Identification and quantification of cardiac glycosides in blood and urine samples by HPLC/MS/MS.

Science.gov (United States)

Guan, F; Ishii, A; Seno, H; Watanabe-Suzuki, K; Kumazawa, T; Suzuki, O

1999-09-15

Cardiac glycosides (CG) are of forensic importance because of their toxicity and the fact that very limited methods are available for identification of CG in biological samples. In this study, we have developed an identification and quantification method for digoxin, digitoxin, deslanoside, digoxigenin, and digitoxigenin by high-performance liquid chromatography tandem mass spectrometry (HPLC/MS/MS). CG formed abundant [M + NH4]+ ions and much less abundant [M + H]+ ions as observed with electrospray ionization (ESI) source and ammonium formate buffer. Under mild conditions for collision-induced dissociation (CID), each [M + NH4]+ ion fragmented to produce a dominant daughter ion, which was essential to the sensitive method of selected reaction monitoring (SRM) quantification of CG achieved in this study. SRM was compared with selected ion monitoring (SIM) regarding the effects of sample matrixes on the methodology. SRM produced lower detection limits with biological samples than SIM, while both methods produced equal detection limits with CG standards. On the basis of the HPLC/MS/MS results for CG, we have proposed some generalized points for conducting sensitive SRM measurements, in view of the property of analytes as well as instrumental conditions such as the type of HPLC/MS interface and CID parameters. Analytes of which the molecular ion can produce one abundant daughter ion with high yield under CID conditions may be sensitively measured by SRM. ESI is the most soft ionization source developed so far and can afford formation of the fragile molecular ions that are necessary for sensitive SRM detection. Mild CID conditions such as low collision energy and low pressure of collision gas favor production of an abundant daughter ion that is essential to sensitive SRM detection. This knowledge may provide some guidelines for conducting sensitive SRM measurements of very low concentrations of drugs or toxicants in biological samples.

Screening natural antioxidants in peanut shell using DPPH-HPLC-DAD-TOF/MS methods.

Science.gov (United States)

Qiu, Jiying; Chen, Leilei; Zhu, Qingjun; Wang, Daijie; Wang, Wenliang; Sun, Xin; Liu, Xiaoyong; Du, Fangling

2012-12-15

Peanut shell, a byproduct in oil production, is rich in natural antioxidants. Here, a rapid and efficient method using DPPH-HPLC-DAD-TOF/MS was used for the first time to screen antioxidants in peanut shell. The method is based on the hypothesis that upon reaction with 1, 1-diphenyl-2-picrylhydrazyl (DPPH), the peak areas of compounds with potential antioxidant activities in the HPLC chromatogram will be significantly reduced or disappeared, and the identity confirmation could be achieved by HPLC-DAD-TOF/MS technique. With this method, three compounds possessing potential antioxidant activities were found abundantly in the methanolic extract of peanut shell. They were identified as 5,7-dihydroxychromone, eriodictyol, and luteolin. The contents of these compounds were 0.59, 0.92, and 2.36 mg/g, respectively, and luteolin possessed the strongest radical scavenging capacity. DPPH-HPLC-DAD-TOF/MS assay facilitated rapid identification and determination of natural antioxidants in peanut shell, which may be helpful for value-added utilization of peanut processing byproducts. Copyright © 2012 Elsevier Ltd. All rights reserved.

Determination of blood cyanide by HPLC-MS.

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Tracqui, A; Raul, J S; Géraut, A; Berthelon, L; Ludes, B

2002-04-01

An original high-performance liquid chromatographic-mass spectrometric (HPLC-MS) procedure was developed for the determination of cyanide (CN) in whole blood. After the addition of K13C15N as internal standard, blood was placed in a microdiffusion device, the inner well of which was filled with a mixture of taurine (50mM in water)/naphthalene-2,3-dicarboxaldehyde (NDA, 10mM in methanol)/methanol/ concentrated (approximately 20%) ammonia solution (25:25:45:5, v/v). Concentrated H2SO4 was added to the blood sample, and the microdiffusion chamber was sealed. After 30 min of gentle agitation, 2 microL of the contents of the inner vial were pipetted and directly injected onto a NovaPak C18 HPLC column. Separation was performed by a gradient of acetonitrile in 2mM NH4COOH, pH 3.0 buffer (35-80% in 10 min). Detection was done with a Perkin-Elmer Sciex API-100 mass analyzer with an ionspray interface, operated in the negative ionization mode. MS data were collected as either TIC or SIM at m/z (299 + 191) and (301 + 193) for the derivatives formed with CN and 13C15N, respectively. Inspired by previous works dealing with the complexation of CN by NDA + taurine to form a 1-cyano [f] benzoisoindole derivative analyzed by HPLC-fluorimetry, this method appears simple, rapid, and extremely specific. Limits of detection and quantitation for blood CN are 5 and 15 ng/mL, respectively. The use of 13C15N as internal standard allows the quantitation of CN with elegance and accuracy in comparison with previously reported methods.

HPLC-MS and GC-MS analyses combined with orthogonal partial least squares to identify cytotoxic constituents from turmeric (Curcuma longa L.).

Science.gov (United States)

Jiang, Jianlan; Zhang, Huan; Li, Zidan; Zhang, Xiaohang; Su, Xin; Li, Yan; Qiao, Bin; Yuan, Yingjin

2013-08-01

We investigated the fingerprints of 48 batches of turmeric total extracts (TTE) by HPLC-MS-MS and GC-MS analyses and 43 characteristic peaks (22 constituents from HPLC-MS-MS; 21 from GC-MS) were analyzed qualitatively and quantitatively. An MTT {3-(4,5-dimethylthiazol-2-yl)- 2,5-diphenyltetrazolium bromide} assay was implemented to measure the cytotoxicity of the TTE against HeLa cells. Then we utilized orthogonal partial least squares analysis, which correlated the chemical composition of the TTE to its cytotoxic activity, to identify potential cytotoxic constituents from turmeric. The result showed that 19 constituents contributed significantly to the cytotoxicity. The obtained result was verified by canonical correlation analysis. Comparison with previous reports also indicated some interaction between the curcuminoids and sesquiterpenoids in turmeric.

Determination of anthocyanins from camu-camu (Myrciaria dubia) by HPLC-PDA, HPLC-MS, and NMR.

Science.gov (United States)

Zanatta, Cinthia Fernanda; Cuevas, Elyana; Bobbio, Florinda O; Winterhalter, Peter; Mercadante, Adriana Z

2005-11-30

Camu-camu [Myrciaria dubia (HBK) McVaugh] is a small fruit native to the Amazonian rain forest. Its anthocyanin profile has now been investigated for the first time. Fruits from two different regions of the São Paulo state, Brazil, were analyzed. The major anthocyanins were isolated by high-speed countercurrent chromatography. HPLC-PDA, HPLC-MS/MS, and 1H NMR were used to confirm the identity of the main anthocyanins of camu-camu. Cyanidin-3-glucoside was identified as the major pigment in the fruits from both regions, representing 89.5% in the fruits produced in Iguape and 88.0% in those from Mirandópolis, followed by the delphinidin-3-glucoside, ranging between 4.2 and 5.1%, respectively. Higher total anthocyanin contents were detected in the fruits from Iguape (54.0 +/- 25.9 mg/100 g) compared to those from Mirandópolis (30.3 +/- 6.8 mg/100 g), most likely because of the lower temperatures in the Iguape region.

Quantitative determination of cucurbitane-type triterpenes and triterpene glycosides in dietary supplements containing bitter melon (Momordica charantia) by HPLC-MS/MS.

Science.gov (United States)

Ma, Jun; Krynitsky, Alexander J; Grundel, Erich; Rader, Jeanne I

2012-01-01

Momordica charantia L. (Cucurbitaceae), commonly known as bitter melon, is widely cultivated in many tropical and subtropical areas of the world. It is a common food staple; its fruits, leaves, seeds, stems, and roots also have a long history of use in traditional medicine. In the United States, dietary supplements labeled as containing bitter melon can be purchased over-the-counter and from Internet suppliers. Currently, no quantitative analytical method is available for monitoring the content of cucurbitane-type triterpenes and triterpene glycosides, the major constituents of bitter melon, in such supplements. We investigated the use of HPLC-electrospray ionization (ESI)-MS/MS for the quantitative determination of such compounds in dietary supplements containing bitter melon. Values for each compound obtained from external calibration were compared with those obtained from the method of standard additions to address matrix effects associated with ESI. In addition, the cucurbitane-type triterpene and triterpene glycoside contents of two dietary supplements determined by the HPLC-ESI-MS/MS method with standard additions were compared with those measured by an HPLC method with evaporative light scattering detection, which was recently developed for quantification of such compounds in dried fruits of M. charantia. The contents of five cucurbitane-type triterpenes and triterpene glycosides in 10 dietary supplements were measured using the HPLC-ESI-MS/MS method with standard additions. The total contents of the five compounds ranged from 17 to 3464 microg/serving.

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

International Nuclear Information System (INIS)

Amaral, Priscila Oliveira

2017-01-01

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

HPLC and MS/MS study of polar contaminants in a wetland adjoining a sour-gas plant

International Nuclear Information System (INIS)

Dickson, L.C.; Headley, J.V.; Peru, K.; Spiegel, K.; Gandrass, J.

1995-01-01

An analytical methodology was developed for target analyses and broad spectrum characterization of polar contaminants such as nitrogenous and organosulfur compounds in wetlands using the complementary techniques of HPLC with electrochemical (EC) detection and tandem MS with probe and electrospray ionization. Tandem MS was well suited for the identification and quantification of mixtures of polar compounds in water samples and soil extracts, while HPLC-EC provided sensitive detection of compounds transparent to MS detection and conventional methods. The usefulness of the methodology is demonstrated by studying the removal of polar contaminants from a wetland in western Canada affected by releases of hydrocarbon-rich condensate and free product from an adjoining sour-gas plant. The concern is that the mobile water-soluble polar contaminants may not be as efficiently attenuated by volatilization or adsorption processes as the more hydrophobic hydrocarbons and that some of the polar toxic compounds may break through to contaminate groundwater and surface waters. Samples of groundwater, surface water, and aqueous soil extracts were analyzed to quantify levels of polar contaminants in the presence of high concentrations of hydrocarbons. The use of water extracts reduced the background interference from hydrocarbons and other non-polar compounds that were present in the soil samples. HPLC-EC was used to quantify the target compounds that included monoethanolamine, diethanolamine and methyldiethanolamine and sulfolane-derived compounds while tandem MS was used to identify related compounds and degradation products. Influent concentrations were in the ppm range and discharge concentrations were in the ppb range

Sulphur fertilization influences the sulphur species composition in Allium sativum: sulphomics using HPLC-ICPMS/MS-ESI-MS/MS.

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Raab, Andrea; Ronzan, Marilena; Feldmann, Joerg

2017-10-18

Garlic (A. sativum) contains a large number of small sulphur (S)-containing metabolites, which are important for its taste and smell and vary with A. sativum variety and growth conditions. This study was designed to investigate the influence of different sulphur-fertilization regimes on low molecular weight S-species by attempting the first sulphur mass balance in A. sativum roots and bulbs using HPLC-ICPMS/MS-ESI-MS/MS. Species unspecific quantification of acid soluble S-containing metabolites was achieved using HPLC-ICP-MS/MS. For identification of the compounds, high resolution ESI-MS (Orbitrap LTQ and q-TOF) was used. The plants contained up to 54 separated sulphur-containing compounds, which constitute about 80% of the total sulphur present in A. sativum. The roots and bulbs of A. sativum contained the same compounds, but not necessarily the same amounts and proportions. The S-containing metabolites in the roots reacted more sensitively to manipulations of sulphur fertilization than those compounds in the bulbs. In addition to known compounds (e.g. γ-glutamyl-S-1-propenylcysteine) we were able to identify and partially quantify 31 compounds. Three as yet undescribed S-containing compounds were also identified and quantified for the first time. Putative structures were assigned to the oxidised forms of S-1-propenylmercaptoglutathione, S-2-propenylmercaptoglutathione, S-allyl/propenyl-containing PC-2 and 2-amino-3-[(2-carboxypropyl)sulfanyl]propanoic acid. The parallel use of ICP-MS/MS as a sulphur-specific detector and ESI-MS as a molecular detector simplifies the identification and quantification of sulphur containing metabolites without species specific standards. This non-target analysis approach enables a mass balance approach and identifies the occurrence of the so far unidentified organosulphur compounds. The experiments showed that the sulphur-fertilization regime does not influence sulphur-speciation, but the concentration of some S

HPLC-UV, MALDI-TOF-MS and ESI-MS/MS analysis of the mechlorethamine DNA crosslink at a cytosine-cytosine mismatch pair.

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Pornchai Rojsitthisak

Full Text Available Mechlorethamine [ClCH(2CH(2N(CH(3CH(2CH(2Cl], a nitrogen mustard alkylating agent, has been proven to form a DNA interstrand crosslink at a cytosine-cytosine (C-C mismatch pair using gel electrophoresis. However, the atomic connectivity of this unusual crosslink is unknown.HPLC-UV, MALDI-TOF-MS, and ESI-MS/MS were used to determine the atomic connectivity of the DNA C-C crosslink formed by mechlorethamine, MALDI-TOF-MS of the HPLC-purified reaction product of mechlorethamine with the DNA duplex d[CTCACACCGTGGTTC]•d[GAACCACCGTGTGAG] (underlined bases are a C-C mismatch pair indicated formation of an interstrand crosslink at m/z 9222.088 [M-2H+Na](+. Following enzymatic digestion of the crosslinked duplex by snake venom phosphodiesterase and calf intestinal phosphatase, ESI-MS/MS indicated the presence of dC-mech-dC [mech = CH(2CH(2N(CH(3CH(2CH(2] at m/z 269.2 [M](2+ (expected m/z 269.6, exact mass 539.27 and its hydrolytic product dC-mech-OH at m/z 329.6 [M](+ (expected m/z 329.2. Fragmentation of dC-mech-dC gave product ions at m/z 294.3 and 236.9 [M](+, which are both due to loss of the 4-amino group of cytosine (as ammonia, in addition to dC and dC+HN(CH(3CH = CH(2, respectively. The presence of m/z 269.2 [M](2+ and loss of ammonia exclude crosslink formation at cytosine N(4 or O(2 and indicate crosslinking through cytosine N(3 with formation of two quaternary ammonium ions.Our results provide an important addition to the literature, as the first example of the use of HPLC and MS for analysis of a DNA adduct at the N(3 position of cytosine.

HPLC-ESI-MS/MS analysis of oxidized di-caffeoylquinic acids generated by metalloporphyrin-catalyzed reactions

International Nuclear Information System (INIS)

Santos, Michel D.; Lopes, Norberto P.; Iamamoto, Yassuko

2008-01-01

This paper reports an HPLC-ESI-MS/MS investigation on the oxidation of 3,5- and 4,5- dicaffeoylquinic acid using iron(III) tetraphenylporphyrin chloride as catalyst. Two major mono-oxidised products of the quinic acid moiety have been identified for both compounds. However, only the 4,5-derivative afforded two different tri-oxo products. Thus, it seems that the oxidation pattern depends on the number and positions of the caffeic acid moieties present in caffeoylquinic acid molecules. (author)

HPLC-ESI-MS/MS analysis of oxidized di-caffeoylquinic acids generated by metalloporphyrin-catalyzed reactions

Energy Technology Data Exchange (ETDEWEB)

Santos, Michel D.; Lopes, Norberto P. [Universidade de Sao Paulo (USP), Ribeirao Preto, SP (Brazil). Faculdade de Ciencias Farmaceuticas. Dept. de Fisica e Quimica]. E-mail: npelopes@fcfrp.usp.br; Iamamoto, Yassuko [Universidade de Sao Paulo (USP), Ribeirao Preto, SP (Brazil). Faculdade de Ciencias Farmaceuticas. Dept. de Quimica

2008-07-01

This paper reports an HPLC-ESI-MS/MS investigation on the oxidation of 3,5- and 4,5- dicaffeoylquinic acid using iron(III) tetraphenylporphyrin chloride as catalyst. Two major mono-oxidised products of the quinic acid moiety have been identified for both compounds. However, only the 4,5-derivative afforded two different tri-oxo products. Thus, it seems that the oxidation pattern depends on the number and positions of the caffeic acid moieties present in caffeoylquinic acid molecules. (author)

Rapid HPLC-MS method for the simultaneous determination of tea catechins and folates.

Science.gov (United States)

Araya-Farias, Monica; Gaudreau, Alain; Rozoy, Elodie; Bazinet, Laurent

2014-05-14

An effective and rapid HPLC-MS method for the simultaneous separation of the eight most abundant tea catechins, gallic acid, and caffeine was developed. These compounds were rapidly separated within 9 min by a linear gradient elution using a Zorbax SB-C18 packed with sub 2 μm particles. This methodology did not require preparative and semipreparative HPLC steps. In fact, diluted tea samples can be easily analyzed using HPLC-MS as described in this study. The use of mass spectrometry detection for quantification of catechins ensured a higher specificity of the method. The percent relative standard deviation was generally lower than 4 and 7% for most of the compounds tested in tea drinks and tea extracts, respectively. Furthermore, the method provided excellent resolution for folate determination alone or in combination with catechins. To date, no HPLC method able to discriminate catechins and folates in a quick analysis has been reported in the literature.

HPLC-MS technique for radiopharmaceuticals research and control

International Nuclear Information System (INIS)

Macasek, F.; Bruder, P.; Buriova, E.

2002-01-01

A liquid chromatography/refractive index detector/radiometric detector/ mass spectrometric detector combination (Agilent 1100 HPLC/RAD/DAD/RID/MSD system) is used as a complex technique for quality assessment of radiopharmaceuticals such as 2-deoxy-2-[ 18 F]fluoro-D-glucose (FDG). Optimisation of HPLC/MS analysis was performed investigating the electrospray ionisation (ESI) analytical signal of the mass spectrometer as a function of solvent composition. The anion-exchange eluents applied as specified by the pharmacopoeia are not suitable for ESI detection due to high ion concentrations. Therefore, solutions of glucose in methanol/water and acetonitrile/water solutions of various semi-volatile electrolytes (ammonium chloride, formic acid, ammonium formate) were analysed by flow injection analysis (FIA) and chromatographically. The best analytical response was obtained with acetonitrile : 0.25% ammonium formate = 80:20 solutions. The most intense MSD signals of FDG in ammonium formate were obtained for the following complex ions: (i) positive ions: fdg.NH 4 + , fdg.Na + and (fdg 2 -CH 3 O).Na + (m/z = 200, 205 and 344); (ii) negative ions: fdg.Cl - and fdg.HCOO - (m/z= 217 and 227). The HPLC-MS analysis with Zorbax C-18 and Asahipak-NH2P50 columns gave evidence of admixtures and radiolytic formation of deoxyglucose, deoxychloro-glucose, erythrose, erythritol, gluconic acid, lactose, raffinose, saccharic acid, sorbitol/[ 19 F]FDG, sorbitol/[ 19 F]FDG, xylitol, and other compounds. However, radiometric analysis of expired samples of [ 18 F]FDG gave evidence of a very high radiation stability of its water-ethanol solutions at the point of output of radioactive products. Remarkable is the exceedingly high complexity of the mass spectra of FDG as compared to glucose. Therefore, further research concerns the influence of sodium chloride, linearity of signal response, impurities (mannitol, mannose etc.) interference, and robustness of the MS analysis, with special attention

HPLC-MS technique for radiopharmaceuticals research and control

Energy Technology Data Exchange (ETDEWEB)

Macasek, F; Bruder, P [Department of Nuclear Chemistry, Faculty of Natural Sciences, Comenius University, Bratislava (Slovakia); Buriova, E [Cyclotron Centre of the Slovak Republic, Slovak Office of Standards, Metrology and Testing, Bratislava (Slovakia)

2002-03-01

A liquid chromatography/refractive index detector/radiometric detector/ mass spectrometric detector combination (Agilent 1100 HPLC/RAD/DAD/RID/MSD system) is used as a complex technique for quality assessment of radiopharmaceuticals such as 2-deoxy-2-[{sup 18}F]fluoro-D-glucose (FDG). Optimisation of HPLC/MS analysis was performed investigating the electrospray ionisation (ESI) analytical signal of the mass spectrometer as a function of solvent composition. The anion-exchange eluents applied as specified by the pharmacopoeia are not suitable for ESI detection due to high ion concentrations. Therefore, solutions of glucose in methanol/water and acetonitrile/water solutions of various semi-volatile electrolytes (ammonium chloride, formic acid, ammonium formate) were analysed by flow injection analysis (FIA) and chromatographically. The best analytical response was obtained with acetonitrile : 0.25% ammonium formate = 80:20 solutions. The most intense MSD signals of FDG in ammonium formate were obtained for the following complex ions: (i) positive ions: fdg.NH{sub 4}{sup +}, fdg.Na{sup +} and (fdg{sub 2}-CH{sub 3}O).Na{sup +} (m/z = 200, 205 and 344); (ii) negative ions: fdg.Cl{sup -} and fdg.HCOO{sup -} (m/z= 217 and 227). The HPLC-MS analysis with Zorbax C-18 and Asahipak-NH2P50 columns gave evidence of admixtures and radiolytic formation of deoxyglucose, deoxychloro-glucose, erythrose, erythritol, gluconic acid, lactose, raffinose, saccharic acid, sorbitol/[{sup 19}F]FDG, sorbitol/[{sup 19}F]FDG, xylitol, and other compounds. However, radiometric analysis of expired samples of [{sup 18}F]FDG gave evidence of a very high radiation stability of its water-ethanol solutions at the point of output of radioactive products. Remarkable is the exceedingly high complexity of the mass spectra of FDG as compared to glucose. Therefore, further research concerns the influence of sodium chloride, linearity of signal response, impurities (mannitol, mannose etc.) interference, and

A uHPLC-MS mathematical modeling approach to dry powder inhaler single agglomerate analysis.

Science.gov (United States)

Pennington, Justin; Lena, John; Medendorp, Joseph; Ewing, Gary

2011-10-01

Demonstration of content uniformity (CU) is critical toward the successful development of dry powder inhalers (DPIs). Methods for unit dose CU determination for DPI products are well-established within the field of respiratory science. Recent advances in the area include a uHPLC-MS method for high-throughput uniformity analysis, which allows for a greater understanding of blending operations as the industry transitions to a quality-by-design approach to development. Further enhancements to this uHPLC-MS method now enable it to determine CU and sample weight at the single agglomerate level, which is roughly 50× smaller than a unit dose. When coupled with optical microscopy-based agglomerate sizing, the enhanced uHPLC-MS method can also predict the density and porosity of individual agglomerates. Expanding analytical capabilities to the single agglomerate level provides greater insights and confidence in the DPI manufacturing process.

