cosmological expansion using a static ion trap

    Science.gov (United States)

    Menicucci, Nicolas C.; Olson, S. Jay; Milburn, Gerard J.

    2010-09-01

    We propose a new experimental test bed that uses ions in the collective ground state of a static trap to study the analogue of quantum-field effects in cosmological spacetimes, including the Gibbons-Hawking effect for a single detector in de Sitter spacetime, as well as the possibility of modeling inflationary structure formation and the entanglement signature of de Sitter spacetime. To date, proposals for using trapped ions in analogue gravity experiments have simulated the effect of gravity on the field modes by directly manipulating the ions' motion. In contrast, by associating laboratory time with conformal time in the simulated universe, we can encode the full effect of curvature in the modulation of the laser used to couple the ions' vibrational motion and electronic states. This model simplifies the experimental requirements for modeling the analogue of an expanding universe using trapped ions, and it enlarges the validity of the ion-trap analogy to a wide range of interesting cases.

  13. Electrospray ionization ion-trap multiple-stage mass spectrometry of Quillaja saponins.

    Science.gov (United States)

    Bankefors, Johan; Broberg, Susanna; Nord, Lars I; Kenne, Lennart

    2011-07-01

    Fifteen identified C-18 fatty acyl-containing saponin structures from Quillaja saponaria Molina have been investigated by electrospray ionization ion-trap multiple-stage mass spectrometry (ESI-IT-MS(n)) in positive ion mode. Their MS(1)-MS(3) spectra were analyzed and ions corresponding to useful fragments, important for the structural identification of Quillaja saponins, were recognized. A few key fragments could describe the structural variations in the C-3 and the C-28 oligosaccharides of the Quillaja saponins. A flowchart involving a stepwise procedure based on key fragments from the MS(1)-MS(3) spectra of these saponins, together with key fragments from these saponins and 13 previously investigated saponins, was constructed for the identification of structural elements in Quillaja saponins. Peak intensity ratios in MS(3) spectra were found to be correlated to structural features of the investigated saponins and is therefore of value for the identification of regioisomers. Copyright © 2011 John Wiley & Sons, Ltd.

  14. Design and operation of a warm electron beam ion trap (WEBIT)

    International Nuclear Information System (INIS)

    McDonald, J.W.; Schneider, D.

    1993-01-01

    This contribution describes the operating principles and capabilities of a Non-Cryogenic or Warm Electron Beam Ion Trap (WEBIT). WEBIT is designed as a table top device capable of producing intermediately charged ions up to about Xe40 + at a rate of about 10 5 ions per second. WEBIT consists of an energetic electron beam that is compressed in a strong magnetic field, a potential trap and an ion extraction system. The electron beam ionizes the low-charge state ions via repeated collisions while its space charge confines the ions radially. The potential trap is such that the ions are trapped longitudinally within a potential well formed by the drift tubes. The ion extraction system consists of a focusing Einsel lens and a magnetic analyzer to momentum analyze the ions. Preliminary results for the production of highly charged ions are discussed

  15. Charting molecular composition of phosphatidylcholines by fatty acid scanning and ion trap MS3 fragmentation

    DEFF Research Database (Denmark)

    Ekroos, Kim; Ejsing, Christer S.; Bahr, Ute

    2003-01-01

    preliminary separation of lipid classes or of individual molecular species, enzymatic digestion, or chemical derivatization. The approach was validated by the comparative analysis of the molecular composition of PCs from human red blood cells. In the total lipid extract of Madin-Darby canine kidney II cells......The molecular composition of phosphatidylcholines (PCs) in total lipid extracts was characterized by a combination of multiple precursor ion scanning on a hybrid quadrupole time-of-flight mass spectrometer and MS3 fragmentation on an ion trap mass spectrometer. Precursor ion spectra for 50 acyl...... spectrometer quantified the relative amount of their positional isomers, thus providing the most detailed and comprehensive characterization of the molecular composition of the pool of PCs at the low-picomole level. The method is vastly simplified, compared with conventional approaches, and does not require...

  16. On the combination of a low energy hydrogen atom beam with a cold multipole ion trap

    Energy Technology Data Exchange (ETDEWEB)

    Borodi, Gheorghe

    2008-12-09

    The first part of the activities of this thesis was to develop a sophisticated ion storage apparatus dedicated to study chemical processes with atomic hydrogen. The integration of a differentially pumped radical beam source into an existing temperature variable 22- pole trapping machine has required major modifications. Since astrophysical questions have been in the center of our interest, the introduction first gives a short overview of astrophysics and -chemistry. The basics of ion trapping in temperature variable rf traps is well-documented in the literature; therefore, the description of the basic instrument (Chapter 2) is kept rather short. Much effort has been put into the development of an intense and stable source for hydrogen atoms the kinetic energy of which can be changed. Chapter 3 describes this module in detail with emphasis on the integration of magnetic hexapoles for guiding the atoms and special treatments of the surfaces for reducing H-H recombination. Due to the unique sensitivity of the rf ion trapping technique, this instrument allows one to study a variety of reactions of astrochemical and fundamental interest. The results of this work are summarized in Chapter 4. Reactions of CO{sub 2}{sup +} with hydrogen atoms and molecules have been established as calibration standard for in situ determination of H and H{sub 2} densities over the full temperature range of the apparatus (10 K-300 K). For the first time, reactions of H- and D-atoms with the ionic hydrocarbons CH{sup +}, CH{sub 2}{sup +}, and CH{sub 4}{sup +} have been studied at temperatures of interstellar space. A very interesting, not yet fully understood collision system is the interaction of protonated methane with H. The outlook presents some ideas, how to improve the new instrument and a few reaction systems are mentioned which may be studied next. (orig.)

  17. Microsecond pulsed hydrogen/deuterium exchange of electrosprayed ubiquitin ions stored in a linear ion trap.

    Science.gov (United States)

    Rajabi, Khadijeh

    2015-02-07

    A pulse of D2O vapour on the order of microseconds is allowed to react with the +6 to +9 charge states of ubiquitin confined in a linear ion trap (LIT). Two envelopes of peaks are detected for the ions of ubiquitin, corresponding to the ions that exchange more quickly and more slowly. The deuterium uptake of the protonated sites on ubiquitin ions accounts for the ion population with the fast exchange. The hydrogen/deuterium exchange (HDX) kinetics of ubiquitin ions trapped in the LIT for 200 ms showed comparable structural transitions to those trapped for 300 ms. When ions are trapped for longer, i.e. up to 2000 ms, mainly the slow exchanging ion population is detected. In all experiments the +7 ions exchange the most, suggesting a short distance between the surface protonated sites and nearby charged sites, and concomitantly high accessibility of surface protonated sites towards D2O. The +6 ions are more compact than the +7 ions but have one fewer protonated site, therefore fewer surface availabilities for D2O attack. The data suggest that the +6 ions keep most of their solution-phase contacts intact while the hydrophobic core is slightly interrupted in the +7 ions, possibly due to the exposure of charged His68 that is normally buried in the hydrophobic pocket. The +8 and +9 ions have more protonated sites but are less compact than the +7 ions because of Coulombic repulsion, resulting in a larger distance between the protonated sites and the basic sites. The data indicate that the HDX mechanism of ions with the slower exchange corresponding to the second envelope of peaks is primarily governed via a relay mechanism. The results suggest that the pulsed HDX MS method is sampling a population of ubiquitin ions with a similar backbone fold to the solution.

  18. On the combination of a low energy hydrogen atom beam with a cold multipole ion trap

    International Nuclear Information System (INIS)

    Borodi, Gheorghe

    2008-01-01

    The first part of the activities of this thesis was to develop a sophisticated ion storage apparatus dedicated to study chemical processes with atomic hydrogen. The integration of a differentially pumped radical beam source into an existing temperature variable 22- pole trapping machine has required major modifications. Since astrophysical questions have been in the center of our interest, the introduction first gives a short overview of astrophysics and -chemistry. The basics of ion trapping in temperature variable rf traps is well-documented in the literature; therefore, the description of the basic instrument (Chapter 2) is kept rather short. Much effort has been put into the development of an intense and stable source for hydrogen atoms the kinetic energy of which can be changed. Chapter 3 describes this module in detail with emphasis on the integration of magnetic hexapoles for guiding the atoms and special treatments of the surfaces for reducing H-H recombination. Due to the unique sensitivity of the rf ion trapping technique, this instrument allows one to study a variety of reactions of astrochemical and fundamental interest. The results of this work are summarized in Chapter 4. Reactions of CO 2 + with hydrogen atoms and molecules have been established as calibration standard for in situ determination of H and H 2 densities over the full temperature range of the apparatus (10 K-300 K). For the first time, reactions of H- and D-atoms with the ionic hydrocarbons CH + , CH 2 + , and CH 4 + have been studied at temperatures of interstellar space. A very interesting, not yet fully understood collision system is the interaction of protonated methane with H. The outlook presents some ideas, how to improve the new instrument and a few reaction systems are mentioned which may be studied next. (orig.)

  19. Analytical accuracy of hydrogen measurement using gas chromatography with thermal conductivity detection.

    Science.gov (United States)

    Weijun, Yao

    2015-08-01

    Gas chromatography employing a thermal conductivity detector with a nitrogen carrier gas and a molecular sieve 5 Å column is commonly used for the analysis of widely varying hydrogen concentrations. Flow variation of the column, caused by carrier gas adsorption, affects the peak shape and impacts the analytical accuracy. The mechanism and factors affecting the adsorption effect are explored, errors caused by the deviation from the linearity of the detector's response are considered, and practical advice is given for improving the analytical accuracy. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  20. Development of conjugate methods with gas chromatography for inorganic compounds analysis

    International Nuclear Information System (INIS)

    Baccan, N.

    1975-01-01

    The application of gas chromatography combined with mass spectrometry or with nuclear methods for the analysis of inorganic compounds is studied. The advantages of the use of a gas chromatograph coupled with a quadrupole mass spectrometer or with a high resolution radiation detector, are discussed. We also studied the formation and solvent extraction of metal chelates; an aliquot of the organic phase was directly injected into the gas chromatograph and the eluted compounds were detected by mass spectrometry or, when radioactive, by nuclear methods. (author)

  1. Determination of maximal amount of minor gases adsorbed in a shale sample by headspace gas chromatography.

    Science.gov (United States)

    Zhang, Chun-Yun; Hu, Hui-Chao; Chai, Xin-Sheng; Pan, Lei; Xiao, Xian-Ming

    2014-02-07

    In this paper, we present a novel method for determining the maximal amount of ethane, a minor gas species, adsorbed in a shale sample. The method is based on the time-dependent release of ethane from shale samples measured by headspace gas chromatography (HS-GC). The study includes a mathematical model for fitting the experimental data, calculating the maximal amount gas adsorbed, and predicting results at other temperatures. The method is a more efficient alternative to the isothermal adsorption method that is in widespread use today. Copyright © 2013 Elsevier B.V. All rights reserved.

  2. Metal-Organic Framework Thin Films as Stationary Phases in Microfabricated Gas-Chromatography Columns.

    Energy Technology Data Exchange (ETDEWEB)

    Read, Douglas [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Sillerud, Colin Halliday [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)

    2016-01-01

    The overarching goal of this project is to integrate Sandia's microfabricated gas-chromatography ( GC) columns with a stationary phase material that is capable of retaining high-volatility chemicals and permanent gases. The successful integration of such a material with GCs would dramatically expand the repertoire of detectable compounds for Sandia's various microanalysis systems. One such promising class of candidate materials is metal-organic frameworks (MOFs). In this report we detail our methods for controlled deposition of HKUST-1 MOF stationary phases within GC columns. We demonstrate: the chromatographic separation of natural gas; a method for determining MOF film thickness from chromatography alone; and the first-reported GC x GC separation of natural gas -- in general -- let alone for two disparate MOF stationary phases. In addition we determine the fundamental thermodynamic constant for mass sorption, the partition coefficient, for HKUST-1 and several light hydrocarbons and select toxic industrial chemicals.

  3. Extreme ultra-violet emission spectroscopy of highly charged gadolinium ions with an electron beam ion trap

    International Nuclear Information System (INIS)

    Ohashi, Hayato; Nakamura, Nobuyuki; Sakaue, Hiroyuki A

    2013-01-01

    We present extreme ultra-violet emission spectra of highly charged gadolinium ions obtained with an electron beam ion trap at electron energies of 0.53–1.51 keV. The electron energy dependence of the spectra in the 5.7–11.3 nm range is compared with calculation with the flexible atomic code. (paper)

  4. Applications of the fractional calculus to study the physical theory of ion motion in a quadrupole ion trap.

    Science.gov (United States)

    Chaharborj, Sarkhosh S; Moameni, Abbas

    2017-10-01

    In this article, fractional calculus has been applied to study the motion of ions in a three-dimensional radio frequency quadrupole ion trap; we have called this arrangement a fractional quadrupole ion trap. The main purpose of the article is to show that by controlling the fractional parameter of a trapped ion, one can gain a more efficient mass separation. In what follows, we will see that with decreasing the fractional parameter, we can achieve a smaller first stability region. Note that a small stability diagram will result in a good and acceptable mass separation. Various methods can be proposed to obtain a desired ion acceleration with a sufficient accuracy for good mass separation, which is similar to the one obtained by a fractional ion trap. Some of these methods are using the effects of a damping force, a magnetic field or both on the confinement of particles in the quadrupole ion trap. The first stability regions are plotted for all of the aforementioned methods, and simulation results are provided to compare them with those for the fractional case.

  5. Negative electrospray, ion trap multistage mass spectrometry of synthetic fragments of the O-PS of Vibrio cholerae O : 1

    Czech Academy of Sciences Publication Activity Database

    Bekešová, S.; Kováčik, V.; Chmelík, Josef; Kováč, P.

    2006-01-01

    Roč. 12, č. 1 (2006), s. 43-49 ISSN 1469-0667 Institutional research plan: CEZ:AV0Z40310501 Keywords : electrospray ionization * negative multistage ion trap mass spectra * synthetic fragments of the lipopolysaccharide of Vibrio cholerae Subject RIV: CB - Analytical Chemistry, Separation Impact factor: 1.438, year: 2006

  6. A laser desorption-electron impact ionization ion trap mass spectrometer for real-time analysis of single atmospheric particles

    Science.gov (United States)

    Simpson, E. A.; Campuzano-Jost, P.; Hanna, S. J.; Robb, D. B.; Hepburn, J. H.; Blades, M. W.; Bertram, A. K.

    2009-04-01

    A novel aerosol ion trap mass spectrometer combining pulsed IR laser desorption with electron impact (EI) ionization for single particle studies is described. The strengths of this instrument include a two-step desorption and ionization process to minimize matrix effects; electron impact ionization, a universal and well-characterized ionization technique; vaporization and ionization inside the ion trap to improve sensitivity; and an ion trap mass spectrometer for MSn experiments. The instrument has been used for mass spectral identification of laboratory generated pure aerosols in the 600 nm-1.1 [mu]m geometric diameter range of a variety of aromatic and aliphatic compounds, as well as for tandem mass spectrometry studies (up to MS3) of single caffeine particles. We investigate the effect of various operational parameters on the mass spectrum and fragmentation patterns. The single particle detection limit of the instrument was found to be a 325 nm geometric diameter particle (8.7 × 107 molecules or 22 fg) for 2,4-dihydroxybenzoic acid. Lower single particle detection limits are predicted to be attainable by modifying the EI pulse. The use of laser desorption-electron impact (LD-EI) in an ion trap is a promising technique for determining the size and chemical composition of single aerosol particles in real time.

  7. Quantitation of isobaric phosphatidylcholine species in human plasma using a hybrid quadrupole linear ion-trap mass spectrometer

    Czech Academy of Sciences Publication Activity Database

    Žáček, Petr; Bukowski, M.; Rosenberger, T. A.; Picklo, M.

    2016-01-01

    Roč. 57, č. 12 (2016), s. 2225-2234 ISSN 0022-2275 Institutional support: RVO:61388963 Keywords : shotgun lipidomics * triple quadrupole/ion-trap * human blood plasma * phosphatidylcholines Subject RIV: CB - Analytical Chemistry, Separation Impact factor: 4.810, year: 2016 http://www.jlr.org/content/57/12/2225.full

  8. Chemometrics comparison of gas chromatography with mass spectrometry and comprehensive two-dimensional gas chromatography with time-of-flight mass spectrometry Daphnia magna metabolic profiles exposed to salinity.

    Science.gov (United States)

    Parastar, Hadi; Garreta-Lara, Elba; Campos, Bruno; Barata, Carlos; Lacorte, Silvia; Tauler, Roma

    2018-02-27

    The performances of gas chromatography with mass spectrometry and of comprehensive two-dimensional gas chromatography with time-of-flight mass spectrometry are examined through the comparison of Daphnia magna metabolic profiles. Gas chromatography with mass spectrometry and comprehensive two-dimensional gas chromatography with mass spectrometry were used to compare the concentration changes of metabolites under saline conditions. In this regard, a chemometric strategy based on wavelet compression and multivariate curve resolution-alternating least squares is used to compare the performances of gas chromatography with mass spectrometry and comprehensive two-dimensional gas chromatography with time-of-flight mass spectrometry for the untargeted metabolic profiling of Daphnia magna in control and salinity-exposed samples. Examination of the results confirmed the outperformance of comprehensive two-dimensional gas chromatography with time-of-flight mass spectrometry over gas chromatography with mass spectrometry for the detection of metabolites in D. magna samples. The peak areas of multivariate curve resolution-alternating least squares resolved elution profiles in every sample analyzed by comprehensive two-dimensional gas chromatography with time-of-flight mass spectrometry were arranged in a new data matrix that was then modeled by partial least squares discriminant analysis. The control and salt-exposed daphnids samples were discriminated and the most relevant metabolites were estimated using variable importance in projection and selectivity ratio values. Salinity de-regulated 18 metabolites from metabolic pathways involved in protein translation, transmembrane cell transport, carbon metabolism, secondary metabolism, glycolysis, and osmoregulation. © 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  9. Phytochemical Profile of Erythrina variegata by Using High-Performance Liquid Chromatography and Gas Chromatography-Mass Spectroscopy Analyses.

    Science.gov (United States)

    Muthukrishnan, Suriyavathana; Palanisamy, Subha; Subramanian, Senthilkumar; Selvaraj, Sumathi; Mari, Kavitha Rani; Kuppulingam, Ramalingam

    2016-08-01

    Natural products derived from plant sources have been utilized to treat patients with numerous diseases. The phytochemical constituents present in ethanolic leaf extract of Erythrina variegata (ELEV) were identified by using high-performance liquid chromatography (HPLC) and gas chromatography-mass spectroscopy (GC-MS) analyses. Shade dried leaves were powdered and extracted with ethanol for analyses through HPLC to identify selected flavonoids and through GC-MS to identify other molecules. The HPLC analysis of ELEV showed the presence of gallic and caffeic acids as the major components at concentrations of 2.0 ppm and 0.1 ppm, respectively, as well as other components. GC-MS analysis revealed the presence of 3-eicosyne; 3,7,11,15-tetramethyl-2-hexadecen-1-ol; butanoic acid, 3-methyl-3,7-dimethyl-6-octenyl ester; phytol; 1,2-benzenedicarboxylic acid, diundecyl ester; 1-octanol, 2-butyl-; squalene; and 2H-pyran, 2-(7-heptadecynyloxy) tetrahydro-derivative. Because pharmacopuncture is a new evolving natural mode that uses herbal extracts for treating patients with various ailments with minimum pain and maximum effect, the results of this study are particularly important and show that ELEV possesses a wide range of phytochemical constituents, as indicated above, as effective active principle molecules that can be used individually or in combination to treat patients with various diseases. Copyright © 2016. Published by Elsevier B.V.

  10. Phytochemical Profile of Erythrina variegata by Using High-Performance Liquid Chromatography and Gas Chromatography-Mass Spectroscopy Analyses

    Directory of Open Access Journals (Sweden)

    Suriyavathana Muthukrishnan

    2016-08-01

    Full Text Available Natural products derived from plant sources have been utilized to treat patients with numerous diseases. The phytochemical constituents present in ethanolic leaf extract of Erythrina variegata (ELEV were identified by using high-performance liquid chromatography (HPLC and gas chromatography-mass spectroscopy (GC-MS analyses. Shade dried leaves were powdered and extracted with ethanol for analyses through HPLC to identify selected flavonoids and through GC-MS to identify other molecules. The HPLC analysis of ELEV showed the presence of gallic and caffeic acids as the major components at concentrations of 2.0 ppm and 0.1 ppm, respectively, as well as other components. GC-MS analysis revealed the presence of 3-eicosyne; 3,7,11,15-tetramethyl-2-hexadecen-1-ol; butanoic acid, 3-methyl-3,7-dimethyl-6-octenyl ester; phytol; 1,2-benzenedicarboxylic acid, diundecyl ester; 1-octanol, 2-butyl-; squalene; and 2H-pyran, 2-(7-heptadecynyloxy tetrahydro-derivative. Because pharmacopuncture is a new evolving natural mode that uses herbal extracts for treating patients with various ailments with minimum pain and maximum effect, the results of this study are particularly important and show that ELEV possesses a wide range of phytochemical constituents, as indicated above, as effective active principle molecules that can be used individually or in combination to treat patients with various diseases.

  11. Gas chromatography-mass spectrometry and high-performance liquid chromatography-diode array detection for dating of paper ink.

    Science.gov (United States)

    Díaz-Santana, Oscar; Vega-Moreno, Daura; Conde-Hardisson, Francisco

    2017-09-15

    An extraction and determination method is shown for the analysis of dyes and solvents present in two types of ballpoint pen inks that are deposited onto paper. Ink extracts are analysed using a combination of gas chromatography with mass spectrometry (GC-MS), and high-pressure liquid chromatography with photodiode array detection (HPLC-DAD), within a single sample extraction procedure. Seventeen solvents and thirteen dyes contained in two Montblanc ® inks (black and blue) were monitored for 45 months at monthly intervals, in order to determine variations in the concentrations of the compounds over time. We also studied the relative variations between different compounds and the generation of degradation products such as phenol. The concentration data obtained from these compounds during their exposure have been analysed and a multiple regression model is developed for each ink type that allows an estimate of the exposure time of the ink on paper with a maximum error of between 4 and 7 months. Copyright © 2017 Elsevier B.V. All rights reserved.

  12. Qualitative gas chromatography-mass spectrometry analyses using amines as chemical ionization reagent gases.

    Science.gov (United States)

    Little, James L; Howard, Adam S

    2013-12-01

    Ammonia is a very useful chemical ionization (CI) reagent gas for the qualitative analyses of compounds by positive ion gas chromatography-mass spectrometry (GCMS). The gas is readily available, inexpensive, and leaves no carbon contamination in the MS source. Compounds of interest to our laboratory typically yield abundant protonated or ammoniated species, which are indicative of a compound's molecular weight. Nevertheless, some labile compounds fragment extensively by substitution and elimination reactions and yield no molecular weight information. In these cases, a CI reagent gas mixture of methylamine in methane prepared dynamically was found to be very useful in obtaining molecular weight data. Likewise, deuterated ammonia and deuterated methylamine are useful CI reagent gases for determining the exchangeable protons in organic compounds. Deuterated methylamine CI reagent gas is conveniently prepared by dynamically mixing small amounts of methylamine with excess deuterated ammonia.

  13. Determination of Fatty Acid in Asparagus by Gas Chromatography

    Directory of Open Access Journals (Sweden)

    Zehra HAJRULAI-MUSLIU

    2016-05-01

    Full Text Available Asparagus contain a lot of macronutrients and micronutrients including folate, dietary fibre (soluble and insoluble and phenolic compounds. Also asparagus is a good source of unsaturated linoleic and linolenic fatty acids which are precursors for Eicosapentanoic acid (EPA and Docosahexanoic acid (DHA. Unsaturated fatty acids have important biological effects and they have important role in human health. The objective of this study was to analyze fatty acid composition of asparagus as a potential source of linoleic and linolenic acid - a precursor for EPA and DHA. For this reason we analyzed fifty seven samples of asparagus collected from the local market. We used AOAC 996.06 method and analyses were performed with gas chromatograph with flame-ionization detector (GC-FID. The highest concentration of fatty acid in the asparagus was linoleic acid (C18:2n6 which content in asparagus is 25.620±1.0%. Also, asparagus is good source of -linolenic fatty acid (C18:3n3 and content of this fatty acid in asparagus is 8.840±0.3%. The omega-6 to omega-3 (n6/n3 ratio in asparagus was 3.19. Polyunsaturated fatty acids (PUFAs were higher than monounsaturated fatty acids (MUFAs, and from saturated fatty acids, palmitic acid was most frequent with 24.324±1.0%. From our study we can conclude that asparagus is very good source of unsaturated fatty acids, especially linoleic and linolenic fatty acids.

  14. Quantitative analysis of abused drugs in physiological fluids by gas chromatography/chemical ionization mass spectrometry

    International Nuclear Information System (INIS)

    Foltz, R.L.

    1978-01-01

    Methods have been developed for quantitative analysis of commonly abused drugs in physiological fluids using gas chromatography/chemical ionization mass spectrometry. The methods are being evaluated in volunteer analytical and toxicological laboratories, and analytical manuals describing the methods are being prepared. The specific drug and metabolites included in this program are: Δ 9 -tetrahydrocannabinol, methadone, phencyclidine, methaqualone, morphine, amphetamine, methamphetamine, mescaline, 2,5-dimethoxy-4-methyl amphetamine, cocaine, benzoylecgonine, diazepam, and N-desmethyldiazepam. The current analytical methods utilize relatively conventional instrumentation and procedures, and are capable of measuring drug concentrations as low as 1 ng/ml. Various newer techniques such as sample clean-up by high performance liquid chromatography, separation by glass capillary chromatography, and ionization by negative ion chemical ionization are being investigated with respect to their potential for achieving higher sensitivity and specificity, as well as their ability to facilitate simultaneous analysis of more than one drug and metabolite. (Auth.)

  15. Gas chromatography x gas chromatography-time-of-flight mass spectrometry analysis and antibacterial activity of essential oil from Amomum xanthophlebium

    International Nuclear Information System (INIS)

    Masila, A.; Aminah, I.; Yaakob, W.A.; Nazlina, I.

    2011-01-01

    Essential oils of fresh leaves, stem, rhizomes and whole aromatic plants of Amomum xanthophlebium (Zingiberaceae) were obtained by hydro distillation. Percentage yields of the leaf, stem and whole plant oils were 0.0032, 0.0074 and 0.0021 % whereas the rhizome oil obtained was very little. Chemical components of each oil and their percentages were determined by Gas Chromatography x Gas Chromatography-Time-of-Flight Mass Spectrometry (GCxGC-TOFMS). Analysis of A. xanthophlebium oils showed that they were dominated by terpenes. Main components in the leaves were allo-aromadendrene (3.41 %), (±)-globulol (2.58 %) and rosifoliol (2.55 %); stem, α-terpineol (4.25 %), rosifoliol (2.41 %) and bingpian (2.27 %); rhizomes, viridiflorol (5.72 %), (±)-globulol (5.23 %) and α-cadinol (4.81 %); whole plants, eucalyptol (4.11 %), l-α-terpineol (2.88 %) and rosifoliol (2.82 %). The stem oil of A. xanthophlebium showed antibacterial activity against Gram-negative Escherichia coli and Gram-positive methicillin-resistant Staphylococcus aureus (MRSA) at the minimum inhibitory concentration of 80 mg/ ml. (author)

  16. Identification of key aromatic compounds in Congou black tea by PLSR with variable importance of projection scores and gas chromatography-mass spectrometry/gas chromatography-olfactometry.

    Science.gov (United States)

    Mao, Shihong; Lu, Changqi; Li, Meifeng; Ye, Yulong; Wei, Xu; Tong, Huarong

    2018-04-13

    Gas chromatography-olfactometry (GC-O) is the most frequently used method to estimate the sensory contribution of single odorant, but disregards the interactions between volatiles. In order to select the key volatiles responsible for the aroma attributes of Congou black tea (Camellia sinensis), instrumental, sensory and multivariate statistical approaches were applied. By sensory analysis, nine panelists developed 8 descriptors, namely, floral, sweet, fruity, green, roasted, oil, spicy, and off-odor. Linalool, (E)-furan linalool oxide, (Z)-pyran linalool oxide, methyl salicylate, β-myrcene, phenylethyl alcohol which identified from the most representative samples by GC-O procedure, were the essential aroma-active compounds in the formation of basic Congou black tea aroma. In addition, 136 volatiles were identified by gas chromatography-mass spectrometry (GC-MS), among which 55 compounds were determined as the key factors for the six sensory attributes by partial least-square regression (PLSR) with variable importance of projection (VIP) scores. Our results demonstrated that HS-SPME/GC-MS/GC-O was a fast approach for isolation and quantification aroma-active compounds. PLSR method was also considered to be a useful tool in selecting important variables for sensory attributes. These two strategies allowed us to comprehensively evaluate the sensorial contribution of single volatile from different perspectives, can be applied to related products for comprehensive quality control. This article is protected by copyright. All rights reserved.

  17. Odour-active compounds of Citrus deliciosa Tenore var. Caí essential oils detected by gas chromatography-mass spectrometry and gas chromatography-olfactometry

    Directory of Open Access Journals (Sweden)

    Manuel A. Minteguiaga

    2017-11-01

    Full Text Available Context: Mandarins are a complex taxonomic group including different species, cultivars and hybrids growing around the world being fruits greatly appreciated by the consumers. Citrus deliciosa Tenore var. Caí originates from Rio Grande do Sul State (Brazil and the fruit is characterised by its pleasant properties, especially its aroma. Aims: To evaluate the C. deliciosa cold-pressed essential oils, classified as “green”, “yellow” and “red” according to fruit maturity, and the one produced by distillation by gas chromatography-mass spectrometry (GC-MS and gas chromatography-olfactometry (GC-O. Methods: The essential oils aromatic quality was evaluated by GC-O through a panel of trained judges. The identification of the volatile compounds was performed by GC-MS and their quantification by GC-FID. Results: The chemical composition of the three types of cold-pressed essential oils was very similar. However, the distilled oil presented a higher concentration of oxygenated monoterpenes (mainly α-terpineol, 4-terpineol and sabinene hydrates. Herbaceous and floral aromatic notes were able to describe the “green” oil, while for the distilled oil wood and unpleasant notes were perceived. Conclusions: The cold-pressed oils did not show nor chemical, or aromatic differences, by the fruit maturity. The distilled oil was characterized by aromatic nuances making the oil less appreciated (inferior quality than the cold-pressed oil. Probably as consequence of artifacts formation during the distillation process.

  18. Comparison of aroma volatiles in commercial Merlot and Cabernet Sauvignon wines using gas chromatography-olfactometry and gas chromatography-mass spectrometry.

    Science.gov (United States)

    Gürbüz, Ozan; Rouseff, June M; Rouseff, Russell L

    2006-05-31

    Seventy-four aroma active compounds were observed in Merlot and Cabernet Sauvignon wines produced in California and Australia. Volatiles were sampled using solid phase microextraction and analyzed using time-intensity gas chromatography-olfactometry and gas chromatography-mass spectrometry (GC-MS). The most intense odorants were 3-methyl-1-butanol, 3-hydroxy-2-butanone, octanal, ethyl hexanoate, ethyl 2-methylbutanoate, beta-damascenone, 2-methoxyphenol, 4-ethenyl-2-methoxy-phenol, ethyl 3-methylbutanoate, acetic acid, and 2-phenylethanol. Aroma compounds were classified according to their aroma descriptor similarity and summed into nine distinct categories consisting of fruity, sulfury, caramel/cooked, spicy/peppery, floral, earthy, pungent/chemical, woody, and green/vegetative/fatty. Both Merlot and Cabernet Sauvignon wines were characterized by high fruity, caramel, green, and earthy aroma totals. Although there were distinct quantitative differences between Merlot and Cabernet wines, the relative aroma category profiles of the four wines were similar. Of the 66 volatiles identified by GC-MS, 28 were esters and 19 were minor alcohols. Between 81 and 88% of the total MS total ion chromatogram peak areas from each wine type were produced from only eight compounds: ethanol, ethyl octanoate, ethyl decanoate, ethyl acetate, 3-methyl-1-butanol, ethyl hexanoate, diethyl succinate, and 2-phenylethanol. Merlot wines from both Australia and California contained 4-5 times more ethyl octanoate than Cabernet Sauvignon wines from the same sources.

  19. Comparison of an Electronic Nose Based on Ultrafast Gas Chromatography, Comprehensive Two-Dimensional Gas Chromatography, and Sensory Evaluation for an Analysis of Type of Whisky

    Directory of Open Access Journals (Sweden)

    Paulina Wiśniewska

    2017-01-01

    Full Text Available Whisky is one of the most popular alcoholic beverages. There are many types of whisky, for example, Scotch, Irish, and American whisky (called bourbon. The whisky market is highly diversified, and, because of this, it is important to have a method which would enable rapid quality evaluation and authentication of the type of whisky. The aim of this work was to compare 3 methods: an electronic nose based on the technology of ultrafast gas chromatography (Fast-GC, comprehensive two-dimensional gas chromatography (GC × GC, and sensory evaluation. The selected whisky brands included 6 blended whiskies from Scotland, 4 blended whiskies from Ireland, and 4 bourbons produced in the USA. For data analysis, peak heights of chromatograms were used. The panelists who took part in sensory evaluations included 4 women and 4 men. The obtained data were analyzed by 2 chemometric methods: partial least squares discriminant analysis (PLS-DA and discrimination function analysis (DFA. E-nose and GC × GC allowed for differentiation between whiskies by type. Sensory analysis did not allow for differentiation between whiskies by type, but it allowed giving consumer preferences.

  20. Impact of gas chromatography and mass spectrometry combined with gas chromatography and olfactometry for the sex differentiation of Baccharis articulata by the analysis of volatile compounds.

    Science.gov (United States)

    Minteguiaga, Manuel; Umpiérrez, Noelia; Fariña, Laura; Falcão, Manuel A; Xavier, Vanessa B; Cassel, Eduardo; Dellacassa, Eduardo

    2015-09-01

    The Baccharis genus has more than 400 species of aromatic plants. However, only approximately 50 species have been studied in oil composition to date. From these studies, very few take into consideration differences between male and female plants, which is a significant and distinctive factor in Baccharis in the Asteraceae family. Baccharis articulata is a common shrub that grows wild in south Brazil, northern and central Argentina, Bolivia, Paraguay and Uruguay. It is considered to be a medicinal plant and is employed in traditional medicine. We report B. articulata male and female volatile composition obtained by simultaneous distillation-extraction technique and analyzed by gas chromatography with mass spectrometry. Also, an assessment of aromatic differences between volatile extracts was evaluated by gas chromatography with olfactometry. The results show a very similar chemical composition between male and female extracts, with a high proportion of terpene compounds of which β-pinene, limonene and germacrene D are the main components. Despite the chemical similarity, great differences in aromatic profile were found: male plant samples exhibited the strongest odorants in number and intensity of aromatic attributes. These differences explain field observations which indicate differences between male and female flower aroma, and might be of ecological significance in the attraction of pollinating insects. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  1. MRM screening/biomarker discovery with linear ion trap MS: a library of human cancer-specific peptides

    International Nuclear Information System (INIS)

    Yang, Xu; Lazar, Iulia M

    2009-01-01

    The discovery of novel protein biomarkers is essential in the clinical setting to enable early disease diagnosis and increase survivability rates. To facilitate differential expression analysis and biomarker discovery, a variety of tandem mass spectrometry (MS/MS)-based protein profiling techniques have been developed. For achieving sensitive detection and accurate quantitation, targeted MS screening approaches, such as multiple reaction monitoring (MRM), have been implemented. MCF-7 breast cancer protein cellular extracts were analyzed by 2D-strong cation exchange (SCX)/reversed phase liquid chromatography (RPLC) separations interfaced to linear ion trap MS detection. MS data were interpreted with the Sequest-based Bioworks software (Thermo Electron). In-house developed Perl-scripts were used to calculate the spectral counts and the representative fragment ions for each peptide. In this work, we report on the generation of a library of 9,677 peptides (p < 0.001), representing ~1,572 proteins from human breast cancer cells, that can be used for MRM/MS-based biomarker screening studies. For each protein, the library provides the number and sequence of detectable peptides, the charge state, the spectral count, the molecular weight, the parameters that characterize the quality of the tandem mass spectrum (p-value, DeltaM, Xcorr, DeltaCn, Sp, no. of matching a, b, y ions in the spectrum), the retention time, and the top 10 most intense product ions that correspond to a given peptide. Only proteins identified by at least two spectral counts are listed. The experimental distribution of protein frequencies, as a function of molecular weight, closely matched the theoretical distribution of proteins in the human proteome, as provided in the SwissProt database. The amino acid sequence coverage of the identified proteins ranged from 0.04% to 98.3%. The highest-abundance proteins in the cellular extract had a molecular weight (MW)<50,000. Preliminary experiments have

  2. Determination of 4-Chloroindole-3-Acetic Acid Methyl Ester in Lathyrus Vicia and Pisum by Gas Chromatography - Mass Spectrometry

    DEFF Research Database (Denmark)

    Engvild, Kjeld Christensen; Egsgaard, Helge; Larsen, Elfinn

    1980-01-01

    4-Chloroindole-3-acetic acid methyl ester was identified unequivocally in Lathyrus latifolius L., Vicia faba L. and Pisum sativum L. by thin layer chromatography, gas chromatography and mass spectrometry. The gas chromatographic system was able to separate underivatized chloroindole-3-acetic acid...... methyl ester isomers. The quantitative determination of 4-chloroindole-3-acetic acid methyl ester in immature seeds of these three species was performed by gas chromatography – mass spectrometry using deuterium labelled 4-chloro-indole-3-acetic acid methyl ester as an internal standard. P. sativum...

  3. Assessment of pesticide residues in some fruits using gas chromatography coupled with micro electron capture detector

    International Nuclear Information System (INIS)

    Latif, Y.; Sherazi, S.T.H.; Bhanger, M.I.

    2011-01-01

    A very sensitive analytical method for the determination of 26 pesticides in some fruits based on solid phase extraction (SPE) cleanup was developed using gas chromatography (GC) coupled with micro electron capture detector (mu ECD). The identity of the pesticides was confirmed by gas chromatography mass spectroscopy (GC-MS) using selected ion monitoring (SIM) mode. Ethyl acetate was used as a solvent for the extraction of pesticide residues with assistance of sonication. For cleanup an octadecyl, C18 SPE column was used. A linear response of mu ECD was observed for all pesticides with good correlation coefficients (>0.9992). Proposed method was successfully applied for the determination of pesticide residues in the orange, apple, and grape fruits. Average recoveries achieved for all of the pesticides at fortification levels of 0.05, 1.0 and 2.0 mu g g/sup -1/ in analyzed fruits were above 90% with relative standard deviations (RSD) less than 6%. (author)

  4. Determination of Alkyl Methanesulfonates in Doxazosin Mesylate by Gas Chromatography-mass Spectrometer.

    Science.gov (United States)

    Sitaram, C; Rupakula, R B; Reddy, B N; Sastry, C S P

    2011-01-01

    High sensitive rapid gas chromatography-mass spectrometry method for the determination of four carcinogenic alkyl methanesulfonates viz. methyl methanesulfonate, ethyl methanesulfonate, isopropyl methanesulfonate and n-butyl methanesulfonate in doxazosin mesylate has been presented by using selective ion monitoring mode. The optimum separation was achieved between methyl methanesulfonate, ethyl methanesulfonate, isopropyl methanesulfonate and n-butyl methanesulfonate on a DB-5 (30 m×0.32 mm×1.0 μm) capillary column under programming temperature. Acetonitrile, water and ammonia (90:9:1 v/v/v) mixture was used as diluent. Various factors involved in the gas chromatography-mass spectrometry method development are also presented. This method was validated as per International Conference on Harmonization guidelines. The limit of quantitation of methyl methanesulfonate, ethyl methanesulfonate, isopropyl methanesulfonate and n-butyl methanesulfonate is 6 ppm with respect to 30 mg/ml of doxazosin mesylate.

  5. Direct measurement of Kryptofix 2.2.2 in 18F-FDG by gas chromatography

    International Nuclear Information System (INIS)

    Hua Ning; Chen Liguang

    2007-01-01

    Kryptofix 2.2.2 in 18 F-FDG preparation is analized by gas chromatography coupled with OV-101 capillary column, and nitrogen-selective detector (NPD) and FID. Its retention time is 2.4 min from the column, and detected at the levels as low as 0.50 mg/L; the average residual of 30 normal batchs are 1.10 ± 0.15 mg/L (n=30). Direct measurement of Kryptofix 2.2.2 in routine 18 F-FDG preparation is effective using Gas Chromatography with a high sensitivity (50 times better than TLC method) for the daily quality control of 18 F-FDG. (authors)

  6. Determination of ketone bodies in blood by headspace gas chromatography-mass spectrometry

    DEFF Research Database (Denmark)

    Holm, Karen Marie Dollerup; Linnet, Kristian; Rasmussen, Brian Schou

    2010-01-01

    A gas chromatography-mass spectrometry (GC-MS) method for determination of ketone bodies (ß-hydroxybutyrate, acetone, and acetoacetate) in blood is presented. The method is based on enzymatic oxidation of D-ß-hydroxybutyrate to acetoacetate, followed by decarboxylation to acetone, which was quant......A gas chromatography-mass spectrometry (GC-MS) method for determination of ketone bodies (ß-hydroxybutyrate, acetone, and acetoacetate) in blood is presented. The method is based on enzymatic oxidation of D-ß-hydroxybutyrate to acetoacetate, followed by decarboxylation to acetone, which...... from 98 to 107%, demonstrating the suitability of the method for measuring ketone bodies over a wide concentration range. The method has been applied to cases in which ketoacidosis was suspected as the cause of death in diabetics or chronic alcoholics, as well as to cases in which another cause...

  7. Analysis of Petroleum Products in Fire Debris Residues by Gas Chromatography: A Literature Review

    Directory of Open Access Journals (Sweden)

    Gurvinder Singh Bumbrah

    2017-06-01

    Full Text Available This review gives a brief overview of developments in the analysis of petroleum products (PP in fire debris residues (FDR by gas chromatography (GC. The review covers different aspects of analysis such as the substrates involved, isolation procedures, column and mobile phase used, and subsequent detection in tabular form. This paper covers detection of PP such as petrol, kerosene, and diesel in various types’ of samples of interest to fire debris analysts. Solid phase microextraction is most frequently used along with gas chromatography-mass spectrometry (GC-MS for the extraction and identification of PP from FDR. Chemometric tools should be used to improve the significance and reliability of results obtained from the analysis of FDR. However, the potential utility of portable GC-MS in fire debris analysis cannot be ignored, and its proper development and validation is required before using it for this purpose.

  8. Quantification of carbonate by gas chromatography-mass spectrometry.

    Science.gov (United States)

    Tsikas, Dimitrios; Chobanyan-Jürgens, Kristine

    2010-10-01

    Carbon dioxide and carbonates are widely distributed in nature, are constituents of inorganic and organic matter, and are essential in vegetable and animal organisms. CO(2) is the principal greenhouse gas in the atmosphere. In human blood, CO(2)/HCO(3)(-) is an important buffering system. Quantification of bicarbonate and carbonate in inorganic and organic matter and in biological fluids such as blood or blood plasma by means of the GC-MS technology has been impossible so far, presumably because of the lack of suitable derivatization reactions to produce volatile and thermally stable derivatives. Here, a novel derivatization reaction is described for carbonate that allows for its quantification in aqueous alkaline solutions and alkalinized plasma and urine. Carbonate in acetonic solutions of these matrices (1:4 v/v) and added (13)C-labeled carbonate for use as the internal standard were heated in the presence of the derivatization agent pentafluorobenzyl (PFB) bromide for 60 min and 50 °C. Investigations with (12)CO(3)(2-), (13)CO(3)(2-), (CH(3))(2)CO, and (CD(3))(2)CO in alkaline solutions and GC-MS and GC-MS/MS analyses under negative-ion chemical ionization (NICI) or electron ionization (EI) conditions of toluene extracts of the reactants revealed formation of two minor [i.e., PFB-OCOOH and O=CO(2)-(PFB)(2)] and two major [i.e., CH(3)COCH(2)-C(OH)(OPFB)(2) and CH(3)COCH=C(OPFB)(2)] carbonate derivatives. The latter have different retention times (7.9 and 7.5 min, respectively) but virtually identical EI and NICI mass spectra. It is assumed that CH(3)COCH(2)-C(OH)(OPFB)(2) is formed from the reaction of the carbonate dianion with two molecules of PFB bromide to form the diPFB ester of carbonic acid, which further reacts with one molecule of acetone. Subsequent loss of water finally generates the major derivative CH(3)COCH=C(OPFB)(2). This derivatization reaction was utilized to quantify total CO(2)/HCO(3)(-)/CO(3)(2-) (tCO(2)) in human plasma and urine by GC

  9. Chemotaxonomic Characterization of Microorganisms by Capillary Gas Chromatography-Mass Spectrometry

    Science.gov (United States)

    1988-06-01

    indirectly detecting differences in carbohydrate composition ( Lancefield grouping ). The group B-specific polysaccharide consists of a backbcne of...carbohydrate pyrolysis product generated from the glucitol moiety. We have further used pattern recognition to differentiate several Lancefield groups of... Group A and Group B Streptococci by Pyrolysis Gas Chromatography- Mass Spectrometry," A- alytical Chemistry, 59, 1410-1413 (1987). S. L. Morgan, M. D

  10. Analysis of volatile organic compounds by cryogenic oven trapping gas chromatography

    OpenAIRE

    渡部, 加奈子; 石井, 晃; 李, 暁鵬; 鈴木, 修; 鈴木, 加奈子

    2000-01-01

    Recently, a microcomputer-controlled device for lowering oven temperature below 0℃ has become available for new types of gas chromatography (GC) instruments. This device was originally designed for rapid cooling of an oven to reduce the time for analysis. In our laboratories, we are using it for trapping volatile organic compounds (VOCs) inside a capillary column at cryogenic oven temperatures; as much as 5 ml of headspace vapor can be injected into a medium-bore capillary column without any ...

  11. Micromethod for measuring hexachlorophene in whole blood by gas-liquid chromatography.

    Science.gov (United States)

    Dodson, W E; Tyrala, E E; Hillman, R E

    1977-06-01

    We describe a micromethod for measuring hexachlorophene by use of gas-liquid chromatography with a 63Ni electron capture detector. The procedure requires 100 micronl of blood for extractions of hexachlorophene, and dichlorophene is added as an internal standard. CV is 3.4% over the concentration range of 500 to 1300 microng of hexachlorophene per liter of whole blood. This procedure permits repeated measurements of hexachlorophene in newborns who are being washed with soap containing hexachlorophene.

  12. Determination of Alkyl Methanesulfonates in Doxazosin Mesylate by Gas Chromatography-mass Spectrometer

    OpenAIRE

    Sitaram, C.; Rupakula, R. B.; Reddy, B. N.; Sastry, C. S. P

    2011-01-01

    High sensitive rapid gas chromatography-mass spectrometry method for the determination of four carcinogenic alkyl methanesulfonates viz. methyl methanesulfonate, ethyl methanesulfonate, isopropyl methanesulfonate and n-butyl methanesulfonate in doxazosin mesylate has been presented by using selective ion monitoring mode. The optimum separation was achieved between methyl methanesulfonate, ethyl methanesulfonate, isopropyl methanesulfonate and n-butyl methanesulfonate on a DB-5 (30 m×0.32 mm×1...

  13. Microfluidic Columns with Nanotechnology-Enabled Stationary Phases for Gas Chromatography

    OpenAIRE

    Shakeel, Hamza

    2015-01-01

    Advances in micro-electro-mechanical-systems (MEMS) along with nanotechnology based methods have enabled the miniaturization of analytical chemistry instrumentation. The broader aim is to provide a portable, low-cost, and low-power platform for the real-time detection and identification of organic compounds in a wide variety of applications. A benchtop gas chromatography (GC) system is considered a gold standard for chemical analysis by analytical chemists. Similarly, miniaturization of key G...

  14. Determination of Carboxypeptidase Activity in Clinical Pathogens by Gas Chromatography?Mass Spectrometry

    OpenAIRE

    Lough, Fraser; Perry, John D.; Stanforth, Stephen P.; Dean, John R.

    2016-01-01

    ABSTRACT A novel method for the determination of benzoic acid has been employed to identify carboxypeptidase activities in clinically relevant pathogens. Benzoic acid was determined after chemical derivatization by gas chromatography?mass spectrometry (GC?MS). N-Benzoyl amino acid substrates were evaluated for the detection of carboxypeptidase activities in a number of clinical pathogens. Upon enzymatic hydrolysis of these substrates, benzoic acid was produced which was detected by extraction...

  15. Analysis of Bacterial Vaginosis-Related Amines in Vaginal Fluid by Gas Chromatography and Mass Spectrometry

    OpenAIRE

    Wolrath, Helen; Forsum, Urban; Larsson, P. G.; Borén, Hans

    2001-01-01

    The presence of various amines in vaginal fluid from women with malodorous vaginal discharge has been reported before. The investigations have used several techniques to identify the amines. However, an optimized quantification, together with a sensitive analysis method in connection with a diagnostic procedure for vaginal discharge, including the syndrome of bacterial vaginosis, as defined by the accepted “gold standard,” has not been done before. We now report a sensitive gas chromatographi...

  16. Method for analysis of heavy sulphur compounds using gas chromatography with flame photometric detection

    OpenAIRE

    Moreira, N.; Pinho, P. Guedes de; Vasconcelos, I.

    2004-01-01

    A method for analysis of heavy sulphur compounds in wines, based on gas chromatography (GC) with flame photometric detection, is reported. Wine samples preparation includes a dichloromethane liquid–liquid extraction followed by concentration under a nitrogen atmosphere. The extracted fraction was also analysed by GC–mass spectrometry. The method enables high recovery of sulphur compounds in wine and satisfies the requirements of repeatability and sensitivity. Applications of the meth...