Analysis of phytochemical variations in dioecious Tinospora cordifolia stems using HPLC/QTOF MS/MS and UPLC/QqQLIT -MS/MS.

Science.gov (United States)

Bajpai, Vikas; Singh, Awantika; Chandra, Preeti; Negi, M P S; Kumar, Nikhil; Kumar, Brijesh

2016-01-01

The stem of dioecious Tinospora cordifolia (Menispermaceae) is a commonly used traditional Ayurvedic medicine in India having several therapeutic properties. To develop and validate LC-MS methods for the identification and simultaneous quantitation of various secondary metabolites and to study metabolomic variations in the stem of male and female plants. Ethanolic extract of stems were analysed by HPLC/ESI-QTOF-MS/MS for rapid screening of bioactive phytochemicals. High resolution MS and MS/MS in positive ESI mode were used for structural investigation of secondary metabolites. An UPLC/ESI-QqQ(LIT) -MS/MS method in MRM mode was developed and validated for the simultaneous quantitation of five bioactive alkaloids. Identification and characterisation of 36 metabolites including alkaloids, sesquiterpenes and phytoecdysteroids were performed using LC-MS and MS/MS techniques. The bioactive alkaloids such as jatrorrhizine, magnoflorine, isocorydine, palmatine and tetrahydropalmatine were successfully quantified in male and female plants. The mean abundances of magnoflorine jatrorrhizine, and oblongine were significantly (P Phytochemicals in the stem of male and female Tinospora cordifolia showed significant qualitative and quantitative variations. LC-MS and MS/MS methods can be used to differentiate between male and female plants based on their chemical profiles and quantities of the marker bioactive alkaloids. This chemical composition difference was also evident during vegetative stage when there were no male and female flowers. Copyright © 2015 John Wiley & Sons, Ltd.

HPLC-ESI-MS/MS analysis of oxidized di-caffeoylquinic acids generated by metalloporphyrin-catalyzed reactions

Directory of Open Access Journals (Sweden)

Michel D. Santos

2008-01-01

Full Text Available This paper reports an HPLC-ESI-MS/MS investigation on the oxidation of 3,5- and 4,5- dicaffeoylquinic acid using iron(III tetraphenylporphyrin chloride as catalyst. Two major mono-oxidised products of the quinic acid moiety have been identified for both compounds. However, only the 4,5-derivative afforded two different tri-oxo products. Thus, it seems that the oxidation pattern depends on the number and positions of the caffeic acid moieties present in caffeoylquinic acid molecules.

Determining the degradation efficiency and mechanisms of ethyl violet using HPLC-PDA-ESI-MS and GC-MS

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Chung Wen-Hsin

2012-06-01

Full Text Available Abstract Background The discharge of wastewater that contains high concentrations of reactive dyes is a well-known problem associated with dyestuff activities. In recent years, semiconductor photocatalysis has become more and more attractive and important since it has a great potential to contribute to such environmental problems. One of the most important aspects of environmental photocatalysis is in the selection of semiconductor materials like ZnO and TiO2, which are close to being two of the ideal photocatalysts in several respects. For example, they are relatively inexpensive, and they provide photo-generated holes with high oxidizing power due to their wide band gap energy. In this work, nanostructural ZnO film on the Zn foil of the Alkaline-Manganese Dioxide-Zinc Cell was fabricated to degrade EV dye. The major innovation of this paper is to obtain the degradation mechanism of ethyl violet dyes resulting from the HPLC-PDA-ESI-MS analyses. Results The fabrication of ZnO nanostructures on zinc foils with a simple solution-based corrosion strategy and the synthesis, characterization, application, and implication of Zn would be reported in this study. Other objectives of this research are to identify the reaction intermediates and to understand the detailed degradation mechanism of EV dye, as model compound of triphenylmethane dye, with active Zn metal, by HPLC-ESI-MS and GC-MS. Conclusions ZnO nanostructure/Zn-foils had an excellent potential for future applications on the photocatalytic degradation of the organic dye in the environmental remediation. The intermediates of the degradation process were separated and characterized by the HPLC-PDA-ESI-MS and GC-MS, and twenty-six intermediates were characterized in this study. Based on the variation of the amount of intermediates, possible degradation pathways for the decolorization of dyes are also proposed and discussed.

Analysis of the extracts of Isatis tinctoria by new analytical approaches of HPLC, MS and NMR.

Science.gov (United States)

Zhou, Jue; Qu, Fan

2011-01-01

The methods of extraction, separation and analysis of alkaloids and indole glucosinolates (GLs) ofIsatis tinctoria were reviewed. Different analytical approaches such as High-pressure Liquid Chromatography (HPLC), Liquid Chromatography with Electrospray Ionization Mass Spectrometry (LC/ESI/MS), Electrospray Ionization Time-Of-Flight Mass Spectrometry (ESI-TOF-MS), and Nuclear Magnetic Resonance (NMR) were used to validate and identity of these constituents. These methods provide rapid separation, identification and quantitative measurements of alkaloids and GLs of Isatis tinctoria. By connection with different detectors to HPLC such as PDA, ELSD, ESI- and APCI-MS in positive and negative ion modes, complicated compounds could be detected with at least two independent detection modes. The molecular formula can be derived in a second step of ESI-TOF-MS data. But for some constituents, UV and MS cannot provide sufficient structure identification. After peak purification, NMR by semi-preparative HPLC can be used as a complementary method.

Automated Liquid Microjunction Surface Sampling-HPLC-MS/MS Analysis of Drugs and Metabolites in Whole-Body Thin Tissue Sections

Energy Technology Data Exchange (ETDEWEB)

Kertesz, Vilmos [ORNL; Van Berkel, Gary J [ORNL

2013-01-01

A fully automated liquid extraction-based surface sampling system utilizing a commercially available autosampler coupled to high performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS) detection is reported. Discrete spots selected for droplet-based sampling and automated sample queue generation for both the autosampler and MS were enabled by using in-house developed software. In addition, co-registration of spatially resolved sampling position and HPLC-MS information to generate heatmaps of compounds monitored for subsequent data analysis was also available in the software. The system was evaluated with whole-body thin tissue sections from propranolol dosed rat. The hands-free operation of the system was demonstrated by creating heatmaps of the parent drug and its hydroxypropranolol glucuronide metabolites with 1 mm resolution in the areas of interest. The sample throughput was approximately 5 min/sample defined by the time needed for chromatographic separation. The spatial distributions of both the drug and its metabolites were consistent with previous studies employing other liquid extraction-based surface sampling methodologies.

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

Science.gov (United States)

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

2017-01-01

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

Proteome profile of functional mitochondria from human skeletal muscle using one-dimensional gel electrophoresis and HPLC-ESI-MS/MS

DEFF Research Database (Denmark)

Lefort, Natalie; Yi, Zhengping; Bowen, Benjamin

2009-01-01

were functional as evidenced by their response to carbohydrate and fat-derived fuels. Using one-dimensional gel electrophoresis and HPLC-ESI-MS/MS, 823 unique proteins were detected, and 487 of these were assigned to the mitochondrion, including the newly characterized SIRT5, MitoNEET and RDH13...

Analysis of brominated and phosphate-based flame retardants in polymer samples by HPLC-UV/MS and online-GPC-HPLC-UV

Energy Technology Data Exchange (ETDEWEB)

Schlummer, M.; Brandl, F. [Fraunhofer-Institut fuer Verfahrenstechnik und Verpackung (IVV), Freising (Germany); Maeurer, A.

2004-09-15

Here we present two analytical approaches for the identification and quantification of brominated and phosphate-based flame retardants. The first is an HPLC-UV/MS approach, which allows the separation and unequivocal identification and quantification of at least 15 different technical flame retardants. The second approach was set-up as a screening tool, consisting of a GPC separation coupled to an HPLC-UV device.

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

Science.gov (United States)

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

2008-01-01

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

[Separation and identification of red pigments in natural red yolk of duck's eggs by HPLC-MS-MS].

Science.gov (United States)

Liu, Liangzhong; Zhang, Min; Peng, Guanghua; Wang, Haibin; Zhang, Shenghua

2004-05-01

The natural red yolk of duck's eggs is produced by the laying duck in the lake areas in southward of China. In the laying duck breeding areas such as Honghu, Jianli, Xiantao, Tianmen and Hanchuan citys in Hubei Province, the culturists are used to feeding fresh pondweeds to the laying ducks. The yolk of duck's eggs is natural red with the chrominance reaching up to and/or above RCF (Roche Yolk Color Fan) 15. The red pigment components of natural red yolk of duck's eggs were separated and identified by thin layer chromatography (TLC), high performance liquid chromatography-mass spectrometry-mass spectrometry (HPLC-MS-MS) and high resolution electron impact-mass spectrometry (EI-MS). Four isomers of red pigments were separated by HPLC on a RP-C18 column with methanol-water (99.5:0.5, v/v) as mobile phase. The lambda(max) of the four components were 482, 488, 496, 501 nm, respectively, and all of them were single peak on chromatogram. They had the same molecular mass (Mr = 562), and had the same fragment peaks of MS2 with rhodoxanthin. The molecular formula of red pigments was determined as C40H50O2 by high resolution EI-MS. The results indicate that the red pigment is rhodoxanthin, and they are all cis-isomers of rhodoxanthin.

Simultaneous quantification of major cannabinoids and metabolites in human urine and plasma by HPLC-MS/MS and enzyme-alkaline hydrolysis

NARCIS (Netherlands)

Aizpurua-Olaizola, Oier; Zarandona, Iratxe; Ortiz, Laura; Navarro, Patricia; Etxebarria, Nestor; Usobiaga, Aresatz

A high performance liquid chromatography coupled to tandem mass spectrometry (HPLC-MS/MS) method for simultaneous quantification of Δ9-tetrahydrocannabinol (THC), its two metabolites 11-hydroxy-Δ9-tetrahydrocannabinol (11-OH-THC) and 11-nor-9-carboxy-Δ9-tetrahydrocannabinol (THC-COOH), and four

Tandem solid-phase extraction followed by HPLC-ESI/QTOF/MS/MS for rapid screening and structural identification of trace diterpenoids in flowers of Rhododendron molle.

Science.gov (United States)

Zou, Hong-Yan; Luo, Jun; Xu, De-Ran; Kong, Ling-Yi

2014-01-01

'Naoyanghua', composed of the flowers of Rhododendron molle G. Don, is a traditional Chinese medicine that is widely known for its toxicity. Grayanane-type diterpenoids are the main active ingredients in R. molle, as well as possibly their toxicity: they are, however, difficult to isolate and analyse using common chromatographic methods, due to their small amounts and absence of conjugated groups, such as phenyl and α, β-unsaturated ketone. To establish a highly sensitive, selective and reliable method for the qualitative evaluation of trace diterpenoids in the flowers of R. molle by using tandem solid-phase extraction followed by high-performance liquid chromatography with electrospray ionisation quadrupole-time-of-flight mass spectrometry (HPLC-ESI/QTOF/MS/MS). Tandem solid phase extraction (SPE) was undertaken using a polyamide cartridge and a C18E cartridge in succession to enrich the trace diterpenoids. HPLC-ESI/QTOF/MS/MS was used to determine the fragmentation patterns of diterpenoids and to tentatively characterise their fragmentation pathways. HPLC-ESI/QTOF/MS/MS detected a total of 14 diterpenoids, eight of which were identified by comparison with literature sources and six based on fragmentation analysis. Among the latter six, rhodojaponin VI-3-glucoside was tentatively identified as a new diterpenoid glycoside and rhodojaponin VII, rhodojaponin IV and rhodojaponin I were reported from R. molle for the first time. By qualitative research of diterpenoids in this plant by HPLC-ESI/QTOF/MS/MS, a reliable methodology for the analysis of these active constituents of R. molle was established for the first time. Copyright © 2014 John Wiley & Sons, Ltd.

HPLC-MS/MS measurement of radiation and photo-induced damage in cellular DNA and human skin

International Nuclear Information System (INIS)

Cadet, Jean; Douki, Thierry; Ravanat, Jean-Luc

2010-01-01

photoproducts including cyclobutane pyrimidine dimers, pyrimidine (6-4) pyrimidone lesions and their Dewar valence isomers that are involved in the etiology of skin cancers. HPLC-MS/MS has been also shown to be an appropriate tool to monitor the formation of the above dimeric photoproducts at the four possible bipyrimidine sites in the DNA of isolated cells and from biopsies of human skin explants upon exposure to UVB radiation. The repair kinetic of each photoproduct has been assessed in cells and human skin by HPLC-MS/MS showing differences between the dimeric lesions. (author)

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

Science.gov (United States)

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

2018-01-01

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

Detection of mono- and di-hexoses as metabolites of 4-bromoaniline using HPLC-TOF-MS/MS.

Science.gov (United States)

Major, H; Castro-Perez, J; Nicholson, J K; Wilson, I D

2003-08-01

1. The metabolic fate of 4-bromoaniline (4-BrA) was investigated in rat following intraperitoneal administration at 50 mg kg(-1) using HPLC-TOF-MS/MS. 2. The sensitivity provided by the use of TOF-MS/MS, aided by the distinctive isotope pattern resulting from the presence of the bromine substituent in the molecule, enabled the detection of many previously uncharacterized metabolites in the samples. 3. Several groups of minor metabolites were detected in the urine that corresponded to a number of isomeric hexose and di-hexose-containing conjugates (possibly glucosides and diglucosides) of 4-BrA. 4. As well as hexose and di-hexose conjugates of 4-BrA, several further groups of metabolites that also contained either a sulphamate or sulphate group in addition to the sugar moieties were also detected.

Chemical characterization of Azadirachta indica grafted on Melia azedarach and analyses of azadirachtin by HPLC-MS-MS (SRM) and meliatoxins by MALDI-MS.

Science.gov (United States)

Forim, Moacir Rossi; Cornélio, Vivian Estevam; da Silva, M Fátima das G F; Rodrigues-Filho, Edson; Fernandes, João B; Vieira, Paulo C; Matinez, Sueli Souza; Napolitano, Michael P; Yost, Richard A

2010-01-01

Melia azedarach adapted to cool climates was selected as rootstocks for vegetative propagation of Azadirachta indica. Cleft grafting of A. indica on M. azedarach rootstock showed excellent survival. Little is known about the chemistry of grafting. The roots, stems, leaves and seeds of this graft were examined in order to verify if grafted A. indica would produce limonoids different from those found in non-grafted plants. Intact matured fruits were also studied to verify if they were free of meliatoxins. After successive chromatographic separations the extracts afforded several limonoids. HPLC-MS/MS and MALDI-MS were used to develop sensitive methods for detecting azadirachtin on all aerial parts of this graft and meliatoxins in fruits, respectively. The stem afforded the limonoid salannin, which was previously found in the oil seeds of A. indica. Salannin is also found in the root bark of M. azedarach. Thus, the finding of salannin in this study suggests that it could have been translocated from the M. azedarach rootstock to the A. indica graft. HPLC-MS/MS analyses showed that azadirachtin was present in all parts of the fruits, stem, flowers and root, but absent in the leaves. The results of MALDI-MS analyses confirmed the absence of meliatoxins in graft fruits. This study showed that A. indica grafted onto M. azedarach rootstock produces azadirachtin, and also that its fruits are free of meliatoxins from rootstocks, confirming that this graft forms an excellent basis for breeding vigorous Neem trees in cooler regions.

HPLC-MS technique in radiopharmaceutical research (the quality control of 18F-2-fluorodeoxyglucose as an example)

International Nuclear Information System (INIS)

Macasek, F.

2001-01-01

Application of radiopharmaceuticals puts increasing demands on their quality control, considering the short half-times, high specific activities (auto-radiolytic effects), and general quality (chemical purity, apyrogenity and sterility) of pharmacy. Mostly, the radioanalytical control consists of application of several separation and instrumental analytical techniques. In this paper, perspective of the hyphenated HPLC and MS techniques is demonstrated on the example of one of the most spread radiopharmaceutical, 2-[ 18 F]fluoro-2-deoxy-D-glucose (further as FDG). In this work, a liquid chromatography/refractive index detector/radiometric detector/mass spectrometric detector combination (HPLC/RID/RAD/MSD) was used for development of a complex routine technique. Optimization of HPLC/MS analysis was performed investigating the electrospray ionization (ESI) analytical signal of mass spectrometer as a function of various eluent composition (see this book, p. 39). Some results, illustrating the glucose and FDG ESI-MS, and also composition of FDG after autoradiolysis, which were obtained either by a TOF Mariner (Perkin Elmer) mass-spectrometer and Agilent 1100 HPLC-MS equipment with quadrupole MS detector are discussed. They give evidence of admixtures and radiolytic formation of deoxyglucose, deoxychloroglucose, erythrose, erytritol, gluconic acid, lactose, raffinose, saccharic acid, sorbitol/[ 19 F]FDG, xylitol, and also univalent ions of C 6 H 10 O 7 F.H 2 O and C 6 H 12 O 8 compounds. The results indicate that the emerging demands on radiopharmaceuticals quality control can be fulfilled in-time only by the radio-HPLC technique developed by the help of a tandem mass-spectrometric detector. (authors)

Identification and evaluation of radiolysis products of irradiated chloramphenicol by HPLC-MS and HPLC-DAD

Energy Technology Data Exchange (ETDEWEB)

Hong, L; Altorfer, H R [Institute of Pharmaceutical Science, Swiss Federal Institute of Technology (ETH), Zurich (Switzerland); Horni, A; Hesse, M [Institute of Organic Chemistry, University of Zurich, Zurich (Switzerland)

2005-07-01

The radiolysis products of chloramphenicol under {gamma}-radiation sterilization were investigated systematically in the present study. Eight main radiolysis products were identified and quantified by HPLC-MS and HPLC-DAD, including two compounds that have never been reported. The minor radiolysis products were quantified, which shows that they are at the concentration levels below the threshold for identification. Carbon-carbon rupture reaction and oxidation reaction were proposed as the main radiolysis reactions of chloramphenicol powder. The applicability of {gamma}-sterilization for chloramphenicol products was quantitatively evaluated with qualitative and quantitative data and the data were compared to the threshold requirements of international regulations for identification. It was concluded that toxicities of the radiolysis products of chloramphenicol produced by {gamma}-radiation sterilization can be neglected, the radiolysis products are safe for human health from chemical view. (author)

Identification and evaluation of radiolysis products of irradiated chloramphenicol by HPLC-MS and HPLC-DAD

International Nuclear Information System (INIS)

Hong, L.; Altorfer, H.R.; Horni, A.; Hesse, M.

2005-01-01

The radiolysis products of chloramphenicol under γ-radiation sterilization were investigated systematically in the present study. Eight main radiolysis products were identified and quantified by HPLC-MS and HPLC-DAD, including two compounds that have never been reported. The minor radiolysis products were quantified, which shows that they are at the concentration levels below the threshold for identification. Carbon-carbon rupture reaction and oxidation reaction were proposed as the main radiolysis reactions of chloramphenicol powder. The applicability of γ-sterilization for chloramphenicol products was quantitatively evaluated with qualitative and quantitative data and the data were compared to the threshold requirements of international regulations for identification. It was concluded that toxicities of the radiolysis products of chloramphenicol produced by γ-radiation sterilization can be neglected, the radiolysis products are safe for human health from chemical view. (author)

HPLC and LC-MS/MS methods for determination of sodium benzoate and potassium sorbate in food and beverages: performances of local accredited laboratories via proficiency tests in Turkey.

Science.gov (United States)

Gören, Ahmet C; Bilsel, Gökhan; Şimşek, Adnan; Bilsel, Mine; Akçadağ, Fatma; Topal, Kevser; Ozgen, Hasan

2015-05-15

High Performance Liquid Chromatography LC-UV and LC-MS/MS methods were developed and validated for quantitative analyses of sodium benzoate and potassium sorbate in foods and beverages. HPLC-UV and LC-MS/MS methods were compared for quantitative analyses of sodium benzoate and potassium sorbate in a representative ketchup sample. Optimisation of the methods enabled the chromatographic separation of the analytes in less than 4 min. A correlation coefficient of 0.999 was achieved over the measured calibration range for both compounds and methods (HPLC and LC-MS/MS). The uncertainty values of sodium benzoate and potassium sorbate were found as 0.199 and 0.150 mg/L by HPLC and 0.072 and 0.044 mg/L by LC-MS/MS, respectively. Proficiency testing performance of Turkish accredited laboratories between the years 2005 and 2013 was evaluated and reported herein. The aim of the proficiency testing scheme was to evaluate the performance of the laboratories, analysing benzoate and sorbate in tomato ketchup. Copyright © 2014 Elsevier Ltd. All rights reserved.

Characterisation of oligosaccharides in vegetables by HPLC and MALDI-TOF MS

Czech Academy of Sciences Publication Activity Database

Štikarovská, M.; Chmelík, Josef

96(S), - (2002), s. S189-S191 ISSN 0009-2770. [Meeting of Chemistry & Life /2./. Brno, 10.09.2002-11.09.2002] Institutional research plan: CEZ:AV0Z4031919 Keywords : oligosaccharides * HPLC * MALDI-TOF-MS Subject RIV: CB - Analytical Chemistry, Separation Impact factor: 0.336, year: 2002

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

Science.gov (United States)

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

2014-04-01

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

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

Energy Technology Data Exchange (ETDEWEB)

Amaral, Priscila Oliveira

2017-07-01

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

Punica granatum peel extracts: HPLC fractionation and LC MS analysis to quest compounds having activity against multidrug resistant bacteria.

Science.gov (United States)

Khan, Ilyas; Rahman, Hazir; Abd El-Salam, Nasser M; Tawab, Abdul; Hussain, Anwar; Khan, Taj Ali; Khan, Usman Ali; Qasim, Muhammad; Adnan, Muhammad; Azizullah, Azizullah; Murad, Waheed; Jalal, Abdullah; Muhammad, Noor; Ullah, Riaz

2017-05-03

Medicinal plants are rich source of traditional herbal medicine around the globe. Most of the plant's therapeutic properties are due to the presence of secondary bioactive compounds. The present study analyzed the High Pressure Liquid Chromatography (HPLC) fractions of Puncia granatum (peel) extracts (aqueous, chloroform, ethanol and hexane) against multidrug resistant bacterial pathogens (Acinetobacter baumannii, Escherichia coli, Pseudomonas aeruginosa and Staphylococcus aureus). All the fractions having antibacterial activity was processed for bioactive compounds identification using LC MS/MS analysis. Among total HPLC fractions (n = 30), 4 HPLC fractions of P. granatum (peel) showed potential activity against MDR pathogens. Fraction 1 (F1) and fraction 4 (F4) collected from aqueous extract showed maximum activity against P. aeruginosa. Fraction 2 (F2) of hexane showed antibacterial activity against three pathogens, while ethanol F4 exhibited antibacterial activity against A. baumannii. The active fractions were processed for LC MS/MS analysis to identify bioactive compounds. Valoneic acid dilactone (aqueous F1 and F4), Hexoside (ethanol F4) and Coumaric acid (hexane F2) were identified as bioactive compounds in HPLC fractions. Puncia granatum peel extracts HPLC fractions exhibited potential inhibitory activity against MDR bacterial human pathogens. Several bioactive compounds were identified from the HPLC fractions. Further characterization of these compounds may be helpful to conclude it as therapeutic lead molecules against MDR pathogens.

Simultaneous determination of 15 phenolic constituents of Chinese black rice wine by HPLC-MS/MS with SPE.

Science.gov (United States)

Wang, Yutang; Liu, Yuanyuan; Xiao, Chunxia; Liu, Laping; Hao, Miao; Wang, Jianguo; Liu, Xuebo

2014-06-01

This study established a new method for quantitative and qualitative determination of certain components in black rice wine, a traditional Chinese brewed wine. Specifically, we combined solid-phase extraction and high-performance liquid chromatography (HPLC) with triple quadrupole mass spectrometry (MS/MS) to determine 8 phenolic acids, 3 flavonols, and 4 anthocyanins in black rice wine. First, we clean samples with OASIS HLB cartridges and optimized extraction parameters. Next, we performed separation on a SHIM-PACK XR-ODS column (I.D. 3.0 mm × 75 mm, 2.2 μm particle size) with a gradient elution of 50% aqueous acetonitrile (V/V) and water, both containing 0.2% formic acid. We used multiple-reaction monitoring scanning for quantification, with switching electrospray ion source polarity between positive and negative modes in a single chromatographic run. We detected 15 phenolic compounds properly within 38 min under optimized conditions. Limits of detection ranged from 0.008 to 0.030 mg/L, and average recoveries ranged from 60.8 to 103.1% with relative standard deviation ≤8.6%. We validated the method and found it to be sensitive and reliable for quantifying phenolic compounds in rice wine matrices. This study developed a new, reliable HPLC-MS/MS method for simultaneous determination of 15 bioactive components in black rice wine. This method was validated and found to be sensitive and reliable for quantifying phenolic compounds in rice wine. © 2014 Institute of Food Technologists®

Quantification of urea in serum by isotope dilution HPLC/MS

International Nuclear Information System (INIS)

Lee, Hwa Shim; Park, Sang Ryoul

2005-01-01

Urea in blood has been measured as an effective marker for diagnosis of renal function. Urea which is the end-product of nitrogen containing metabolites such as proteins is filtered through glomeruli of kidneys and then excreted as urine. If the renal function is deteriorated, the urea concentration in blood will be increased, from which the healthiness of renal function is judged. In order to improve the confidence of diagnosis results, the results must keep traceability chain to certified reference materials, which was certified by primary reference method. In this study, we proposed Isotope Dilution-Liquid Chromatography/Mass Spectrometry (ID-LC/MS) as a candidate primary method, in which 15 N 2 -urea is used as an internal reference material. The developed method is highly accurate in principle and is convenient as it does not require cumbersome derivatization 0.1 mmol/L ammonium chloride was selected as a mobile phase for HPLC because it provide low interference in MS analysis of relatively low molecular weighted urea. HPLC and MS were connected with an ElectroSpry Ionization(ESI) interface of positive mode, which provided high sensitivity and reproducibility. The developed method was validated with internationally recognized reference materials, and we have obtained satisfactory results in an international ring trial. The expanded uncertainty calculated according to ISO guide was 1.8% at 95% confidence interval. The developed method is being used as a primary reference measurement method such as for certification of serum Certified Reference Materials (CRMs)

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

Energy Technology Data Exchange (ETDEWEB)

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

2005-07-01

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

A Validated, Rapid HPLC-ESI-MS/MS Method for the Determination of Lycopsamine.

Science.gov (United States)

Jedlinszki, Nikoletta; Csupor, Dezső

2015-07-01

The aim of the present work was to develop and validate an HPLC-MS/MS method for the determination of a major pyrrolizidine alkaloid of comfrey (lycopsamine) in aqueous samples as a basis for the development of a method for the determination of absorption of lycopsamine by human skin. A linear calibration curve was established in the range of 1.32-440 ng. The intraday precision during the 3-day validation period ranged between 0.57 and 2.48% while the interday precision was 1.70% and 1.95% for quality control samples. LOD was 0.014 ng and recovery was above 97%. The lycopsamine content of the samples stored for 9 and 25 days at 22 degrees C, 10 degrees C and -25 degrees C did not vary. These results underline the good repeatability and accuracy of our method and allow the analysis of samples with very low lycopsamine content.

Determination of vitamins D2 and D3 in selected food matrices by online high-performance liquid chromatography-gas chromatography-mass spectrometry (HPLC-GC-MS).

Science.gov (United States)

Nestola, Marco; Thellmann, Andrea

2015-01-01

An online normal-phase liquid chromatography-gas chromatography-mass spectrometry (HPLC-GC-MS) method was developed for the determination of vitamins D2 and D3 in selected food matrices. Transfer of the sample from HPLC to GC was realized by large volume on-column injection; detection was performed with a time-of-flight mass spectrometer (TOF-MS). Typical GC problems in the determination of vitamin D such as sample degradation or sensitivity issues, previously reported in the literature, were not observed. Determination of total vitamin D content was done by quantitation of its pyro isomer based on an isotopically labelled internal standard (ISTD). Extracted ion traces of analyte and ISTD showed cross-contribution, but non-linearity of the calibration curve was not determined inside the chosen calibration range by selection of appropriate quantifier ions. Absolute limits of detection (LOD) and quantitation (LOQ) for vitamins D2 and D3 were calculated as approximately 50 and 150 pg, respectively. Repeatability with internal standard correction was below 2 %. Good agreement between quantitative results of an established high-performance liquid chromatography with UV detection (HPLC-UV) method and HPLC-GC-MS was found. Sterol-enriched margarine was subjected to HPLC-GC-MS and HPLC-MS/MS for comparison, because HPLC-UV showed strong matrix interferences. HPLC-GC-MS produced comparable results with less manual sample cleanup. In summary, online hyphenation of HPLC and GC allowed a minimization in manual sample preparation with an increase of sample throughput.

Antioxidant capacity and phenolic compounds of Lonicerae macranthoides by HPLC-DAD-QTOF-MS/MS.

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Hu, Xin; Chen, Lin; Shi, Shuyun; Cai, Ping; Liang, Xuejuan; Zhang, Shuihan

2016-05-30

Lonicerae macranthoides with strong antioxidant activity is commonly used in traditional Chinese medicine and folk tea/beverage. However, detailed information about its antioxidant activity and bioactive compounds is limited. Then at first, we comparatively evaluated total phenolic content (TPC), total flavonoid content (TFC) and antioxidant activities of water extract, petroleum ether, ethyl acetate and n-butanol fractions of L. macranthoides. Ethyl acetate fraction exhibited the highest level of TPC (207.38 mg GAE/g DW), TFC (53.06 mg RE/g DW) and the best DPPH scavenge activity and reducing power. n-Butanol fraction showed the best ABTS(+) and O2(-) scavenging activities. Interestingly, water extract, ethyl acetate and n-butanol fractions showed stronger antioxidant activities than positive control, butylated hydroxytoluene (BHT). After that, thirty-one antioxidant phenolic compounds, including twenty-two phenolic acids and nine flavonoids, were screened by DPPH-HPLC experiment and then identified using HPLC-DAD-QTOF-MS/MS. It is noted that twenty-one compounds (1, 3-4, 6-17, 19, 23, 26, 28-29, and 31), as far as was known, were discovered from L. macranthoide for the first time, and eleven of them (3-4, 10-17, and 23) were reported in Lonicera species for the first time. Results indicated that L. macranthoides could serve as promising source of rich antioxidants in foods, beverages and medicines for health promotion. Copyright © 2016 Elsevier B.V. All rights reserved.

Direct injection analysis of fatty and resin acids in papermaking process waters by HPLC/MS.

Science.gov (United States)

Valto, Piia; Knuutinen, Juha; Alén, Raimo

2011-04-01

A novel HPLC-atmospheric pressure chemical ionization/MS (HPLC-APCI/MS) method was developed for the rapid analysis of selected fatty and resin acids typically present in papermaking process waters. A mixture of palmitic, stearic, oleic, linolenic, and dehydroabietic acids was separated by a commercial HPLC column (a modified stationary C(18) phase) using gradient elution with methanol/0.15% formic acid (pH 2.5) as a mobile phase. The internal standard (myristic acid) method was used to calculate the correlation coefficients and in the quantitation of the results. In the thorough quality parameters measurement, a mixture of these model acids in aqueous media as well as in six different paper machine process waters was quantitatively determined. The measured quality parameters, such as selectivity, linearity, precision, and accuracy, clearly indicated that, compared with traditional gas chromatographic techniques, the simple method developed provided a faster chromatographic analysis with almost real-time monitoring of these acids. Copyright © 2011 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

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

International Nuclear Information System (INIS)

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

2003-01-01

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

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

Science.gov (United States)

Molinelli, Alejandro R; Rose, Charles H

2016-01-01

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

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

Energy Technology Data Exchange (ETDEWEB)

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

2012-04-15

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

Quantitative and qualitative analysis of common peaks in chemical fingerprint of Yuanhu Zhitong tablet by HPLC-DAD–MS/MS

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Dao-Quan Tang

2014-04-01

Full Text Available A quality control (QC strategy for quantitative and qualitative analysis of “common peaks” in chemical fingerprint was proposed to analyze Yuanhu Zhitong tablet (YZT, using high performance liquid chromatography with diode array detector and tandem mass spectrometry (HPLC-DAD–MS/MS. The chromatographic separation was achieved on an Agilent Eclipse plus C18 column with a gradient elution using a mixture of 0.4‰ ammonium acetate aqueous (pH 6.0 adjusted with glacial acetic acid and acetonitrile. In chemical fingerprint, 40 peaks were assigned as the “common peaks”. For quantification of “common peaks”, the detection wavelength was set at 254 nm, 270 nm, 280 nm and 345 nm, respectively. The method was validated and good results were obtained to simultaneously determine 10 analytes (protopine, jatrorrhizine, coptisine, palmatine, berberine, xanthotoxin, bergapten, tetrahydropalmatine, imperatorin and isoimperatorin. For qualification of “common peaks”, 33 compounds including 10 quantitative analytes were identified or tentatively characterized using LC–MS/MS. These results demonstrated that the present approach may be a powerful and useful tool to tackle the complex quality issue of YZT. Keywords: Yuanhu Zhitong tablet, Alkaloids, Coumarins, Quality control, HPLC-DAD–MS/MS

Determination of some psychotropic drugs in serum and saliva samples by HPLC-DAD and HPLC MS.

Science.gov (United States)

Petruczynik, A; Wróblewski, K; Szultka-Młyńska, M; Buszewski, B; Karakuła-Juchnowicz, H; Gajewski, J; Morylowska-Topolska, J; Waksmundzka-Hajnos, M

2016-08-05

A simple, rapid and sensitive HPLC-DAD method has been developed and validated for the simultaneous determination of seven psychotropic drugs (risperidone, citalopram, clozapine,quetiapine, levomepromazine, perazine and aripiprazole) in human serum or saliva samples. The chromatographic analyses were performed on a XSELECT CSH Phenyl-Hexyl column with a mobile phase containing methanol, acetate buffer at pH 3.5 and 0.025mL(-1) diethylamine. The influence of concentration of methanol in injection samples and injection volume on peak symmetry and system efficiency was examined.The full separation of all investigated drugs, good peaks' symmetry and simultaneously high systems efficiency were obtained in applied chromatographic system. The method is suitable for the analysis of investigated drugs in human plasma or saliva for psychiatric patients for control of pharmacotherapy, particularly in combination therapy. HPLC-MS was applied for verification of the presence of drugs and their metabolites in serum and saliva samples from patients. Copyright © 2016 Elsevier B.V. All rights reserved.

HPLC-DAD-MS/MS profiling of phenolics from Securigera securidaca flowers and its anti-hyperglycemic and anti-hyperlipidemic activities

Directory of Open Access Journals (Sweden)

Rana M. Ibrahim

Full Text Available Abstract Securigera securidaca (L. Degen & Döefl., Fabaceae, has been widely used in the Iranian, Indian and Egyptian folk medicine as antidiabetic and anti-hyperlipidemic remedy. Phenolic profiling of the ethanolic extract (90% of the flowers of S. securidaca was performed via HPLC-DAD-MS/MS analysis in the positive and negative ion modes. The total polyphenols and flavonoids in the flowers were determined colorimetrically, and the quantification of their components was carried out using HPLC-UV. Total phenolics and flavonoids estimated as gallic acid and rutin equivalents were 82.39 ± 2.79 mg/g and 48.82 ± 1.95 mg/g of the dried powdered flowers, respectively. HPLC-DAD-MS/MS analysis of the extract allowed the identification of 39 flavonoids and eight phenolic acids. Quantitative analysis of some flavonoids and phenolics (mg/100 g powdered flowers revealed the presence of isoquercetrin (3340 ± 2.1, hesperidin (32.09 ± 2.28, naringin (197.3 ± 30.16, luteolin (10.247 ± 0.594, chlorogenic acid (84.22 ± 2.08, catechin (3.94 ± 0.57 and protocatechuic acid (34.4 ± 0.15, in the extract. Moreover, the acute toxicity, hypoglycemic and hypolipidemic effects of the extract were investigated using alloxan induced diabetes in rats in a dose of 100, 200, and 400 mg/kg bwt. The ethanolic extract was safe up to a dose of 2000 mg/kg. All tested doses of the flower extract showed marked decrease in blood glucose level by 31.78%, 66.41% and 63.8% at 100, 200 and 400 mg/kg bwt, respectively, at p < 0.05. Regarding the anti-hyperlipidemic effect, a dose of 400 mg/kg of the flower extract showed the highest reduction in serum triacylglycerides and total cholesterol levels (68.46% and 51.50%, respectively at p < 0.05. The current study proved the folk use of the flowers of S. securidaca as anti-diabetic and anti-hyperlipidemic agent which could be attributed to its high phenolic content.

First characterisation of flavonoid- and diarylheptanoid-type antioxidant phenolics in Corylus maxima by HPLC-DAD-ESI-MS.

Science.gov (United States)

Riethmüller, Eszter; Tóth, Gergő; Alberti, Ágnes; Végh, Krisztina; Burlini, Ilaria; Könczöl, Árpád; Balogh, György Tibor; Kéry, Ágnes

2015-03-25

Corylus maxima Mill. (Betulaceae) leaves have been used in traditional medicine both internally and externally, nevertheless phytochemical exploration of the plant remains incomplete. In this study, the in vitro antioxidant activity and polyphenolic composition of the ethyl acetate and methanolic extracts of C. maxima leaves and bark are reported for the first time. The radical scavenging activities of the extracts were investigated by the ABTS and DPPH assays. All the extracts of C. maxima possessed notable antioxidant activity. By mean of a HPLC-DAD-ESI-TOF and a HPLC-DAD-ESI-MS/MS method, altogether twenty-two phenolics were tentatively characterised: one flavan derivative (1), seven flavonol derivatives (4, 6, 12, 13, 16, 20 and 21) and fourteen diarylheptanoids (2, 3, 5, 7-11, 14, 15, 17-19 and 22). The amount of the two main flavonoids - myricetin-3-O-rhamnoside (6) and quercetin-3-O-rhamnoside (13) - and two diarylheptanoids - oregonin (3) and hirsutenone (15) - in the extracts were determined by a validated HPLC-ESI-MS/MS method in multiple reaction monitoring (MRM) mode. Our results showed that C. maxima could be considered as a valuable source of pharmacologically important natural products that might contribute to the revaluation of the phytotherapeutical potential of the plant. Copyright © 2014 Elsevier B.V. All rights reserved.

Qualitative and quantitative analysis of flavonoids in Sophora tonkinensis by LC/MS and HPLC.

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He, Chang-Ming; Cheng, Zhi-Hong; Chen, Dao-Feng

2013-11-01

To develop analytical methods for the identification and determination of the flavonoids in Sophora tonkinensis for comprehensive quality evaluation. An HPLC-DAD-ESI-MS method was used for the separation and characterization of the flavonoids in S. tonkinensis, and a liquid chromatographic method was employed to simultaneously determine five major active flavonoids in this crude drug. Seventeen flavonoids were identified, among which, seven were unambiguously identified as trifolirhizin, quercetin, formononetin, macckiain, kurarinone, sophoranone, and sophoranochromene by comparing their retention times, and UV and MS spectra with those of the authentic compounds, and the other ten flavonoids were tentatively identified by comparing their UV and MS/MS spectra with those of literature data. Furthermore, five major active flavonoids, including trifolirhizin, quercetin, maackiain, sophoranone, and sophoranochromene were determined in S. tonkinensis. All calibration curves expressed good linearity (r > 0.999 8) within the test ranges, and the recovery from this method was 96.40%-104.43%. The developed HPLC method was successfully applied to quantitatively determine the five flavonoids in seventeen samples of S. tonkinensis. The developed method rapidly characterized the bioactive flavonoids of S. tonkinensis, and could be readily utilized to enhance the quality assurance approaches for this traditional Chinese medicine. Copyright © 2013 China Pharmaceutical University. Published by Elsevier B.V. All rights reserved.

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

DEFF Research Database (Denmark)

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

2005-01-01

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

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

Science.gov (United States)

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

2017-05-01

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

Comparison of HPLC/MS and MALDI-MS for characterizing triacylglycerols in insects: Specie-specific composition of lipids in fat bodies of bumblebee males

Czech Academy of Sciences Publication Activity Database

Kofroňová, Edita; Cvačka, Josef; Vrkoslav, Vladimír; Hanus, Robert; Jiroš, Pavel; Kindl, Jiří; Hovorka, Oldřich; Valterová, Irena

2009-01-01

Roč. 877, č. 30 (2009), s. 3878-3884 ISSN 1570-0232 R&D Projects: GA ČR GA203/09/0139; GA ČR GA203/09/1446; GA MŠk 2B06007 Institutional research plan: CEZ:AV0Z40550506 Keywords : Bumblebee * fat body * triacylglycerols * HPLC/APCI-MS * MALDI-MS Subject RIV: CC - Organic Chemistry Impact factor: 2.777, year: 2009

Quantitative analysis of the major constituents of St John's wort with HPLC-ESI-MS.

Science.gov (United States)

Chandrasekera, Dhammitha H; Welham, Kevin J; Ashton, David; Middleton, Richard; Heinrich, Michael

2005-12-01

A method was developed to profile the major constituents of St John's wort extracts using high-performance liquid chromatography-electrospray mass spectrometry (HPLC-ESI-MS). The objective was to simultaneously separate, identify and quantify hyperforin, hypericin, pseudohypericin, rutin, hyperoside, isoquercetrin, quercitrin and chlorogenic acid using HPLC-MS. Quantification was performed using an external standardisation method with reference standards. The method consisted of two protocols: one for the analysis of flavonoids and glycosides and the other for the analysis of the more lipophilic hypericins and hyperforin. Both protocols used a reverse phase Luna phenyl hexyl column. The separation of the flavonoids and glycosides was achieved within 35 min and that of the hypericins and hyperforin within 9 min. The linear response range in ESI-MS was established for each compound and all had linear regression coefficient values greater than 0.97. Both protocols proved to be very specific for the constituents analysed. MS analysis showed no other signals within the analyte peaks. The method was robust and applicable to alcoholic tinctures, tablet/capsule extracts in various solvents and herb extracts. The method was applied to evaluate the phytopharmaceutical quality of St John's wort preparations available in the UK in order to test the method and investigate if they contain at least the main constituents and at what concentrations.

Carotenoid composition of jackfruit (Artocarpus heterophyllus), determined by HPLC-PDA-MS/MS.

Science.gov (United States)

de Faria, A F; de Rosso, V V; Mercadante, A Z

2009-06-01

Carotenoids are pigments responsible for the yellow-reddish color of many foods and are related to important functions and physiological actions, preventing several chronic-degenerative diseases. The objective of this study was to confirm the carotenoid composition of jackfruit by high-performance liquid chromatography connected to photodiode array and mass spectrometry detectors (HPLC-PDA-MS/MS). The main carotenoids were all-trans-lutein (24-44%), all-trans-beta-carotene (24-30%), all-trans-neoxanthin (4-19%), 9-cis-neoxanthin (4-9%) and 9-cis-violaxanthin (4-10%). Either qualitative or quantitative differences, mainly related to the lutein proportion, were found among three batches of jackfruit. Since the fruits from batch A showed significantly lower contents for almost all carotenoids, it also had the lowest total carotenoid content (34.1 microg/100 g) and provitamin A value, whereas the total carotenoid ranged from 129.0 to 150.3 microg/100 g in the other batches. The provitamin A values from batches B and C were 3.3 and 4.3 microg RAE/100 g, respectively. The carotenoid composition of jackfruit was successfully determined, where 14 of the 18 identified carotenoids were reported for first time. Differences among batches may be due to genetic and/or agricultural factors.

Metabolite profiling of leek (Allium porrum L) cultivars by (1) H NMR and HPLC-MS.

Science.gov (United States)

Soininen, Tuula H; Jukarainen, Niko; Soininen, Pasi; Auriola, Seppo O K; Julkunen-Tiitto, Riitta; Oleszek, Wieslaw; Stochmal, Anna; Karjalainen, Reijo O; Vepsäläinen, Jouko J

2014-01-01

Leek (Allium ampeloprasum var. porrum) is consumed as a vegetable throughout the world. However, little is known about the metabolites of leek cultivars, especially those with potentially important beneficial properties for human health. We provide new information for the overall metabolite composition of several leek cultivars grown in Europe by using HPLC-MS and (1) H NMR. The use of a novel CTLS/NMR (constrained total-line-shape nuclear magnetic resonance) approach was found to be capable of reliable quantification, even with overlapping metabolite signals in the (1) H NMR of plant metabolites. Additionally, a new application for leek flavonoids was optimised for HPLC-MS. The total concentration of carbohydrates (glucose, fructose, kestose/nystose and sucrose) and nine amino acids varied by fourfold in leek juice from different cultivars, while the total concentrations of four organic acids were similar in all cultivars. All the quantified flavonols were kaempferol derivatives or quercetin derivatives and threefold differences in flavonol concentrations were detected between cultivars. In this study, various phytochemical profiles were determined for several leek cultivars by (1) H NMR spectroscopy with CTLS combined with HPLC-MS. The wide variation in bioactive compounds among commercial leek cultivars offers promising opportunities for breeders to raise the levels of important biochemical compounds in leek breeding lines, and also provides some objective measure for quality assurance for the leek industry. Copyright © 2014 John Wiley & Sons, Ltd.