  17. Rapid mass spectrometry analysis of a rectilinear ion trap by continuous secular frequency scanning.

    Science.gov (United States)

    Huo, Xinming; Chen, Jin; Tang, Fei; Yao, Tongtong; Piao, Shiyun; Ni, Kai; Wang, Xiaohao

    2017-06-30

    Secular frequency scanning is a mass spectrometry (MS) analysis method in which the frequency of the auxiliary alternating current (AC) signal is scanned. It has low requirements for radio-frequency (RF) power, which is beneficial for the miniaturization of the mass spectrometer. In this study, the MS performance in the reverse secular frequency scanning (RSFS) mode is optimized for a rectilinear ion trap (RIT), and a method for rapid MS analysis using continuous secular frequency scanning (CSFS) is proposed. A RIT mass spectrometer with an auxiliary AC frequency scanning function was built. The resolution, tandem mass spectrometry (MS/MS) and quantitation capability in the RSFS mode were characterized and optimized. Operation in the CSFS mode was then performed by scanning the frequency of the auxiliary AC signal continuously and periodically while maintaining the RF signal and the front Z electrode in the ion injection state, so that the ion injection and cooling were performed at the same time as the mass analysis. With this system, the RSFS mode achieved unit mass resolution at 332 Th, and the MS/MS analysis was completed without changing the RF amplitude at q = 0.4583 for reserpine. The limit of quantitation for imatinib was about 250 ng/mL with the determination coefficient R 2  = 0.9981. In the CSFS mode, a single analysis cycle of less than 20 ms could be achieved, which is 14 times faster than the traditional sweep modes. In addition, 100% ion utilization can theoretically be achieved in the CSFS mode. The CSFS mode is different from the traditional phased sequential operation mode of an ion trap mass spectrometer. By periodic scanning of the auxiliary AC frequency while maintaining ion injection, it is possible to improve the analysis efficiency of the mass spectrometer, which has the prospect of useful application in the field of rapid MS monitoring. Copyright © 2017 John Wiley & Sons, Ltd. Copyright © 2017 John Wiley & Sons, Ltd.

  18. Determination of gas phase triacetone triperoxide with aspiration ion mobility spectrometry and gas chromatography-mass spectrometry.

    Science.gov (United States)

    Räsänen, Riikka-Marjaana; Nousiainen, Marjaana; Peräkorpi, Kaleva; Sillanpää, Mika; Polari, Lauri; Anttalainen, Osmo; Utriainen, Mikko

    2008-08-08

    Aspiration ion mobility spectrometry (IMS) has been used for the first time to screen 3,3,6,6,9,9-hexamethyl-1,2,4,5,7,8-hexaoxacyclononane explosive, the most commonly known as triacetone triperoxide (TATP). Gaseous TATP was generated from synthesized solid compound, sublimed and directed to a portable chemical detection system comprised of an aspiration-type IMS detector and six semiconductor sensors. Different unknown TATP gas phase concentrations were produced and corresponding IMS and semiconductor responses were measured. The experimental concentrations were determined by gas chromatography-mass spectrometry (GC-MS). The results evidenced that the monitored compound in the gas phase was TATP. In addition, the determined TATP concentrations and corresponding IMS intensities showed that the IMS response values were proportional to the measured TATP concentrations.

  19. Sub-to super-ambient temperature programmable microfabricated gas chromatography column

    Science.gov (United States)

    Robinson, Alex L.; Anderson, Lawrence F.

    2004-03-16

    A sub- to super-ambient temperature programmable microfabricated gas chromatography column enables more efficient chemical separation of chemical analytes in a gas mixture by combining a thermoelectric cooler and temperature sensing on the microfabricated column. Sub-ambient temperature programming enables the efficient separation of volatile organic compounds and super-ambient temperature programming enables the elution of less volatile analytes within a reasonable time. The small heat capacity and thermal isolation of the microfabricated column improves the thermal time response and power consumption, both important factors for portable microanalytical systems.

  20. [Application of gas chromatography in the identification of Enterobacter cloacae, Enterobacter aerogenes, and Enterobacter agglomerans].

    Science.gov (United States)

    Robles Valderrama, E; Ramírez García, P; González Arreaga, M E; Sáinz Morales, M G; Martínez Rodríguez, B; Durán Díaz, A; Chávez Ramírez, D

    1999-01-01

    Enterobacter cloacae, Enterobacter aerogenes and Enterobacter agglomerans were identified using gas chromatography as a substitution of the traditional techniques. Their acid methyl esters profiles were determined using a gas chromatograph Hewlett Packard 5890A and a RSL-150 heliflex capillary column. A total of 120 samples were analyzed from reference strains (ATCC 13047, 13048, 27155) and environmental isolations, eleven fatty acids were included in the profiles from which cis-9, 10-methyleneoctadecanoic acid (peak 24), cis-9-hexadecenoic acid (peak 14), octadecanoic acid (peak 23) and dodecanoic acid (peak 3), were the most important for the differentiation of the three species analyzed.

  1. Behavior of macroporous vinyl silica and silica monolithic columns in high pressure gas chromatography.

    Science.gov (United States)

    Maniquet, Adrien; Bruyer, Nicolas; Raffin, Guy; Baco-Antionali, Franck; Demesmay, Claire; Dugas, Vincent; Randon, Jérôme

    2017-06-30

    80% vinyltrimethoxysilane-based hybrid silica monoliths (80-VTMS), which have been initially developed for separation in reversed-phase liquid chromatography, have been investigated in high pressure gas chromatography separations (carrier gas pressure up to 60bar) and compared to silica monolithic columns. The behavior of both silica and 80-VTMS monolithic columns was investigated using helium, nitrogen and carbon dioxide as carrier gas. The efficiency of 80-VTMS monolithic columns was shown to vary differently than silica monolithic columns according to the temperature and the carrier gas used. Carrier gas nature was a significant parameter on the retention for both silica and vinyl columns in relation to its adsorption onto the stationary phase in such high pressure conditions. The comparison of retention and selectivity between 80-VTMS monoliths and silica was performed under helium using the logarithm of the retention factor according to the number of carbon atoms combined to Kovats indexes. The very good performances of these columns were demonstrated, allowing the separation of 8 compounds in less than 1min. Copyright © 2017 Elsevier B.V. All rights reserved.

  2. Direct solid-phase microextraction combined with gas and liquid chromatography for the determination of lidocaine in human urine

    NARCIS (Netherlands)

    Koster, E.H M; Hofman, N.S K; de Jong, G.J.

    Solid-phase microextraction (SPME) has been combined with gas chromatography (GC) and liquid chromatography (LC) for the determination of lidocaine in human urine. A polydimethylsiloxane (PDMS) coated fibre was directly immersed into buffered urine. Extraction conditions such as time, pH, ionic

  3. Preventive doping control analysis: Liquid and gas chromatography time-to-flight mass spectrometry for detection of designer steriods

    NARCIS (Netherlands)

    Georgakopoulos, C.G.; Vonaparti, A.; Stamou, M.; Kiousi, P.; Lyris, E.; Angelis, Y.S.; Tsoupras, G.; Wuest, B.; Nielen, M.W.F.; Panderi, I.; Koupparis, M.

    2007-01-01

    A new combined doping control screening method for the analysis of anabolic steroids in human urine using liquid chromatography/electrospray ionization orthogonal acceleration time-of-flight mass spectrometry (LCoaTOFMS) and gas chromatography/electron ionization orthogonal acceleration

  4. Ion trap measurement of U64+ x-ray transition spectra

    International Nuclear Information System (INIS)

    Del Grande, N.K.; Beiersdorfer, P.; Henderson, J.R.; Osterheld, A.L.; Scofield, J.H.; Swenson, J.K.

    1990-09-01

    Highly-charged uranium ions with a dominant nickel-like component (U 64+ ) were produced using the Electron Beam Ion Trap (EBIT) with an electron bombardment energy of 7.4 keV. A comparison of the measured n=4 to n=3 x-ray transition spectra with calculations for U 64+ gave excellent qualitative agreement. The low-energy region of the 4-3 spectrum for the Ni-like ions was characterized by a strong electric quadrupole 4s-3d transition, about as large as the leading dipole 4f-3d transition, which tagged the abundance of U 64+ ions. High resolution spectroscopy was used to measure 4f-3d transition energies for ten charge states: U 60+ -U 69+ excited by 6.4-8.9 keV electrons. The ionization balance for 8.9 keV electron excitation was mostly from five charge states: U 64+ -U 68+ in qualitative agreement with a separate analysis of extracted ions. 16 refs., 4 figs., 3 tabs

  5. MSM, an Efficient Workflow for Metabolite Identification Using Hybrid Linear Ion Trap Orbitrap Mass Spectrometer

    Science.gov (United States)

    Cho, Robert; Huang, Yingying; Schwartz, Jae C.; Chen, Yan; Carlson, Timothy J.; Ma, Ji

    2012-05-01

    Identification of drug metabolites can often yield important information regarding clearance mechanism, pharmacologic activity, or toxicity for drug candidate molecules. Additionally, the identification of metabolites can provide beneficial structure-activity insight to help guide lead optimization efforts towards molecules with optimal metabolic profiles. There are challenges associated with detecting and identifying metabolites in the presence of complex biological matrices, and new LC-MS technologies have been developed to meet these challenges. In this report, we describe the development of an experimental approach that applies unique features of the hybrid linear ion trap Orbitrap mass spectrometer to streamline in vitro and in vivo metabolite identification experiments. The approach, referred to as MSM, utilizes multiple collision cells, dissociation methods, mass analyzers, and detectors. With multiple scan types and different dissociation modes built into one experimental method, along with flexible post-acquisition analysis options, the MSM workflow offers an attractive option to fast and reliable identification of metabolites in different kinds of in vitro and in vivo samples. The MSM workflow was successfully applied to metabolite identification analysis of verapamil in both in vitro rat hepatocyte incubations and in vivo rat bile samples.

  6. X-Ray Measurements Using a Microcalorimeter on an Electron Beam Ion Trap

    International Nuclear Information System (INIS)

    Silver, E.; Brickhouse, N. S.; Chen, G. X.; Kirby, K.; Gillaspy, J. D.; Tan, J. N.; Pomeroy, J. M.; Laming, J. M.

    2007-01-01

    The X-ray telescopes and spectrometers flown on Chandra and XMM-Newton are returning exciting new data from a wide variety of cosmic sources such as stellar coronae, supernova remnants, galaxies, clusters of galaxies, active galactic nuclei and X-ray binaries. To achieve the best scientific interpretation of the data from these and future spectroscopic missions and related ground-based observations, theoretical calculations and plasma models must be verified or modified by the results obtained from measurements in the laboratory. Such measurements are the focus of several laboratory astrophysics programs that use an electron beam ion trap (EBIT) to simulate astrophysical plasma conditions. Here we describe our recent spectroscopic measurements of neon-like iron and nickel using a microcalorimeter on the EBIT at the National Institute of Standards (NIST). We obtain values for the intensity ratios of the well-known lines emitted by these ions and compare the results with new large scale electron-ion scattering calculations. Additional details about our laboratory astrophysics work can be found in some earlier papers

  7. Determination of 48 fragrance allergens in toys using GC with ion trap MS/MS.

    Science.gov (United States)

    Lv, Qing; Zhang, Qing; Li, Wentao; Li, Haiyu; Li, Pi; Ma, Qiang; Meng, Xianshuang; Qi, Meiling; Bai, Hua

    2013-11-01

    This paper presents a method for the simultaneous determination of 48 fragrance allergens in four types of toys (plastic toys, play clays, plush toys, and paper toys) based on GC with ion trap MS/MS. Compared with single-stage MS, MS/MS is superior in terms of the qualification and quantification of a large range of compounds in complicated matrices. Procedures for extraction and purification were optimized for each toy type. The method proved to be linear over a wide range of concentrations for all analytes with correlation coefficients between 0.9768 and 0.9999. Validation parameters, namely, LODs and LOQs, ranged from 0.005-5.0 and from 0.02-20 mg/kg, respectively. Average recoveries of target compounds (spiked at three concentration levels) were in the range of 79.5-109.1%. Intraday and interday repeatabilities of the proposed method varied from 0.7-10.5% and from 3.1-13.4%, respectively. The proposed method was used to monitor fragrance allergens in commercial toy products. Our findings indicate that this method is an accurate and effective technique for analyzing fragrance allergens in materials composed of complex components. © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  8. Oligosaccharide sequences in Quillaja saponins by electrospray ionization ion trap multiple-stage mass spectrometry.

    Science.gov (United States)

    Broberg, Susanna; Nord, Lars I; Kenne, Lennart

    2004-06-01

    Ten different samples with 13 previously identified saponin structures from Quillaja saponaria Molina were investigated by electrospray ionization ion trap multiple-stage mass spectrometry (ESI-ITMS(n)) in positive and negative ion modes. Both positive and negative ion mode MS(1)-MS(4) spectra were analyzed, showing that structural information on the two oligosaccharide parts in the saponin can be obtained from positive ion mode spectra whereas negative ion mode spectra mainly gave information on one of the oligosaccharide parts. Analysis of MS(1)-MS(4) spectra identified useful key fragment ions important for the structural elucidation of Quillaja saponins. A flowchart involving a stepwise procedure based on key fragments from MS(1)-MS(3) spectra was constructed for the identification of structural elements in the saponin. Peak intensity ratios in MS(3) spectra were found to be correlated with structural features of the investigated saponins and are therefore of value for the identification of terminal monosaccharide residues. Copyright 2004 John Wiley & Sons, Ltd.

  9. The XRS microcalorimeter spectrometer at the Livermore Electron Beam Ion Trap

    Energy Technology Data Exchange (ETDEWEB)

    Porter, F S; Beiersdorfer, P; Boyce, K; Brown, G V; Chen, H; Gygax, J; Kahn, S M; Kelley, R; Kilbourne, C A; Magee, E; Thorn, D B

    2007-08-22

    NASA's X-ray Spectrometer (XRS) microcalorimeter instrument has been operating at the Electron Beam Ion Trap (EBIT) facility at Lawrence Livermore National Laboratory since July of 2000. The spectrometer is currently undergoing its third major upgrade to become an easy to use, extremely high performance instrument for a broad range of EBIT experiments. The spectrometer itself is broadband, capable of simultaneously operating from 0.1 to 12 keV and has been operated at up to 100 keV by manipulating its operating conditions. The spectral resolution closely follows the spaceflight version of the XRS, beginning at 10 eV FWHM at 6 keV in 2000, upgraded to 5.5 eV in 2003, and will hopefully be {approx}3.8 eV in the Fall of 2007. Here we review the operating principles of this unique instrument, the extraordinary science that has been performed at EBIT over the last 6 years, and prospects for future upgrades. Specifically we discuss upgrades to cover the high-energy band (to at least 100 keV) with a high quantum efficiency detector, and prospects for using a new superconducting detector to reach 0.8 eV resolution at 1 keV, and 2 eV at 6 keV with high counting rates.

  10. Controlling trapping potentials and stray electric fields in a microfabricated ion trap through design and compensation

    International Nuclear Information System (INIS)

    Charles Doret, S; Amini, Jason M; Wright, Kenneth; Volin, Curtis; Killian, Tyler; Ozakin, Arkadas; Denison, Douglas; Hayden, Harley; Pai, C-S; Slusher, Richart E; Harter, Alexa W

    2012-01-01

    Recent advances in quantum information processing with trapped ions have demonstrated the need for new ion trap architectures capable of holding and manipulating chains of many (>10) ions. Here we present the design and detailed characterization of a new linear trap, microfabricated with scalable complementary metal-oxide-semiconductor (CMOS) techniques, that is well-suited to this challenge. Forty-four individually controlled dc electrodes provide the many degrees of freedom required to construct anharmonic potential wells, shuttle ions, merge and split ion chains, precisely tune secular mode frequencies, and adjust the orientation of trap axes. Microfabricated capacitors on dc electrodes suppress radio-frequency pickup and excess micromotion, while a top-level ground layer simplifies modeling of electric fields and protects trap structures underneath. A localized aperture in the substrate provides access to the trapping region from an oven below, permitting deterministic loading of particular isotopic/elemental sequences via species-selective photoionization. The shapes of the aperture and radio-frequency electrodes are optimized to minimize perturbation of the trapping pseudopotential. Laboratory experiments verify simulated potentials and characterize trapping lifetimes, stray electric fields, and ion heating rates, while measurement and cancellation of spatially-varying stray electric fields permits the formation of nearly-equally spaced ion chains. (paper)

  11. MATS and LaSpec: High-precision experiments using ion traps and lasers at FAIR

    Science.gov (United States)

    Rodríguez, D.; Blaum, K.; Nörtershäuser, W.; Ahammed, M.; Algora, A.; Audi, G.; Äystö, J.; Beck, D.; Bender, M.; Billowes, J.; Block, M.; Böhm, C.; Bollen, G.; Brodeur, M.; Brunner, T.; Bushaw, B. A.; Cakirli, R. B.; Campbell, P.; Cano-Ott, D.; Cortés, G.; Crespo López-Urrutia, J. R.; Das, P.; Dax, A.; de, A.; Delheij, P.; Dickel, T.; Dilling, J.; Eberhardt, K.; Eliseev, S.; Ettenauer, S.; Flanagan, K. T.; Ferrer, R.; García-Ramos, J.-E.; Gartzke, E.; Geissel, H.; George, S.; Geppert, C.; Gómez-Hornillos, M. B.; Gusev, Y.; Habs, D.; Heenen, P.-H.; Heinz, S.; Herfurth, F.; Herlert, A.; Hobein, M.; Huber, G.; Huyse, M.; Jesch, C.; Jokinen, A.; Kester, O.; Ketelaer, J.; Kolhinen, V.; Koudriavtsev, I.; Kowalska, M.; Krämer, J.; Kreim, S.; Krieger, A.; Kühl, T.; Lallena, A. M.; Lapierre, A.; Le Blanc, F.; Litvinov, Y. A.; Lunney, D.; Martínez, T.; Marx, G.; Matos, M.; Minaya-Ramirez, E.; Moore, I.; Nagy, S.; Naimi, S.; Neidherr, D.; Nesterenko, D.; Neyens, G.; Novikov, Y. N.; Petrick, M.; Plaß, W. R.; Popov, A.; Quint, W.; Ray, A.; Reinhard, P.-G.; Repp, J.; Roux, C.; Rubio, B.; Sánchez, R.; Schabinger, B.; Scheidenberger, C.; Schneider, D.; Schuch, R.; Schwarz, S.; Schweikhard, L.; Seliverstov, M.; Solders, A.; Suhonen, M.; Szerypo, J.; Taín, J. L.; Thirolf, P. G.; Ullrich, J.; van Duppen, P.; Vasiliev, A.; Vorobjev, G.; Weber, C.; Wendt, K.; Winkler, M.; Yordanov, D.; Ziegler, F.

    2010-05-01

    Nuclear ground state properties including mass, charge radii, spins and moments can be determined by applying atomic physics techniques such as Penning-trap based mass spectrometry and laser spectroscopy. The MATS and LaSpec setups at the low-energy beamline at FAIR will allow us to extend the knowledge of these properties further into the region far from stability. The mass and its inherent connection with the nuclear binding energy is a fundamental property of a nuclide, a unique “fingerprint”. Thus, precise mass values are important for a variety of applications, ranging from nuclear-structure studies like the investigation of shell closures and the onset of deformation, tests of nuclear mass models and mass formulas, to tests of the weak interaction and of the Standard Model. The required relative accuracy ranges from 10-5 to below 10-8 for radionuclides, which most often have half-lives well below 1 s. Substantial progress in Penning trap mass spectrometry has made this method a prime choice for precision measurements on rare isotopes. The technique has the potential to provide high accuracy and sensitivity even for very short-lived nuclides. Furthermore, ion traps can be used for precision decay studies and offer advantages over existing methods. With MATS (Precision Measurements of very short-lived nuclei using an A_dvanced Trapping System for highly-charged ions) at FAIR we aim to apply several techniques to very short-lived radionuclides: High-accuracy mass measurements, in-trap conversion electron and alpha spectroscopy, and trap-assisted spectroscopy. The experimental setup of MATS is a unique combination of an electron beam ion trap for charge breeding, ion traps for beam preparation, and a high-precision Penning trap system for mass measurements and decay studies. For the mass measurements, MATS offers both a high accuracy and a high sensitivity. A relative mass uncertainty of 10-9 can be reached by employing highly-charged ions and a non

  12. Multiresidue analysis of pesticides in traditional Chinese medicines using gas chromatography - negative chemical ionization tandem mass spectrometry

    Science.gov (United States)

    In this study, a residue analysis method for the simultaneous determination of 107 pesticides in the traditional Chinese medicines (TCMs), Angelica sinensis, Angelica dahurica, Leonurus heterophyllus Sweet, Pogostemon cablin, and Lonicera japonica Thunb, was developed using gas chromatography couple...

  13. Can the biogenicity of Europa's surfical sulfur be tested simultaneously with penetrators and ion traps?

    Science.gov (United States)

    Chela-Flores, J.; Bhattacherjee, A. B.; Dudeja, S.; Kumar, N.; Seckbach, J.

    2009-04-01

    We suggest a biogenic interpretation of the sulfur patches on the Europan icy surface. This hypothesis is testable by LAPLACE, or a later mission, in which the instrumentation on board are penetrators, or ion traps, with component selection including miniaturized mass spectrometry. The argument in favor of such instrumentation and component selection is as follows: Extreme environments with microbes can act as models for extraterrestrial life (Seckbach et al., 2008). Suggestions have ranged from Venusian environments (Sagan, 1967, Seckbach and Libby, 1970) to Mars (Grilli Caiola and Billi, 2007). Active photosynthetic microbial communities are found on Antarctica, both in and on ice, in fresh water, in saline lakes and streams and within rocks. In the dry valley lakes of Antarctica close to the McMurdo Base, microbial mats are known to selectively remove a huge quantity of sulfur (Parker et al., 1982). Lake Vostok in Antarctica possesses a perennially thick (3 to 4 km) ice-cover that precludes photosynthesis, thus making this subglacial environment a good model system for determining how a potential Europan biota might emerge, evolve and distribute itself. Jupiter's moon Europa may harbor a subsurface water ocean, which lies beneath an ice layer that might be too thick to allow photosynthesis, just as in Lake Vostok. However, disequilibrium chemistry driven by charged particles from Jupiter's magnetosphere could produce sufficient organic and oxidant molecules for an Europan biosphere (Chyba, 2000). We restrict our attention to microbial mats that could still be thriving in spite of the extreme conditions of radiation on Europa. We are especially concerned with sulfur patches discovered by the Galileo mission. In the near future there are technologies available to settle the question of habitability on Europa, such as penetrators that are currently being developed for preliminary trials nearer to the Earth—the Moon-Lite mission (Smith et al., 2008). If analogies

  14. Separation and Detection of Toxic Gases with a Silicon Micromachined Gas Chromatography System

    Science.gov (United States)

    Kolesar, Edward S.; Reston, Rocky R.

    1995-01-01

    A miniature gas chromatography (GC) system was designed and fabricated using silicon micromachining and integrated circuit (IC) processing techniques. The silicon micromachined gas chromatography system (SMGCS) is composed of a miniature sample injector that incorporates a 10 microliter sample loop; a 0.9 meter long, rectangular shaped (300 micrometer width and 10 micrometer height) capillary column coated with a 0.2 micrometer thick copper phthalocyanine (CuPc) stationary phase; and a dual detector scheme based upon a CuPc-coated chemiresistor and a commercially available 125 micrometer diameter thermal conductivity detector (TCD) bead. Silicon micromachining was employed to fabricate the interface between the sample injector and the GC column, the column itself, and the dual detector cavity. A novel IC thin-film processing technique was developed to sublime the CuPc stationary phase coating on the column walls that were micromachined in the host silicon wafer substrate and Pyrex (r) cover plate, which were then electrostatically bonded together. The SMGCS can separate binary gas mixtures composed of parts-per-million (ppm) concentrations of ammonia (NH3) and nitrogen dioxide (NO2) when isothermally operated (55-80 degrees C). With a helium carrier gas and nitrogen diluent, a 10 microliter sample volume containing ammonia and nitrogen dioxide injected at 40 psi ((2.8 x 10(exp 5)Pa)) can be separated in less than 30 minutes.

  15. Continuous determination of volatile products in anaerobic fermenters by on-line capillary gas chromatography

    International Nuclear Information System (INIS)

    Diamantis, V.; Melidis, P.; Aivasidis, A.

    2006-01-01

    Bio-ethanol and biogas produced during the anaerobic conversion of organic compounds has been a subject of great interest since the oil crisis of the 1970s. In ethanol fermentation and anaerobic treatment of wastewaters, end-product (ethanol) and intermediate-products (short-chain fatty acids, SCFA) cause inhibition that results in reduced process efficiency. Control of these constituents is of utmost importance for bioreactor optimization and process stability. Ethanol and SCFA can be detected with precision by capillary gas chromatography usually conducted in off-line measurements. In this work, an on-line monitoring and controlling system was developed and connected to the fermenter via an auto-sampling equipment, which could perform the feeding, filtration and dilution of the sample and final injection into the gas chromatograph through an automation-based programmed procedure. The sample was continuously pumped from the recycle stream of the bioreactor and treated using a microfiltration unit. The concentrate was returned to the reactor while the permeate was quantitatively mixed with an internal standard solution. The system comprised of a gas chromatograph with the flow cell and one-shot sampler and a PC with the appropriate software. The on-line measurement of ethanol and SCFA, directly from the liquid phase of an ethanol fermenter and a high-rate continuous mode anaerobic digester, was accomplished by gas chromatography. Also, this monitoring and controlling system was proved to be effective in the continuous fermentation of alcohol-free beer

  16. Simultaneous determination of lincomycin and spectinomycin residues in animal tissues by gas chromatography-nitrogen phosphorus detection and gas chromatography-mass spectrometry with accelerated solvent extraction.