Advantages of automation in plasma sample preparation prior to HPLC/MS/MS quantification: application to the determination of cilazapril and cilazaprilat in a bioequivalence study.

Science.gov (United States)

Kolocouri, Filomila; Dotsikas, Yannis; Apostolou, Constantinos; Kousoulos, Constantinos; Soumelas, Georgios-Stefanos; Loukas, Yannis L

2011-01-01

An HPLC/MS/MS method characterized by complete automation and high throughput was developed for the determination of cilazapril and its active metabolite cilazaprilat in human plasma. All sample preparation and analysis steps were performed by using 2.2 mL 96 deep-well plates, while robotic liquid handling workstations were utilized for all liquid transfer steps, including liquid-liquid extraction. The whole procedure was very fast compared to a manual procedure with vials and no automation. The method also had a very short chromatographic run time of 1.5 min. Sample analysis was performed by RP-HPLC/MS/MS with positive electrospray ionization using multiple reaction monitoring. The calibration curve was linear in the range of 0.500-300 and 0.250-150 ng/mL for cilazapril and cilazaprilat, respectively. The proposed method was fully validated and proved to be selective, accurate, precise, reproducible, and suitable for the determination of cilazapril and cilazaprilat in human plasma. Therefore, it was applied to a bioequivalence study after per os administration of 2.5 mg tablet formulations of cilazapril.

Stability and oxidation products of hydrolysable tannins in basic conditions detected by HPLC/DAD-ESI/QTOF/MS.

Science.gov (United States)

Tuominen, Anu; Sundman, Terhi

2013-01-01

Hydrolysable tannins occur in plants that are used for food or medicine by humans or herbivores. Basic conditions can alter the structures of tannins, that is, the oxidation of phenolic groups can lead to the formation of toxic quinones. Previously, these labile quinones and other oxidation products have been studied with colorimetric or electron paramagnetic resonance methods, which give limited information about products. To study the stability and oxidation products of hydrolysable tannins in basic conditions using HPLC with a diode-array detector (DAD) combined with electrospray ionisation (ESI) and quadrupole time-of-flight (QTOF) MS. Three galloyl glucoses, four galloyl derivatives with different polyols and three ellagitannins were purified from plants. The incubation reactions of tannins were monitored by HPLC/DAD at five pH values and in reduced oxygen conditions. Reaction products were identified based on UV spectra and mass spectral fragmentation obtained with the high-resolution HPLC/DAD-ESI/QTOF/MS. The use of a base-resistant HPLC column enabled injections without the sample pre-treatment and thus detection of short-lived products. Hydrolysable tannins were unstable in basic conditions and half-lives were mostly less than 10 min at pH 10. Degradation rates were faster at pH 11 but slower at milder pH. The HPLC analyses revealed that various products were formed and identified to be the result of hydrolysis, deprotonation and oxidation. Interestingly, the main hydrolysis product was ellagic acid; it was also formed from galloyl glucoses that do not contain oxidatively coupled galloyl groups in their initial structures. HPLD/DAD-ESI/QTOF/MS was an efficient method for the identification of polyphenol oxidation products and showed how different pH conditions determine the fate of hydrolysable tannins. Copyright © 2013 John Wiley & Sons, Ltd.

Bioavailability of wilforlide A in mice and its concentration determination using an HPLC-APCI-MS/MS method.

Science.gov (United States)

Wang, Zhijun; Yeung, Steven; Chen, Shang; Moatazedi, Yasmin; Chow, Moses S S

2018-07-15

Wilforlide A (WA), an active compound in Tripterygium wilfordii Hook F (TW) which is a traditional Chinese medicine for treatment of autoimmune diseases, is a quality control marker for TW product. At present, the bioavailability/pharmacokinetics of WA is not known. Such information is not only essential to evaluate the relevance of WA as a quality control maker, but also important for future clinical efficacy studies. Therefore, a high-performance liquid chromatography-atmospheric pressure chemical ionization tandem mass spectrometric method (HPLC-APCI-MS/MS) was developed and applied to a bioavailability/pharmacokinetic study of WA. WA and celastrol (the internal standard, IS) were extracted by a liquid-liquid extraction method using methyl tert-butyl ether. Multiple reaction monitoring (MRM) scanning in positive ionization mode was used to monitor the transition of m/z 455.1 to 191.3 for WA and 451.3 to 201.2 for IS. This method was validated and applied to a pharmacokinetic study of WA in mice following intravenous administration (IV, 1.2 mg/kg), intraperitoneal injection (IP, 6 mg/kg) and oral administration (PO, 30 mg/kg). The lower limit of quantification (LLOQ) for WA was 10 ng/ml. The intra- and inter-day precision was found to be within 15.4% while the accuracy within 94.1-115.7% for all the quality control and LLOQ samples. The samples were stable under all the usual storage and experimental conditions. The terminal elimination half-lives were 14.7, 9.1 and 22.7 min following IV, IP and PO dosing, while the absolute bioavailability for IP and PO WA were 9.39% and 0.58% respectively. These results indicated that the HPLC-APCI-MS/MS assay was suitable for the pharmacokinetic study of WA. WA was found poorly absorbed when given orally and therefore it may not be a relevant marker for the oral TW products in the market. Copyright © 2018 Elsevier B.V. All rights reserved.

Quantification of underivatised amino acids on dry blood spot, plasma, and urine by HPLC-ESI-MS/MS.

Science.gov (United States)

Giordano, Giuseppe; Di Gangi, Iole Maria; Gucciardi, Antonina; Naturale, Mauro

2012-01-01

Enzyme deficiencies in amino acid (AA) metabolism affecting the levels of amino acids and their derivatives in physiological fluids may serve as diagnostically significant biomarkers for one or a group of metabolic disorders. Therefore, it is important to monitor a wide range of free amino acids simultaneously and to quantify them. This is time consuming if we use the classical methods and more than ever now that many laboratories have introduced Newborn Screening Programs for the semiquantitative analysis, detection, and quantification of some amino acids needed to be performed in a short time to reduce the rate of false positives.We have modified the stable isotope dilution HPLC-electrospray ionization (ESI)-MS/MS method previously described by Qu et al. (Anal Chem 74: 2034-2040, 2002) for a more rapid, robust, sensitive, and specific detection and quantification of underivatised amino acids. The modified method reduces the time of analysis to 10 min with very good reproducibility of retention times and a better separation of the metabolites and their isomers.The omission of the derivatization step allowed us to achieve some important advantages: fast and simple sample preparation and exclusion of artefacts and interferences. The use of this technique is highly sensitive, specific, and allows monitoring of 40 underivatized amino acids, including the key isomers and quantification of some of them, in order to cover many diagnostically important intermediates of metabolic pathways.We propose this HPLC-ESI-MS/MS method for underivatized amino acids as a support for the Newborn Screening as secondary test using the same dried blood spots for a more accurate and specific examination in case of suspected metabolic diseases. In this way, we avoid plasma collection from the patient as it normally occurs, reducing anxiety for the parents and further costs for analysis.The same method was validated and applied also to plasma and urine samples with good reproducibility

Identification and characterization of phenolics and terpenoids from ethanolic extracts of Phyllanthus species by HPLC-ESI-QTOF-MS/MS

Institute of Scientific and Technical Information of China (English)

Sunil Kumar; Awantika Singh; Brijesh Kumar

2017-01-01

Phyllanthus species plants are a rich source of phenolics and widely used due to their medicinal properties. A liquid chromatography–tandem mass spectrometry (LC–MS/MS) method was developed using high-pressure liquid chromatography coupled with quadrupole time-of-flight tandem mass spectrometry (HPLC-ESI-QTOF-MS/MS) for the identification and characterization of quercetin, kaempferol, ellagic acid and their derivatives in ethanolic extracts of Phyllanthus species. The chromatographic separation was carried out on Thermo Betasil C8 column (250 mm×4.5 mm, 5 μm) using 0.1% formic acid in water and 0.1% formic acid in methanol as the mobile phase. The identification of diagnostic fragment ions and optimization of collision energies were carried out using 21 reference standards. Totally 51 compounds were identified which include 21 compounds identified and characterized unambiguously by comparison with their authentic standards and the remaining 30 were tentatively identified and characterized in ethanolic extracts of P. emblica, P. fraternus, P. amarus and P. niruri.

HPLC-MS Analysis of Chloramphenicol Residues in Milk and Powdered Milk Products

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Bošnir, J.

2007-02-01

Full Text Available Chloramphenicol (CAP is a broad-spectrum antibiotic with bacteriostatic action but also has toxic properties, which is why its presence in food and feed is prohibited in Croatia and the European Union.In the aim of consumer protection it is essential to develop a sensitive analytical method for detection of CAP fractions lower than w = 0.3 µg kg-1. For the efficient control and monitoring of CAP, a rapid, sensitive, and selective method for its identification and quantification, using highperformance liquid chromatography in combination with mass spectrometry LC-MS, has been developed.The cleaning procedure was based on the AOAC official method 993.32. HPLC-MS analysis used the ODS Hypersile column and the water/acetonitrile gradient. Electrospray negative ionization (neg ESI was used before single ion monitoring (SIM detection of three m/z 321, 323 and 325. As additional criteria, the ratio between these masses in real and spiked milk samples was also investigated in accordance with theoretical values of the isotope pattern for 2 chlorine atoms present in the analyte.The detection limit of 0.1 µg kg-1 was achieved. The mean value of recovery was 94 %, the correlation coefficient of the calibration curves calculated for 2 m/z values was higher than 0.99.Fourty samples of milk and milk products were tested with the HPLC-MS method, and obtained results showed that samples had CAP 0.37, 0.29, 0.39 µg kg-1, respectively. All the other analysed samples contained CAP concentrations below the detection limit.

Rapid Screening for α-Glucosidase Inhibitors from Gymnema sylvestre by Affinity Ultrafiltration–HPLC-MS

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Mingquan Guo

2017-04-01

Full Text Available Gymnema sylvestre R. Br. (Asclepiadaceae has been known to posses potential anti-diabetic activity, and the gymnemic acids were reported as the main bioactive components in this plant species. However, the specific components responsible for the hypoglycemic effect still remain unknown. In the present study, the in vitro study revealed that the extract of G. sylvestre exhibited significant inhibitory activity against α-glucosidase with IC50 at 68.70 ± 1.22 μg/mL compared to acarbose (positive control at 59.03 ± 2.30 μg/mL, which further indicated the potential anti-diabetic activity. To this end, a method based on affinity ultrafiltration coupled with liquid chromatography mass spectrometry (UF-HPLC-MS was established to rapidly screen and identify the α-glucosidase inhibitors from G. sylvestre. In this way, 9 compounds with higher enrichment factors (EFs were identified according to their MS/MS spectra. Finally, the structure-activity relationships revealed that glycosylation could decrease the potential antisweet activity of sapogenins, and other components except gymnemic acids in G. sylvestre could also be good α-glucosidase inhibitors due to their synergistic effects. Taken together, the proposed method combing α-glucosidase and UF-HPLC-MS presents high efficiency for rapidly screening and identifying potential inhibitors of α-glucosidase from complex natural products, and could be further explored as a valuable high-throughput screening (HTS platform in the early anti-diabetic drug discovery stage.

Analysis of neem oils by LC-MS and degradation kinetics of azadirachtin-A in a controlled environment. Characterization of degradation products by HPLC-MS-MS.

Science.gov (United States)

Barrek, Sami; Paisse, Olivier; Grenier-Loustalot, Marie-Florence

2004-02-01

Since it was first isolated, the oil extracted from seeds of neem (Azadirachtin indica A juss) has been extensively studied in terms of its efficacy as an insecticide. Several industrial formulations are produced as emulsifiable solutions containing a stated titer of the active ingredient azadirachtin-A (AZ-A). The work reported here is the characterization of a formulation of this insecticide marketed under the name of Neem-azal T/S and kinetic studies of the major active ingredient of this formulation. We initially performed liquid-liquid extraction to isolate the neem oil from other ingredients in the commercial mixture. This was followed by a purification using flash chromatography and semi-preparative chromatography, leading to (13)C NMR identification of structures such as azadirachtin-A, azadirachtin-B, and azadirachtin-H. The neem extract was also characterized by HPLC-MS using two ionization sources, APCI (atmospheric pressure chemical ionization) and ESI (electrospray ionization) in positive and negative ion modes of detection. This led to the identification of other compounds present in the extract-azadirachtin-D, azadirachtin-I, deacetylnimbin, deacetylsalannin, nimbin, and salannin. The comparative study of data gathered by use of the two ionization sources is discussed and shows that the ESI source enables the largest number of structures to be identified. In a second part, kinetic changes in the main product (AZ-A) were studied under precise conditions of pH (2, 4, 6, and 8), temperature (40 to 70 degrees C), and light (UV, dark room and in daylight). This enabled us to determine the degradation kinetics of the product (AZ-A) over time. The activation energy of the molecule (75+/-9 kJ mol(-1)) was determined by examining thermal stability in the range 40 to 70 degrees C. The degradation products of this compound were identified by use of HPLC-MS and HPLC-MS-MS. The results enabled proposal of a chemical degradation reaction route for AZ-A under

Determination of Trace Elements in Uranium by HPLC-ID-ICP-MS: NTNFC Final Report

Energy Technology Data Exchange (ETDEWEB)

Manard, Benjamin Thomas [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Wylie, Ernest Miller II [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Xu, Ning [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Tandon, Lav [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

2017-10-19

This report covers the FY 16 effort for the HPLC-ID-ICP-MS methodology 1) sub-method validation for the group I&II elements, 2) sub-method stood-up and validation for REE, 3) sub-method development for the transition element, and 4) completion of a comprehensive SOP for three families of elements.

Identification and quantification of bio-actives and metabolites in physiological matrices by automated HPLC-MS

NARCIS (Netherlands)

van Platerink, C.J.

2010-01-01

Identification and quantification of bio-actives and metabolites in physiological matrices by automated HPLC-MS > Food plays an important role in human health. Nowadays there is an increasing interest in the health effects of so-calles functional foods, e.g. effects on blood pressure, cholesterol

Discrimination of Polish unifloral honeys using overall PTR-MS and HPLC fingerprints combined with chemometrics

NARCIS (Netherlands)

Kus, P.M.; Ruth, van S.M.

2015-01-01

A total of 62 honey samples of six floral origins (rapeseed, lime, heather, cornflower, buckwheat and black locust) were analysed by means of proton transfer reaction mass spectrometry (PTR-MS) and HPLC-DAD. The data were evaluated by principal component analysis and k-nearest neighbours

NMR, HS-SPME-GC/MS, and HPLC/MSn Analyses of Phytoconstituents and Aroma Profile of Rosmarinus eriocalyx.

Science.gov (United States)

Bendif, Hamdi; Miara, Mohamed Djamel; Peron, Gregorio; Sut, Stefania; Dall'Acqua, Stefano; Flamini, Guido; Maggi, Filippo

2017-10-01

In this work, a comprehensive study on the chemical constituents of the aerial parts of Rosmarinus eriocalyx (Lamiaceae), an aromatic shrub traditionally consumed as a food and herbal remedy in Algeria, is presented. The aroma profile was analysed by headspace solid phase microextraction (HS-SPME) coupled with gas chromatography-mass spectrometry (GC/MS), whereas the crude extract constituents were analyzed by 1 H-NMR and by high performance liquid chromatography coupled with mass spectrometry (HPLC/MS n ). Thirty-nine volatile compounds, most of them being monoterpenes, have been identified, with camphor, camphene, and α-pinene as the most abundant constituents. 1 H-NMR analysis revealed the presence of phenolic compounds and betulinic acid while HPLC/MS n allowed the identification of glycosilated and aglyconic flavonoids as well as phenylpropanoid derivatives. Some of these constituents, namely as betulinic acid, rosmanol, and cirsimaritin were reported for the first time in R. eriocalyx. © 2017 Wiley-VHCA AG, Zurich, Switzerland.

Measurement of O(6)-alkylguanine-DNA alkyltransferase activity in tumour cells using stable isotope dilution HPLC-ESI-MS/MS.

Science.gov (United States)

Sun, Guohui; Zhao, Lijiao; Fan, Tengjiao; Ren, Ting; Zhong, Rugang

2016-10-15

The repair of DNA mediated by O(6)-alkylguanine-DNA alkyltransferase (AGT) provides protection against DNA damage from endogenous or exogenous alkylation of the O(6) position of guanine. However, this repair acts as a double-edged sword in cancer treatment, as it not only protects normal cells from chemotherapy-associated toxicities, but also results in cancer cell resistance to guanine O(6)-alkylating antitumour agents. Thus, AGT plays an important role in predicting the individual susceptibility to guanine O(6)-alkylating carcinogens and chemotherapies. Accordingly, it is necessary to establish a quantitative method for determining AGT activity with high accuracy, sensitivity and practicality. Here, we describe a novel nonradioactive method for measuring AGT activity using stable isotope dilution high-performance liquid chromatography electrospray ionization tandem mass spectrometry (HPLC-ESI-MS/MS). This method is based on the irreversibility of the removal of the O(6)-alkyl group from guanine by AGT and on the high affinity of O(6)-benzylguanine (O(6)-BG) as an AGT substrate. HPLC-ESI-MS/MS was used to measure the AGT activities in cell protein extracts from eight tumour lines, demonstrating that AGT activity was quite variable among different cell lines, ranging from nondetectable to 1021 fmol/mg protein. The experiments performed in intact tumour cells yielded similar results but exhibited slightly higher activities than those observed in cell protein extracts. The accuracy of this method was confirmed by an examination of AGT expression levels using western blotting analysis. To our knowledge, this method is the first mass spectrometry-based AGT activity assay, and will likely provide assistance in the screening of cancer risk or the application of chemotherapies. Copyright © 2016 Elsevier B.V. All rights reserved.

Phenolic Profiling of the South American “Baylahuen” Tea (Haplopappus spp., Asteraceae by HPLC-DAD-ESI-MS

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Guillermo Schmeda-Hirschmann

2015-01-01

Full Text Available The aerial parts of several Haplopappus species (Asteraceae, known under the common name “baylahuen”, are used as herbal teas in Chile and Argentina. In Chile, “baylahuen” comprises H. multifolius, H. taeda, H. baylahuen and H. rigidus. Little is known about the chemical identity of the infusion constituents in spite of widespread consumption. The aim of the present work was the characterization of phenolics occurring in the infusions and methanol extracts of “baylahuen” by HPLC-DAD-ESI-MS. A simple HPLC-DAD-ESI-MS method was developed for the fast identification and differentiation of Haplopappus spp. used as a tea source, based on the phenolics from the tea and methanol extracts. Some 27 phenolics were tentatively identified in the infusions and methanol extract, including 10 caffeoyl quinic and feruloyl quinic acid derivatives and 17 flavonoids. The HPLC patterns of the Haplopappus tea and methanol extract allow a clear differentiation at the species level. The occurrence of hydroxycinnamic acid derivatives and flavonoids can explain the reputed nutraceutical and health beneficial properties of this herbal tea.

High throughput HPLC-ESI(-)-MS/MS methodology for mercapturic acid metabolites of 1,3-butadiene: Biomarkers of exposure and bioactivation.

Science.gov (United States)

Kotapati, Srikanth; Esades, Amanda; Matter, Brock; Le, Chap; Tretyakova, Natalia

2015-11-05

1,3-Butadiene (BD) is an important industrial and environmental carcinogen present in cigarette smoke, automobile exhaust, and urban air. The major urinary metabolites of BD in humans are 2-(N-acetyl-L-cystein-S-yl)-1-hydroxybut-3-ene/1-(N-acetyl-L-cystein-S-yl)-2-hydroxybut-3-ene (MHBMA), 4-(N-acetyl-L-cystein-S-yl)-1,2-dihydroxybutane (DHBMA), and 4-(N-acetyl-L-cystein-S-yl)-1,2,3-trihydroxybutyl mercapturic acid (THBMA), which are formed from the electrophilic metabolites of BD, 3,4-epoxy-1-butene (EB), hydroxymethyl vinyl ketone (HMVK), and 3,4-epoxy-1,2-diol (EBD), respectively. In the present work, a sensitive high-throughput HPLC-ESI(-)-MS/MS method was developed for simultaneous quantification of MHBMA and DHBMA in small volumes of human urine (200 μl). The method employs a 96 well Oasis HLB SPE enrichment step, followed by isotope dilution HPLC-ESI(-)-MS/MS analysis on a triple quadrupole mass spectrometer. The validated method was used to quantify MHBMA and DHBMA in urine of workers from a BD monomer and styrene-butadiene rubber production facility (40 controls and 32 occupationally exposed to BD). Urinary THBMA concentrations were also determined in the same samples. The concentrations of all three BD-mercapturic acids and the metabolic ratio (MHBMA/(MHBMA+DHBMA+THBMA)) were significantly higher in the occupationally exposed group as compared to controls and correlated with BD exposure, with each other, and with BD-hemoglobin biomarkers. This improved high throughput methodology for MHBMA and DHBMA will be useful for future epidemiological studies in smokers and occupationally exposed workers. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

Chemical Differentiation of Dendrobium officinale and Dendrobium devonianum by Using HPLC Fingerprints, HPLC-ESI-MS, and HPTLC Analyses

Science.gov (United States)

Ye, Zi; Dai, Jia-Rong; Zhang, Cheng-Gang; Lu, Ye; Wu, Lei-Lei; Gong, Amy G. W.; Wang, Zheng-Tao

2017-01-01

The stems of Dendrobium officinale Kimura et Migo (Dendrobii Officinalis Caulis) have a high medicinal value as a traditional Chinese medicine (TCM). Because of the limited supply, D. officinale is a high priced TCM, and therefore adulterants are commonly found in the herbal market. The dried stems of a closely related Dendrobium species, Dendrobium devonianum Paxt., are commonly used as the substitute; however, there is no effective method to distinguish the two Dendrobium species. Here, a high performance liquid chromatography (HPLC) method was successfully developed and applied to differentiate D. officinale and D. devonianum by comparing the chromatograms according to the characteristic peaks. A HPLC coupled with electrospray ionization multistage mass spectrometry (HPLC-ESI-MS) method was further applied for structural elucidation of 15 flavonoids, 5 phenolic acids, and 1 lignan in D. officinale. Among these flavonoids, 4 flavonoid C-glycosides were firstly reported in D. officinale, and violanthin and isoviolanthin were identified to be specific for D. officinale compared with D. devonianum. Then, two representative components were used as chemical markers. A rapid and reliable high performance thin layer chromatography (HPTLC) method was applied in distinguishing D. officinale from D. devonianum. The results of this work have demonstrated that these developed analytical methods can be used to discriminate D. officinale and D. devonianum effectively and conveniently. PMID:28769988

Determination of Tinopal CBS-X in rice papers and rice noodles using HPLC with fluorescence detection and LC-MS/MS.

Science.gov (United States)

Ko, Kyung Yuk; Lee, Chae A; Choi, Jae Chon; Kim, Meehye

2014-01-01

To date there have been no reports of methods to determine Tinopal CBS-X. We developed a rapid and simple method to determine the Tinopal CBS-X content in rice noodles and rice papers using HPLC equipped with fluorescence detection. Heating the rice noodles and rice papers to 80°C after adding 75% methanol solution induced the release of Tinopal CBS-X from processed rice products. Tinopal CBS-X was separated using an isocratic mobile phase comprising 50% acetonitrile/water containing 0.4% tetrabutyl ammonium hydrogen sulphate at pH 8.0. The samples suspected to be positive by HPLC analysis were then confirmed by LC-MS/MS analysis. This study also investigated the Tinopal CBS-X content of three rice noodle products and two rice papers. The limits of quantification for rice papers and rice noodles were 1.58 and 1.51 µg kg(-1), respectively, and their correlation curves showed good linearity with r(2) ≥ 0.9997 and ≥ 0.9998, respectively. Moreover, rice papers had recoveries of 70.3-83.3% with precision ranging from 5.0% to 7.9%, whereas rice noodles had slightly lower recoveries of 63.4-78.7% and precisions of 8.5-11.5%. Only one rice noodle product contained Tinopal CBS-X, at around 2.1 mg kg(-1), whereas it was not detected in four other samples. Consequently, Tinopal CBS-X from rice noodles and rice papers can be successfully detected using the developed pre-treatment and ion-pairing HPLC system coupled with fluorescence detection.

Hydrolyzable tannins with the hexahydroxydiphenoyl unit and the m-depsidic link: HPLC-DAD-MS identification and model synthesis.

Science.gov (United States)

Arapitsas, Panagiotis; Menichetti, Stefano; Vincieri, Franco F; Romani, Annalisa

2007-01-10

This study was designed to develop efficient analytical tools for the difficult HPLC-DAD-MS identification of hydrolyzable tannins in natural tissue extracts. Throughout the study of the spectroscopic characteristics of properly synthesized stereodefined standards, it was observed that the UV-vis spectra of compounds with the m-depsidic link showed a characteristic shoulder at 300 nm, consistent with the simple glucogalloyl esters, whereas compounds with the hexahydroxydiphenoyl (HHDP) unit gave a diagnostic fragmentation pattern, caused by a spontaneous lactonization in the mass spectrometer. These observations were confirmed by HPLC-DAD-MS analyses of tannic acid and raspberry extracts, which are rich in hydrolyzable tannins with the m-depsidic link and the HHDP unit, respectively.

Identification of ionic chloroacetanilide-herbicide metabolites in surface water and groundwater by HPLC/MS using negative ion spray

Science.gov (United States)

Ferrer, I.; Thurman, E.M.; Barcelo, D.

1997-01-01

Solid-phase extraction (SPE) was combined with high-performance liquid chromatography/high-flow pneumatically assisted electrospray mass spectrometry (HPLC/ESP/MS) for the trace analysis of oxanilic and sulfonic acids of acetochlor, alachlor, and metolachlor. The isolation procedure separated the chloroacetanilide metabolites from the parent herbicides during the elution from C18 cartridges using ethyl acetate for parent compounds, followed by methanol for the anionic metabolites. The metabolites were separated chromatographically using reversed-phase HPLC and analyzed by negative-ion MS using electrospray ionization in selected ion mode. Quantitation limits were 0.01 ??g/L for both the oxanilic and sulfonic acids based on a 100-mL water sample. This combination of methods represents an important advance in environmental analysis of chloroacetanilide-herbicide metabolites in surface water and groundwater for two reasons. First, anionic chloroacetanilide metabolites are a major class of degradation products that are readily leached to groundwater in agricultural areas. Second, anionic metabolites, which are not able to be analyzed by conventional methods such as liquid extraction and gas chromatography/mass spectrometry, are effectively analyzed by SPE and high-flow pneumatically assisted electrospray mass spectrometry. This paper reports the first HPLC/MS identification of these metabolites in surface water and groundwater.

HPLC-MS/MS investigation of biochemical markers for the disclosure of erythropoietin abuse in sports

Science.gov (United States)

Appolonova, S. A.; Dikunets, M. A.; Rodchenkov, G. M.

2009-04-01

The polypeptide hormone erythropoietin (EPO), which is a forbidden doping drug, was determined by high-performance liquid chromatography combined with tandem mass spectrometry (HPLC-MS/MS). The hypothesis about the influence of EPO on the asymmetric dimethylarginine (ADMA)-dimethylargininedime-thylaminohydrolase (DDAH)-NO-synthase system was verified. Changes in this system can serve as indirect biochemical markers of the presence of the forbidden EPO drug in the organism. In the test group, the concentrations of biochemical markers varied from 10 to 40 μg/ml for ADMA and symmetrical DMA (SDMA) and from 0.5 to 10 μg/ml for arginine and citrulline. A single intravenous administration of r-HuEPO (Epocrin, 2000 ME/day) for two volunteers reliably increased ADMA, SDMA, arginine, and citrulline concentrations to 40-270 μg/ml, 40-240μg/ml, 10-60 μg/ml, and 12-140 μg/ml, respectively, with respect to the reference values. The simultaneous increase in arginine, methylarginines, and citrulline contents could be an indirect marker of EPO abuse. The method is recommended for fast screening analysis.

Jackfruit (Artocarpus heterophyllus Lam.) peel: A better source of antioxidants and a-glucosidase inhibitors than pulp, flake and seed, and phytochemical profile by HPLC-QTOF-MS/MS.

Science.gov (United States)

Zhang, Lu; Tu, Zong-Cai; Xie, Xing; Wang, Hui; Wang, Hao; Wang, Zhen-Xing; Sha, Xiao-Mei; Lu, Yu

2017-11-01

Jackfruit (Artocarpus heterophyllus Lam.) peel is an underutilized by-product in both, the production and processing of jackfruit. This research compared the antioxidant and hypoglycemic potential of jackfruit peel with jackfruit pulp, flake and seed for the first time. The phytochemical profile of peel extract was characterized with HPLC-QTOF-MS/MS. Results revealed that peel extract exhibited the highest total phenolic and total flavonoid content, and the phenolics was 4.65, 4.12 and 4.95 times higher than that of pulp, flake and seed extract, respectively. The strongest DPPH and ABTS + scavenging ability, α-glucosidase inhibition were also found in peel extract, and the α-glucosidase inhibition was about 11.8-fold of that of acarbose. The HPLC-QTOF-MS/MS analysis led to the tentative identification of 53 compounds, prenylflavonoids, hydroxycinnamic acids and glycosides are the predominant bioactive compounds. Above results reveal promising potential of jackfruit peel as a new source of natural antioxidants and hypoglycemic agents. Copyright © 2017 Elsevier Ltd. All rights reserved.

[Determination of triterpenoic acids in fruits of Ziziphus jujuba using HPLC-MS with polymeric ODS column].

Science.gov (United States)

Zhang, Yong; Zhou, An; Xie, Xiao-Mei

2013-03-01

A simple and sensitive method has been developed to simultaneously determine betunilic acid, oleanolic acid and ursolic acid in the fruits of Ziziphus jujuba from different regions by HPLC-MS. This HPLC assay was performed on PAH polymeric C18 bonded stationary phase column with mobile phase contained acetonitrile-water (90: 10) and with negative ESI detection mode. The developed approach was characterized by short time consumption for chromatographic separation, high sensitivity and good reliability so as to meet the requirements for rapid analysis of large-batch fruits of Z. jujuba from different habitats.

Polyphenol screening of pomace from red and white grape varieties (Vitis vinifera L.) by HPLC-DAD-MS/MS.

Science.gov (United States)

Kammerer, Dietmar; Claus, Achim; Carle, Reinhold; Schieber, Andreas

2004-07-14

Phenolic compounds of 14 pomace samples originating from red and white winemaking were characterized by HPLC-MS. Up to 13 anthocyanins, 11 hydroxybenzoic and hydroxycinnamic acids, and 13 catechins and flavonols as well as 2 stilbenes were identified and quantified in the skins and seeds by HPLC-DAD. Large variabilities comprising all individual phenolic compounds were observed, depending on cultivar and vintage. Grape skins proved to be rich sources of anthocyanins, hydroxycinnamic acids, flavanols, and flavonol glycosides, whereas flavanols were mainly present in the seeds. However, besides the lack of anthocyanins in white grape pomace, no principal differences between red and white grape varieties were observed. This is the first study presenting comprehensive data on the contents of individual phenolic compounds comprising all polyphenolic subclasses of grapes including a comparison of several red and white pomaces from nine cultivars. The results obtained in the present study confirm that both skins and seeds of most grape cultivars constitute a promising source of polyphenolics.

Phenolic Profiling of Duchesnea indica Combining Macroporous Resin Chromatography (MRC with HPLC-ESI-MS/MS and ESI-IT-MS

Directory of Open Access Journals (Sweden)

Mingzhi Zhu

2015-12-01

Full Text Available Duchesnea indica (D. indica is an important traditional Chinese medicine, and has long been clinically used to treat cancer in Asian countries. It has been described previously as a rich source of phenolic compounds with a broad array of diversified structures, which are the major active ingredients. However, an accurate and complete phenolic profiling has not been determined yet. In the present work, the total phenolic compounds in crude extracts from D. indica were enriched and fractionated over a macroporous resin column, then identified by HPLC-ESI-MS/MS and ESI-IT-MS (ion trap MS. A total of 27 phenolic compounds were identified in D. indica, of which 21 compounds were identified for the first time. These 27 phenolic compounds encompassing four phenolic groups, including ellagitannins, ellagic acid and ellagic acid glycosides, hydroxybenzoic acid and hydroxycinnamic acid derivatives, and flavonols, were then successfully quantified using peak areas against those of the corresponding standards with good linearity (R2 > 0.998 in the range of the tested concentrations. As a result, the contents of individual phenolic compounds varied from 6.69 mg per 100 g dry weight (DW for ellagic acid to 71.36 mg per 100 g DW for brevifolin carboxylate. Not only did this study provide the first phenolic profiling of D. indica, but both the qualitative identification and the subsequent quantitative analysis of 27 phenolic compounds from D. indica should provide a good basis for future exploration of this valuable medicinal plant.

Determination of bifendate in human plasma by HPLC-MS and bioequivalence on bifendate pills in healthy volunteers.

Science.gov (United States)

Zhou, Lingjie; Gu, Lihua; Wang, Yijian; Liang, Jianying

2006-03-03

A sensitive and specific method for the determination of bifendate in human plasma was developed, based on high-performance liquid chromatography (HPLC)-mass spectrometry (MS). The samples were extracted from plasma with diethyl ether, followed by separation and evaporation after addition of internal standard diazepam. The residue was reconstituted in methanol and injected into the HPLC-MS. Chromatography was performed on an Inertsil ODS column with a mobile phase consisting of methanol-distilled water (70/30, v/v) at a flow rate of 0.3 mL/min. Quantitative analysis was achieved by MS detection, using a mass spectrometer equipped with an electrospray ionization interface (ESI) and operated in selected ion monitoring (SIM) and positive-ionization mode using target ions at m/z 419 for bifendate and m/z 285 for internal standard, respectively. The linearity was confirmed in the concentration range of 2-200 ng/mL in human plasma and the precision of this assay was not more than 6.79% over the entire concentration range. The method was sensitive and repeatable enough to be used in pharmacokinetic and bioavailability studies.

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

Energy Technology Data Exchange (ETDEWEB)

Falk, K.

1999-09-01

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

Analytical Method Details (MS): SE29_MS1 [Metabolonote[Archive

Lifescience Database Archive (English)

Full Text Available SE29_MS1 LC-FT-ICR-MS ESI positive method 1 Agilent1100 HPLC (Agilent), LTQ-FT (The... (100mg) are solved in 300uL 80% methanol solution. 20uL sample is injected into HPLC after 0.2um membrane filter treatment. HPLC

Isolation and identification of arctiin and arctigenin in leaves of burdock (Arctium lappa L.) by polyamide column chromatography in combination with HPLC-ESI/MS.

Science.gov (United States)

Liu, Shiming; Chen, Kaoshan; Schliemann, Willibald; Strack, Dieter

2005-01-01

A simple method involving polyamide column chromatography in combination with HPLC-PAD and HPLC-ESI/MS for isolating and identifying two kinds of lignans, arctiin and arctigenin, in the leaves of burdock (Arctium lappa L.) has been established. After extraction of burdock leaves with 80% methanol, the aqueous phase of crude extracts was partitioned between water and chloroform and the aqueous phase was fractionated on a polyamide glass column. The fraction, eluting with 100% methanol, was concentrated and gave a white precipitate at 4 degrees C from which two main compounds were purified by semi-preparative HPLC. In comparison with the UV and ESI-MS spectra and the HPLC retention time of authentic standards, the compounds were determined to be arctiin and arctigenin. The extraction/separation technique was validated using an internal standard method.

Profiling of adrenocorticotropic hormone and arginine vasopressin in human pituitary gland and tumor thin tissue sections using droplet-based liquid-microjunction surface-sampling-HPLC-ESI-MS-MS.

Science.gov (United States)

Kertesz, Vilmos; Calligaris, David; Feldman, Daniel R; Changelian, Armen; Laws, Edward R; Santagata, Sandro; Agar, Nathalie Y R; Van Berkel, Gary J

2015-08-01

Described here are the results from the profiling of the proteins arginine vasopressin (AVP) and adrenocorticotropic hormone (ACTH) from normal human pituitary gland and pituitary adenoma tissue sections, using a fully automated droplet-based liquid-microjunction surface-sampling-HPLC-ESI-MS-MS system for spatially resolved sampling, HPLC separation, and mass spectrometric detection. Excellent correlation was found between the protein distribution data obtained with this method and data obtained with matrix-assisted laser desorption/ionization (MALDI) chemical imaging analyses of serial sections of the same tissue. The protein distributions correlated with the visible anatomic pattern of the pituitary gland. AVP was most abundant in the posterior pituitary gland region (neurohypophysis), and ATCH was dominant in the anterior pituitary gland region (adenohypophysis). The relative amounts of AVP and ACTH sampled from a series of ACTH-secreting and non-secreting pituitary adenomas correlated with histopathological evaluation. ACTH was readily detected at significantly higher levels in regions of ACTH-secreting adenomas and in normal anterior adenohypophysis compared with non-secreting adenoma and neurohypophysis. AVP was mostly detected in normal neurohypophysis, as expected. This work reveals that a fully automated droplet-based liquid-microjunction surface-sampling system coupled to HPLC-ESI-MS-MS can be readily used for spatially resolved sampling, separation, detection, and semi-quantitation of physiologically-relevant peptide and protein hormones, including AVP and ACTH, directly from human tissue. In addition, the relative simplicity, rapidity, and specificity of this method support the potential of this basic technology, with further advancement, for assisting surgical decision-making. Graphical Abstract Mass spectrometry based profiling of hormones in human pituitary gland and tumor thin tissue sections.

Comparative studies of HPLC-fluorometry and LC/MS method for the determination of N-acetylneuraminic acid as a marker of deteriorated ophthalmic solutions.

Science.gov (United States)

Iwatsuka, Kinya; Yasueda, Shin-ichi; Bando, Eiji; Fujii, Hiroyuki; Terada, Takashi; Okubo, Hiroya; Iwamoto, Hiroki; Kinoshita, Mitsuhiro; Kakehi, Kazuaki

2011-10-01

Methods for determining the deterioration of ophthalmic solutions using both high-performance liquid chromatography (HPLC) with fluorescence detection and liquid chromatography coupled with selected ion monitoring mass spectrometry (LC/MS) are described. The methods are based on the determination of N-acetylneuraminic acid (NeuAc) released by the hydrolysis of foreign bodies that contaminate eye drops during use. The released NeuAc was either labeled with 1,2-diamino-4,5-methylenedioxybenzene (DMB) for fluorometric detection or detected without derivatization by mass spectrometry. The calibration curves for NeuAc showed good linearity between 1.2 ng/mL and 39 ng/mL for fluorometric HPLC and 5.0 ng/mL and 100 ng/mL for LC/MS, respectively. Detection limits for fluorometric HPLC and LC/MS were 0.20 ng/mL and 0.88 ng/mL, respectively. The NeuAc content of some model glycoproteins determined by LC/MS method were 62-78% of those determined by fluorometry. The differences are attributed to matrix effects but the LC/MS method afforded sufficiently high sensitivity that NeuAc in the foreign bodies could be determined in eight of nine test samples. Copyright © 2011 Elsevier B.V. All rights reserved.

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

Directory of Open Access Journals (Sweden)

Heliana F. Martins

2013-01-01

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

Characterization of flavonoids in Millettia nitida var. hirsutissima by HPLC/DAD/ESI-MS n

OpenAIRE

Ye, Min; Yang, Wen-Zhi; Liu, Ke-Di; Qiao, Xue; Li, Bei-Jia; Cheng, Jun; Feng, Jie; Guo, De-An; Zhao, Yu-Ying

2011-01-01

Millettia nitida var. hirsutissima is a Chinese herbal medicine used for the treatment of gynecological diseases. An HPLC/DAD/ESI-MSn method was established for the rapid separation and characterization of bioactive flavonoids in M. nitida var. hirsutissima. A total of 32 flavonoids were detected, of which 14 compounds were unambiguously characterized by comparing their retention time, UV, and MS spectra with those of the reference standards, and the others were tentatively identified based o...

Improvement of Nicotinic Acid and Nicotinamide Analysis in Meats and Meat Products by HPLC and LC-MS/MS with Solid-Phase Extraction.

Science.gov (United States)

Hiki, Asako; Yamajima, Yukiko; Uematsu, Yoko

2016-01-01

A method for nicotinic acid (NA) and nicotinamide (NAA) analysis in meats was developed. NA and NAA were extracted from meats or meat products with metaphosphate aqueous solution. The extract was cleaned up with an Oasis MCX cartridge. The cartridge was washed with 2% acetic acid (v/v) and acetic acid-methanol solution. NA and NAA were eluted with ammonia-methanol solution. NA and NAA in the eluate were chromatographed on a Scherzo SM-C18 (3.0×150 mm, 3.0 μm) column with 20 mmol/L ammonium acetate containing 0.1% acetic acid-acetonitrile (97 : 3) as a mobile phase and were monitored at 261 nm. Quantification was performed by LC and LC-MS/MS. Calibration curves showed high linearity (correlation coefficient>0.998) between 1-25 μg/mL for LC and LC-MS/MS. Recoveries were 84-108% (CV≦5.8%) by HPLC and 79-105% (CV≦9.0%) by LC-MS/MS. The limit of quantitation for NA was 0.005-0.01 g/kg and that for NAA was 0.01-0.02 g/kg.

Identification and Quantification of Alkaloid in KHR98 and Fragmentation Pathways in HPLC-Q-TOF-MS.

Science.gov (United States)

Long, Jiakun; Wang, Yang; Xu, Chen; Liu, Tingting; Duan, Gengli; Yu, Yingjia

2018-05-01

Uncaria rhynchophylla is woody climber plant distributed mainly in China and Japan, the stems and hooks of which can be collected as "Gou-Teng" for the treatment of hyperpyrexia, epilepsy and preeclampsia. Fudan University first manufactured KHR98, the extract of Uncaria rhynchophylla. In order to study the active components and structural information of KHR98, we established a HPLC coupled with quadrupole time-of-flight (Q-TOF)-MS method for rapid analysis of alkaloids. In qualitative analysis, a total of eight compounds, including four known alkaloids and four unknown components, were detected and identified. The fragmentation behaviors, such as the fragment ion information and the fragmentation pathways of the eight components were summarized simultaneously, and the concentration of the above components was determined by HPLC-MS method. The quantitative method was proved to be reproducible, precise and accurate. This study shed light on the standardization and quality control of the KHR98 and provided a foundation for the further research on pharmacology, follow-up clinical research and New Drug Applications.

Qualitative analysis of MDR-reversing Anastasia Black (Russian black sweet pepper, Capsicum annuum, Solanaceae) extracts and fractions by HPLC and LC-MS-MS methods.

Science.gov (United States)

Schelz, Zsuzsanna; Molnár, Joseph; Fogliano, Vincenzo; Ferracane, Rosalia; Pernice, Rita; Shirataki, Yoshiaki; Motohashi, Noboru

2006-01-01

In earlier experiments, the MDR (multidrug resistance)-reversal activities of Anastasia Black (Russian black sweet pepper) extracts had been analysed. Recently, the most effective MDR reversing extracts and fractions have been separated by HPLC (high-performance liquid chromatography, for carotenoids) and LC-MS-MS (HPLC combined with mass spectrometry, for phenolic compounds) methods. As a result of the analytical studies, the following flavonoids had been identified: feruloyl glucopyranoside, quercetin rhamnopyranoside glucopyranoside, luteolin glucopyranoside arabinopyranoside, apigenin glucopyranoside arabinopyranoside, quercetin rhamnopyranoside, luteolin arabinopyranoside diglucopy-ranoside, hesperidine and luteolin glucuronide. According to the literature, the aglycones of these phenolic compounds exhibit MDR-reversal activity in vitro, and the connection between the phenolic content of Anastasia Black and MDR-reversal action was therefore studied by different analytical methods. The results of this study revealed that the identified flavonoids of Anastasia Black may be only partially responsible for the modulation of the MDR of mouse lymphoma cells. Other lipophilic compounds, most probably carotenoids, present in Russian black sweet pepper may act as inhibitors of MDR reversal.