    Science.gov (United States)

    Tao, Y; Chen, D; Yu, G; Yu, H; Pan, Y; Wang, Y; Huang, L; Yuan, Z

    2011-02-01

    A new multi-dimensional analytical method using gas chromatography-nitrogen phosphorus detection (GC-NPD) and gas chromatography-mass spectrometry (GC-MS) was developed for qualitative and quantitative measurement of lincomycin and spectinomycin residues in food animal tissues. This method is based on a new extraction procedure using accelerated solvent extraction (ASE). The analytes were extracted by phosphate buffer with trichloroacetic acid deproteinization and clean-up by C₁₈ solid-phase extraction (SPE) adding dodecanesulfonic acid sodium salt as an ion-pair reagent. The eluted fraction was evaporated and derivatised with N,O-bis(trimethylsilyl) trifluoroacetamide (BSTFA) for GC-NPD analysis and GC-MS confirmation. Parameters for extraction pressure, temperature and cycle of ASE, clean-up, derivatisation and analysis procedure were optimised. The method was validated in muscle, kidney and liver of swine, bovine with a low concentration (limit of quantification) of 16.4 and 21.4 µg kg⁻¹ for these two analytes using GC-NPD. For GC-MS, the limits of quantification were 4.1 and 5.6 µg kg⁻¹, respectively. Spiked recoveries from levels of 20 to 200 µg kg⁻¹ were found to be between 73% and 99% with a relative standard deviation (RSD) of less than 17% in GC-NPD. For GC-MS, levels from 5 to 20 µg kg⁻¹ had between 70% and 93% with an RSD of less than 21%. This rapid and reliable method can be used for the characterisation and quantification of residues of lincomycin and spectinomycin in animal tissues.

  17. A small electron beam ion trap/source facility for electron/neutral–ion collisional spectroscopy in astrophysical plasmas

    Science.gov (United States)

    Liang, Gui-Yun; Wei, Hui-Gang; Yuan, Da-Wei; Wang, Fei-Lu; Peng, Ji-Min; Zhong, Jia-Yong; Zhu, Xiao-Long; Schmidt, Mike; Zschornack, Günter; Ma, Xin-Wen; Zhao, Gang

    2018-01-01

    Spectra are fundamental observation data used for astronomical research, but understanding them strongly depends on theoretical models with many fundamental parameters from theoretical calculations. Different models give different insights for understanding a specific object. Hence, laboratory benchmarks for these theoretical models become necessary. An electron beam ion trap is an ideal facility for spectroscopic benchmarks due to its similar conditions of electron density and temperature compared to astrophysical plasmas in stellar coronae, supernova remnants and so on. In this paper, we will describe the performance of a small electron beam ion trap/source facility installed at National Astronomical Observatories, Chinese Academy of Sciences.We present some preliminary experimental results on X-ray emission, ion production, the ionization process of trapped ions as well as the effects of charge exchange on the ionization.

  18. An ion trap time-of-flight mass spectrometer with high mass resolution for cold trapped ion experiments

    Science.gov (United States)

    Schmid, P. C.; Greenberg, J.; Miller, M. I.; Loeffler, K.; Lewandowski, H. J.

    2017-12-01

    Trapping molecular ions that have been sympathetically cooled with laser-cooled atomic ions is a useful platform for exploring cold ion chemistry. We designed and characterized a new experimental apparatus for probing chemical reaction dynamics between molecular cations and neutral radicals at temperatures below 1 K. The ions are trapped in a linear quadrupole radio-frequency trap and sympathetically cooled by co-trapped, laser-cooled, atomic ions. The ion trap is coupled to a time-of-flight mass spectrometer to readily identify product ion species and to accurately determine trapped ion numbers. We discuss, and present in detail, the design of this ion trap time-of-flight mass spectrometer and the electronics required for driving the trap and mass spectrometer. Furthermore, we measure the performance of this system, which yields mass resolutions of m/Δm ≥ 1100 over a wide mass range, and discuss its relevance for future measurements in chemical reaction kinetics and dynamics.

  19. Integrated gas and liquid chromatography tandem mass spectrometry for forensic engine lubricating oil identification

    International Nuclear Information System (INIS)

    Shang, D.; McPherson, B.

    2009-01-01

    This paper presented a method for rapid chemical characterization of engine lubricating oils. Motor oils typically contain up to 5 per cent additives, such as detergent, antifoamant, dispersant, emulsifier, antioxidant, friction modifier, colour stabilizer and corrosion inhibitors. Different lube oil products usually have either different additives in various concentrations. As such, the formulation of additives in lube oil products should provide fingerprint information for forensic oil identification. The characterization method used in this study was based on a newly developed fast solvent liquid-liquid sample extraction procedure that combined the use of both liquid chromatography tandem mass spectrometry (LC-MS) and gas chromatography-mass spectrometry (GC-MS) simultaneously together with gas chromatography flame ionization detection (GC-FID). The method was used on a blind sample testing of commercially available engine lubricating products. The sample extraction procedure involved extraction of additives into acidified acetonitrile, two hexane washes of hydrophobic components of lube oil, filtration, and dilution with solvents for GC and LC analysis. The new method proved to be rapid and easy to use. It enabled the identification of unknown additives and hydrocarbons in many different types of fresh lube oils. Further tests will be needed to determine if this method can be used on real-world weathered samples. The method is part of an ongoing effort to deal with mysterious chemical spills, an important aspect of environmental protection and emergency preparedness. 8 refs., 7 figs

  20. Evaluation of a gas chromatography method for azelaic acid determination in selected biological samples.

    Science.gov (United States)

    Garelnabi, Mahdi; Litvinov, Dmitry; Parthasarathy, Sampath

    2010-09-01

    Azelaic acid (AzA) is the best known dicarboxilic acid to have pharmaceutical benefits and clinical applications and also to be associated with some diseases pathophysiology. We extracted and methylesterified AzA and determined its concentration in human plasma obtained from healthy individuals and also in mice fed AzA containing diet for three months. AzA was detected in Gas Chromatography (GC) and confirmed by Liquid chromatography mass spectrometry (LCMS), and gas chromatography mass spectrometry (GCMC). Our results have shown that AzA can be determined efficiently in selected biological samples by GC method with 1nM limit of detection (LoD) and the limit of quantification (LoQ); was established at 50nM. Analytical Sensitivity as assayed by hexane demonstrated an analytical sensitivity at 0.050nM. The method has demonstrated 8-10% CV batch repeatability across the sample types and 13-18.9% CV for the Within-Lab Precision analysis. The method has shown that AzA can efficiently be recovered from various sample preparation including liver tissue homogenate (95%) and human plasma (97%). Because of its simplicity and lower limit of quantification, the present method provides a useful tool for determining AzA in various biological sample preparations.

  1. Fuel spill identification by gas chromatography -- genetic algorithms/pattern recognition techniques

    International Nuclear Information System (INIS)

    Lavine, B.K.; Moores, A.J.; Faruque, A.

    1998-01-01

    Gas chromatography and pattern recognition methods were used to develop a potential method for typing jet fuels so a spill sample in the environment can be traced to its source. The test data consisted of 256 gas chromatograms of neat jet fuels. 31 fuels that have undergone weathering in a subsurface environment were correctly identified by type using discriminants developed from the gas chromatograms of the neat jet fuels. Coalescing poorly resolved peaks, which occurred during preprocessing, diminished the resolution and hence information content of the GC profiles. Nevertheless a genetic algorithm was able to extract enough information from these profiles to correctly classify the chromatograms of weathered fuels. This suggests that cheaper and simpler GC instruments ca be used to type jet fuels

  2. Cosorption effect in gas chromatography: flow fluctuations caused by adsorbing carrier gases.

    Science.gov (United States)

    Matuszak, Daniel; Gaddy, Glen D; Aranovich, Gregory L; Donohue, Marc D

    2005-01-21

    Adsorbing carrier gases have a number of advantages in analytical and preparative gas chromatography, such as clearer detector signals and higher column efficiencies. This work shows that adsorbing carrier gases also may be useful because they cause the mobile phase flow rate to become unsteady after injecting a small amount of sample. This work shows that a 100 microL sample of helium can liberate enough carbon dioxide carrier gas from a zeolite 5A packed column at 373 K, that the departure from the steady-state flow rate had an upper lobe area of 586 microL of carrier gas. This was confirmed by coupling a modified Langmuir kinetic model with the Ergun equation.

  3. Structural classification of acyl-substituted Quillaja saponins by electrospray ionisation ion trap multiple-stage mass spectrometry in combination with multivariate analysis.

    Science.gov (United States)

    Bankefors, Johan; Nord, Lars I; Kenne, Lennart

    2008-12-01

    Thirty-eight saponins in two chromatographic fractions (QH-B and QH-C) from Quillaja saponaria Molina have been separated by a two-step high-performance liquid chromatography (HPLC) procedure and investigated by electrospray ionisation ion trap multiple-stage mass spectrometry (ESI-ITMS(n)) in positive ion mode. MS(2) and MS(3) spectra of the compounds were investigated by principal component analysis (PCA) and could be classified by partial least squares - discriminant analysis (PLS-DA) according to the structures of the oligosaccharides at C-3 and C-28 of the saponins. Four minor components with novel structures were found in a previously non-investigated fraction of QH-C. The structures of two of these components, J1 and J1a, were predicted by PLS-DA whereas the structures of the two others, J2 and J3, were only partly predicted. The structures of J1 and J1a were composed of structural elements found in the 34 known saponins whereas a new acyl substituent, not included in the training set used for calibration of the PLS-DA models, was found in J2 and J3, making these two components outliers. The complete structures of the four components were confirmed by monosaccharide analysis, MS(n) data and (1)H NMR spectroscopy.

  4. High-pressure liquid chromatography with direct injection of gas sample.

    Science.gov (United States)

    Astanin, Anton I; Baram, Grigory I

    2017-06-09

    The conventional method of using liquid chromatography to determine the composition of a gaseous mixture entails dissolving vapors in a suitable solvent, then obtaining a chromatograph of the resulting solution. We studied the direct introduction of a gaseous sample into a C18 reversed-phase column, followed by separation of the components by HPLC with UV detection. Since the chromatography was performed at high pressure, vapors readily dissolved in the eluent and the substances separated in the column as effectively as in liquid samples. Samples were injected into the column in two ways: a) through the valve without a flow stop; b) after stopping the flow and relieving all pressure. We showed that an injectable gas volume could reach 70% of column dead volume. When an injected gaseous sample volume was less than 10% of the column dead volume, the resulting peaks were symmetrical and the column efficiency was high. Copyright © 2017 Elsevier B.V. All rights reserved.

  5. Gas chromatography/mass spectrometry and pyrolysis-gas chromatography/mass spectrometry for the chemical characterisation of modern and archaeological figs (Ficus carica).

    Science.gov (United States)

    Ribechini, Erika; Pérez-Arantegui, Josefina; Colombini, Maria Perla

    2011-06-24

    Gas chromatography/mass spectrometry (GC/MS) after alkaline hydrolysis, solvent extraction and trimethylsilylation, and analytical pyrolysis using hexamethyldisilazane (HMDS) for in situ derivatisation followed by gas chromatographic/mass spectrometric analysis (Pyrolysis-silylation-GC/MS) were used to investigate the hydrolysable and soluble constituents, and the polymerised macromolecules of an archaeological fig (Ficus carica) recovered in Zaragoza (Spain), as well as of modern figs. The main aim was to study the compositional alterations undergone by the fig tissues in a particular archaeological environment: the fig was in a vessel and covered by a layer of a mixture of orpiment and gypsum. A comparison between the GC/MS results from modern and archaeological figs revealed that degradative reactions took place, leading to the disappearance/depletion of reactive (unsaturated fatty acids) and sensitive compounds (phytosterols and triterpenes). Py-silylation-GC/MS data provided evidence of a significant degradation of the saccharide and lipid components of the fig tissue, which left a residue enriched in polyphenols and polyesters. Copyright © 2011 Elsevier B.V. All rights reserved.

  6. Amperometric detector for gas chromatography based on a silica sol-gel solid electrolyte.

    Science.gov (United States)

    Steinecker, William H; Miecznikowski, Krzysztof; Kulesza, Pawel J; Sandlin, Zechariah D; Cox, James A

    2017-11-01

    An electrochemical cell comprising a silica sol-gel solid electrolyte, a working electrode that protrudes into a gas phase, and reference and counter electrodes that contact the solid electrolyte comprises an amperometric detector for gas chromatography. Under potentiostatic conditions, a current related to the concentration of an analyte in the gas phase is produced by its oxidation at the three-phase boundary among the sol-gel, working electrode, and the gas phase. The sol-gel is processed to contain an electrolyte that also serves as a humidistat to maintain a constant water activity even in the presence the gas chromatographic mobile phase. Response was demonstrated toward a diverse set of analytes, namely hydrogen, 1,2-ethandithiol, phenol, p-cresol, and thioanisole. Using flow injection amperometry of hydrogen with He as the carrier gas, 90% of the steady-state current was achieved in < 1s at a flow rate of 20mLmin -1 . A separation of 1,2-ethandithiol, phenol, p-cresol, and thioanisole at a 2.2mLmin -1 flow rate was achieved with respective detection limits (k = 3 criterion) of 4, 1, 3, and 70 ppmv when the working electrode potential was 800mV. Copyright © 2017 Elsevier B.V. All rights reserved.

  7. Investigation of ion capture in an electron beam ion trap charge-breeder for rare isotopes

    Science.gov (United States)

    Kittimanapun, Kritsada

    Charge breeding of rare isotope ions has become an important ingredient for providing reaccelerated rare isotope beams for science. At the National Superconducting Cyclotron Laboratory (NSCL), a reaccelerator, ReA, has been built that employs an advanced Electron Beam Ion Trap (EBIT) as a charge breeder. ReA will provide rare-isotope beams with energies of a few hundred keV/u up to tens of MeV/u to enable the study of properties of rare isotopes via low energy Coulomb excitation and transfer reactions, and to investigate nuclear reactions important for nuclear astrophysics. ReA consists of an EBIT charge breeder, a charge-over-mass selector, a room temperature radio-frequency quadrupole accelerator, and a superconducting radio-frequency linear accelerator. The EBIT charge breeder features a high-current electron gun, a long trap structure, and a hybrid superconducting magnet to reach both high acceptance for injected low-charge ions as well as high-electron beam current densities for fast charge breeding. In this work, continuous ion injection and capture in the EBIT have been investigated with a dedicated Monte-Carlo simulation code and in experimental studies. The Monte-Carlo code NEBIT considers the electron-impact ionization cross sections, space charge due to the electron beam current, ion dynamics, electric field from electrodes, and magnetic field from the superconducting magnet. Experiments were performed to study the capture efficiency as a function of injected ion beam current, electron beam current, trap size, and trap potential depth. The charge state evolution of trapped ions was studied, providing information about the effective current density of the electron beam inside the EBIT. An attempt was made to measure the effective space-charge potential of the electron beam by studying the dynamics of a beam injected and reflected inside the trap.

  8. EBIT (Electron Beam Ion Trap), N-Division Experimental Physics. Annual report, 1994

    Energy Technology Data Exchange (ETDEWEB)

    Schneider, D. [ed.

    1995-10-01

    The experimental groups in the Electron Beam Ion Trap (EBIT) program continue to perform front-line research with trapped and extracted highly charged ions (HCI) in the areas of ion/surface interactions, atomic spectroscopy, electron-ion interaction and structure measurements, highly charged ion confinement, and EBIT development studies. The ion surface/interaction studies which were initiated five years ago have reached a stage where they an carry out routine investigations, as well as produce breakthrough results towards the development of novel nanotechnology. At EBIT and SuperEBIT studies of the x-ray emission from trapped ions continue to produce significant atomic structure data with high precision for few electron systems of high-Z ions. Furthermore, diagnostics development for magnetic and laser fusion, supporting research for the x-ray laser and weapons programs, and laboratory astrophysics experiments in support of NASA`s astrophysics program are a continuing effort. The two-electron contributions to the binding energy of helium like ions were measured for the first time. The results are significant because their precision is an order of magnitude better than those of competing measurements at accelerators, and the novel technique isolates the energy corrections that are the most interesting. The RETRAP project which was initiated three years ago has reached a stage where trapping, confining and electronic cooling of HCI ions up to Th{sup 80+} can be performed routinely. Measurements of the rates and cross sections for electron transfer from H{sub 2} performed to determine the lifetime of HCI up to Xe{sup q+} and Th{sup q+} (35 {le} q {le} 80) have been studied at mean energies estimated to be {approximately} 5 q eV. This combination of heavy ions with very high charges and very low energies is rare in nature, but may be encountered in planned fusion energy demonstration devices, in highly charged ion sources, or in certain astrophysical events.

  9. EBIT (Electron Beam Ion Trap), N-Division Experimental Physics. Annual report, 1994

    International Nuclear Information System (INIS)

    Schneider, D.

    1995-10-01

    The experimental groups in the Electron Beam Ion Trap (EBIT) program continue to perform front-line research with trapped and extracted highly charged ions (HCI) in the areas of ion/surface interactions, atomic spectroscopy, electron-ion interaction and structure measurements, highly charged ion confinement, and EBIT development studies. The ion surface/interaction studies which were initiated five years ago have reached a stage where they an carry out routine investigations, as well as produce breakthrough results towards the development of novel nanotechnology. At EBIT and SuperEBIT studies of the x-ray emission from trapped ions continue to produce significant atomic structure data with high precision for few electron systems of high-Z ions. Furthermore, diagnostics development for magnetic and laser fusion, supporting research for the x-ray laser and weapons programs, and laboratory astrophysics experiments in support of NASA's astrophysics program are a continuing effort. The two-electron contributions to the binding energy of helium like ions were measured for the first time. The results are significant because their precision is an order of magnitude better than those of competing measurements at accelerators, and the novel technique isolates the energy corrections that are the most interesting. The RETRAP project which was initiated three years ago has reached a stage where trapping, confining and electronic cooling of HCI ions up to Th 80+ can be performed routinely. Measurements of the rates and cross sections for electron transfer from H 2 performed to determine the lifetime of HCI up to Xe q+ and Th q+ (35 ≤ q ≤ 80) have been studied at mean energies estimated to be ∼ 5 q eV. This combination of heavy ions with very high charges and very low energies is rare in nature, but may be encountered in planned fusion energy demonstration devices, in highly charged ion sources, or in certain astrophysical events

  10. Utility of Higher Harmonics in Electrospray Ionization Fourier Transform Electrostatic Linear Ion Trap Mass Spectrometry.

    Science.gov (United States)

    Dziekonski, Eric T; Johnson, Joshua T; McLuckey, Scott A

    2017-04-18

    Mass resolution (M/ΔM fwhm) is observed to linearly increase with harmonic order in a Fourier transform electrostatic linear ion trap (ELIT) mass spectrometer. This behavior was predicted by Grosshans and Marshall for frequency-multiple detection in a Fourier transform ion cyclotron resonance mass spectrometer only for situations when the prominent mechanism for signal decay is ion ejection from the trap. As the analyzer pressure in our ELIT chamber is relatively high, such that collisional scattering and collision-induced dissociation are expected to underlie much of the ion loss, we sought to explore the relationship between harmonic order and mass resolution. Mass resolutions of 36 900 (fundamental), 75 850 (2nd harmonic), and 108 200 (3rd harmonic) were obtained for GdO + (avg. m/z 173.919) with a transient length of 300 ms. To demonstrate that the mass resolution was truly increasing with harmonic order, the unresolved isotopes at the fundamental distribution of cytochrome c +8 (m/z ∼ 1549) were nearly baseline, resolved at the third harmonic (mass resolution ≈ 23 000) with a transient length of only 200 ms. This experiment demonstrates that, when the ion density is sufficiently low, ions with frequency differences of less than 4 Hz remain uncoalesced. Higher harmonics can be used to increase the effective mass resolution for a fixed transient length and thereby may enable the resolution of closely spaced masses, determination of a protein ion's charge state, and study of the onset of peak coalescence when the resolution at the fundamental frequency is insufficient.

  11. Performance of the Linear Ion Trap Mass Spectrometer for the Mars Organic Molecule Analyzer (MOMA) Investigation on the 2018 Exomars Rover

    Science.gov (United States)

    Arevalo, Ricardo, Jr.; Brinckerhoff, William B.; Pinnick, Veronica T.; van Amerom, Friso H. W.; Danell, Ryan M.; Li, Xiang; Getty, Stephanie; Hovmand, Lars; Atanassova, Martina; Mahaffy, Paul R.; hide

    2014-01-01

    The 2018 ExoMars rover mission includes the Mars Organic Molecule Analyzer (MOMA) investigation. MOMA will examine the chemical composition of samples acquired from depths of up to two meters below the martian surface, where organics may be protected from degradation derived from cosmic radiation and/or oxidative chemical reactions. When combined with the complement of instruments in the rover's Pasteur Payload, MOMA has the potential to reveal the presence of a wide range of organics preserved in a variety of mineralogical environments, and to begin to understand the structural character and potential origin of those compounds. The MOMA investigation is led by the Max Planck Institute for Solar System Research (MPS) with the mass spectrometer subsystem provided by NASA GSFC. MOMA's linear ion trap mass spectrometer (ITMS) is designed to analyze molecular composition of: (i) gas evolved from pyrolyzed powder samples and separated in a gas chromatograph; and, (ii) ions directly desorbed from crushed solid samples at Mars ambient pressure, as enabled by a pulsed UV laser system, fast-actuating aperture valve and capillary ion inlet. Breadboard ITMS and associated electronics have been advanced to high end-to-end fidelity in preparation for flight hardware delivery to Germany in 2015.

  12. Comparison of the quantification of caffeine in human plasma by gas chromatography and ELISA

    Directory of Open Access Journals (Sweden)

    A.B. Carregaro

    2001-06-01

    Full Text Available In the present study we evaluated the precision of the ELISA method to quantify caffeine in human plasma and compared the results with those obtained by gas chromatography. A total of 58 samples were analyzed by gas chromatography using a nitrogen-phosphorus detector and routine techniques. For the ELISA test, the samples were diluted to obtain a concentration corresponding to 50% of the absorbance of the standard curve. To determine whether the proximity between the I50 of the standard curve and that of the sample would bring about a more precise result, the samples were divided into three blocks according to the criterion of difference, in modulus, of the I50 of the standard curve and of the I50 of the sample. The samples were classified into three groups. The first was composed of 20 samples with I50 up to 1.5 ng/ml, the second consisted of 21 samples with I50 ranging from 1.51 to 3 ng/ml, and the third of 17 samples with I50 ranging from 3.01 to 13 ng/ml. The determination coefficient (R² = 0.999 showed that the data obtained by gas chromatography represented a reliable basis. The results obtained by ELISA were also reliable, with an estimated Pearson correlation coefficient of 0.82 between the two methods. This coefficient for the different groups (0.88, 0.79 and 0.49 for groups 1, 2 and 3, respectively showed greater reliability for the test with dilutions closer to I50.

  13. Multiple inert gas elimination technique by micropore membrane inlet mass spectrometry--a comparison with reference gas chromatography.

    Science.gov (United States)

    Kretzschmar, Moritz; Schilling, Thomas; Vogt, Andreas; Rothen, Hans Ulrich; Borges, João Batista; Hachenberg, Thomas; Larsson, Anders; Baumgardner, James E; Hedenstierna, Göran

    2013-10-15

    The mismatching of alveolar ventilation and perfusion (VA/Q) is the major determinant of impaired gas exchange. The gold standard for measuring VA/Q distributions is based on measurements of the elimination and retention of infused inert gases. Conventional multiple inert gas elimination technique (MIGET) uses gas chromatography (GC) to measure the inert gas partial pressures, which requires tonometry of blood samples with a gas that can then be injected into the chromatograph. The method is laborious and requires meticulous care. A new technique based on micropore membrane inlet mass spectrometry (MMIMS) facilitates the handling of blood and gas samples and provides nearly real-time analysis. In this study we compared MIGET by GC and MMIMS in 10 piglets: 1) 3 with healthy lungs; 2) 4 with oleic acid injury; and 3) 3 with isolated left lower lobe ventilation. The different protocols ensured a large range of normal and abnormal VA/Q distributions. Eight inert gases (SF6, krypton, ethane, cyclopropane, desflurane, enflurane, diethyl ether, and acetone) were infused; six of these gases were measured with MMIMS, and six were measured with GC. We found close agreement of retention and excretion of the gases and the constructed VA/Q distributions between GC and MMIMS, and predicted PaO2 from both methods compared well with measured PaO2. VA/Q by GC produced more widely dispersed modes than MMIMS, explained in part by differences in the algorithms used to calculate VA/Q distributions. In conclusion, MMIMS enables faster measurement of VA/Q, is less demanding than GC, and produces comparable results.

  14. Determination of polar pharmaceuticals in sewage water of Greece by gas chromatography-mass spectrometry.

    Science.gov (United States)

    Koutsouba, V; Heberer, Th; Fuhrmann, B; Schmidt-Baumler, K; Tsipi, D; Hiskia, A

    2003-04-01

    Sewage influents and effluents of different urban areas of Greece, were analyzed for polar pharmaceutical residues, used in human medicine. Drugs investigated were the anti-inflammatory drugs diclofenac and ibuprofen, the metabolite of the drugs clofibrates used as blood lipid regulators, clofibric acid and the analgesics phenazone and propyphenazone. Analysis was carried out using capillary gas chromatography-mass spectrometry with selected ion monitoring. The method used was involved solid phase extraction (C(18)) and derivatization with pentafluorobenzyl bromide. Diclofenac was detected in every sewage effluent sample.

  15. [Quantitative determination of strychnine in blood and urine by gas chromatography with mass-selective detector].

    Science.gov (United States)

    Kataev, S S; Krylova, E A

    2010-01-01

    A method for the quantitative determination of strychnine in biological fluids by gas chromatography--mass spectrometry is proposed. The preparation of samples for the analysis included extraction of strychnine from blood and urine with the use of AccuBond(II) EVIDEX cartridges for solid-phase extraction and SPEC MP3 disks respectively. The efficiency of extraction was estimated at 0.05 mg/l for blood and 0.02 mg/l for urine. The detection limit was 0.10 mg/l in blood and 0.05 mg/l in urine.