Quantifying fenbendazole and its metabolites in self-medicating wild red grouse Lagopus lagopus scoticus using an HPLC-MS-MS approach.

Science.gov (United States)

Adam, Aileen; Webster, Lucy M I; Mullen, William; Keller, Lukas F; Johnson, Paul C D

2011-05-11

On red grouse estates in the UK the nematode parasite Trichostrongylus tenuis is often controlled by application of grit medicated with the anthelmintic fenbendazole (FBZ). To date, assessment of the efficacy has been inhibited by the inability to quantify uptake of FBZ by the birds. We have developed a simple and sensitive HPLC-MS-MS method for detecting and quantifying FBZ and its metabolites from a 300 mg sample of red grouse liver. This method could be used to improve the efficacy of medicated grit treatment by allowing the identification of conditions and application methods that optimize the uptake of FBZ. With the necessary modifications, our method will also be applicable to other wildlife species where self-medication is used for parasite control. Copyright © 2011 Elsevier B.V. All rights reserved.

HPLC-DAD-MS/MS profiling of antioxidant flavonoid glycosides in sea buckthorn (Hippophae rhamnoides L.) seeds.

Science.gov (United States)

Arimboor, Ranjith; Arumughan, C

2012-09-01

This study was aimed at the chemical profiling of flavonoid glycosides in antioxidant (AO) fractions of sea buckthorn (Hippophae rhamnoides) seed. Seed fractions were evaluated for their DPPH, ABTS, superoxide and hydroxyl radical scavenging, ferric reduction, ferrous chelation and xanthine oxidase inhibitory capacities. HPLC-DAD-ESI-MS/MS analytical conditions for the profiling of seed flavonoids were optimized and the AO-rich fraction was analysed. Quercetin-3-O-rutinoside (5.9%), isorhamnetin-3-O-rutinoside (4.9%) and isorhamnetin-3-O-sophroside-7-O-rhamnoside (3.7%) were found as the major flavonoid glycosides in the fraction. Significant amounts of isorhamnetin-3-O-glucoside (2.8%), 3-O-sophroside-7-O-rhamnosides of quercetin (2.4%) and kaempherol (1.3%), and 3-O-glucoside-7-O-rhamnosides of quercetin (1.1%) and isorhamnetin (1.1%) along with their free forms: isorhamnetin (2.7%), quercetin (1.1%) and kaempherol (0.6%) were also found in the fraction. The identification of flavonoids as the major less polar AO phenolics in the seeds was rationalized by demonstrating the high AO activity of isorhamnetin, quercetin, kaempherol and quercetin-3-O-rutinoside.

Detection of low plasma estradiol concentrations in nesting green turtles (Chelonia mydas) by HPLC/Ms-Ms.

Science.gov (United States)

Mahmoud, I Y; Alkindi, A Y; Khan, T; Al-Bahry, S N

2011-03-01

In previous studies on nesting green turtles under natural conditions from different geographical regions, 17-β-estradiol (E(2) ) was either undetectable or detected at very low levels. RIA and other related techniques were not sensitive enough to measure low E(2) values in the green turtles. In this study, a sensitive method was used in detecting low hormone concentrations: high performance liquid chromatography with tandem quadruple mass spectrometry (HPLC-MS/MS). Using this technique, estradiol for the first time was detected in nesting green turtles during the peak season (June-October) at Ras Al-Hadd Reserve, Oman. The E(2) values recorded from this study were the highest ever recorded from nesting green turtles in any geographical region, but the levels did not vary significantly throughout different phases of nesting. The presence of E(2) during nesting presumably plays a role in the physiology and behavior of this species. Ras Al-Hadd hosts one of the largest nesting populations of green turtles in the world, and an understanding of their nesting patterns may be of value in conservation and management programs for this endangered species. Copyright © 2011 Wiley-Liss, Inc., A Wiley Company.

A comparison of the determination and speciation of inorganic arsenic using general HPLC methodology with UV, MS and MS/MS detection.

Science.gov (United States)

Gilmartin, Gregory; Gingrich, Diane

2018-04-15

The determination and speciation of arsenic in natural resources such as drinking water and agricultural soils has been a growing concern in recent years due to its many toxicological effects [1-3]. To speciate and quantitate concentrations of arsenic, typically an ion chromatograph (IC) interfaced to an inductively coupled plasma mass spectrometer (ICP-MS) is employed [4-9]. This methodology may be very robust and sensitive, but it is expensive and not as ubiquitous as high performance liquid chromatography (HPLC) with ultraviolet (UV) absorbance detection or electrospray ionization mass spectrometry (ESI-MS). Anion exchange chromatography is a well-documented means of speciating arsenite (As(III), As 2 O 3 ) and arsenate (As(V), AsO 4 ) using UV [10], conductivity [11], or ESI-MS detection [12,13]. This paper demonstrates the utilization of common liquid chromatographic instrumentation to speciate and determines inorganic Arsenic compounds using UV or MS via selected ion recording (SIR) or multiple reaction monitoring (MRM) detection. This paper describes the analysis of arsenite and arsenate samples prepared using both deionized and ground water. The limit of quantitation for the techniques described in this paper for samples spiked in ground water were 454 ppb (As(III)) and 562 ppb (As(V)) for UV detection, 45.4 ppb (As(III)) and 56.2 ppb (As(V)) for SIR detection, and 4.54 ppb (As(III)) and 5.62 ppb (As(V)) for MRM detection. Copyright © 2018 Elsevier B.V. All rights reserved.

A novel HPLC-MS/MS method for the simultaneous determination of astemizole and its major metabolite in dog or monkey plasma and application to pharmacokinetics.

Science.gov (United States)

Back, Hyun-moon; Lee, Jong-Hwa; Chae, Jung-woo; Song, Byungjeong; Seo, Joung-Wook; Yun, Hwi-yeol; Kwon, Kwang-il

2015-10-10

Astemizole (AST), a second-generation antihistamine, is metabolized to desmethyl astemizole (DEA), and although it has been removed from the market for inducing QT interval prolongation, it has reemerged as a potential anticancer and antimalarial agent. This report describes a novel high-performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS) method for simultaneously determining the concentrations of AST and DEA in beagle dog and cynomolgus monkey plasma with simple preparation method and short retention time. Prior to HPLC analyses, the plasma samples were extracted with simple liquid-liquid extraction method. The isocratic mobile phase was 0.025% trifluoroacetic acid (TFA dissolved in acetonitrile) and 20 mM ammonium acetate (94:6) at a flow rate of 0.25 mL/min and diphenhydramine used as internal standard. In MS/MS analyses, precursor ions of the analytes were optimized as protonated molecular ions: [M+H](+). The lower limit of quantification of astemizole was 2.5 ng/mL in both species and desmethyl astemizole were 7.5 ng/mL and 10 ng/mL in dog and monkey plasma, respectively. The accuracy, precision, and stability of the method were in accordance with FDA guidelines for the validation of bioanalytical methods. Finally this validated method was successfully applied to a pharmacokinetic study in dogs and monkeys after oral administration of 10 mg/kg AST. Copyright © 2015 Elsevier B.V. All rights reserved.

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

DEFF Research Database (Denmark)

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

2005-01-01

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

HPLC/DAD-MS CHARACTERISATION OF DIVERSE DYESTUFFS FROM A CASE STUDY OF HISTORIC FABRIC

OpenAIRE

Wafaa, Mohamed; Mai, Rifai; Fatmaa El Zahraa, Sadat; Turkan, Yurdun

2017-01-01

Unknown dyestuffs from a red crimson coloured historic fabric are analysed with both High Performance Liquid Chromatography (HPLC) coupled with Diode Array Detection (DAD) and Liquid Chromotography coupled with Mass Spectrometry(LC-MS.)The dyed fabric dates back to 18th -19th centuries AD and is located in the National Museum of Beit El Omma in Egypt. the lengthwise and crosswise yarns have different colours, thus different dyes are anticipated. Chromatographic separation of the hydrolysed sa...

RP-HPLC/MS-APCI Analysis of Branched Chain TAG Prepared by Precursor-Directed Biosynthesis with Rhodococcus erythropolis

Czech Academy of Sciences Publication Activity Database

Schreiberová, O.; Krulikovská, T.; Sigler, Karel; Čejková, A.; Řezanka, Tomáš

2010-01-01

Roč. 45, č. 8 (2010), s. 743-756 ISSN 0024-4201 R&D Projects: GA MŠk 2B08062 Institutional research plan: CEZ:AV0Z50200510 Keywords : Rhodococcus erythropolis * RP-HPLC/MS-APCI * Branched chain triacylglycerols Subject RIV: EE - Microbiology, Virology Impact factor: 2.151, year: 2010

Preparation and determination of desethylamiodarone in dog lung by HPLC-MS.

Science.gov (United States)

Hong, Liu Xue; Ying, Yang Chuan; Lei, Zheng; Chen, Guo Rui

2011-11-01

A novel method was developed for the preparation and determination of desethylamiodarone in dog lung by high-performance liquid chromatography (HPLC) with amiodarone as a standard. The selected dog was orally given amiodarone, then executed and the active metabolite desethylamiodirone in lung tissue was isolated, concentrated and purified by Waters C18 column (25 mm x 250 mm, 10 microm) with mobile phase of acetonitrile-100 mmol/L acetic acid containing 15 mmol/L diethylamine (55:45 v/v) at a flow rate of 10.0 mL/min. Hypersil ODS2 column (4.6 mm x 250 mm 5 microm) was used to analyze amiodarone and desethylamiodarone, with the same mobile phase at a flow rate of 1.0 mL/min, the detection wavelength was 237.5 nm. Atmosperic pressure electronic spray ionization (AP-ESI) and ion mass spectral (m/z) of 618.1(M + H) were selected to validate desethylamiodarone. The f(i) of desethylamiodarone and amiodarone were 1.04 +/- 0.02 and 1.020 +/- 0.01, respectively. It indicated that desethylamiodarone can be separated and purified by preparational HPLC after Mass Spectrometry (MS) validation and quantified according to f(i) of amiodarone indirectly. The proposed method enables the preparation and determination of desethylamiodarone in dog lung successfully.

Structural investigations of flavonol glycosides from sea buckthorn (Hippophaë rhamnoides) pomace by NMR spectroscopy and HPLC-ESI-MS(n).

Science.gov (United States)

Rösch, Daniel; Krumbein, Angelika; Mügge, Clemens; Kroh, Lothar W

2004-06-30

Four flavonol glycosides were isolated from an extract of sea buckthorn pomace (Hippophaë rhamnoides) by Sephadex LH-20 gel chromatography and semipreparative HPLC. Their structures were elucidated by hydrolysis studies, ESI-MS(n), UV, and (1)H and (13)C NMR spectroscopy. The occurrence of the major flavonol glycoside kaempferol 3-O-beta-sophoroside-7-O-alpha-rhamnoside in sea buckthorn is described here for the first time. A further 21 flavonol glycosides of Sephadex LH-20 fractions of sea buckthorn pomace were characterized by HPLC-DAD-ESI-MS. The characteristic MS-MS and MS(3) fragmentation pattern of flavonol glycosides previously identified in sea buckthorn juice and of flavonol glycosides identified by NMR spectroscopy gave valuable indications for their identification. The results demonstrate that loss of the sugar moiety from C-7 of the aglycon is more favored than fission of the glycosidic linkage at the C-3 position. Thus, most of the compounds identified were 7-rhamnosides of isorhamnetin, kaempferol, and quercetin, which exhibit different substitution patterns at the C-3 position, mainly glucosides, rutinosides, and sophorosides. In addition, numerous flavonol glycosides were detected lacking a sugar moiety at C-7. Finally, eight flavonol derivatives were identified that are acylated by hydroxybenzoic or hydoxycinnamic acids.

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

International Nuclear Information System (INIS)

Suzuki, K.T.

1996-01-01

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

Fragmentation patterns involving ammonium adduct fragment ions: A comparison of the determination of metaldehyde in human blood by HPLC-QqQ-MS/MS and UHPLC-Q-TOF-MS.

Science.gov (United States)

Szpot, Paweł; Buszewicz, Grzegorz; Jurek, Tomasz; Teresiński, Grzegorz

2018-05-15

This paper presents a rapid, sensitive and precise method for the determination of metaldehyde in human blood, using ultra-performance liquid chromatography coupled with quadrupole time-of-flight tandem mass spectrometry and high-performance liquid chromatography coupled with triple quadrupole tandem mass spectrometry. Separation was performed with a Poroshell 120 EC-C18 column; 2.7 μm atrazine‑d5 (IS) and 200 mg NaCl were added to the blood sample. Proteins in human blood were precipitated using acetonitrile; the supernatant was then analyzed with the UHPLC-Q-TOF-MS or HPLC-QqQ-MS/MS system. The results of selectivity, linearity, accuracy, precision, limits of quantification, recovery, and matrix effects were sufficient to enable the measurement of metaldehyde in human blood samples. In addition, we proposed a fragmentation pathway involving ammonium adduct fragment ions for metaldehyde. Copyright © 2018. Published by Elsevier B.V.

Qualitative and quantitative determination of yohimbine in authentic yohimbe bark and in commercial aphrodisiacs by HPLC-UV-API/ MS methods.

Science.gov (United States)

Zanolari, Boris; Ndjoko, Karine; Ioset, Jean-Robert; Marston, Andrew; Hostettmann, Kurt

2003-01-01

The development and validation of a rapid qualitative and quantitative method based on an HPLC-UV-MS technique with atmospheric pressure chemical ionisation and electrospray ionisation for the analysis of yohimbine in a number of commercial aphrodisiac products is reported. HPLC with multiple-stage mass spectrometry experiments allowed the identification of the target compound and increased the selectivity of complex analyses such as those involved with multi-botanical preparations. The precision and the robustness of the method were improved by the use of two internal standards: codeine for UV detection and deuterium-labelled yohimbine for MS detection. Twenty commercial aphrodisiac preparations were analysed and the amount of yohimbine measured and expressed as the maximal dose per day suggested on product labels ranged from 1.32 to 23.16 mg.

A validated HPLC-MS/MS assay for quantifying unstable pharmacologically active metabolites of clopidogrel in human plasma: application to a clinical pharmacokinetic study.

Science.gov (United States)

Furlong, Michael T; Savant, Ishani; Yuan, Moucun; Scott, Laura; Mylott, William; Mariannino, Thomas; Kadiyala, Pathanjali; Roongta, Vikram; Arnold, Mark E

2013-05-01

Clopidogrel is prescribed for the treatment of Acute Coronary Syndrome and recent myocardial infarction, recent stroke, or established peripheral arterial disease. A sensitive and reliable high performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS) assay was developed and validated to enable reliable quantification of four diastereomeric and chemically reactive thiol metabolites, two of which are pharmacologically active, in human plasma. The metabolites were stabilized by alkylation of their reactive thiol moieties with 2-bromo-3'-methoxyacetophenone (MPB). Following organic solvent mediated-protein precipitation in a 96-well plate format, chromatographic separation was achieved by gradient elution on an Ascentis Express RP-amide column. Chromatographic conditions were optimized to ensure separation of the four derivatized active metabolites. Derivatized metabolites and stable isotope-labeled internal standards were detected by positive ion electrospray tandem mass spectrometry. The HPLC-MS/MS assay was validated over concentration ranges of 0.125-125 ng/mL for metabolites H1-H3 and 0.101-101 ng/mL for H4. Intra- and inter-assay precision values for replicate quality control samples were within 14.3% for all analytes during the assay validation. Mean quality control accuracy values were within ±6.3% of nominal values for all analytes. Assay recoveries were high (>79%). The four derivatized analytes were stable in human blood for at least 2 h at room temperature and on ice. The analytes were also stable in human plasma for at least 25 h at room temperature, 372 days at -20 °C and -70 °C, and following at least five freeze-thaw cycles. The validated assay was successfully applied to the quantification of all four thiol metabolites in human plasma in support of a human pharmacokinetic study. Copyright © 2013 Elsevier B.V. All rights reserved.

Determination of prodrug treosulfan and its biologically active monoepoxide in rat plasma, liver, lungs, kidneys, muscle, and brain by HPLC-ESI-MS/MS method.

Science.gov (United States)

Romański, Michał; Kasprzyk, Anna; Teżyk, Artur; Widerowska, Agnieszka; Żaba, Czesław; Główka, Franciszek

2017-06-05

A prodrug treosulfan (TREO) is currently investigated in clinical trials for conditioning prior to hematopoietic stem cell transplantation. Bioanalysis of TREO and its active derivatives, monoepoxide (S,S-EBDM) and diepoxide, in plasma and urine underlay the pharmacokinetic studies of these compounds but cannot explain an organ pharmacological action or toxicity. Recently, distribution of TREO and S,S-EBDM into brain, cerebrospinal fluid, and aqueous humor of the eye has been investigated in animal models and the obtained results presented clinical relevance. In this paper, a selective and rapid HPLC-ESI-MS/MS method was elaborated and validated for the studies of disposition of TREO and S,S-EBDM in rat plasma, liver, lungs, kidneys, muscle, and brain. The two analytes and codeine, internal standard (IS), were isolated from 50μL of plasma and 100μL of supernatants of the tissues homogenates using ultrafiltration Amicon vials. Chromatographic resolution was accomplished on C18 column with isocratic elution. The limits of quantitation of TREO and S,S-EBDM in the studied matrices ranged from 0.11 to 0.93μM. The HPLC-MS/MS method was adequately precise and accurate within and between runs. The IS-normalized matrix effect differed among the tissues and was the most pronounced in a liver homogenate supernatant (approximately 0.55 for TREO and 0.35 for S,S-EBDM). Stability of the analytes in experimental samples was also established. The validated method for the first time enabled determination of TREO and S,S-EBDM in the six life-important tissues in rats following administration of the prodrug. Copyright © 2017 Elsevier B.V. All rights reserved.

Metodo de quantificação de nucleotideos por HPLC-MS/MS e avaliação da atividade de analogos de sildenafil sobre fosfodiesterase

OpenAIRE

Raquel Lorenzetti

2007-01-01

Resumo: No presente trabalho foi padronizado um novo método para a dosagem da atividade de fosfodiesterase in vitro, por HPLC-MS/MS. Este novo método conseguiu apresentar exatidão, precisão, sensibilidade e rapidez nas análises; monitorando os nucleotídeos (AMP, GMP, AMPc e GMPc). O desenvolvimento de novos fármacos derivados de um protótipo aponta para a obtenção de moléculas com um melhor perfil farmacocinético ou uma melhor relação estrutura-atividade. Atualmente o sildenafil é considerad...

Examination of correlation between histidine and nickel absorption by Morus L., Robinia pseudoacacia L. and Populus nigra L. using HPLC-MS and ICP-MS.

Science.gov (United States)

Ozen, Sukran Akkus; Yaman, Mehmet

2016-08-02

In this study, HPLC-MS and ICP-MS methods were used for the determination of histidine and nickel in Morus L., Robinia pseudoacacia L., and Populus nigra L. leaves taken from industrial areas including Gaziantep and Bursa cities. In the determination of histidine by HPLC-MS, all of the system parameters such as flow rate of mobile phase, fragmentor potential, injection volume and column temperature were optimized and found to be 0.2 mL min(-1), 70 V, 15 µL, and 20°C, respectively. Under the optimum conditions, histidine was extracted from plant sample by distilled water at 90°C for 30 min. Concentrations of histidine as mg kg(-1) were found to be between 2-9 for Morus L., 6-13 for Robinia pseudoacacia L., and 2-10 for Populus nigra L. Concentrations of nickel were in the ranges of 5-10 mg kg(-1) for Morus L., 3-10 mg kg(-1) for Robinia pseudoacacia L., and 0.6-4 mg kg(-1) for Populus nigra L. A significant linear correlation (r = 0.78) between histidine and Ni was observed for Populus nigra L., whereas insignificant linear correlation for Robinia pseudoacacia L. (r = 0.22) were seen. Limits of detection (LOD) and quantitation (LOQ) were found to be 0.025 mg Ni L(-1) and 0.075 mg Ni L(-1), respectively.

Comparison of HPLC-RI, LC/MS-MS and enzymatic assays for the analysis of residual lactose in lactose-free milk.

Science.gov (United States)

Trani, A; Gambacorta, G; Loizzo, P; Cassone, A; Fasciano, C; Zambrini, A V; Faccia, M

2017-10-15

Lactose intolerance is the decreased ability to digest lactose, and the population involved is rapidly increasing all over the world. Different procedures have been reported in the literature to quantify lactose in dairy products, but the official method of analysis is based on enzymatic assay. In this paper, the effectiveness of two enzymatic kits in detecting residual lactose in lactose-free milk was investigated, and a comparison with two alternative chromatographic methods was done. The investigation used several samples of UHT milk containing different levels of lactose, and the results highlighted the inadequacy of the enzymatic assays and of the HPLC-RI method to analyse lactose-free milk. An LC-MS/MS method using the formate adduct was developed, and it allowed quantitation of lactose and lactulose in all samples at a high level of precision and repeatability. Copyright © 2017 Elsevier Ltd. All rights reserved.

Measurement of Ether Phospholipids in Human Plasma with HPLC-ELSD and LC/ESI-MS After Hydrolysis of Plasma with Phospholipase A1.

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Mawatari, Shiro; Hazeyama, Seira; Fujino, Takehiko

2016-08-01

Ethanolamine ether phospholipid (eEtnGpl) and choline ether phospholipid (eChoGpl) are present in human plasma or serum, but the relative concentration of the ether phospholipids in plasma is very low as compared to those in other tissues. Nowadays, measurement of ether phospholipids in plasma depends on tandem mass spectrometry (LC/MS/MS), but a system for LC/MS/MS is generally too expensive for usual clinical laboratories. Treatment of plasma with phospholipase A1 (PLA1) causes complete hydrolysis of diacylphospholipids, but ether phospholipids remain intact. After the treatment of plasma with PLA1, both eEtnGpl and eChoGpl are detected as independent peaks by high-performance liquid chromatography with evaporative light scattering detection (HPLC-ELSD). The same sample used for HPLC-ELSD can be applied to detect eEtnGpl and eChoGpl with electrospray ionization mass spectrometry. Presence of alkylacylphospholipids in both eChoGpl and eEtnGpl in human plasma was indicated by sequential hydrolysis of plasma with PLA1 and hydrochloric acid.

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

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

2018-05-01

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

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

International Nuclear Information System (INIS)

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

2009-01-01

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

Exorphin Peptides in Urine with HPLC-MS/MS Detection

OpenAIRE

2015-01-01

Exorphins have been found in urine from individuals diagnosed with autism spectrum disorders by HPLC techniques. However, several studies, using sophisticated analytical techniques , have reported negative findings. This made it necessary to improve our methods. The sample stability during transport and storage and the pre -analytical treatment of urines was improved by peptidase inhibition and solid ...