  16. Simultaneous determination of aliphatic hydrocarbons, PCBs and PCTs in pork liver by gas chromatography

    Energy Technology Data Exchange (ETDEWEB)

    Gonzalez-Barros, C. [Dept. de Quimica Analitica, Nutricion y Bromatologia, Area Nutricion y Bromatologia, Facultad de Farmacia, Santiago de Compostela (Spain); Alvarez Pineiro, M.E. [Inst. de Investigacion y Analisis Alimentarios, Lab. de Bromatologia, Facultad de Farmacia, Santiago de Compostela (Spain); Simal Lozano, J. [Dept. de Quimica Analitica, Nutricion y Bromatologia, Area Nutricion y Bromatologia, Facultad de Farmacia, Santiago de Compostela (Spain); Lage Yusty, M.A. [Inst. de Investigacion y Analisis Alimentarios, Lab. de Bromatologia, Facultad de Farmacia, Santiago de Compostela (Spain)

    1996-10-01

    A multicomponent extraction/concentration procedure has been developed for the enrichment of PCBs, PCTs and aliphatic hydrocarbons (pristane, C{sub 18}, C{sub 19}, C{sub 20}, C{sub 22}, C{sub 24}, C{sub 28}, C{sub 32} and C{sub 36}) in pork liver. These components of the enriched extract were then simultaneously determined by gas chromatography. Mean recoveries ranged from 81.5% for pristane to 93% for PCBs; CV % (0.9-6.7) indicated the method to be both precise and reproducible. (orig.)

  17. Comparative characteristic of concentration units relating to reference materials for gas chromatography analysis of hydrocarbon samples

    Directory of Open Access Journals (Sweden)

    S. A. Arystanbekova

    2014-01-01

    Full Text Available Application of a method of absolute calibration relating to gas chromatography analysis of liquid hydrocarbon samples is considered. It is shown for this task that both from theoretical, and practical points of view the optimum concentration unit is mass (not molar fraction. Information on average molar mass of the analyzed sample is necessary for the determination of analytes in liquid hydrocarbon samples in terms of mole fraction. Meanwhile, the normative documents of rather high rank (ASTM, ISO, GOST, GOST R concerning methods of the determination of average molar weight of samples of such a kind are absent.

  18. Determination of ketone bodies in blood by headspace gas chromatography-mass spectrometry

    DEFF Research Database (Denmark)

    Holm, Karen Marie Dollerup; Linnet, Kristian; Rasmussen, Brian Schou

    2010-01-01

    A gas chromatography-mass spectrometry (GC-MS) method for determination of ketone bodies (ß-hydroxybutyrate, acetone, and acetoacetate) in blood is presented. The method is based on enzymatic oxidation of D-ß-hydroxybutyrate to acetoacetate, followed by decarboxylation to acetone, which...... was quantified by the use of headspace GC-MS using acetone-(13)C(3) as an internal standard. The developed method was found to have intra- and total interday relative standard deviations acetone+acetoacetate levels (~25 to 8300 µM) and D-ß-hydroxybutyrate levels (~30 to 16500 µM). Recovery values varied...

  19. Validation of a method to determine methylmercury in fish tissues using gas chromatography

    International Nuclear Information System (INIS)

    Vega Bolannos, Luisa O.; Arias Verdes, Jose A.; Beltran Llerandi, Gilberto; Castro Diaz, Odalys; Moreno Tellez, Olga L.

    2000-01-01

    We validated a method to determine methylmercury in fish tissues using gas chromatography with an electron capture detector as described by the Association of Official Analytical Chemist (AOAC) International. The linear curve range was 0.02 to 1 g/ml and linear correlation coefficient was 0.9979. A 1 mg/kg methylmercury-contaminated fish sample was analyzed 20 times to determine repeatability of the method. The quantification limit was 0.16 mg/kg and detection limit was 0.06 ppm. Fish samples contaminated with 0.2 to 10 mg/kg methylmercury showed recovery indexes from 94.66 to 108.8%

  20. Gas chromatography/mass spectrometry characterization of historical varnishes of ancient Italian lutes and violin.

    Science.gov (United States)

    Echard, J P; Benoit, C; Peris-Vicente, J; Malecki, V; Gimeno-Adelantado, J V; Vaiedelich, S

    2007-02-12

    The organic constituents of historical vanishes from two ancient Italian lutes and a Stradivari violin, kept in the Musée de la musique in Paris, have been characterized using gas chromatography-mass spectrometry. Results have been compared with the chromatograms and mass spectra of recent as well as old naturally aged reference materials. The three historical varnishes analyzed have been shown to be oil varnishes, probably mixtures of linseed oil with resins. Identification of diterpenoids and triterpenoids compounds, and of the resins that may have been ingredients of the varnishes, are discussed in this paper.

  1. Gas chromatography analysisof organic compounds labelled with 14C and T

    International Nuclear Information System (INIS)

    Matukha, M.; Zhilka, L.; Khejze, K.-Kh.; Gehrner, Kh.

    1982-01-01

    Various methods of radio gas chromatography (RGC) including non-destructiveones are analyzed and compared as well as systems for their realization. The selected methods were verified in interlaboratory studies. The developed RGC-system produce a linear output signal proportional to the measured sample activity within 10 to 200 kBg. The system includes a nondestructive mass and radioactivity detector in series with combustion chamber of the effluent after TCD passage and 14 CO 2 absorber with ethanolamine. The activity of obtained solution is measured by means of liquid scintillation method [ru

  2. Chemical characterization using gas chromatography/mass spectrometry of two extracts from Phyllanthus orbicularis HBK

    International Nuclear Information System (INIS)

    Gutierrez Gaiten, Yamilet Irene; Miranda Martinez, Migdalia; Bello Alarcon, Adonis

    2011-01-01

    The objective of this paper was the chemical characterization of two extracts from Phyllanthus orbicularis HBK through gas chromatography/mass spectrometry. To this end, maceration with N-hexane and ethyl acetate was used to obtain the respective extracts. The study of the hexane extract identified 17 components in which hydrocarbonate structures prevailed, mainly cyclooctacosane. In the ethyl acetate extract, 19 compounds were detected, being the terpenoids the predominant, although the most abundant was sterol g-sitosterol. For the first time, the identified compounds are reported for this species

  3. Simple, specific analysis of organophosphorus and carbamate pesticides in sediments using column extraction and gas chromatography

    Science.gov (United States)

    Belisle, A.A.; Swineford, D.M.

    1988-01-01

    A simple, specific procedure was developed for the analysis of organophosphorus and carbamate pesticides in sediment. The wet soil was mixed with anhydrous sodium sulfate to bind water and the residues were column extracted in acetone:methylene chloride (1:l,v/v). Coextracted water was removed by additional sodium sulfate packed below the sample mixture. The eluate was concentrated and analyzed directly by capillary gas chromatography using phosphorus and nitrogen specific detectors. Recoveries averaged 93 % for sediments extracted shortly after spiking, but decreased significantly as the samples aged.

  4. Analysis of the anthraquinones aloe-emodin and aloin by gas chromatography/mass spectrometry.

    Science.gov (United States)

    ElSohly, Mahmoud A; Gul, Waseem; Murphy, Timothy P

    2004-12-20

    A procedure was developed for the determination of low levels of the anthraquinones aloe-emodin and aloin A (barbalin) in aloe products based on gas chromatography/mass spectrometry (GC/MS) of the trimethyl silyl (TMS) derivatives of these analytes in the presence of Chrysophanol used as internal standard. The method was used to analyze several aloe based commercial products (liquids, gels and solids). Wide variation in the level of these anthraquinones was observed among the different products. The method had a sensitivity of 0.005 ppm of aloe-emodin and 0.05 ppm of aloin.

  5. Headspace-gas chromatography: an ideal technique for sampling volatiles present in non-volatile matrices.

    Science.gov (United States)

    Ettre, L S

    2001-01-01

    After a brief overview of the techniques of static and dynamic headspace sampling and examples are given for the dynamic method ("purge and trap"). With respect to static headspace-gas chromatography (HS-GC) the theoretical background of the technique and the principles of the existing instruments are outlined. Five questions related to static HS-GC are discussed in more detail: trace analysis; ultratrace analysis with cryogenic enhancement of the analytes and elimination of the possible effect of excess water vapor in the sample; sample modification by carrying out reactions in the sample vial; non-equilibrium static HS-GC; and pattern analysis by HS-GC.

  6. Determination of cocaine in brazilian paper currency by capillary gas chromatography/mass spectrometry

    Directory of Open Access Journals (Sweden)

    Enrico Di Donato

    2007-01-01

    Full Text Available The presence of illicit drugs such as cocaine and marijuana in US paper currency is very well demonstrated. However, there is no published study describing the presence of cocaine and/or other illicit drugs in Brazilian paper currency. In this study, Brazilian banknotes were collected from nine cities, extracted and analyzed by capillary gas chromatography/mass spectrometry, in order to investigate the presence of cocaine. Bills were extracted with deionized water followed by ethyl acetate. Results showed that 93% of the bills presented cocaine in a concentration range of 2.38-275.10 µg/bill.

  7. Rapid quantitative detection of glucose content in glucose injection by reaction headspace gas chromatography.

    Science.gov (United States)

    Xie, Wei-Qi; Gong, Yi-Xian; Yu, Kong-Xian

    2017-10-20

    This work investigates an automated technique for rapid detecting the glucose content in glucose injection by reaction headspace gas chromatography (HS-GC). This method is based on the oxidation reaction of glucose in glucose injection with potassium dichromate. The carbon dioxide (CO 2 ) formed from the oxidation reaction can be quantitatively detected by GC. The results show that the relative standard deviation (RSD) of the present method was within 2.91%, and the measured glucose contents in glucose injection closely match those quantified by the reference method (relative differences glucose content in glucose injection related applications. Copyright © 2017 Elsevier B.V. All rights reserved.

  8. Validation of the determination of fatty acids in milk by gas chromatography

    OpenAIRE

    Simionato, Julliana Isabelle; Garcia, Juliana Carla; Santos, Geraldo Tadeu dos; Oliveira, Cláudio Celestino; Visentainer, Jesui Vergilio; Souza, Nilson Evelázio de

    2010-01-01

    Fatty acid methyl esters (FAMEs) in commercial milk samples were analyzed by gas chromatography coupled with flame ionization detection. The saturated fatty acids (SFA) were the most abundant. The major SFA were palmitic acid (16:0), estearic acid (18:0), and myristic acid (14:0). Significant differences (P < 0.500) were found between the amounts of palmitic acid (276 ± 17 mg g-1 and 248 ± 20 mg g-1) and myristic acid (95 ± 5 mg g-1 and 85 ± 7 mg g-1) in samples. However, no difference was ob...

  9. An efficient hydrophilic interaction liquid chromatography separation of 7 phospholipid classes based on a diol column

    NARCIS (Netherlands)

    Zhu, C.; Dane, A.; Spijksma, G.; Wang, M.; Greef, J. van der; Luo, G.; Hankemeier, T.; Vreeken, R.J.

    2012-01-01

    A hydrophilic interaction liquid chromatography (HILIC) - ion trap mass spectrometry method was developed for separation of a wide range of phospholipids. A diol column which is often used with normal phase chromatography was adapted to separate different phospholipid classes in HILIC mode using a

  10. Separation of polychlorinated dibenzo-p-dioxins/furans, non-ortho/mono/di/tri/tetra-ortho-polychlorinated biphenyls, and polybrominated diphenyl ethers groups of compounds prior to their determination with large volume injection gas chromatography-Quadrupole ion storage tandem mass spectrometry.

    Science.gov (United States)

    Roszko, Marek; Szymczyk, Krystyna; Jędrzejczak, Renata

    2013-10-17

    Polychlorinated dibenzo-p-dioxins/furans (PCDD/Fs), polychlorinated biphenyls (PCBs) and polybrominated diphenyl ethers (PBDEs) are important environmental contaminants. Their maximum legally allowable levels in food and environment are in the low pg g(-1) range. Therefore some highly selective and sensitive analytical methods must be used to determine them. Prior to final determination by GC/MS the cleaned-up samples have to be split into some fractions in view of large differences in concentrations of various analytes and existence of numerous chromatographic co-elutions (which in any case cannot be fully avoided). The aim of this study was to: (i) develop a robust, time-saving analytical method to isolate, clean-up and fractionate PCBs, PBDEs and PCDD/Fs prior to their determination with gas chromatography/ion trap mass spectrometry; (ii) assess method performance using laboratory validation data and some certified reference materials; (iii) use the developed method to assess PCB/PBDE/PCDD/F levels in samples of commercially available food. A combination of alumina, florisil, modified silica gel and two carbon columns were used for sample cleanup and fractionation. Separate fractions containing dioxins/furans, PBDE, non-ortho, mono-ortho and di-/tri-/tetra-ortho PCBs were obtained. The method statistical parameters were compatible with 1883/2006 EC Regulation (80-120%, RSD below 15%). The method performance was successfully used to evaluation of some real life food samples. Copyright © 2013 Elsevier B.V. All rights reserved.

  11. Mass Spectral Studies of 1-(2-Chloroethoxy)-2-[(2-chloroethyl)thio] Ethane and Related Compounds Using Gas ChromatographyMass Spectrometry and Gas ChromatographyTriple-Quadrupole Mass Spectrometry

    Science.gov (United States)

    2016-02-01

    characteristic ions. 15. SUBJECT TERMS Sulfur mustard Degradation product Tandem mass spectrometry (MS-MS) Fragmentation Gas chromatography (GC...MacIver, B.K.; Rohrbaugh, D.K.; Yang, Y.C. Thermal Degradation of Bis (2-Chloroethyl) Sulfide ( Mustard Gas ). Phosphorus Sulfur Silicon Relat. Elem...MASS SPECTRAL STUDIES OF 1-(2-CHLOROETHOXY)-2-[(2-CHLOROETHYL)THIO] ETHANE AND RELATED COMPOUNDS USING GAS

  12. Notification determining technical standards concerning prevention of radiation injuries by electron capture detectors for gas chromatography

    International Nuclear Information System (INIS)

    1981-01-01

    This rule is established under the provisions of the law on the prevention of radiation injuries by radioisotopes, the ordinance and the regulation for the execution of the law. This rule is applied to electron capture detectors for gas chromatography under the law. Basic terms are defined, such as detector radiation source, detector container and carrier gas. The detectors shall consist of detector radiation sources and containers, and the containers must be such that the radiation sources can not be easily taken away and never cause the danger to fall off. The induction and discharge mouths of the detector containers shall be shut tightly with caps, etc. The main structures and radiation sources of detectors shall be made of materials, which are difficult to corrode, and do not melt and easily cause chemical change below 800 deg. C. Detector radiation sources shall be made of metals plated with nickel 63 less than 20 milli-curie. The radiation dose rate on the surface of a detector shall be shielded to less than 0.06 milli-rem an hour. The temperature of detectors and carrier gas shall not exceed 350 deg. C. Corrosive gas shall not be used as carrier gas. The period of effective indication is 5 years. The method of washing, and the conditions of leak, heat-resistance and shock-resistance examinations are defined, respectively. (Okada, K.)

  13. [Rapid determination of pesticide multiresidues in porphyra by dispersive solid-phase extraction coupled with online gel permeation chromatography-gas chromatography-mass spectrometry].

    Science.gov (United States)

    Sun, Xiaojie; Guo, Mengmeng; Wang, Suyue; Tan, Zhijun; Li, Zhaoxin; Zhai, Yuxiu

    2014-10-01

    A rapid method for the simultaneous identification and quantification of pesticide multiresidues in porphyra was developed using gel permeation chromatography (GPC) coupled to gas chromatography-mass spectrometry (GPC-GC/MS). Nineteen pesticides (organochlorines, organophosphoruses, triazines and pyrethroids) were selected as the target analytes. The pretreatment method was applied consisting of organic solvent extraction followed by dispersive solid-phase extraction with graphitized carbon black (GCB) and primary secondary amine (PSA) adsorbents. GPC was also employed online to remove the large molecules such as pigments and lipids. The quantitative analysis was carried out by external standard method using gas chromatography coupled with mass spectrometry in selective ion monitoring (SIM) mode. Moreover, a large volume of sample was allowed to be injected using the program of GPC programmed-temperature vaporizer of gas chromatography to improve the sensitivity of measurements. The results showed that the calibration curves were linear (r > 0.995) in the range of 10-1,000 μg/L for all the pesticides. The limits of detection (LODs) for the pesticides in porphyra were from 0.005 to 0.03 mg/kg, and the average recoveries were between 70% and 120%. The advantages of the method are simple, sensitive and shorter operation time for analysis of pesticide residues in porphyra samples.

  14. Dosage direct des alcools dans les carburols par chromatographie en phase gazeuse Direct Gas Chromatographie Determination of Alcohols in Gasolines Blended by Oxygenated Compounds

    Directory of Open Access Journals (Sweden)

    Petroff N.

    2006-11-01

    Full Text Available Dans cette étude, on décrit une méthode de chromatographie en phase gazeuse utilisant une colonne remplie ; elle permet de doser, sans préfractionnement, les alcools jusqu'aux butanols dans les carburols (carburants additionnés de composés oxygénés. La phase stationnaire sélectionnée est le glycérol. This report describes a gas chromatographie method using a packed column. It allows the direct determination of alcohols up to butanols in gasolines blended with oxygenated compounds without prefractionation. Glycerol has been selected as stationary phase.

  15. Methods of analysis-Determination of pesticides in sediment using gas chromatography/mass spectrometry

    Science.gov (United States)

    Hladik, Michelle; McWayne, Megan M.

    2012-01-01

    A method for the determination of 119 pesticides in environmental sediment samples is described. The method was developed by the U.S. Geological Survey (USGS) in support of the National Water Quality Assessment (NAWQA) Program. The pesticides included in this method were chosen through prior prioritization. Herbicides, insecticides, and fungicides along with degradates are included in this method and span a variety of chemical classes including, but not limited to, chloroacetanilides, organochlorines, organophosphates, pyrethroids, triazines, and triazoles. Sediment samples are extracted by using an accelerated solvent extraction system (ASE®, and the compounds of interest are separated from co-extracted matrix interferences (including sulfur) by passing the extracts through high performance liquid chromatography (HPLC) with gel-permeation chromatography (GPC) along with the use of either stacked graphitized carbon and alumina solid-phase extraction (SPE) cartridges or packed Florisil®. Chromatographic separation, detection, and quantification of the pesticides from the sediment-sample extracts are done by using gas chromatography with mass spectrometry (GC/MS). Recoveries in test sediment samples fortified at 10 micrograms per kilogram (μg/kg) dry weight ranged from 75 to 102 percent; relative standard deviations ranged from 3 to 13 percent. Method detection limits (MDLs), calculated by using U.S. Environmental Protection Agency procedures (40 CFR 136, Appendix B), ranged from 0.6 to 3.4 μg/kg dry weight.

  16. A sensitive gas chromatography detector based on atmospheric pressure chemical ionization by a dielectric barrier discharge.

    Science.gov (United States)

    Kirk, Ansgar T; Last, Torben; Zimmermann, Stefan

    2017-02-03

    In this work, we present a novel concept for a gas chromatography detector utilizing an atmospheric pressure chemical ionization which is initialized by a dielectric barrier discharge. In general, such a detector can be simple and low-cost, while achieving extremely good limits of detection. However, it is non-selective apart from the use of chemical dopants. Here, a demonstrator manufactured entirely from fused silica capillaries and printed circuit boards is shown. It has a size of 75×60×25mm 3 and utilizes only 2W of power in total. Unlike other known discharge detectors, which require high-purity helium, this detector can theoretically be operated using any gas able to form stable ion species. Here, purified air is used. With this setup, limits of detection in the low parts-per-billion range have been obtained for acetone. Copyright © 2017 Elsevier B.V. All rights reserved.

  17. Quantitative characterization of urban sources of organic aerosol by high-resolution gas chromatography

    International Nuclear Information System (INIS)

    Hildemann, L.M.; Mazurek, M.A.; Cass, G.R.; Simoneit, B.R.T.

    1991-01-01

    Fine aerosol emissions have been collected from a variety of urban combustion sources, including an industrial boiler, a fireplace, automobiles, diesel trucks, gas-fired home appliances, and meat cooking operations, by use of a dilution sampling system. Other sampling techniques have been utilized to collect fine aerosol samples of paved road dust, brake wear, tire wear, cigarette smoke, tar pot emissions, and vegetative detritus. The organic matter contained in each of these samples has been analyzed via high-resolution gas chromatography. By use of a simple computational approach, a quantitative, 50-parameter characterization of the elutable fine organic aerosol emitted from each source type has been determined. The organic mass distribution fingerprints obtained by this approach are shown to differ significantly from each other for most of the source types tested, using hierarchical cluster analysis

  18. Heterogeneous catalysis on solids of gases diffusing through a liquid layer, studied by inverse gas chromatography.

    Science.gov (United States)

    Kapolos, John; Katsanos, Nicholas A

    2002-11-15

    Physicochemical parameters for heterogeneous catalytic reactions when the catalytic bed was under a liquid phase have been determined, using a non-linear adsorption isotherm by the reversed-flow version of inverse gas chromatography (RF-GC). The mathematical analysis developed in heterogeneous catalysis, mass transfer across gas-liquid boundaries, and diffusion coefficients of gases in liquids was associated with a non-linear adsorption isotherm to find the relevant equations pertaining to the problem. These equations were then used to calculate the adsorption/desorption rate constant, the rate constant for the first-order catalytic reaction and the equilibrium constant for the non-linear adsorption isotherm. The diffusion coefficients of the reactant in the liquid and gaseous phases and the partition coefficients for the distribution of the reactant between the gaseous and liquid phase were also determined.

  19. Separation of cis- and trans-Asarone from Acorus tatarinowii by Preparative Gas Chromatography

    Directory of Open Access Journals (Sweden)

    H. L. Zuo

    2012-01-01

    Full Text Available A preparative gas chromatography (pGC method was developed for the separation of isomers (cis- and trans-asarone from essential oil of Acorus tatarinowii. The oil was primarily fractionated by silica gel chromatography using different ratios of petroleum ether and ethyl acetate as gradient elution solvents. And then the fraction that contains mixture of the isomers was further separated by pGC. The compounds were separated on a stainless steel column packed with 10% OV-101 (3 m × 6 mm, i.d., and then the effluent was split into two gas flows. One percent of the effluent passed to the flame ionization detector (FID for detection and the remaining 99% was directed to the fraction collector. Two isomers were collected after 90 single injections (5 uL with the yield of 178 mg and 82 mg, respectively. Furthermore, the structures of the obtained compounds were identified as cis- and trans-asarone by 1H- and 13C-NMR spectra, respectively.

  20. Preparation and characterization of alkyl methacrylate-based monolithic columns for capillary gas chromatography applications.

    Science.gov (United States)

    Yusuf, Kareem; Aqel, Ahmad; A L Othman, Zeid; Badjah-Hadj-Ahmed, Ahmed Yacine

    2013-08-02

    Gas chromatography (GC) is considered the least common application of both polymer and silica-based monolithic columns. This study describes the fabrication of alkyl methacrylate monolithic materials for use as stationary phases in capillary gas chromatography. Following the deactivation of the capillary surface with 3-(trimethoxysilyl)propyl methacrylate (TMSM), the monoliths were formed by the co-polymerization of either hexyl methacrylate (HMA) or lauryl methacrylate (LMA) with different percentage of ethylene glycol dimethacrylate (EDMA) in presence of an initiator (azobisisobutyronitrile, AIBN) and a mixture of porogens include 1-propanol, 1,4-butanediol and water. The monoliths were prepared in 500mm length capillaries possessing inner diameters of 250μm. The efficiencies of the monolithic columns for low molecular weight compounds significantly improved as the percentage of crosslinker was increased, because of the greater proportion of pores less than 50nm. The columns containing lower percentages of crosslinker were able to rapidly separate a series of 8 alkane members in 0.7min, but the separation was less efficient for the light alkanes. Columns prepared with the lauryl methacrylate monomer yielded a different morphology for the monolith-interconnected channels. The channels were more branched, which increased the separation time, and unlike the other columns, allowed for temperature programming. Copyright © 2013 Elsevier B.V. All rights reserved.

  1. Development of a technique for mercury speciation and quantification using gas chromatography/mass spectrometry

    Energy Technology Data Exchange (ETDEWEB)

    Barshick, S.A.; Barshick, C.M.; Britt, P.F.; Vance, M.A.; Duckworth, D.C.

    1997-07-01

    One element of concern to DOE is mercury. Mercury was used extensively at the DOE facilities in Oak Ridge, Tennessee from 1950 to 1963 in the process of making lithium deuteride, a component of nuclear weapons. Although both the inorganic and organometallic forms of mercury are toxic to humans, the organic compounds are often more toxic. Since the toxicity of mercury is a function of its chemical form, an understanding of the interactions between commercially discharged mercury, naturally occurring mercury, and the environment in which they are present is vital. In this report, the authors have been investigating gas chromatography/mass spectrometry (GC/MS) for the analysis of both the organometallic and inorganic forms of mercury in the same environmental sample (e.g., solutions, soils, and sludges). Although gas chromatography is the classical technique for analyzing organic molecules, (e.g., organometallic compounds) little has been done on the analysis of inorganic compounds. In a previous publication, the authors described how a solid phase microextraction (SPME) fiber could be used to sample organomercurials from aqueous samples. An alkylation reaction was then carried out to transform chemically mercury nitrate into dimethylmercury; subsequent GC/MS analysis of this compound permitted quantification of the inorganic constituent. Subsequently, several different alkylation reagents have been synthesized that methylate any inorganic mercury compound to methylmercury iodide. Here, the authors report results on alkylation reaction time and the effect of pH on the population of the product.