Characterization of bioactive compounds of Annona cherimola L. leaves using a combined approach based on HPLC-ESI-TOF-MS and NMR.

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Díaz-de-Cerio, Elixabet; Aguilera-Saez, Luis Manuel; Gómez-Caravaca, Ana María; Verardo, Vito; Fernández-Gutiérrez, Alberto; Fernández, Ignacio; Arráez-Román, David

2018-06-01

Annona cherimola Mill. (cherimoya) has widely been used as food crop. The leaves of this tree possess several health benefits, which are, in general, attributed mainly to its bioactive composition. However, literature concerning a comprehensive characterization based on a combined approach, which consists of nuclear magnetic resonance (NMR) and high-performance liquid chromatography coupled with time-of-flight mass spectrometry (HPLC-TOF-MS), from these leaves is scarce. Thus, the aim of this work was to study the polar profile of full extracts of cherimoya leaves by using these tools. Thus, a total of 77 compounds have been characterized, 12 of which were identified by both techniques. Briefly, 23 compounds were classified as amino acids, organic acids, carbohydrates, cholines, phenolic acid derivatives, and flavonoids by NMR, while 66 metabolites were divided into sugars, amino acids, phenolic acids and derivatives, flavonoids, phenylpropanoids, and other polar compounds by HPLC-TOF-MS. It is worth mentioning that different solvent mixtures were tested and the total phenolic content in the extracts quantified (TPC via HPLC-TOF-MS). The tendency observed was EtOH/water 80/20 (v/v) (17.0 ± 0.2 mg TPC/g leaf dry weight (d.w.)) ≥ acetone/water 70/30 (v/v) (16.1 ± 0.7 mg TPC/g leaf d.w.) > EtOH/water 70/30 (v/v) (14.0 ± 0.3 mg TPC/g leaf d.w.) > acetone/water 80/20 (v/v) (13.5 ± 0.4 mg TPC/g leaf d.w.). Importantly, flavonoids derivatives were between 63 and 76% of the TPC in those extracts. Major compounds were sucrose, glucose (α and β), and proline, and chlorogenic acid and rutin for NMR and HPLC-TOF-MS, respectively. Graphical abstract The combined use of LC-HRMS and NMR is a potential synergic combination for a comprehensive metabolite composition of cherimoya leaves.

A high-throughput method for the simultaneous determination of multiple mycotoxins in human and laboratory animal biological fluids and tissues by PLE and HPLC-MS/MS.

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Cao, Xiaoqin; Wu, Shuangchan; Yue, Yuan; Wang, Shi; Wang, Yuting; Tao, Li; Tian, Hui; Xie, Jianmei; Ding, Hong

2013-12-30

A high-throughput method for the determination of 28 mycotoxins involving pressurised liquid extraction (PLE) coupled with liquid chromatography-tandem mass spectrometry (HPLC-MS/MS) has been optimised and validated for determination in various biological fluids and tissues of human and laboratory animals. High-throughput analysis was achieved using PLE pre-treatment and without the need for any cleanup. The extraction solvent was acetonitrile/water/acetic acid (80/19/1, v/v/v). The static extraction time was 5min. The extraction pressure and temperature were 1500psi and 140°C, respectively. The flush volume was 60%. The limits of detection, which were defined as CCα, varied from 0.01μg/kg (μg/L) to 0.69μg/kg (μg/L). The recoveries of spiked samples from 0.20μg/kg (μg/L) to 2μg/kg (μg/L) ranged from 71% to 100.5% with relative standard deviations of less than 17.5%, except FB1 and FB2 recoveries, which were lower than 60%. The method was successfully applied in real samples, and the data indicate that this technique is a useful analytical method for the determination of mycotoxins from humans and animals. To the best of our knowledge, this method is the first for the large-scale testing of multi-class mycotoxins in all types of biological fluids and tissues that uses PLE and HPLC-MS/MS. Copyright © 2013 Elsevier B.V. All rights reserved.

Investigation of the profile and kinetics of degradation of rivaroxaban using HPLC, TLC-densitometry and LC/MS/MS: Application to pre-formulation studies

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Mohamed A. Abdallah

2015-06-01

Full Text Available Rivaroxaban (RIVA, an amide group-containing oral anticoagulant was subjected to stress conditions commonly required for the registration of pharmaceuticals: base and acid-catalyzed hydrolysis (0.1 M, 60 °C, 3–6 h, oxidation (10% H2O2, 24 h, photodegradation (300–800 nm, 24 h and thermal decomposition (50 °C, 6 h. Two major degradation products were separated and identified using TLC and LC/MS/MS, respectively. An orthogonal stability-indicating testing protocol (RP-HPLC and NP-TLC-densitometry was developed and validated according to ICH guidelines. Both assays enabled the determination of RIVA in the presence of its degradation products as well as the kinetics of degradation. Determination was carried out over a concentration range of (5.00–50.00 μg/mL and (0.40–12.00 μg/band with an accuracy of (100.81% ± 1.03 and (100.29% ± 1.08 for HPLC and TLC-densitometry, respectively. Results indicated that RIVA was stable towards oxidation, photodegradation and thermal decomposition but extremely sensitive to hydrolysis. Two major degradation products were detected in the case of base-catalyzed hydrolysis while only one degradation product was detected upon acid-catalyzed hydrolysis. This could be attributed to the presence of amide groups in RIVA structure of different stability profiles. The kinetics of hydrolysis was investigated in more detail and the reaction was found to follow the pseudo first order kinetics, as confirmed by the results of both HPLC and TLC-densitometric assays. The applicability of the assay for the determination of RIVA content and dissolution pattern of the innovator product as well as three generic formulations was demonstrated.

Antibiotic use in heavy pigs: Comparison between urine and muscle samples from food chain animals analysed by HPLC-MS/MS.

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Chiesa, Luca Maria; Nobile, Maria; Panseri, Sara; Arioli, Francesco

2017-11-15

The antibiotic overuse in zoothechnics, due to prophylactic and therapeutic treatments, or to their growth-promoting activity, is a major cause for the onset of widespread antibiotic resistance. Of particular relevance to this study, is the antibiotic abuse in pig breeding. Despite the comprehensive literature on residue controls in pig muscle, data on pig urine, a non-invasive, on-farm collectable matrix, are lacking. Therefore, we validated an HPLC-MS/MS method to detect 29 antimicrobials from eight classes and applied it to 43 anonymous pig urine and muscle paired samples and fulfilled the parameters in agreement with the Commission Decision 2002/657/UE. The analytical limits were moreover much lower than the maximum residue limits (MRLs) required by the Commission Regulation 37/2010/UE. In the samples, antibiotics were usually detected at higher frequencies and concentrations in urine than muscle. Urine proved a useful tool to detect antibiotic administration and their excessive use in pig farming is depicted. Copyright © 2017. Published by Elsevier Ltd.

Tannin analysis of chestnut bark samples (Castanea sativa Mill.) by HPLC-DAD-MS.

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Comandini, Patrizia; Lerma-García, María Jesús; Simó-Alfonso, Ernesto Francisco; Toschi, Tullia Gallina

2014-08-15

In the present investigation, an HPLC-DAD/ESI-MS method for the complete analysis of tannins and other phenolic compounds of different commercial chestnut bark samples was developed. A total of seven compounds (vescalin, castalin, gallic acid, vescalagin, 1-O-galloyl castalagin, castalagin and ellagic acid) were separated and quantified, being 1-O-galloyl castalagin tentatively identified and found for the first time in chestnut bark samples. Thus, this method provided information regarding the composition and quality of chestnut bark samples, which is required since these samples are commercialised due to their biochemical properties as ingredients of food supplements. Copyright © 2014 Elsevier Ltd. All rights reserved.

Novel Tyrosine Phosphorylation Sites in Rat Skeletal Muscle Revealed by Phosphopeptide Enrichment and HPLC-ESI-MS/MS

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Zhang, Xiangmin; Højlund, Kurt; Luo, Moulun; Meyer, Christian; Thangiah, Geetha; Yi, Zhengping

2012-01-01

Tyrosine phosphorylation plays a fundamental role in many cellular processes including differentiation, growth and insulin signaling. In insulin resistant muscle, aberrant tyrosine phosphorylation of several proteins has been detected. However, due to the low abundance of tyrosine phosphorylation (tyrosine phosphorylation sites have been identified in mammalian skeletal muscle to date. Here, we used immunoprecipitation of phosphotyrosine peptides prior to HPLC-ESI-MS/MS analysis to improve the discovery of tyrosine phosphorylation in relatively small skeletal muscle biopsies from rats. This resulted in the identification of 87 distinctly localized tyrosine phosphorylation sites in 46 muscle proteins. Among them, 31 appear to be novel. The tyrosine phosphorylated proteins included major enzymes in the glycolytic pathway and glycogen metabolism, sarcomeric proteins, and proteins involved in Ca2+ homeostasis and phosphocreatine resynthesis. Among proteins regulated by insulin, we found tyrosine phosphorylation sites in glycogen synthase, and two of its inhibitors, GSK-3α and DYRK1A. Moreover, tyrosine phosphorylation sites were identified in several MAP kinases and a protein tyrosine phosphatase, SHPTP2. These results provide the largest catalogue of mammalian skeletal muscle tyrosine phosphorylation sites to date and provide novel targets for the investigation of human skeletal muscle phosphoproteins in various disease states. PMID:22609512

Isotopic Exchange HPLC-HRMS/MS Applied to Cyclic Proanthocyanidins in Wine and Cranberries

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Longo, Edoardo; Rossetti, Fabrizio; Scampicchio, Matteo; Boselli, Emanuele

2018-01-01

Cyclic B-type proanthocyanidins in red wines and grapes have been discovered recently. However, proanthocyanidins of a different chemical structure (non-cyclic A-type proanthocyanidins) already known to be present in cranberries and wine possess an identical theoretical mass. As a matter of fact, the retention times and the MS/MS fragmentations found for the proposed novel cyclic B-type tetrameric proanthocyanidin in red wine and the known tetrameric proanthocyanidin in a cranberry extract are herein shown to be identical. Thus, hydrogen/deuterium (H/D) exchange was applied to HPLC-HRMS/MS to confirm the actual chemical structure of the new oligomeric proanthocyanidins. The comparison of the results in water and deuterium oxide and between wine and cranberry extract indicates that the cyclic B-type tetrameric proanthocyanidin is the actual constituent of the recently proposed novel tetrameric species ([C60H49O24]+, m/z 1153.2608). Surprisingly, the same compound was also identified as the main tetrameric proanthocyanidin in cranberries. Finally, a totally new cyclic B-type hexameric proanthocyanidin ([C90H73O36]+, m/z 1729.3876) belonging to this novel class was identified for the first time in red wine. [Figure not available: see fulltext.

The integrated quality assessment of Chinese commercial dry red wine based on a method of online HPLC-DAD-CL combined with HPLC-ESI-MS.

Science.gov (United States)

Yu, Hai-Xiang; Sun, Li-Qiong; Qi, Jin

2014-07-01

To apply an integrated quality assessment strategy to investigate the quality of multiple Chinese commercial dry red wine samples. A comprehensive method was developed by combining a high performance liquid chromatography-diode array detector-chemiluminescence (HPLC-DAD-CL) online hyphenated system with an HPLC-ESI-MS technique. Chromatographic and H2O2-scavenging active fingerprints of thirteen batches of different, commercially available Chinese dry red wine samples were obtained and analyzed. Twenty-five compounds, including eighteen antioxidants were identified and evaluated. The dominant and characteristic antioxidants in the samples were identified. The relationships between antioxidant potency and the cultivated variety of grape, producing area, cellaring period, and trade mark are also discussed. The results provide the feasibility for an integrated quality assessment strategy to be efficiently and objectively used in quality (especially antioxidant activity) assessment and identification of dry red wine. Copyright © 2014 China Pharmaceutical University. Published by Elsevier B.V. All rights reserved.

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

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

2018-05-10

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

Determination of Irgarol-1051 and its related s-triazine species in coastal sediments and mussel tissues by HPLC-ESI-MS/MS.

Science.gov (United States)

Tsang, Vic Wing-Hang; Lei, Ngai-Yu; Lam, Michael Hon-Wah

2009-10-01

A mild, low-temperature analytical approach based on sonication assisted extraction coupled with HPLC electrospray ionization triple quadrupole tandem mass spectrometry has been developed for the simultaneous qualitative and quantitative determination of the four Irgarol-related s-triazine species, namely Irgarol-1051, M1, M2 and M3, in coastal sediments and Green-lipped mussel samples. Mild extraction conditions were necessary for the preservation of the thermally unstable M2. The Multiple Reaction Monitoring (MRM) mode of detection by ESI-MS/MS enabled reliable qualitative identification and sensitive quantitative determination of those s-triazines. This determination method was applied to evaluate the degree of Irgarol-1051 contamination in the sediments and biota of the coastal environment of Hong Kong--one of the busiest maritime ports in the world. All the four s-triazine species were observed in all of the samples. This is the first time that the newly identified M2 and M3 are detected in coastal sediments and biota tissues.

Simultaneous determination of five free and total flavonoids in rat plasma by ultra HPLC-MS/MS and its application to a comparative pharmacokinetic study in normal and hyperlipidemic rats.

Science.gov (United States)

Wang, Xiaofan; Zhao, Xu; Gu, Liqiang; Lv, Chunxiao; He, Bosai; Liu, Zhenzhen; Hou, Pengyi; Bi, Kaishun; Chen, Xiaohui

2014-03-15

A simple and rapid ultra-high performance liquid chromatography-tandem mass spectrometry (uHPLC-MS/MS) method has been developed for the simultaneous determination of five free flavonoids (amentoflavone, isorhamnetin, naringenin, kaempferol and quercetin) and their total (free and conjugated) forms, and to compare the pharmacokinetics of these active ingredients in normal and hyperlipidemic rats. The free and total forms of these flavonoids were extracted by liquid-liquid extraction with ethyl acetate. The conjugated flavonoids were deconjugated by the enzyme β-Glucuronidase and Sulfatase. Chromatographic separation was accomplished on a ZORBAX Eclipse XDB-C8 USP L7 column using gradient elution. Detection was performed on a 4000Q uHPLC-MS/MS system from AB Sciex using negative ion mode in the multiple reaction monitoring (MRM) mode. The lower limits of quantification were 2.0-5.0ng/mL for all the analytes. Intra-day and inter-day precision were less than 15% and accuracy ranged from -9.3% to 11.0%, and the mean extraction recoveries of analytes and internal standard (IS) from rat plasma were all more than 81.7%. The validated method was successfully applied to a comparative pharmacokinetic study of five free and total analytes in rat plasma. The results indicated that the absorption of five total flavonoids in hyperlipidemia group were significantly higher than those in normal group with similar concentration-time curves. Copyright © 2014 Elsevier B.V. All rights reserved.

Pyrrolizidine alkaloids in the food chain: development, validation, and application of a new HPLC-ESI-MS/MS sum parameter method.

Science.gov (United States)

Cramer, Luise; Schiebel, Hans-Martin; Ernst, Ludger; Beuerle, Till

2013-11-27

Contamination of food and feed with pyrrolizidine alkaloids is currently discussed as a potential health risk. Here, we report the development of a new HPLC-ESI-MS/MS sum parameter method to quantitate the pyrrolizidine alkaloid content in complex food matrices. The procedure was validated for honey and culinary herbs. Isotopically labeled 7-O-9-O-dibutyroyl-[9,9-(2)H2]-retronecine was synthesized and utilized as an internal standard for validation and quantitation. The total pyrrolizidine alkaloid content of a sample is expressed as a single sum parameter: retronecine equivalents (RE). Ld/Lq for honey was 0.1 μg RE/kg/0.3 μg RE/kg. For culinary herbs, 1.0 μg RE/kg/3.0 μg RE/kg (dry weight, dw) and 0.1 μg RE/kg/0.3 μg RE/kg (fresh weight, fw) were determined, respectively. The new method was applied to analyze 21 herbal convenience products. Fifteen products (71%) were pyrrolizidine alkaloid positive showing pyrrolizidine alkaloid concentrations ranging from 0.9 to 74 μg RE/kg fw.

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

International Nuclear Information System (INIS)

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

2011-01-01

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

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

Science.gov (United States)

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

2016-05-30

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

[Evaluation of Brodifacoum-induced Toxicity by Metabonomics Approach Based on HPLC-TOF-MS].

Science.gov (United States)

Yan, H; Zhuo, X Y; Shen, B H; Xiang, P; Shen, M

2017-06-01

To analyse the metabolic changes in urine of rats with brodifacoum intoxication, and to reveal the molecular mechanism of brodifacoum-induced toxicity on rats. By establishing a brodifacoum poisoning rats model, the urine metabolic profiling data of rats were acquired using high performance liquid chromatography-time of flight mass spectrometry （HPLC-TOF-MS）. The orthogonal partial least squares analysis-discrimination analysis （OPLS-DA） was applied for the multivariate statistics and the discovery of differential metabolites closely related to toxicity of brodifacoum. OPLS-DA score plot showed that the urinary metabolic at different time points before and after drug administration had good similarity within time period and presented clustering phenomenon. Comparing the urine samples of rats before drug administration with which after drug administration, twenty-two metabolites related to brodifacoum-induced toxicity were selected. The toxic effect of brodifacoum worked by disturbing the metabolic pathways in rats such as tricarboxylic cycle, glycolysis, sphingolipid metabolism and tryptophan metabolism, and the toxicity of brodifacoum is characterized of accumulation effect. The metabonomic method based on urine HPLC-TOF-MS can provide a novel insight into the study on molecular mechanism of brodifacoum-induced toxicity. Copyright© by the Editorial Department of Journal of Forensic Medicine

Qualitative Analysis of Polyphenols in Macroporous Resin Pretreated Pomegranate Husk Extract by HPLC-QTOF-MS.

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Abdulla, Rahima; Mansur, Sanawar; Lai, Haizhong; Ubul, Ablikim; Sun, Guangying; Huang, Guozheng; Aisa, Haji Akber

2017-09-01

Pomegranate (Punica granatum L.) husk is a traditional herbal medicine abundant in phenolic compounds and plays some roles in the treatment of oxidative stress, bacterial and viral infection, diabetes mellitus, and acute and chronic inflammation. Identification and determination of polyphenols in macroporous resin pretreated pomegranate husk extract by high performance liquid chromatography coupled with quadrupole time-of-flight tandem mass spectrometry (HPLC-QTOF-MS). The total polyphenols of pomegranate husk were prepared by ethanol extraction followed by pretreatment with HPD-300 macroporous resin. The polyphenolic compounds were qualitatively analysed by HPLC-QTOF-MS in negative electrospray ionisation (ESI) mode at different collision energy (CE) values. A total of 50 polyphenols were detected in the extract of pomegranate husk, including 35 hydrolysable tannins and 15 flavonoids with distinct retention time, fragmentation behaviours and characteristics, and the accurate mass-to-charge ratios at low, moderate and high CE values. Of these, we identified nine compounds for the first time in the pomegranate husk, including hexahydroxydiphenoyl-valoneoyl-glucoside (HHDP-valoneyl-glucoside), galloyl-O-punicalin, rutin, hyperoside, quercimeritrin, kaempferol-7-O-rhahmano-glucoside, luteolin-3'-O-arabinoside, luteolin-3'-O-glucoside, and luteolin-4'-O-glucoside. To validate the specificity and accuracy of mass spectrometry in the detection of polyphenols, as compared to the fragmentation pathways of granatin B in detail, including the HHDP-valoneyl- glucoside was first identified from pomegranate husk. The study provides evidence for the quality control and development of novel drugs based on polyphenols from the pomegranate husk. Copyright © 2017 John Wiley & Sons, Ltd. Copyright © 2017 John Wiley & Sons, Ltd.

A sensitive HPLC-MS/MS method for the simultaneous detection of microbial transglutaminase, and bovine and porcine fibrinogen/thrombin in restructured meat.

Science.gov (United States)

Jira, Wolfgang; Schwägele, Fredi

2017-12-15

A sensitive HPLC-MS/MS method for the simultaneous detection of microbial transglutaminase (TG) from Streptomyces mobaraensis, and bovine and porcine fibrinogen/thrombin in restructured meat was developed using tryptic marker peptides of TG (five markers), and bovine and porcine fibrinogen (six markers each). Meat binding experiments with beef and pork were performed using a technical TG mixture (Activa, Ajinomoto), and bovine and porcine plasmapowder FG (PPFG; Sonac B.V.). The method developed allows the simultaneous detection of the use of these cold-set binders in raw and heated samples. The peak areas of the fibrinogen marker peptides were increased by a factor of about 100, compared to blank values originating from the occurrence of residual blood in meat, using a concentration of 0.6% bovine and porcine PPFG. A differentiation between the use of blood plasma powder and PPFG using the ratios of fibrinogen to serotransferrin peptide peak areas seems to be possible. Copyright © 2017 Elsevier Ltd. All rights reserved.