  2. Oxysterols in cosmetics-Determination by planar solid phase extraction and gas chromatography-mass spectrometry.

    Science.gov (United States)

    Schrack, S; Hohl, C; Schwack, W

    2016-11-18

    Sterol oxidation products (SOPs) are linked to several toxicological effects. Therefore, investigation of potential dietary uptake sources particularly food of animal origin has been a key issue for these compounds. For the simultaneous determination of oxysterols from cholesterol, phytosterols, dihydrolanosterol and lanosterol in complex cosmetic matrices, planar solid phase extraction (pSPE) was applied as clean-up tool. SOPs were first separated from more non-polar and polar matrix constituents by normal phase thin-layer chromatography and then focussed into one target zone. Zone extraction was performed with the TLC-MS interface, followed by gas chromatography-mass spectrometry analysis. pSPE showed to be effective for cleaning up cosmetic samples as sample extracts were free of interferences, and gas chromatographic columns did not show any signs of overloading. Recoveries were between 86 and 113% with relative standard deviations of below 10% (n=6). Results of our market survey in 2016 showed that some cosmetics with ingredients of plant origin contained phytosterol oxidation products (POPs) in the low ppm range and therefore in line with levels reported for food. In lanolin containing products, total SOPs levels (cholesterol oxidation products (COPs), lanosterol oxidation products (LOPs), dihydrolanosterol oxidation products (DOPs)) being in the low percent range exceeded reported levels for food by several orders of magnitudes. Copyright © 2016 Elsevier B.V. All rights reserved.

  3. Identification and deconvolution of carbohydrates with gas chromatography-vacuum ultraviolet spectroscopy.

    Science.gov (United States)

    Schenk, Jamie; Nagy, Gabe; Pohl, Nicola L B; Leghissa, Allegra; Smuts, Jonathan; Schug, Kevin A

    2017-09-01

    Methodology for qualitative and quantitative determination of carbohydrates with gas chromatography coupled to vacuum ultraviolet detection (GC-VUV) is presented. Saccharides have been intently studied and are commonly analyzed by gas chromatography-mass spectrometry (GC-MS), but not always effectively. This can be attributed to their high degree of structural complexity: α/β anomers from their axial/equatorial hydroxyl group positioning at the C1-OH and flexible ring structures that lead to the open chain, five-membered ring furanose, and six-membered ring pyranose configurations. This complexity can result in convoluted chromatograms, ambiguous fragmentation patterns and, ultimately, analyte misidentification. In this study, mono-, di, and tri-saccharides were derivatized by two different methods-permethylation and oximation/pertrimethylsilylation-and analyzed by GC-VUV. These two derivatization methods were then compared for their efficiency, ease of use, and robustness. Permethylation proved to be a useful technique for the analysis of ketopentoses and pharmaceuticals soluble in dimethyl sulfoxide (DMSO), while the oximation/pertrimethylsilylation method prevailed as the more promising, overall, derivatization method. VUV spectra have been shown to be distinct and allow for efficient differentiation of isomeric species such as ketopentoses and reducing versus non-reducing sugars. In addition to identification, pharmaceutical samples containing several compounds were derivatized and analyzed for their sugar content with the GC-VUV technique to provide data for qualitative analysis. Copyright © 2017 Elsevier B.V. All rights reserved.

  4. Resolution of isomeric new designer stimulants using gas chromatography - Vacuum ultraviolet spectroscopy and theoretical computations.

    Science.gov (United States)

    Skultety, Ludovit; Frycak, Petr; Qiu, Changling; Smuts, Jonathan; Shear-Laude, Lindsey; Lemr, Karel; Mao, James X; Kroll, Peter; Schug, Kevin A; Szewczak, Angelica; Vaught, Cory; Lurie, Ira; Havlicek, Vladimir

    2017-06-08

    Distinguishing isomeric representatives of "bath salts", "plant food", "spice", or "legal high" remains a challenge for analytical chemistry. In this work, we used vacuum ultraviolet spectroscopy combined with gas chromatography to address this issue on a set of forty-three designer drugs. All compounds, including many isomers, returned differentiable vacuum ultraviolet/ultraviolet spectra. The pair of 3- and 4-fluoromethcathinones (m/z 181.0903), as well as the methoxetamine/meperidine/ethylphenidate (m/z 247.1572) triad, provided very distinctive vacuum ultraviolet spectral features. On the contrary, spectra of 4-methylethcathinone, 4-ethylmethcathinone, 3,4-dimethylmethcathinone triad (m/z 191.1310) displayed much higher similarities. Their resolution was possible only if pure standards were probed. A similar situation occurred with the ethylone and butylone pair (m/z 221.1052). On the other hand, majority of forty-three drugs was successfully separated by gas chromatography. The detection limits for all the drug standards were in the 2-4 ng range (on-column amount), which is sufficient for determinations of seized drugs during forensics analysis. Further, state-of-the-art time-dependent density functional theory was evaluated for computation of theoretical absorption spectra in the 125-240 nm range as a complementary tool. Copyright © 2017 Elsevier B.V. All rights reserved.

  5. Differentiation of endogenous and exogenous steroids by gas chromatography-combustion-mass spectrometry isotope ratio

    International Nuclear Information System (INIS)

    Montes de Oca Porto, Rodny; Rosado Perez, Aristides; Correa Vidal, Margarita Teresa

    2007-01-01

    Urinary steroids profiles are used to control the misuse of endogenous steroids such as testosterone and dihydrotestosterone. The testosterone/epistestosterone ratio, measured by Gas Chromatography-Mass Spectrometry, is used to control testosterone administration. When T/E ratio is higher than 4, consumption of testosterone or its precursors is suspected. Recent researches have demonstrated the effectiveness of Carbon Isotope Ratio Mass Spectrometry to detect and confirm endogenous steroids administration. The ratio of the two stable carbon isotopes 1 3 C and 1 2 C allows the differentiation of natural and synthetic steroids because synthetic steroids have lower 1 3 C abundance. In fact, the carbon isotope ratios can be used to determine endogenous steroids administration even when testosterone/epistestosterone ratio is at its normal value. In the current work, some of the most important aspects related to differentiation of endogenous and exogenous steroids by means of Gas Chromatography-Combustion-Isotope Ratio Mass Spectrometry are discussed. Also, this article provides a review about the purification and sample preparation previous to the analysis, and diet effects on carbon isotope ratio of endogenous anabolics steroids is presented too

  6. Assessment of Pesticide Residues in Some Fruits Using Gas Chromatography Coupled with Micro Electron Capture Detector

    Directory of Open Access Journals (Sweden)

    M. I. Bhanger

    2011-12-01

    Full Text Available A very sensitive analytical method for the determination of 26 pesticides in some fruits based on solid phase extraction (SPE cleanup was developed using gas chromatography (GC coupled with micro electron capture detector (μECD. The identity of the pesticides was confirmed by gas chromatography mass spectroscopy (GC-MS using selected ion monitoring (SIM mode. Ethyl acetate was used as a solvent for the extraction of pesticide residues with assistance of sonication. For cleanup an octadecyl, C18 SPE column was used. A linear response of μECD was observed for all pesticides with good correlation coefficients (>0.9992. Proposed method was successfully applied for the determination of pesticide residues in the orange, apple, and grape fruits. Average recoveries achieved for all of the pesticides at fortification levels of 0.05, 1.0 and 2.0 μg g-1 in analyzed fruits were above 90% with relative standard deviations (RSD less than 6

  7. Silica, alumina and aluminosilicates as solid stationary phases in gas chromatography

    Directory of Open Access Journals (Sweden)

    S. Faramawy

    2016-09-01

    Full Text Available Silica, alumina and Aluminosilicates of different Si/Al ratios were prepared by conventional precipitation or co-precipitation methods and then subjected to thermal treatment at 800 °C. The parent and thermally treated materials were characterized by means of FTIR, SEM and thermal analysis (DTA and TGA in order to elucidate the main structural properties. Surface textural characteristics were investigated by means of nitrogen adsorption–desorption isotherms at −196 °C. Pore size distribution curves indicated the presence of mesopores (10–150 Å exhibiting maxima at 35 Å. The maxima were shifted toward higher values by increasing the alumina content. Thermodynamic parameters, ΔH, ΔG and ΔS, were determined by means of inverse gas chromatography using n-hexane as a probe. The untreated and thermally treated materials were tested as solid stationary phases in gas chromatography. The separation efficiency of various non polar and polar compounds was explained in terms of surface texture and thermodynamic parameters.

  8. Chemical warfare agent detection in complex environments with comprehensive two-dimensional gas chromatography

    Science.gov (United States)

    Reichenbach, Stephen E.; Ni, Mingtian; Kottapalli, Visweswara; Visvanathan, Arvind; Ledford, Edward B., Jr.; Oostdijk, John; Trap, Henk C.

    2003-08-01

    Comprehensive two-dimensional gas chromatography (GCxGC) is an emerging technology for chemical separation that provides an order-of-magnitude increase in separation capacity over traditional gas chromatography. GCxGC separates chemical species with two capillary columns interfaced by two-stage thermal desorption. Because GCxGC is comprehensive and has high separation capacity, it can perform multiple traditional analytical methods with a single analysis. GCxGC has great potential for a wide variety of environmental sensing applications, including detection of chemical warfare agents (CWA) and other harmful chemicals. This paper demonstrates separation of nerve agents sarin and soman from a matrix of gasoline and diesel fuel. Using a combination of an initial column separating on the basis of boiling point and a second column separating on the basis of polarity, GCxGC clearly separates the nerve agents from the thousands of other chemicals in the sample. The GCxGC data is visualized, processed, and analyzed as a two-dimensional digital image using a software system for GCxGC image processing developed at the University of Nebraska - Lincoln.

  9. Characterization of chemopreventive agents from the dichloromethane extract of Eurycorymbus cavaleriei by liquid chromatography-ion trap mass spectrometry.

    Science.gov (United States)

    Cheng, Lin; Zhang, Xiaoyu; Zhang, Min; Zhang, Peng; Song, Zhihang; Ma, Zhongjun; Cheng, Yiyu; Qu, Haibin

    2009-06-12

    In the present study, we examined the potential chemopreventive activity of dichloromethane extract of Eurycorymbus cavaleriei by investigating the change of constitutions after incubation with glutathione (GSH). The major constitutions in the dichloromethane extract of E. cavaleriei were cumarin compounds and their cleavage pattern was examined by LC-MS-MS and the characteristic product ions at m/z 206 and 207 were helpful to determine the substitutions of coumarinolignoid compounds. The mechanism of conjugations of 5'-demethylaquillochin and its isomer with GSH was discussed and validated through analysis of the conjugations of reference compound 6-hydroxy-7-methoxycoumarin with GSH by LC-MS-MS and NMR spectrum. The relative ability to induce the detoxification enzyme, NAD(P)H:quinone oxidoreductase 1 (NQO1) of nine coumarin compounds was tested which also showed 5'-demethylaquillochin exhibited the most potential chemopreventive ability. These observations suggest that 5'-demethylaquillochin and its isomer from the dichloromethane extract of E. cavaleriei have potential as chemopreventive agents through induction of detoxification enzymes.

  10. Integrated fiber-mirror ion trap for strong ion-cavity coupling

    International Nuclear Information System (INIS)

    Brandstätter, B.; Schüppert, K.; Casabone, B.; Friebe, K.; Stute, A.; Northup, T. E.; McClung, A.; Schmidt, P. O.; Deutsch, C.; Reichel, J.; Blatt, R.

    2013-01-01

    We present and characterize fiber mirrors and a miniaturized ion-trap design developed to integrate a fiber-based Fabry-Perot cavity (FFPC) with a linear Paul trap for use in cavity-QED experiments with trapped ions. Our fiber-mirror fabrication process not only enables the construction of FFPCs with small mode volumes, but also allows us to minimize the influence of the dielectric fiber mirrors on the trapped-ion pseudopotential. We discuss the effect of clipping losses for long FFPCs and the effect of angular and lateral displacements on the coupling efficiencies between cavity and fiber. Optical profilometry allows us to determine the radii of curvature and ellipticities of the fiber mirrors. From finesse measurements, we infer a single-atom cooperativity of up to 12 for FFPCs longer than 200 μm in length; comparison to cavities constructed with reference substrate mirrors produced in the same coating run indicates that our FFPCs have similar scattering losses. We characterize the birefringence of our fiber mirrors, finding that careful fiber-mirror selection enables us to construct FFPCs with degenerate polarization modes. As FFPCs are novel devices, we describe procedures developed for handling, aligning, and cleaning them. We discuss experiments to anneal fiber mirrors and explore the influence of the atmosphere under which annealing occurs on coating losses, finding that annealing under vacuum increases the losses for our reference substrate mirrors. X-ray photoelectron spectroscopy measurements indicate that these losses may be attributable to oxygen depletion in the mirror coating. Special design considerations enable us to introduce a FFPC into a trapped ion setup. Our unique linear Paul trap design provides clearance for such a cavity and is miniaturized to shield trapped ions from the dielectric fiber mirrors. We numerically calculate the trap potential in the absence of fibers. In the experiment additional electrodes can be used to compensate

  11. Recognition of chitin and proteins in invertebrate cuticles using analytical pyrolysis/gas chromatography and pyrolysis/gas chromatography/mass spectrometry.

    Science.gov (United States)

    Stankiewicz, B A; Van Bergen, P F; Duncan, I J; Carter, J F; Briggs, D E; Evershed, R P

    1996-01-01

    Flash pyrolysis/gas chromatography (py/GC) and py/GC/mass spectrometry (MS) have been utilized to characterize the cuticles of invertebrates chemically. Pyrolysis products have been identified and assigned to specific cuticular components. Acetylpyridones, acetamidofuran, 3-acetamido-5-methylfuran and 3-acetamido-(2 and 4)-pyrones are proposed as characteristic pyrolysis markers for chitin. Pyrolysis products displaying ions of m/z 70, 154, 168, 194 are thought to derive from diketopiperazine structures and provide potential markers for proteins and peptides in which proline, alanine, valine, arginine and glycine are the dominant amino acids. These products, constituting specific pyrolysis markers for invertebrate cuticles, may reflect the amino acid composition of their constituent structural proteins. The source of the various pyrolysis products of proteins has been verified by pyrolysis of reference proteins, peptides and amino acid mixtures. The presence of additional pyrolysis products related directly to histidine and catechol moieties is consistent with the chemical structure and composition proposed for arthropod cuticles based on recent work utilizing solid state 13C and 15N nuclear magnetic resonance. This study constitutes the first comprehensive chemical characterization of the pyrolysis products of invertebrate cuticles and provides the basis for future investigations requiring qualitative screening for cross-linked chitin and proteins in modern and fossil cuticles and in materials, e.g. geopolymers, that may be derived from them.

  12. Identification of Aroma-active Compounds in Essential Oil from Uncaria Hook by Gas Chromatography- Mass Spectrometry and Gas Chromatography-Olfactometry.

    Science.gov (United States)

    Iwasa, Megumi; Nakaya, Satoshi; Maki, Yusuke; Marumoto, Shinsuke; Usami, Atsushi; Miyazawa, Mitsuo

    2015-01-01

    The chemical composition of essential oil extracted from Uncaria Hook ("Chotoko" in Japanese), the branch with curved hook of the herbal medicine Uncaria rhynchophylla has been investigated by GC and GC-MS analyses. Eighty-four compounds, representing 90.8% of the total content was identified in oil obtained from Uncaria Hook. The main components i were (E)-cinnamaldehyde (13.4%), α-copaene (8.0%), methyl eugenol (6.8%), δ-cadinene (5.3%), and curcumene (3.6%). The important key aroma-active compounds in the oil were detected by gas chromatography-olfactometry (GC-O) and aroma extract dilution analysis (AEDA), using the flavor dilution (FD) factor to express the odor potency of each compounds. Furthermore, the odor activity value (OAV) has been used as a measure of the relative contribution of each compound to the aroma of the Uncaria Hook oil. The GC-O and AEDA results showed that α-copaene (FD = 4, OAV = 4376), (E)-linalool oxide (FD = 64, OAV = 9.1), and methyl eugenol (FD = 64, OAV = 29) contributed to the woody and spicy odor of Uncaria Hook oil, whereas furfural (FD = 8, OAV = 4808) contributed to its sweet odor. These results warrant further investigations of the application of essential oil from Uncaria Hook in the phytochemical and medicinal fields.

  13. [Structure determination of alkyd resins by simultaneous pyrolysis methylation gas chromatography-mass spectometry].

    Science.gov (United States)

    Cao, J Y; Fu, D H; Zhang, F; Liang, D

    2000-09-01

    Several types of alkyd resins have been analyzed by simultaneous pyrolysis methylation gas chromatography mass spectrometry (SPM-GC-MS). The samples were mixed with tetramethylammonium hydroxide, and the process included simultaneous pyrolysis derivatization and mass spectrometry determination. SPM-GC-MS conditions: a vertical microfurnace-type pyrolyzer was directly attached to a gas chromatograph-mass spectrometer. About 20 ug of the mixed alkyd resin sample was introduced into the center of the pyrolyzer at 450 degrees C under the flow of helium carrier gas. The inlet mode was split with an injection interval of 10 s and the inlet pressure was 82.7 kPa. The gas chromatograph was fitted with a fused-silica capillary column ( SE-54 30 m x0.25 mm i.d. x 0.25 um). Temperature program settings were: initial temperature, 40 degrees C, hold 2 min; increase at 6 degrees C min 1 to 220 degrees C, hold 14 min; increase at 10 degrees C min 1 to 280 degrees C, hold 8 min. All pyrolysis products referred to were identified by mass spectrometry. The temperature of the ion source was 210 degrees C and that of the transfer line was 250 degrees C. The technique could give additional information about the composition of the dibasic acids, polyols, six types of drying oils, and modified alkyd resins. The method is sensitive, accurate, convenient, and involves minimal sample manipulation.

  14. Photophysics and aggregation effects of a triphenylamine-based dye sensitizer on metal-oxide nanoparticles suspended in an ion trap.

    Science.gov (United States)

    Dryza, Viktoras; Nguyen, Jessica L; Kwon, Tae-Hyuk; Wong, Wallace W H; Holmes, Andrew B; Bieske, Evan J

    2013-12-14

    The photophysical behaviour of a triphenylamine-based organic dye sensitizer (Carbz-PAHTDTT) attached to alumina and titania nanoparticles (labelled Carbz-Al and Carbz-Ti, respectively) is examined in the absence and presence of the chenodeoxycholic acid (CDCA) coadsorber. The experiments are conducted in vacuo by suspending the target dye-sensitized nanoparticles within a quadrupole ion trap, where they are probed with laser radiation to obtain emission spectra and time-resolved excited state decay curves. For Carbz-Al, the dye's emission band is blue-shifted and the excited state lifetime is increased upon the coabsorption of CDCA, effects attributed to reduced dye aggregation. Compared to Carbz-Al, the Carbz-Ti excited state lifetimes are significantly shorter due to excited dye molecules injecting electrons into the titania conduction band. For Carbz-Ti, the electron injection quantum yields for the surfaces with CDCA (CDCA : dye = 25 : 1) and without CDCA are estimated to be 0.87 and 0.71, respectively. The gas-phase results demonstrate that Carbz-PAHTDTT dye aggregates are detrimental to the performance of a dye-sensitized solar cell.

  15. Comprehensive two-dimensional gas chromatography for biogas and biomethane analysis.

    Science.gov (United States)

    Hilaire, F; Basset, E; Bayard, R; Gallardo, M; Thiebaut, D; Vial, J

    2017-11-17

    The gas industry is going to be revolutionized by being able to generate bioenergy from biomass. The production of biomethane - a green substitute of natural gas - is growing in Europe and the United-States of America. Biomethane can be injected into the gas grid or used as fuel for vehicles after compression. Due to various biomass inputs (e.g. agricultural wastes, sludges from sewage treatment plants, etc.), production processes (e.g. anaerobic digestion, municipal solid waste (MSW) landfills), seasonal effects and purification processes (e.g. gas scrubbers, pressure swing adsorption, membranes for biogas upgrading), the composition and quality of biogas and biomethane produced is difficult to assess. All previous publications dealing with biogas analysis reported that hundreds of chemicals from ten chemical families do exist in trace amounts in biogas. However, to the best of our knowledge, no study reported a detailed analysis or the implementation of comprehensive two-dimensional gas chromatography (GC×GC) for biogas matrices. This is the reason why the benefit of implementing two-dimensional gas chromatography for the characterization of biogas and biomethane samples was evaluated. In a first step, a standard mixture of 89 compounds belonging to 10 chemical families, representative of those likely to be found, was used to optimize the analytical method. A set consisting of a non-polar and a polar columns, respectively in the first and the second dimension, was used with a modulation period of six seconds. Applied to ten samples of raw biogas, treated biogas and biomethane collected on 4 industrial sites (two MSW landfills, one anaerobic digester on a wastewater treatment plant and one agricultural biogas plant), this analytical method provided a "fingerprint" of the gases composition at the molecular level in all biogas and biomethane samples. Estimated limits of detection (far below the μgNm -3 ) coupled with the resolution of GC×GC allowed the comparison

  16. Relationship of Ambient Atmosphere and Biological Aerosol Responses from a Fielded Pyrolysis-Gas Chromatography-Ion Mobility Spectrometry Bioanalytical Detector

    National Research Council Canada - National Science Library

    Snyder, A

    2003-01-01

    .... A pyrolysis-gas chromatography-ion mobility spectrometry stand-alone bioaerosol system was interfaced to an aerosol concentrator to collect ambient background aerosols and produce bioanalytical...

  17. Detailed analysis of petroleum cuts by multidimensional gas chromatography; Analyse detaillee de coupes petrolieres par chromatographie en phase gazeuse multidimensionnelle

    Energy Technology Data Exchange (ETDEWEB)

    Vendeuvre, C.

    2006-01-15

    The limitations of petroleum resources implying a better valorisation of crude oil through the optimisation of production, refinery and petrochemistry processes, as well as the environmental regulations have strengthened the necessity of more detailed characterisation of petroleum products. In order to take up this challenge, efficient analytical tools have to be developed. This work demonstrates that comprehensive two-dimensional gas chromatography (GCxGC) constitutes a major advance compared to GC owing to its improved resolution power and to the structured chromatograms indicating the polarity and the volatility of hydrocarbons. The principle of GCxGC is based on the analysis of a whole sample in two independent dimensions of separation achieved using two GC columns of different selectivities; between the two columns a modulator device samples, focuses and re-injects small portions of the effluent from the first column into the second one. Since its introduction in 1991, GCxGC has known a rapid growth and has received a wide acceptance by the analytical science community. The competitive situation has considerably evolved during this thesis with the introduction of commercial systems and the two first sessions of an international symposium dedicated to this technique (Volendam, 2003 and Atlanta, 2004). The key points of the thesis concern the development of a GCxGC prototype system using dual jets CO{sub 2} technology and a data processing program; the evaluation of a retention model allowing a rational choice of operating conditions; and the application of this technique to various and complex issues. Thus, effluents from petrochemistry, refinery or pollution areas have been analysed according to the chemical classes of hydrocarbons and to their number of carbon atoms; a new method for obtaining distillation curves for each chemical group was also presented. Furthermore, the hyphenation of GCxGC with a specific sulphur detector revealed a great interest for

  18. Charge state dependent fragmentation of gaseous [alpha]-synuclein cations via ion trap and beam-type collisional activation

    Science.gov (United States)

    Chanthamontri, Chamnongsak; Liu, Jian; McLuckey, Scott A.

    2009-06-01

    Ions derived from nano-electrospray ionization (nano-ESI) of [alpha]-synuclein, a 14.5 kDa, 140 amino acid residue protein that is a major component of the Lewy bodies associated with Parkinson's disease, have been subjected to ion trap and beam-type collisional activation. The former samples products from fragmentation at rates generally lower than 100 s-1 whereas the latter samples products from fragmentation at rates generally greater than 103 s-1. A wide range of protein charge states spanning from as high as [M+17H]17+ to as low as [M+4H]4+ have been formed either directly from nano-ESI or via ion/ion proton transfer reactions involving the initially formed protein cations and have been subjected to both forms of collision-induced dissociation (CID). The extent of sequence information (i.e., number of distinct amide bond cleavages) available from either CID method was found to be highly sensitive to protein precursor ion charge state. Furthermore, the relative contributions of the various competing dissociation channels were also dependent upon precursor ion charge state. The qualitative trends in the changes in extent of amide bond cleavages and identities of bonds cleaved with precursor ion charge state were similar for two forms of CID. However, for every charge state examined, roughly twice the primary sequence information resulted from beam-type CID relative to ion trap CID. For example, evidence for cleavage of 86% of the protein amide bonds was observed for the [M+9H]9+ precursor ion using beam-type CID whereas 41% of the bonds were cleaved for the same precursor ion using ion trap CID. The higher energies required to drive fragmentation reactions at rates necessary to observe products in the beam experiment access more of the structurally informative fragmentation channels, which has important implications for whole protein tandem mass spectrometry.

  19. A Dual Source Ion Trap Mass Spectrometer for the Mars Organic Molecule Analyzer of ExoMars 2018

    Science.gov (United States)

    Brickerhoff, William B.; vanAmerom, F. H. W.; Danell, R. M.; Arevalo, R.; Atanassova, M.; Hovmand, L.; Mahaffy, P. R.; Cotter, R. J.

    2011-01-01

    We present details on the objectives, requirements, design and operational approach of the core mass spectrometer of the Mars Organic Molecule Analyzer (MOMA) investigation on the 2018 ExoMars mission. The MOMA mass spectrometer enables the investigation to fulfill its objective of analyzing the chemical composition of organic compounds in solid samples obtained from the near surface of Mars. Two methods of ionization are realized, associated with different modes of MOMA operation, in a single compact ion trap mass spectrometer. The stringent mass and power constraints of the mission have led to features such as low voltage and low frequency RF operation [1] and pulse counting detection.

  20. Structure and dynamics of highly charged heavy ions studied with the electron beam ion trap in Tokyo

    International Nuclear Information System (INIS)

    Nakamura, Nobuyuki; Hu, Zhimin; Watanabe, Hirofumi; Li, Yueming; Kato, Daiji; Currell, Fred J.; Tong Xiaomin; Watanabe, Tsutomu; Ohtani, Shunsuke

    2011-01-01

    In this paper, we present the structure and the dynamics of highly charged heavy ions studied through dielectronic recombination (DR) observations performed with the Tokyo electron beam ion trap. By measuring the energy dependence of the ion abundance ratio in the trap at equilibrium, we have observed DR processes for open shell systems very clearly. Remarkable relativistic effects due to the generalized Breit interaction have been clearly shown in DR for highly charged heavy ions. We also present the first result for the coincidence measurement of two photons emitted from a single DR event.

  1. Comprehensive lipidome analysis by shotgun lipidomics on a hybrid quadrupole-orbitrap-linear ion trap mass spectrometer

    DEFF Research Database (Denmark)

    Almeida, Reinaldo; Pauling, Josch Konstantin; Sokol, Elena

    2015-01-01

    , including its high resolution power unsurpassed by any other contemporary Orbitrap instrumentation, its dynamic quantification range and its efficacy for in-depth structural characterization of molecular lipid species by quadrupole-based higher-energy collisional dissociation (HCD), and ion trap...... and CID and ITMS(3) analysis utilizing dual CID for in-depth structural characterization of molecular glycerophospholipid species. The performance of the MS(ALL) method was benchmarked in a comparative analysis of mouse cerebellum and hippocampus. This analysis demonstrated extensive lipidome...

  2. Production of a helium beam in a focused ion beam machine using an electron beam ion trap

    International Nuclear Information System (INIS)

    Ullmann, F.; Grossmann, F.; Ovsyannikov, V. P.; Gierak, J.; Zschornack, G.

    2007-01-01

    Gallium liquid-metal ion sources that have been introduced in the late 1970s have allowed the development of a new class of micro- and nanofabrication tools collectively denominated as focused ion beam (FIB) machines. To investigate the potential of a helium beam in such a FIB instrument the authors have tested a room-temperature electron beam ion trap coupled with a high resolution FIB machine. In this letter they present their first results in target imaging using a helium beam with a resolution that allows to account for a beam diameter in the submicrometer range

  3. Chemical characterization of individual microparticles using an ion trap: real-time chemical analysis of aerosol particles

    International Nuclear Information System (INIS)

    Yang, Mo; Whitten, W.B.; Reilly, P.T.A.; Gieray, R.; Ramsey, J.M.

    1996-01-01

    This paper describes initial experiments to perform laser ablation mass spectrometry in real time on airborne microparticles. The microparticles are sampled directly from the air by a particle inlet system into the vacuum chamber of a mass spectrometer. An incoming particle is detected as it passes through two CW laser beams and a pulsed laser is triggered to intercept the particle for laser ablation/ionization in the mass spectrometer. The initial studies were made with an existing ion trap mass spectrometer with the particle sampling occurring at the center of the trap electrodes. Performance of the inlet system, particle detection, and preliminary results are described

  4. Chemical characterization of individual microparticles using an ion trap: real-time chemical analysis of aerosol particles

    Energy Technology Data Exchange (ETDEWEB)

    Yang, Mo; Whitten, W.B.; Reilly, P.T.A.; Gieray, R.; Ramsey, J.M.

    1996-10-01

    This paper describes initial experiments to perform laser ablation mass spectrometry in real time on airborne microparticles. The microparticles are sampled directly from the air by a particle inlet system into the vacuum chamber of a mass spectrometer. An incoming particle is detected as it passes through two CW laser beams and a pulsed laser is triggered to intercept the particle for laser ablation/ionization in the mass spectrometer. The initial studies were made with an existing ion trap mass spectrometer with the particle sampling occurring at the center of the trap electrodes. Performance of the inlet system, particle detection, and preliminary results are described.

  5. The Mars Organic Molecule Analyser : in situ analysis of organic compounds on Mars by Gas Chromatography-Mass Spectrometry.

    Science.gov (United States)

    Buch, Arnaud; Sternberg, Robert; Freissinet, Caroline; Pinnick, Veronika; Szopa, Cyril; Coll, Patrice; Geffroy-Rodier, Claude; Raulin, Francois; Goesmann, Fred

    The search for signs of past or present life is one of the primary goals of the future Mars exploratory missions. With this aim the Mars Organic Molecule Analyzer (MOMA) experiment of the ExoMars 2016-2018 next coming joint ESA/NASA mission is designed to perform the in situ analysis of exobiological organic molecules of exobiological interest in the Martian soil such as amino acids, carboxylic acids, nucleobases or polycyclic aromatic hydrocarbons (PAHs). With the aim to separate and detect organic compounds from Martian soil, US and European teams have respectively built an ion trap mass spectrometer and a gas chromatograph. The mass spectrometer prototype has been coupled with the gas chromatograph prototype which is able to work in standalone mode by using a TCD detector. A GC-MS compatible sample processing system (SPS) allowing the extraction and the chemical transformation of the organic compounds from the soil, within space compatible operating conditions, has also been devel-oped. The sample processing is performed in an oven, dedicated to the MOMA experiment containing the solid sample (50-100mg). The internal temperature of which can be ranged from 20 to 1000 C. The extraction step is achieved by using thermodesorption in the range of 100 to 300C for 5 to 20 min. Then, the chemical derivatization and/or thermochemolysis of the extracted compounds is performed directly on the soil with a mixture of MTBSTFA-DMF, TMAH or DMF-DMA solution when enantiomeric separation is required. By decreasing the polarity of the target molecules, this step allows their volatilization at a temperature below 250C without any chemical degradation. Once derivatized, the volatile target molecules are trapped in a cold and chemical trap and promptly desorbed into the gas chromatograph coupled with a mass spectrometer. Preliminary tests, performed on Martian analogue soils (Atacama), with the MOMA SPS-GC/MS experiment, allowed the detection of organic compounds such as amino and

  6. Seeking organic compounds on Mars : in situ analysis of organic compounds by Gas Chromatography-Mass Spectrometry on MOMA experiment

    Science.gov (United States)

    Buch, A.; Freissinet, C.; Sternberg, R.; Pinnick, V.; Szopa, C.; Coll, P. J.; Rodier, C.; Garnier, C.; Steininger, H.; Moma Team

    2010-12-01

    The search for signs of past or present life is one of the primary goals of future Mars exploratory missions. The Mars Organic Molecule Analyzer (MOMA) experiment of the ExoMars mission (set to launch 2016-2018) is a joint venture by the European Space Agency and NASA to develop a sensitive detector for organics on Mars. MOMA will be one of the main analytical instruments aboard the ExoMars Rover aimed at characterizing possible “signs-of-life molecules” in the Martian environment such as amino acids, carboxylic acids, nucleobases or polycyclic aromatic hydrocarbons (PAHs). With the aim to separate and detect organic compounds from Martian soil, the French MOMA team has built a gas chromatograph able to work in standalone mode by using a TCD detector. The gas chromatograph can also be coupled with an ion trap mass spectrometer developed by the US MOMA team. Moreover, a GC-MS compatible sample processing system (SPS) allowing the extraction and the chemical transformation of the organic compounds from the soil, that fits within space flight conditions, has also been developed. The sample processing is performed in an oven, dedicated to the MOMA experiment containing the solid sample (50-100mg). The internal temperature of oven can be ranged from 20 to 1000 °C which allows for pyrolysis, thermochemolysis or derivatization. The organic extraction step is achieved by using thermodesorption in the range of 100 to 300°C for 0.5 to 5 min. Then, the chemical derivatization and/or thermochemolysis of the extracted compounds is performed directly on the soil with a mixture of MTBSTFA-DMF, TMAH or DMF-DMA solution when enantiomeric separation is required. By decreasing the polarity of the target molecules, this step allows for their volatilization at a temperature below 250°C without any chemical degradation. Once derivatized, the volatile target molecules are trapped in a cold chemical trap and promptly desorbed into the gas chromatograph coupled to the mass

  7. [Analysis of volatile oil in Illicium verum fruit by on-line coupled packed capillary liquid chromatography/capillary gas chromatography].

    Science.gov (United States)

    Wang, Xiaochun; Wang, Hanwen; Ma, Jiping; Xu, Ye; Guan, Yafeng

    2004-03-01

    Volatile oil in Illicillm Verum Fruit was analyzed by on-line coupled packed capillary high performance liquid chromatography/capillary gas chromatography (micro-HPLC-CGC). A micro-HPLC column of 250 mm x 0.32 mm i.d. packed with 5 microm cyano-bonded silica stationary phase was used for group separation. n-Hexane/acetonitrile/dichloromethane (80:8:12, v/v) was used as mobile phase at a flow rate of 1.8 microL/min. Five groups of eluents from the micro-HPLC were collected and stored in a multi-loop interface, which were then transferred to a capillary gas chromatograph sequentially for further analysis. A 10 m x 0.53 mm i.d. retention gap connected with a 30 m x 0.53 mm i.d. x 1.0 microm SE-54 analytical column was used for CGC analysis. In-column splitless injection mode was adopted for better quantitation and manipulation of chromatograms. Five chromatograms were obtained and compared with the result of direct CGC analysis of the same sample. It was found that there were at least 3 new compounds that were not found nor separated before by conventional capillary gas chromatography/mass spectrometry method.

  8. Compound-specific hydrogen isotope analysis of fluorine-, chlorine-, bromine- and iodine-bearing organics using gas chromatography-chromium-based high-temperature conversion (Cr/HTC) isotope ratio mass spectrometry.

    Science.gov (United States)

    Renpenning, Julian; Schimmelmann, Arndt; Gehre, Matthias

    2017-07-15

    The conventional high-temperature conversion (HTC) approach towards hydrogen compound-specific isotope analysis (CSIA) of halogen-bearing (F, Cl, Br, I) organics suffers from incomplete H 2 yields and associated hydrogen isotope fractionation due to generation of HF, HCl, HBr, and HI byproducts. Moreover, the traditional off-line combustion of highly halogenated compounds results in incomplete recovery of water as an intermediary compound for hydrogen isotope ratio mass spectrometry (IRMS), and hence also leads to isotope fractionation. This study presents an optimized chromium-based high-temperature conversion (Cr/HTC) approach for hydrogen CSIA of various fluorinated, chlorinated, brominated and iodinated organic compounds. The Cr/HTC approach is fast, economical, and not affected by low H 2 yields and associated isotope fractionation. The performance of the modified gas chromatography/chromium-based high-temperature conversion (GC-Cr/HTC) system was monitored and optimized using an ion trap mass spectrometer. Quantitative conversion of organic hydrogen into H 2 analyte gas was achieved for all halogen-bearing compounds. The corresponding accuracy of CSIA was validated using (i) manual dual-inlet (DI)-IRMS after off-line conversion into H 2 , and (ii) elemental analyzer (EA)-Cr/HTC-IRMS (on-line conversion). The overall hydrogen isotope analysis of F-, Cl-, Br- and I-bearing organics via GC-Cr/HTC-IRMS achieved a precision σ ≤ 3 mUr and an accuracy within ±5 mUr along the VSMOW-SLAP scale compared with the measured isotope compositions resulting from both validation methods, off-line and on-line. The same analytical performance as for single-compound GC-Cr/HTC-IRMS was achieved compound-specifically for mixtures of halogenated organics following GC separation to baseline resolution. GC-Cr/HTC technology can be implemented in existing analytical equipment using commercially available materials to provide a versatile tool for hydrogen CSIA of halogenated and

  9. Metal Nanoparticles Protected with Monolayers: Applications for Chemical Vapor Sensing and Gas Chromatography

    Energy Technology Data Exchange (ETDEWEB)

    Grate, Jay W.; Nelson, David A.; Skaggs, Rhonda L.; Synovec, Robert E.; Gross, Gwen M.

    2004-03-31

    Nanoparticles and nanoparticle-based materials are of considerable interest for their unique properties and their potential for use in a variety of applications. Metal nanoparticles, in which each particle’s surface is coated with a protective organic monolayer, are of particular interest because the surface monolayer stabilizes them relative to aggregation and they can be taken up into solutions.(1-4) As a result they can be processed into thin films for device applications. We will refer to these materials as monolayer-protected nanoparticles, or MPNs. Typically the metal is gold, the organic layer is a self-assembled thiol layer, and this composition will be assumed throughout the remainder of this chapter. A diversity of materials and properties is readily accessible by straightforward synthetic procedures, either by the structures of the monolayer-forming thiols used in the synthesis or by post-synthetic modifications of the monolayers. A particularly promising application for these materials is as selective layers on chemical vapor sensors. In this role, the thin film of MPNs on the device surface serves to collect and concentrate gas molecules at the sensor’s surface. Their sorptive properties also lend them to use as new nanostructured gas chromatographic stationary phases. This chapter will focus on the sorptive properties of MPNs as they relate to chemical sensors and gas chromatography.

  10. Time distribution of adsorption entropy of gases on heterogeneous surfaces by reversed-flow gas chromatography.

    Science.gov (United States)

    Katsanos, Nicholas A; Kapolos, John; Gavril, Dimitrios; Bakaoukas, Nicholas; Loukopoulos, Vassilios; Koliadima, Athanasia; Karaiskakis, George

    2006-09-15

    The reversed-flow gas chromatography (RF-GC) technique has been applied to measure the adsorption entropy over time, when gaseous pentane is adsorbed on the surface of two solids (gamma-alumina and a silica supported rhodium catalyst) at 393.15 and 413.15K, respectively. Utilizing experimental chromatographic data, this novel methodology also permits the simultaneous measurement of the local adsorption energy, epsilon, local equilibrium adsorbed concentration, c(s)(*), and local adsorption isotherm, theta(p, T, epsilon) in a time resolved way. In contrast with other inverse gas chromatographic methods, which determine the standard entropy at zero surface coverage, the present method operates over a wide range of surface coverage taking into account not only the adsorbate-adsorbent interaction, but also the adsorbate-adsorbate interaction. One of the most interesting observations of the present work is the fact that the interaction of n-pentane is spontaneous on the Rh/SiO(2) catalyst for a very short time interval compared to that on gamma-Al(2)O(3). This can explain the different kinetic behavior of each particular gas-solid system, and it can be attributed to the fact that large amounts of n-C(5)H(12) are present on the active sites of the Rh/SiO(2) catalyst compared to those on gamma-Al(2)O(3), as the local equilibrium adsorbed concentration values, c(s)(*), indicate.

  11. Compound-specific chlorine isotope analysis: a comparison of gas chromatography/isotope ratio mass spectrometry and gas chromatography/quadrupole mass spectrometry methods in an interlaboratory study.

    Science.gov (United States)

    Bernstein, Anat; Shouakar-Stash, Orfan; Ebert, Karin; Laskov, Christine; Hunkeler, Daniel; Jeannottat, Simon; Sakaguchi-Söder, Kaori; Laaks, Jens; Jochmann, Maik A; Cretnik, Stefan; Jager, Johannes; Haderlein, Stefan B; Schmidt, Torsten C; Aravena, Ramon; Elsner, Martin

    2011-10-15

    Chlorine isotope analysis of chlorinated hydrocarbons like trichloroethylene (TCE) is of emerging demand because these species are important environmental pollutants. Continuous flow analysis of noncombusted TCE molecules, either by gas chromatography/isotope ratio mass spectrometry (GC/IRMS) or by GC/quadrupole mass spectrometry (GC/qMS), was recently brought forward as innovative analytical solution. Despite early implementations, a benchmark for routine applications has been missing. This study systematically compared the performance of GC/qMS versus GC/IRMS in six laboratories involving eight different instruments (GC/IRMS, Isoprime and Thermo MAT-253; GC/qMS, Agilent 5973N, two Agilent 5975C, two Thermo DSQII, and one Thermo DSQI). Calibrations of (37)Cl/(35)Cl instrument data against the international SMOC scale (Standard Mean Ocean Chloride) deviated between instruments and over time. Therefore, at least two calibration standards are required to obtain true differences between samples. Amount dependency of δ(37)Cl was pronounced for some instruments, but could be eliminated by corrections, or by adjusting amplitudes of standards and samples. Precision decreased in the order GC/IRMS (1σ ≈ 0.1‰), to GC/qMS (1σ ≈ 0.2-0.5‰ for Agilent GC/qMS and 1σ ≈ 0.2-0.9‰ for Thermo GC/qMS). Nonetheless, δ(37)Cl values between laboratories showed good agreement when the same external standards were used. These results lend confidence to the methods and may serve as a benchmark for future applications. © 2011 American Chemical Society

  12. Pyrolysis-gas chromatography-mass spectrometry of isolated, synthetic and degraded lignins

    Energy Technology Data Exchange (ETDEWEB)

    Saiz-Jimenez, C.; De Leeuw, J.W.

    1984-01-01

    Curie-point pyrolysis-gas chromatography-mass spectrometry was applied to study the chemical structure of sound and fungus degraded, industrial and synthetic lignins. Pyrolysis products reflected in some detail the structural units present in the lignin polymer. Thus, sound spruce lignin yielded trans-isoeugenol coniferaldehyde and trans-coniferyl alcohol as major pyrolysis products. Biodegraded lignin yielded oxidized units, including vanillin, acetoguaiacone, methyl vanillate, propioguaiacone, vanilloyl methyl ketone and vanillic acid as major products. Kraft lignin also showed evidence of oxidation, although not as much as the biodegraded lignin. Major products from this industrial lignin were guaiacol, methylguaiacol, vinylguaiacol and homovanillic acid. Results indicated that synthetic lignin duplicates fairly well the structure of natural lignin. However, coniferylaldehyde and trans-coniferyl alcohol were the dominant products only from the synthetic lignin, indicating the presence of large amounts of coniferyl alcohol and coniferylaldehyde end groups. 21 references.

  13. A study of the thermal activation of synthetic zeolites (molecular sieve) for gas-solid chromatography

    International Nuclear Information System (INIS)

    Walker, J.A.J.

    1978-10-01

    The thermal activation of synthetic zeolites from two sources has been investigated with reference to the adsorption chromatography of inorganic gases. It was found that the heats of adsorption for oxygen and carbon monoxide increased with activation temperature. Limits of detection for oxygen in argon and conversely argon in oxygen were determined as well as the chromatographic stability of the activated zeolite. The practical implications and importance of the results are discussed and the application to the analysis of fast reactor blanket gas is mentioned. An explanation is proposed for the adsorption behaviour of these activated materials, based on an electrostatic mechanism, and this has suggested a reason for the separation characteristics of oxygen and argon on polar zeolites. Further work is identified including the investigation of energy states of the oxygen molecule adsorbed on activated zeolite by means of ultra-violet photoelectron spectroscopy. (author)

  14. Verification of chemical composition of commercially available propolis extracts by gas chromatography-mass spectrometry analysis.

    Science.gov (United States)

    Czyżewska, Urszula; Konończuk, Joanna; Teul, Joanna; Drągowski, Paweł; Pawlak-Morka, Renata; Surażyński, Arkadiusz; Miltyk, Wojciech

    2015-05-01

    Propolis is a resin that is collected by honeybees from various plant sources. Due to its pharmacological properties, it is used in commercial production of nutritional supplements in pharmaceutical industry. In this study, gas chromatography-mass spectrometry was applied for quality control analysis of the three commercial specimens containing aqueous-alcoholic extracts of bee propolis. More than 230 constituents were detected in analyzed products, including flavonoids, chalcones, cinnamic acids and their esters, phenylpropenoid glycerides, and phenylpropenoid sesquiterpenoids. An allergenic benzyl cinnamate ester was also identified in all tested samples. This analytical method allows to evaluate biological activity and potential allergenic components of bee glue simultaneously. Studies on chemical composition of propolis samples may provide new approach to quality and safety control analysis in production of propolis supplementary specimens.

  15. Gasoline quality prediction using gas chromatography and FTIR spectroscopy: An artificial intelligence approach

    Energy Technology Data Exchange (ETDEWEB)

    K. Brudzewski; A. Kesik; K. Kolodziejczyk; U. Zborowska; J. Ulaczyk [Warsaw University of Technology, Warsaw (Poland). Department of Chemistry

    2006-03-01

    This paper reports on analysis of 45 gasoline samples with different qualities, namely, octane number and chemical composition. Measurements of data from gas chromatography and IR (FTIR) spectroscopy are used to gasoline quality prediction and classification. The data were processed using principal component analysis (PCA) and fuzzy C means (FCM) algorithm. The data were then analyzed following the neural network paradigms, hybrid neural network and support vector machines (SVM) classifier. The IR spectra were compressed and de-noised by the discrete wavelet analysis. Using the hybrid neural network and multi linear regression method (MLRM), excellent correlation between chemical composition of the gasoline samples and predicted value of the octane number was obtained. About 100% correct classification for six different categories of the gasoline was achieved, each of which has different qualities. 9 refs., 4 figs., 5 tabs.

  16. Gas chromatography-mass spectrometry identification of photoproducts of hexahydroquinoline derivatives: potential calcium channel antagonists.

    Science.gov (United States)

    Mielcarek, Jadwiga; Matłoka, Agnieszka

    2005-05-05

    Photodegradation products of hexahydroquinoline derivatives (HHQ) have been analysed with gas chromatography-mass spectrometry (GC-MS). The photodegradation was carried out under the conditions recommended in the first version of the document issued by the International Conference on Harmonization (ICH), currently in force in the studies of photochemical stability of drugs and therapeutic substances. The study was performed on the compounds having two chlorine atoms at different positions of the phenyl ring. Photodegradation of dichlorophenyl derivatives of HHQ resulted in formation of one or three photoproducts. The main product of their decomposition was aromatic compound formed as a result of dehydrogenation of the dihydropyridine ring. The most often observed fragmentation pathway of the photoproducts formed was elimination of methyl and methoxy radicals from the ester groups. The fragmentation of the photoproducts containing one chlorine atom at the ortho-position of the phenyl ring occurred through elimination of chlorine radical.

  17. Multiresidue determination of pesticides in fruit and vegetables by gas chromatography/tandem mass spectrometry.

    Science.gov (United States)

    Gamón, M; Lleó, C; Ten, A; Mocholí, F

    2001-01-01

    Pesticide residues in fruit and vegetables were determined by gas chromatography/tandem mass spectrometry (GC/MS/MS). Electron impact (EI)/MS/MS and chemical ionization (CI)/MS/MS were developed for 80 compounds, including organochlorine, organophosphorus, organonitrogen, and pyrethroids, providing unambiguous spectral confirmation for these complex matrixes. Residues were extracted from samples with acetone followed by a mixture of dichloromethane-petroleum ether. Two injections per sample were required for analysis of the entire pesticide list by EI/MS/MS and CI/MS/MS. Initial steps involving cleanup and concentration of extracts were eliminated. The excellent selectivity and good linearity allowed quantification and identification of low levels of pesticides in the most difficult matrixes. The method has been used for routine analysis of many vegetables.

  18. (Vapour + liquid) equilibria of ternary systems with ionic liquids using headspace gas chromatography

    Energy Technology Data Exchange (ETDEWEB)

    Mokhtarani, Babak [Chemistry and Chemical Engineering Research Center of Iran, P.O. Box 14335-186, Tehran (Iran, Islamic Republic of); Gmehling, Juergen, E-mail: gmehling@tech.chem.uni-oldenburg.d [Carl von Ossietzky Universitaet Oldenburg, Technische Chemie, D-26111 Oldenburg (Germany)

    2010-08-15

    (Vapour + liquid) equilibrium (VLE) data for the ternary systems (hexane + benzene), (hexane + cyclohexane), (benzene + cyclohexane), and (ethanol + water) with an ionic liquid as entrainer for extractive distillation were measured by headspace gas chromatography. As ionic liquids, 1-hexyl-3-methyl-imidazolium bis (trifluoromethyl-sulfonyl) imide [HMIM][BTI], 1-octyl-3-methyl-imidazolium bis (trifluoromethyl-sulfonyl) imide [OMIM][BTI], 1-octyl-3-methyl-imidazolium trifluoro-methanesulfonate [OMIM][OTF], and 1-butyl-3-methyl-imidazolium trifluoro-methanesulfonate [BMIM][OTF] were used. The experimental data show that the ionic liquids investigated have a great influence on the separation factors of the systems (hexane + benzene), (hexane + cyclohexane), and (benzene + cyclohexane). The experimental data were compared with the predicted results using mod. UNIFAC (Do). The predicted results are in good agreement with the experimental data.

  19. Profiling of plasma metabolites in canine oral melanoma using gas chromatography-mass spectrometry.

    Science.gov (United States)

    Kawabe, Mifumi; Baba, Yuta; Tamai, Reo; Yamamoto, Ryohei; Komori, Masayuki; Mori, Takashi; Takenaka, Shigeo

    2015-08-01

    Malignant melanoma is one of the most common and aggressive tumors in the oral cavity of dog. The tumor has a poor prognosis, and methods for diagnosis and prediction of prognosis after treatment are required. Here, we examined metabolite profiling using gas chromatography-mass spectrometry (GC-MS) for development of a discriminant model for evaluation of prognosis. Metabolite profiles were evaluated in healthy and melanoma plasma samples using orthogonal projection to latent structure using discriminant analysis (OPLS-DA). Cases that were predicted to be healthy using the OPLS discriminant model had no advanced lesions after radiation therapy. These results indicate that metabolite profiling may be useful in diagnosis and prediction of prognosis of canine malignant melanoma.

  20. Gas chromatography-mass spectrometric identification of iodine species arising from photo-chemical vapor generation

    Energy Technology Data Exchange (ETDEWEB)

    Grinberg, Patricia; Mester, Zoltan [Institute for National Measurements Standards, National Research Council Canada, Ottawa, Ontario, K1A 0R6 (Canada); D' Ulivo, Alessandro [Institute for Chemical and Physical Processes, National Research Council, Via G. Moruzzi 1, Pisa, 56124 (Italy); Sturgeon, Ralph E. [Institute for National Measurements Standards, National Research Council Canada, Ottawa, Ontario, K1A 0R6 (Canada)], E-mail: ralph.sturgeon@nrc.ca

    2009-07-15

    Ultraviolet irradiation of aqueous solutions of iodide/iodate ion containing low molecular weight organic acids generates volatile iodine species that are amenable to detection by atomic spectrometry. In the presence of formic, acetic or propionic acids, photo-chemical generation results in the formation of HI, methyl- and ethyl-iodide respectively, the latter two products being directly identified by gas chromatography-mass spectrometry. Deuterium and {sup 13}C-labeled reagents were employed to elucidate the provenance of the alkyl group. Use of {sup 13}CH{sub 3}-COOH produced {sup 13}CH{sub 3}-I; deuterated acetic acid (D{sub 3}C-COOD) resulted in the formation of CD{sub 3}-I. These observations indicate direct transfer of the alkyl group from the carboxylic acid to iodide, consistent with the suggestion that the mechanism of synthesis involves radical induced reactions.

  1. Gas chromatography-mass spectrometric identification of iodine species arising from photo-chemical vapor generation

    Science.gov (United States)

    Grinberg, Patricia; Mester, Zoltan; D'Ulivo, Alessandro; Sturgeon, Ralph E.

    2009-07-01

    Ultraviolet irradiation of aqueous solutions of iodide/iodate ion containing low molecular weight organic acids generates volatile iodine species that are amenable to detection by atomic spectrometry. In the presence of formic, acetic or propionic acids, photo-chemical generation results in the formation of HI, methyl- and ethyl-iodide respectively, the latter two products being directly identified by gas chromatography-mass spectrometry. Deuterium and 13C-labeled reagents were employed to elucidate the provenance of the alkyl group. Use of 13CH 3-COOH produced 13CH 3-I; deuterated acetic acid (D 3C-COOD) resulted in the formation of CD 3-I. These observations indicate direct transfer of the alkyl group from the carboxylic acid to iodide, consistent with the suggestion that the mechanism of synthesis involves radical induced reactions.

  2. Detecting naphthenic acids in waters by gas chromatography-mass spectrometry.

    Science.gov (United States)

    Merlin, Mireya; Guigard, Selma E; Fedorak, Phillip M

    2007-01-26

    Naphthenic acids (general formula C(n)H(2n+Z)O(2)) are water-soluble, toxic compounds found in petroleum and bitumen. Some of the current methods for detecting these acids in waters depend on measuring the presence of the carboxylic acid functional group, and therefore many of these methods also detect naturally occurring carboxylic acids that are not naphthenic acids. We report a procedure that includes liquid-liquid extraction, cleanup, and derivatization to form t-butyldimethylsilyl esters prior to gas chromatography-mass spectrometry (GC-MS) analysis. Using low- and high-resolution MS to detect the ion C(15)H(27)O(2)Si(+) (nominal m/z=267) is an excellent indicator of the presence of naphthenic acids at concentrations > or =10microgL(-1).

  3. Determination of d-limonene in adipose tissue by gas chromatography-mass spectrometry

    Science.gov (United States)

    Miller, Jessica A.; Hakim, Iman A.; Thomson, Cynthia; Thompson, Patricia; Chow, H-H. Sherry

    2008-01-01

    We developed a novel method for analyzing d-limonene levels in adipose tissue. Fat samples were subjected to saponification followed by solvent extraction. d-Limonene in the sample extract was analyzed using gas chromatography-mass spectrometry (GC-MS) with selected ion monitoring. Linear calibration curves were established over the mass range of 79.0-2,529 ng d-limonene per 0.1 grams of adipose tissue. Satisfactory within day precision (RSD 6.7 to 9.6%) and accuracy (% difference of −2.7 to 3.8%) and between day precision (RSD 6.0 to 10.7%) and accuracy (% difference of 1.8 to 2.6%) were achieved. The assay was successfully applied to human fat biopsy samples from a d-limonene feeding trial. PMID:18571481

  4. Characterization of free and bound fatty acids in human gallstones by capillary gas liquid chromatography

    International Nuclear Information System (INIS)

    Channa, N.A.; Khand, F.D.; Noorani, M.A.; Bhanger, M.I.

    2002-01-01

    Forty-four human gallstone samples either of pure cholesterol or cholesterol and bilirubin were randomly selected and analyzed by capillary gas liquid chromatography for the relative percentage composition of free and total fatty acids. The results showed that bound fatty acids were present in higher amounts than the free fatty acids. Amongst the bound fatty acids the percentage occurrence for palmitic acid was highest followed by stearic, oleic, linoleic and myristic acids. Fatty acids myristic, palmitic and linoleic were present in higher amounts in cholesterol gallstones, whereas stearic acid in cholesterol and bilirubin gallstones. When compared, no significant difference (p < 0.05) in the levels of free and bound fatty acids were seen in gallstones of males and females. The results suggest that bound fatty acids have a role to play in the structure of gallstones. (author)

  5. Estimation of Fatty Acids in Corn Oil by Gas Capillary Chromatography

    International Nuclear Information System (INIS)

    Kamal, Mohammad A; Klein Peter

    2007-01-01

    Fatty acids provide energy as well as play important role in some cellular structures like cell membrane and certain hormones. Saturated fatty acids are usually found in animal products and in some vegetable oils as well. These saturated fatty acids may be a factor in weight gain and obesity but eating them in moderate amounts may not be damaging to health of every person. Monounsaturated fatty acids can lower blood levels of low density lipoprotein cholesterol and have potential to increase blood levels of high density lipoprotein cholesterol and by this way plays protective role against heart disease. The omega 3 and 6 fatty acids have vital roles in many biological systems such as nervous, immune, cardiovascular, dermal and vision systems. Therefore, it is essential to optimize the instrumental conditions and column specification for the estimation of various fatty acids in the oil, which was considered in the current study using Gas Capillary Chromatography. (author)

  6. Determination of Chlorpyrifos in Human Blood by Gas Chromatography-Mass Spectrometry

    Directory of Open Access Journals (Sweden)

    Xinhua Dai

    2017-01-01

    Full Text Available Gas chromatography-mass spectrometry method was developed for the qualitative and quantitative analyses of chlorpyrifos in human blood samples. The chlorpyrifos and parathion (internal standard in human blood were extracted with a mixed solvent of hexane and acetonitrile. Chlorpyrifos was well separated from the internal standard. The linear range of chlorpyrifos was 0.01–2 μg/ml in blood. The limit of detection and limit of quantification were estimated at 0.002 and 0.01 μg/ml, respectively. The inter- and intra-day precisions, accuracy, and recovery were assessed to verify this method. The results showed that the developed method is rapid, sensitive, and reliable. It is suitable for the determination of chlorpyrifos in forensic toxicological analysis and clinical diagnosis.

  7. Determination of microquantities of methanol and ethanol in toluene by gas chromatography

    International Nuclear Information System (INIS)

    Perez, M. M.

    1970-01-01

    A study is made of the detection of methanol and ethanol in toluene by means of gas chromatography, using Porapak Q columns, 1 m long at 189 degree centigree, employing a flame ionization detector, with propanol as an internal standard. The variation od the detector absolute and relative response was found to be linear within the range of concentration studied, that is, from 5 to 1000 ppm. The limit of sensitivity for the detection of ethanol in a column of 2% Ucon, over Chromosorob G deactivated with 0,1% Carbowax 400, was 20 ppm, which was four times higher than the limit of sensitivity of the Porapak Q column. Also in this case, the absolute and relative response of the detector was linear. (Author) 3 refs

  8. Determination of long-chain fatty acids in serum by gas chromatography coupled to mass spectrometry

    International Nuclear Information System (INIS)

    Nuevas Paz, Lauro; Camayd Viera, Ivette

    2014-01-01

    The quantification of long-chain fatty acids is fundamental for the diagnosis of several peroxisome disorders, particularly those in which the β-oxidation peroxisome of fatty acids is affected. In this work the implementation of an analytical method for the determination of these markers in serum by gas chromatography coupled to mass spectrometry is described. Besides, samples from patients with a diagnostic impression of adrenoleukodystrophy linked to the X chromosome were analyzed. The necessary experimental conditions were achieved for the separation and quantification of C22:0, C24:0 and C26:0 fatty acids in serum, which are biochemical markers of various peroxisome diseases. The application of this method allowed confirming the diagnosis of three patients with a diagnostic impression of adrenoleukodystrophy linked to the X chromosome. The application of the method in daily practice will allow the Cuban medical system to count on a new laboratory parameter for the diagnosis of peroxisome disorders

  9. Thermal and Hydrothermal Treatment of Silica Gels as Solid Stationary Phases in Gas Chromatography

    Directory of Open Access Journals (Sweden)

    Ashraf Yehia El-Naggar

    2013-01-01

    Full Text Available Silica gel was prepared and treated thermally and hydrothermally and was characterized as solid stationary phase in gas chromatography. The characteristics have been evaluated in terms of polarity, selectivity, and separation efficiencies. These parameters were used to assess the outer silica surface contributions and the degree of surface deactivation brought about by different treatment techniques. The parent silica elutes the paraffinic hydrocarbons with high efficiency of separation and elutes aromatic hydrocarbons with nearly good separation and has bad separation of alcohols. The calcined silica at 500°C and 1000°C has a pronounced effect on the separation of aromatic hydrocarbons compared with the parent silica and hydrothermal treatment of silica. With respect to alcohols separation, the obtained bad separations using treated and untreated silica reflect the little effect of the thermal and hydrothermal treatment on the silica surface deactivation.

  10. Analysis of the Aging Processes of Writing Ink: Raman Spectroscopy versus Gas Chromatography Aspects

    Directory of Open Access Journals (Sweden)

    Nikolai M. Grechukha

    2017-09-01

    Full Text Available This work is devoted to the extremely popular but poorly developed scientific and forensic problem of the estimation of the actual dates of inscriptions placed on paper and made by ballpoint pens. It is shown that the degradation of writing inks with time may be controlled via Raman spectroscopy and gas chromatography. The time intervals for the implementation of each of these methods were determined using the ratios of the Raman peak intensities as degradation characteristics rather than their absolute values. In turn, this eliminates the effect of the concentration of a dye. The mutual influence of the volatile components and dyes of writing inks was also investigated and the time interval within which such influence is critical was found. According to the obtained results, a new methodological scheme for determining the age of documents, which were created at least 40 months ago, was proposed.

  11. Physicochemical characterization of dilute n-alcohol/biodiesel mixtures by inverse gas chromatography.

    Science.gov (United States)

    Bobbitt, N Scott; King, Jerry W

    2010-12-10

    Inverse gas chromatography (IGC) has been used to determine the physicochemical parameters that characterize solution thermodynamic interactions in biodiesel-n-alcohol solute systems. Such data is of value to chemical engineers and separation scientists in optimizing separation processes to separate alcoholic solutes at low concentrations in soybean oil methyl ester mixtures (biodiesel). The derived activity and Henry's Law coefficient data can be used to rationalize the interaction of four members of an n-alcoholic homologous series and the soya-based methyl ester solvent in terms of such esters as "green" renewable solvents. Sorption isotherm data confirm linear behavior in most cases between the solute (alcohol) vapor state concentrations and their uptake into the biodiesel phase. Overall, the experimentally determined activity coefficients agree well with those predicted by solution thermodynamic theories as well as correlative chemical engineering equations. Copyright © 2010 Elsevier B.V. All rights reserved.

  12. Improvements in bis(cyclopentadienyl)magnesium purity as determined with gas chromatography-mass spectroscopy

    Energy Technology Data Exchange (ETDEWEB)

    BARTRAM,MICHAEL E.

    2000-03-08

    Bis(cyclopentadienyl)magnesium (MgCp2) is used commonly as a source for doping nitride materials with magnesium. Increased oxygen incorporation known to accompany the use of MgCp2 makes the purity of this precursor an important consideration in nitride CVD. Gas chromatography-mass spectroscopy (GCMS) methods have now been developed for the identification of volatile impurities in MgCp2. Diethylether, an oxygen containing organic compound (CH{sub 3}CH{sub 2}OCH{sub 2}CH{sub 3}), and additional organic impurities were found in the MgCp2 supplied by three manufacturers. Subsequent refinements in the synthetic processes by these companies have resulted in the availability of MgCp2 free of ether and other organic impurities as determined by GCMS.

  13. Fast methods for screening of trichothecenes in fungal cultures using gas chromatography-tandem mass spectrometry

    DEFF Research Database (Denmark)

    Nielsen, Kristian Fog; Thrane, Ulf

    2001-01-01

    The paper presents a fast method for trichothecene profiling and chemotaxonomic studies in species of Fusarium, Stachybotrys, Trichoderma and Memnoniella. Micro scale extracted crude Fusarium extracts were derivatised using pentafluoropropionic anhydride and analysed by gas chromatography......-acetoxyscirpentriol, nivalenol, fusarenon-X, deoxynivalenol, 15-acetyl- deoxynivalenol and 3-acetyl-deoxynivalenol possible during a 23-min GC run. A slightly modified method could detect trichothecenes produced by Stachybotrys, Memnoniella and Trichoderma, by hydrolysing crude extracts prior to derivatisation...... with heptafluorobuturyl imidazole. All types of derivatised extracts could be reanalysed using negative ion chemical ionisation (NICI) GC-MS for molecular mass determination and verification purposes. A retention time index could be used for correction in retention time drifts between sequences and worked both in EI...

  14. Quantification of Selected Vapour-Phase Compounds using Thermal Desorption-Gas Chromatography

    Directory of Open Access Journals (Sweden)

    McLaughlin DWJ

    2014-12-01

    Full Text Available A robust method for the analysis of selected vapour phase (VP compounds in mainstream smoke (MSS is described. Cigarettes are smoked on a rotary smoking machine and the VP that passes through the Cambridge filter pad collected in a TedlarA¯ bag. On completion of smoking, the bag contents are sampled onto an adsorption tube containing a mixed carbon bed. The tube is subsequently analysed on an automated thermal desorption (TD system coupled to a gas chromatography-flame ionization detector (GC-FID using a PoraPLOT-Q column. Quantification of 14 volatile compounds including the major carbonyls is achieved. Details of the method validation data are included in this paper. This method has been used to analyse the VP of cigarette MSS over a wide range of ‘tar’ deliveries and configurations with excellent repeatability. Results for the University of Kentucky reference cigarette 1R4F are in good agreement with reported values.

  15. Fast derivatization of fatty acids in different meat samples for gas chromatography analysis.

    Science.gov (United States)

    Figueiredo, Ingrid Lima; Claus, Thiago; Oliveira Santos Júnior, Oscar; Almeida, Vitor Cinque; Magon, Thiago; Visentainer, Jesuí Vergilio

    2016-07-22

    In order to analyze the composition of fatty acids employing gas chromatography as the separation method, a derivatization of lipids using esterification and transesterification reactions is needed. The methodologies currently available are time consuming and use large amounts of sample and reagents. Thus, this work proposes a new procedure to carry out the derivatization of fatty acids without the need for prior extraction of lipids. The use of small amounts of sample (100mg) allows the analysis to be performed in specific parts of animals, in most cases without having them slaughtered. Another benefit is the use of small amounts of reagents (only 2mL of NaOH/Methanol and H2SO4/Methanol). The use of an experimental design procedure (Design Expert software) allows the optimization of the alkaline and acid reaction times. The procedure was validated for five minutes in both steps. The method was validated for bovine fat, beef, chicken, pork, fish and shrimp meats. The results for the merit figures of accuracy (from 101.07% to 109.18%), precision (RSDintra-day (from 0.65 to 3.93%), RSDinter-day (from 1.57 to 5.22%)), linearity (R(2)=0.9864) and robustness confirmed that the new method is satisfactory within the linear range of 2-30% of lipids in the sample. Besides the benefits of minimizing the amount of samples and reagents, the procedure enables gas chromatography sample preparation in a very short time compared with traditional procedures. Copyright © 2016 Elsevier B.V. All rights reserved.

  16. Measurement of activity coefficients of mixtures by head-space gas chromatography: general procedure.

    Science.gov (United States)

    Luis, Patricia; Wouters, Christine; Van der Bruggen, Bart; Sandler, Stanley I

    2013-08-09

    Head-space gas chromatography (HS-GC) is an applicable method to perform vapor-liquid equilibrium measurements and determine activity coefficients. However, the reproducibility of the data may be conditioned by the experimental procedure concerning to the automated pressure-balanced system. The study developed in this work shows that a minimum volume of liquid in the vial is necessary to ensure the reliability of the activity coefficients since it may become a parameter that influences the magnitude of the peak areas: the helium introduced during the pressurization step may produce significant variations of the results when too small volume of liquid is selected. The minimum volume required should thus be evaluated prior to obtain experimentally the concentration in the vapor phase and the activity coefficients. In this work, the mixture acetonitrile-toluene is taken as example, requiring a sample volume of more than 5mL (about more than 25% of the vial volume). The vapor-liquid equilibrium and activity coefficients of mixtures at different concentrations (0.1, 0.2, 0.3, 0.4, 0.5, 0.6, 0.7, 0.8, 0.9 molar fraction) and four temperatures (35, 45, 55 and 70°C) have been determined. Relative standard deviations (RSD) lower than 5% have been obtained, indicating the good reproducibility of the method when a sample volume larger than 5mL is used. Finally, a general procedure to measure activity coefficients by means of pressure-balanced head-space gas chromatography is proposed. Copyright © 2013 Elsevier B.V. All rights reserved.

  17. [Determination a variety of acidic gas in air of workplace by Ion Chromatography].

    Science.gov (United States)

    Li, Shiyong

    2014-10-01

    To establish a method for determination of a variety of acid gas in the workplace air by Ion Chromatography. (hydrofluoric acid, hydrogen chloride or hydrochloric acid, sulfur anhydride or sulfuric acid, phosphoric acid, oxalic acid). The sample in workplace air was collected by the porous glass plate absorption tube containing 5 ml leacheate. (Sulfuric acid fog, phosphoric acid aerosol microporous membrane after collection, eluted with 5 ml of eluent.) To separated by AS14+AG14 chromatography column, by carbonate (2.0+1.0) mmol/L (Na(2)CO(3)-NaHCO(3)) as eluent, flow rate of 1 ml/min, then analyzed by electrical conductivity detector. The retain time was used for qualitative and the peak area was used for quantitation. The each ion of a variety of acid gas in the air of workplace were excellent in carbonate eluent separation. The linear range of working curve of 0∼20 mg/L. The correlation coefficient r>0.999; lower detection limit of 3.6∼115 µg/L; quantitative limit of 0.012∼0.53 mg/L; acquisition of 15L air were measured, the minimum detection concentration is 0.004 0∼0.13 mg/m(3). The recovery rate is 99.7%∼101.1%. In the sample without mutual interference ions. Samples stored at room temperature for 7 days. The same analysis method, the detection of various acidic gases in the air of workplace, simple operation, good separation effect, high sensitivity, high detection efficiency, easy popularization and application.

  18. Serum/plasma methylmercury determination by isotope dilution gas chromatography-inductively coupled plasma mass spectrometry

    Energy Technology Data Exchange (ETDEWEB)

    Baxter, Douglas C., E-mail: douglas.baxter@alsglobal.com [ALS Scandinavia AB, Aurorum 10, 977 75 Lulea (Sweden); Faarinen, Mikko [ALS Scandinavia AB, Aurorum 10, 977 75 Lulea (Sweden); Osterlund, Helene; Rodushkin, Ilia [ALS Scandinavia AB, Aurorum 10, 977 75 Lulea (Sweden); Division of Geosciences, Lulea University of Technology, 977 87 Lulea (Sweden); Christensen, Morten [ALS Scandinavia AB, Maskinvaegen 2, 183 53 Taeby (Sweden)

    2011-09-09

    Highlights: {center_dot} We determine methylmercury in serum and plasma using isotope dilution calibration. {center_dot} Separation by gas chromatography and detection by inductively coupled plasma mass spectrometry. {center_dot} Data for 50 specimens provides first reference range for methylmercury in serum. {center_dot} Serum samples shown to be stable for 11 months in refrigerator. - Abstract: A method for the determination of methylmercury in plasma and serum samples was developed. The method uses isotope dilution with {sup 198}Hg-labeled methylmercury, extraction into dichloromethane, back-extraction into water, aqueous-phase ethylation, purge and trap collection, thermal desorption, separation by gas chromatography, and mercury isotope specific detection by inductively coupled plasma mass spectrometry. By spiking 2 mL sample with 1.2 ng tracer, measurements in a concentration interval of (0.007-2.9) {mu}g L{sup -1} could be performed with uncertainty amplification factors <2. A limit of quantification of 0.03 {mu}g L{sup -1} was estimated at 10 times the standard deviation of concentrations measured in preparation blanks. Within- and between-run relative standard deviations were <10% at added concentration levels of 0.14 {mu}g L{sup -1}, 0.35 {mu}g L{sup -1} and 2.8 {mu}g L{sup -1}, with recoveries in the range 82-110%. Application of the method to 50 plasma/serum samples yielded a median (mean; range) concentration of methylmercury of 0.081 (0.091; <0.03-0.19) {mu}g L{sup -1}. This is the first time methylmercury has been directly measured in this kind of specimen, and is therefore the first estimate of a reference range.

  19. Determination of residual dimethylsulphoxide in drug loaded gelatin using thermal desorber - gas chromatography.

    Science.gov (United States)

    Asfaw, Adissu Alemayehu; Wolfs, Kris; Van Schepdael, Ann; Adams, Erwin

    2018-05-10

    Traditional headspace - gas chromatography (HS-GC) methods for the determination of residual solvents (RS) start from a homogenous sample solution. Subsequently, it is challenging to determine RS using HS-GC techniques from insoluble solid samples like gelatin which is practically impossible to dissolve or distribute uniformly in water and common organic solvents. In this study, a thermal desorber combined with capillary gas chromatography and flame ionization detection/mass spectrometry (TD-GC-FID/MS) was used for quantitative determination of residual dimethylsulfoxide (DMSO) in gelatin without sample pretreatment. A sample of gelatin was sandwiched between two quartz filter double layers in a polytetrafluoroethylene insert which was then placed in its entirety into a thermal desorption tube. Factors affecting the performance of TD-GC including desorption time, desorption temperature, desorption flow and type of adsorbent were studied by applying a standard solution of DMSO in methanol on a blank gelatin bed. Validation results of the proposed method showed good linearity with an R 2 -value higher than 0.999 for a wide concentration range and good sensitivity with a limit of detection and limit of quantification of 0.1 μg and 0.2 μg on tube, respectively. The proposed method shows recovery values close to 100%. In addition, a conventional HS-GC method following enzymatic degradation of gelatin was developed to verify the proposed TD-GC method. Both methods were applied for the determination of residual DMSO in gelatin that was loaded with an experimental drug. Results were comparable, but the enzyme assisted HS-GC method was more time consuming and expensive. Copyright © 2018 Elsevier B.V. All rights reserved.

  20. An aircraft-borne chemical ionization – ion trap mass spectrometer (CI-ITMS for fast PAN and PPN measurements

    Directory of Open Access Journals (Sweden)

    H. Schlager

    2011-02-01

    Full Text Available An airborne chemical ionization ion trap mass spectrometer instrument (CI-ITMS has been developed for tropospheric and stratospheric fast in-situ measurements of PAN (peroxyacetyl nitrate and PPN (peroxypropionyl nitrate. The first scientific deployment of the FASTPEX instrument (FASTPEX = Fast Measurement of Peroxyacyl nitrates took place in the Arctic during 18 missions aboard the DLR research aircraft Falcon, within the framework of the POLARCAT-GRACE campaign in the summer of 2008. The FASTPEX instrument is described and characteristic properties of the employed ion trap mass spectrometer are discussed. Atmospheric data obtained at altitudes of up to ~12 km are presented, from the boundary layer to the lowermost stratosphere. Data were sampled with a time resolution of 2 s and a 2σ detection limit of 25 pmol mol−1. An isotopically labelled standard was used for a permanent on-line calibration. For this reason the accuracy of the PAN measurements is better than ±10% for mixing ratios greater than 200 pmol mol−1. PAN mixing ratios in the summer Arctic troposphere were in the order of a few hundred pmol mol−1 and generally correlated well with CO. In the Arctic boundary layer and lowermost stratosphere smaller PAN mixing ratios were observed due to a combination of missing local sources of PAN precursor gases and efficient removal processes (thermolysis/photolysis. PPN, the second most abundant PAN homologue, was measured simultaneously. Observed PPN/PAN ratios range between ~0.03 and 0.3.