Screening and Identifying Antioxidative Components in Ginkgo biloba Pollen by DPPH-HPLC-PAD Coupled with HPLC-ESI-MS2

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Netrusov, A. I.; Zhou, Qingxin; Guo, Danyang; Liu, Xiaoyong; He, Hailun; Xin, Xue; Wang, Yifen; Chen, Leilei

2017-01-01

The Ginkgo biloba is one of ancient trees that exists from billions of years ago, its leaf and nut are used as herbs and foods in China, while so far its pollen does not have any application except pollination. In order to evaluate the antioxidant activity of Ginkgo biloba pollen, and rapidly screen its antioxidative components, the 1,1-diphenyl-2-picrylhydrazyl (DPPH) scavenging ability, total flavonoid, total phenol, and proanthocyanidin of Ginkgo biloba pollen were determined and compared with those of Ginkgo biloba leaf and nut, and the off-line DPPH-HPLC-PAD and HPLC-ESI-MS2 were applied for screening and identifying the antioxidant flavonoids in Ginkgo biloba pollen. The results showed that the DPPH scavenging ability of Ginkgo biloba pollen was much higher than Ginkgo biloba nut, but lower than Ginkgo biloba leaf, while the total content of flavonoid in Ginkgo biloba pollen was approximately 4.37 times higher than in Ginkgo biloba leaf. Further studies found that the major flavonol aglycone in Ginkgo biloba pollen was kaempferol, which accounted for 96.71% of the total aglycones (includes quercetin, kaempferol and isorhamnetin), and the main flavonoid components in Ginkgo biloba pollen were flavonoid glycosides. Finally, ten antioxidant peaks were screened and identified to be flavonoids (including kaempferol and nine flavonoid glycosides), so flavonoids were likely to be the main antioxidant components in GP, and among them, three novel kaempferol glycosides (peaks 1, 2, and 3) were found in Ginkgo biloba pollen for the first time, which had never been found in Ginkgo biloba. PMID:28095510

Identification and determination of the major constituents in traditional Chinese medicine Longdan Xiegan Pill by HPLC-DAD-ESI-MS

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Hui Liu

2011-02-01

Full Text Available A novel and sensitive HPLC-UV method has been developed for the simultaneous determination of twelve major compounds in Longdan Xiegan Pill. The chemical profile of the twelve compounds, including geniposidic acid (1, geniposide(2, gentiopicroside(3, liquiritin(4, crocin(5, baicalin(6, wogonoside(7, baicalein(8, glycyrrhizic acid (9, wogonin (10, oroxylin A (11 and aristolochic acid A (12, was acquired using high-performance liquid chromatography-diode array detector coupled with an electrospray tandem mass spectrometer (HPLC-DAD-ESI-MS. The analysis was performed on a Dikma Platisil ODS C18 column (250 mm × 4. 6 mm, 5 μm with a gradient solvent system of acetonitrile-0. 1% aqueous formic acid. The validation was carried out and the linearities (r > 0. 9996, repeatability (RSD<1. 8%, intra- and inter-day precision (RSD< 1. 3%, and recoveries (ranging from 96. 6% to 103. 4% were acceptable. The limits of detection (LOD of these compounds ranged from 0.29 to 4. 17 ng. Aristolochic acid A, which is the toxic ingredient, was not detected in all the batches of Longdan Xiegan Pill. Furthermore, hierarchical cluster analysis was used to evaluate the variation of the herbal prescription. The proposed method is simple, effective and suitable for the quality control of this traditional Chinese medicine (TCM. Keywords: Longdan Xiegan Pill, high-performance liquid chromatography-diode array detector coupled with an electrospray tandem mass spectrometer (HPLC-DAD-ESI-MS, qualitative evaluation, aristolochic acid A, hierarchical cluster analysis

HepG2 cells biospecific extraction and HPLC-ESI-MS analysis for screening potential antiatherosclerotic active components in Bupeuri radix.

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Liu, Shuqiang; Tan, Zhibin; Li, Pingting; Gao, Xiaoling; Zeng, Yuaner; Wang, Shuling

2016-03-20

HepG2 cells biospecific extraction method and high performance liquid chromatography-electrospray ionization-mass spectrometry (HPLC-ESI-MS) analysis was proposed for screening of potential antiatherosclerotic active components in Bupeuri radix, a well-known Traditional Chinese Medicine (TCM). The hypothesis suggested that when cells are incubated together with the extracts of TCM, the potential bioactive components in the TCM should selectively combine with the receptor or channel of HepG2 cells, then the eluate which contained biospecific component binding to HepG2 cells was identified using HPLC-ESI-MS analysis. The potential bioactive components of Bupeuri radix were investigated using the proposed approach. Five compounds in the saikosaponins of Bupeuri radix were detected as these components selectively combined with HepG2 cells, among these compounds, two potentially bioactive compounds namely saikosaponin b1 and saikosaponin b2 (SSb2) were identified by comparing with the chromatography of the standard sample and analysis of the structural clearance characterization of MS. Then SSb2 was used to assess the uptake of DiI-high density lipoprotein (HDL) in HepG2 cells for antiatherosclerotic activity. The results have showed that SSb2, with indicated concentrations (5, 15, 25, and 40 μM) could remarkably uptake dioctadecylindocarbocyanine labeled- (DiI) -HDL in HepG2 cells (Vs control group, *PESI-MS analysis is a rapid, convenient, and reliable method for screening potential bioactive components in TCM and SSb2 may be a valuable novel drug agent for the treatment of atherosclerosis. Copyright © 2016 Elsevier B.V. All rights reserved.

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

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

1999-07-01

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

Rapid and automated on-line solid phase extraction HPLC-MS/MS with peak focusing for the determination of ochratoxin A in wine samples.

Science.gov (United States)

Campone, Luca; Piccinelli, Anna Lisa; Celano, Rita; Pagano, Imma; Russo, Mariateresa; Rastrelli, Luca

2018-04-01

This study reports a fast and automated analytical procedure based on an on-line SPE-HPLC-MS/MS method for the automatic pre-concentration, clean up and sensitive determination of OTA in wine. The amount of OTA contained in 100μL of sample (pH≅5.5) was retained and concentrated on an Oasis MAX SPE cartridge. After a washing step to remove matrix interferents, the analyte was eluted in back-flush mode and the eluent from the SPE column was diluted through a mixing Tee, using an aqueous solution before the chromatographic separation achieved on a monolithic column. The developed method has been validated according to EU regulation N. 519/2014 and applied for the analysis of 41 red and 17 white wines. The developed method features minimal sample handling, low solvent consumption, high sample throughput, low analysis cost and provides an accurate and highly selective results. Copyright © 2017 Elsevier Ltd. All rights reserved.

Simultaneous quantification of five steroid saponins from Dioscorea zingiberensis C.H.Wright in rat plasma by HPLC-MS/MS and its application to the pharmacokinetic studies

Science.gov (United States)

Zhang, Xinxin; Li, Jing; Ito, Yoichiro; Sun, Wenji

2014-01-01

A simple, reliable and sensitive high-performance liquid chromatography tandem mass spectrometry method (HPLC-MS/MS) was established for simultaneous analyses of the following 5 steroid saponins in rat plasma after the single dose administration of total steroid saponins extracted from the rhizome of Dioscorea zingiberensis C.H.Wright for the first time. Protodioscin, huangjiangsu A, zingiberensis new saponin, dioscin, and gracillin were quantified using ginsenoside Rb1 as the internal standard (IS). The plasma samples were pretreated by a single step acetonitrile-mediated protein precipitation. The chromatographic separation was performed on an Inersil ODS-3 C18 column (250 mm × 4.6 mm, 5 μm) with the mobile phase composed of acetonitrile and water containing 0.1% formic acid under a gradient elution mode at 0.2 mL min−1 using a microsplit after the eluent from the HPLC apparatus. The quantification was accomplished on a triple quadrupole tandem mass spectrometer using the multiple reaction monitoring (MRM) in the positive ionization mode. The above five analytes were stable under sample storage and preparation conditions applied in the present study. The linearity, precision, accuracy, and recoveries of the analysis confirmed the requirements for quality-control purposes. After validation, this proposed method was successfully adopted to investigate the pharmacokinetic parameters of these five analytes. PMID:25201262

Glucosinolate diversity within a phylogenetic framework of the tribe Cardamineae (Brassicaceae) unraveled with HPLC-MS/MS and NMR-based analytical distinction of 70 desulfoglucosinolates.

Science.gov (United States)

Olsen, Carl Erik; Huang, Xiao-Chen; Hansen, Cecilie I C; Cipollini, Don; Ørgaard, Marian; Matthes, Annemarie; Geu-Flores, Fernando; Koch, Marcus A; Agerbirk, Niels

2016-12-01

As a basis for future investigations of evolutionary trajectories and biosynthetic mechanisms underlying variations in glucosinolate structures, we screened members of the crucifer tribe Cardamineae by HPLC-MS/MS, isolated and identified glucosinolates by NMR, searched the literature for previous data for the tribe, and collected HPLC-MS/MS data for nearly all glucosinolates known from the tribe as well as some related structures (70 in total). This is a considerable proportion of the approximately 142 currently documented natural glucosinolates. Calibration with authentic references allowed distinction (or elucidation) of isomers in many cases, such as distinction of β-hydroxyls, methylthios, methylsulfinyls and methylsulfonyls. A mechanism for fragmentation of secondary β-hydroxyls in MS was elucidated, and two novel glucosinolates were discovered: 2-hydroxy-3-methylpentylglucosinolate in roots of Cardamine pratensis and 2-hydroxy-8-(methylsulfinyl)octylglucosinolate in seeds of Rorippa amphibia. A large number of glucosinolates (ca. 54 with high structural certainty and a further 28 or more suggested from tandem MS), representing a wide structural variation, is documented from the tribe. This included glucosinolates apparently derived from Met, Phe, Trp, Val/Leu, Ile and higher homologues. Normal side chain elongation and side chain decoration by oxidation or methylation was observed, as well as rare abnormal side chain decoration (hydroxylation of aliphatics at the δ rather than β-position). Some species had diverse profiles, e.g. R. amphibia and C. pratensis (19 and 16 individual glucosinolates, respectively), comparable to total diversity in literature reports of Armoracia rusticana (17?), Barbarea vulgaris (20-24), and Rorippa indica (>20?). The ancestor or the tribe would appear to have used Trp, Met, and homoPhe as glucosinolate precursor amino acids, and to exhibit oxidation of thio to sulfinyl, formation of alkenyls, β-hydroxylation of aliphatic

HPLC-DAD-ESI/MS Identification of Light Harvesting and Light Screening Pigments in the Lake Sediments at Edmonson Point

OpenAIRE

Giovannetti, Rita; Alibabaei, Leila; Zannotti, Marco; Ferraro, Stefano; Petetta, Laura

2013-01-01

The composition of sedimentary pigments in the Antarctic lake at Edmonson Point has been investigated and compared with the aim to provide a useful analytical method for pigments separation and identification, providing reference data for future assessment of possible changes in environmental conditions. Reversed phase high performance liquid chromatography (HPLC) with electrospray-mass spectrometry (ESI-MS) detection and diode array detection (DAD) has been used to identify light screeni...

Removal of acidic interferences in multi-pesticides residue analysis of fruits using modified magnetic nanoparticles prior to determination via ultra-HPLC-MS/MS

International Nuclear Information System (INIS)

Qi, Peipei; Wang, Zhiwei; Yang, Guiling; Wang, Xinquan; Shang, Chunqing; Xu, Hao; Wang, Xiangyun; Zhang, Hu; Wang, Qiang

2015-01-01

The authors describe magnetite (Fe 3 O 4 ) nanoparticles modified with 3-(N,N-diethylamino) propyltrimethoxysilane (Fe 3 O 4 -PSA NPs) for use as a sorbent for dispersive solid phase extraction of pesticide residues. The Fe 3 O 4 -PSA NPs were prepared by silanizing Fe 3 O 4 NPs and modifying them with 3-(N,N-diethylamino) propyltrimethoxysilane. Field-emission scanning electron microscopy, FTIR and zeta potential measurements were employed to characterize the modified NPs. They were then used as an adsorbent to remove acidic interferences (such as malic acid and succinic acid), which are major interferences in LC-MS/MS analysis in causing ion suppression in the MS spectra of pesticides. In addition, graphitized carbon black (GCB) was used as an adsorbent to eliminate interferences by pigments. The use of Fe 3 O 4 -PSA NPs can replace time-consuming centrifugation as used in the so-called QuEChERS (quick, easy, cheap, effective, rugged and safe) method. This improvement is particularly significant in high-throughput analysis. Following the optimization of the quantities of Fe 3 O 4 -PSA NPs and GCB, the method was applied to the determination of 56 pesticides in (spiked) fruits (apple, kiwi, orange and pear) by ultra-HPLC-MS/MS. The analytical ranges typically extend from 1 to 200 ng∙mL −1 , and recoveries range from 60.2 to 130 % at different concentrations of all four kinds of fruits. The LOQs for the pesticides are 10 ng∙kg −1 , which makes the method a viable tool for pesticide monitoring in fruits. (author)

HPLC-ESI-MS Characterization of Certain Polyphenolic Compounds of Carica papaya L. Fruit Extracts and Evaluation of Their Potential Against Murine Schistosomiasis mansoni.

Science.gov (United States)

Abdel-Lateef, Ezzat El-Sayed; Rabia, Ibrahim Aly; El-Sayed, Mortada Mohamed; Abdel-Hameed, El-Sayed Saleh

2018-04-10

The in vivo antischistosomal activities of Carica papaya L. extracts were evaluated and the characterization of the active secondary metabolites of the defatted methanolic extract was performed using HPLC-ESI-MS. The plant fruit powders were extracted with 85% methanol and fractionated using organic solvents. The in vivo antischistosomal effects of the methanolic extracts and its fractions, as well as the assessment of the relationship between the antischistosomal activity of these plant extracts and oxidative stress, was determined. In addition, the defatted methanolic extract was characterized by HPLC-ESI-MS analysis. The number of worms, ova, and the Oogram pattern displayed typical Schistosoma mansoni pathology 8 weeks after infection in mice. Treatment of the infected group with the defatted methanolic extracts significantly decreased worm burden, immature ova and mature ova, while increasing the percentage of dead ova in vivo. The butanol fraction was the most effective fraction reducing worm burden by 77%, ova count in the intestine by 76% and in the liver by 80%, and significantly decreased immature and mature ova ( P group. Additionally, the defatted methanolic extracts improved the reduced glutathione and malondialdehyde levels in hepatic tissues in the treated groups compared to the infected group. The HPLC-ESI-MS analysis of the Carica papaya defatted methanolic extract revealed the presence of several polyphenolic compounds. Carica papaya fruit extracts are rich with phenolic acids and flavonoids and show a significant effect against S. mansoni infections which may be used alternative to PZQ as anti-schistosomal drug against schistosomiasis. © Georg Thieme Verlag KG Stuttgart · New York.

Chemical fingerprinting and quantitative analysis of a Panax notoginseng preparation using HPLC-UV and HPLC-MS

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Shao Qing

2011-02-01

Full Text Available Abstract Background Xuesaitong (XST injection, consisting of total saponins from Panax notoginseng, was widely used for the treatment of cardio- and cerebro-vascular diseases in China. This study develops a simple and global quality evaluation method for the quality control of XST. Methods High performance liquid chromatography-ultraviolet detection (HPLC-UV was used to identify and quantify the chromatographic fingerprints of the XST injection. Characteristic common peaks were identified using HPLC with photo diode array detection/electrospray ionization tandem mass spectrometry (HPLC-PDA/ESI-MSn. Results Representative fingerprints from ten batches of samples showed 27 'common saponins' all of which were identified and quantified using ten reference saponins. Conclusion Chemical fingerprinting and quantitative analysis identified most of the common saponins for the quality control of P. notoginseng products such as the XST injection.

Characterization of flavonoids and phenolic acids in Myrcia bella Cambess. using FIA-ESI-IT-MS(n) and HPLC-PAD-ESI-IT-MS combined with NMR.

Science.gov (United States)

Saldanha, Luiz L; Vilegas, Wagner; Dokkedal, Anne L

2013-07-16

The leaves of Myrcia DC. ex Guill species are used in traditional medicine and are also exploited commercially as herbal drugs for the treatment of diabetes mellitus. The present work aimed to assess the qualitative and quantitative profiles of M. bella hydroalcoholic extract, due to these uses, since the existing legislation in Brazil determines that a standard method must be developed in order to be used for quality control of raw plant materials. The current study identified eleven known flavonoid-O-glycosides and six acylated flavonoid derivatives of myricetin and quercetin, together with two kaempferol glycosides and phenolic acids such as caffeic acid, ethil galate, gallic acid and quinic acid. In total, 24 constituents were characterized, by means of extensive preparative chromatographic analyses, along with MS and NMR techniques. An HPLC-PAD-ESI-IT-MS and FIA-ESI-IT-MS(n) method were developed for rapid identification of acylated flavonoids, flavonoid-O-glycosides derivatives of myricetin and quercetin and phenolic acids in the hydroalcoholic M. bella leaves extract. The FIA-ESI-IT-MS techinique is a powerful tool for direct and rapid identification of the constituents after isolation and NMR characterization. Thus, it could be used as an initial method for identification of authentic samples concerning quality control of Myrcia spp extracts.

Measurement of caffeine and its three primary metabolites in human plasma by HPLC-ESI-MS/MS and clinical application.

Science.gov (United States)

Chen, Feng; Hu, Zhe-Yi; Parker, Robert B; Laizure, S Casey

2017-06-01

Caffeine is a mild stimulant with significant potential for abuse, being consumed in larger doses with the widespread availability of energy drinks and by novel routes of administration such as inspired powder, oral sprays and electronic cigarettes. How these recent changes in caffeine consumption affecting caffeine disposition and abuse potential is of growing concern. In the study of caffeine disposition in humans, it is common to only measure the caffeine concentration; however, caffeine's three major metabolites (paraxanthine, theobromine and theophylline) retain central nervous system stimulant activity that may contribute to the overall pharmacological activity and toxicity. Therefore, it would be scientifically more rigorous to measure caffeine and its major metabolites in the evaluation of caffeine disposition in human subjects. Herein, we report a method for the simultaneous quantification of caffeine and its three major metabolites in human plasma by high-performance liquid chromatography coupled to electrospray tandem mass spectrometry (HPLC-ESI-MS/MS). Human plasma samples were treated by simple protein precipitation and the analytes were separated using a 6 min gradient program. Precision and accuracy were well within in the 15% acceptance range. The simple sample preparation, short runtime, sensitivity and the inclusion of caffeine's major metabolites make this assay methodology optimal for the study of caffeine's pharmacokinetics and pharmacodynamics in human subjects. Copyright © 2016 John Wiley & Sons, Ltd.

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

Science.gov (United States)

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

2007-05-01

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

Simultaneous quantification of tafetinib (SIM010603), a novel potent inhibitor of receptor tyrosine kinase, and its major metabolite in dog plasma by HPLC-ESI/MS/MS and its application to a pharmacokinetic study.

Science.gov (United States)

Shao, Feng; Zhu, Tian; Tang, Feng; Liu, Xin

2013-01-01

This study presents a high-performance liquid chromatography-electrospray ionization-tandem mass spectrometry (HPLC-ESI/MS/MS) technique for the simultaneous determination of tafetinib (SIM010603) and its main metabolite (M1) in dog plasma by using Prazosin hydrochloric acid as the internal standard (IS). Both compounds were extracted from dog plasma with ethyl acetate and were separated by HPLC on a reversed phase C₁₈ column with a mobile phase of 10 mM ammonium acetate buffer containing 0.1% formic acid-acetonitrile (40:60, v/v) at a flow rate of 0.2 mL/min. For quantification, the triple-quadruple MS was used in selected reaction monitoring (SRM) mode. The monitored transitions were m/z 425.3 → 309.2 for tafetinib, m/z 397.2 → 309.2 for M1 and m/z 384.2 → 247.1 for IS. The developed method had a short run time of 4 min and good linearity was observed over a wide range of 1-1000 ng/mL for the two compounds. The method was successfully applied in the pharmacokinetic study of tafetinib and M1 in dog. Copyright © 2013 Elsevier B.V. All rights reserved.

Comparative study of fourteen alkaloids from Uncaria rhynchophylla hooks and leaves using HPLC-diode array detection-atmospheric pressure chemical ionization/MS method.

Science.gov (United States)

Qu, Jialin; Gong, Tianxing; Ma, Bin; Zhang, Lin; Kano, Yoshihiro; Yuan, Dan

2012-01-01

The purpose of the study is to compare alkaloid profile of Uncaria rhynchophylla hooks and leaves. Ten oxindole alkaloids and four glycosidic indole alkaloids were identified using HPLC-diode array detection (DAD) or LC-atmospheric pressure chemical ionization (APCI)-MS method, and a HPLC-UV method for simultaneous quantification of major alkaloids was validated. The hooks are characterized by high levels of four oxindole alkaloids rhynchophylline (R), isorhynchophylline (IR), corynoxeine (C) and isocorynoxeine (IC), while the leaves contained high level of two glycosidic indole alkaloids vincoside lactam (VL) and strictosidine (S). The presented methods have proven its usefulness in chemical characterization of U. rhynchophylla hooks and leaves.

The application of HPLC with on-line coupled UV/MS-biochemical detection for isolation of an acetylcholinesterase inhibitor from Narcissus 'Sir Winston Churchill'

NARCIS (Netherlands)

Ingkaninan, K.; Hazekamp, A.; de Best, C.M.; Irth, H.; Tjaden, U.R.; van der Heijden, R.; van der Greef, J.; Verpoorte, R.

2000-01-01

An HPLC with on-line coupled UV/MS-biochemical detection method for acetylcholinesterase (AChE) inhibitors in natural sources has been developed. The potential of this method is shown by the isolation of a new AChE inhibitor from the alcoholic extract of Narcissus 'Sir Winston Churchill'. Combining

Solvent optimization on Taxol extraction from Taxus baccata L., using HPLC and LC-MS

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H Sadeghi-aliabadi

2009-10-01

Full Text Available "nBackground and the purpose of the study: Taxol, a natural antitumor agent, was first isolated from the extract of the bark of Taxus brevifolia Nutt., which is potentially a limited source for Taxol. In the search of an alternative source, optimum and cost benefit extracting solvents, various solvents with different percentage were utilized to extract Taxol from needles of Taxus baccata. "nMethods: One g of the dried needles of Taxus baccata, collected from Torkaman and Noor cities of Iran, was extracted with pure ethanol or acetone and 50% and 20% of ethanol or acetone in water. Solvents were evaporated to dryness and the residues were dissolved in 5 ml of methanol and filtered. To one ml of the filtrate was added 50 μl of cinamyl acetate as the internal standard and 20 μl of the resulting solution was subjected to the HPLC to determine the extraction efficiencies of tested solvents. Five μl of filtrate was also subjected to the LC-MS using water/acetonitrile (10/90 as mobile phase and applying positive electrospray ionization (ESI to identify the authenticity of Taxol. "nResults: Results of this study indicated that Taxol extraction efficiency was enhanced as the percentage of ethanol or acetone was increased. HPLC analysis showed that Taxol could be quantified by UV detection using standard curve. The standard curve covering the concentration ranges of 7.8 - 500 μg/ml was linear (r2= 0.9992 and CV% ranged from 0.52 to 15.36. LC-MS analysis using ESI in positive-ion mode confirmed the authenticity of Taxol (m/z 854; M+H, as well as some adduct ions such as M+Na (m/z 876, M+K (m/z 892 and M+CH3CN+H2O (m/z 913. "nConclusions: The results suggest that 100% acetone is the best solvent for the extraction of Taxol from Taxus baccata needles.

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

Energy Technology Data Exchange (ETDEWEB)

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

1999-03-01

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

Validation of HPLC-ESI-MS/MS Protocol to Analyze EtG in Hair for Assessment of Chronic Excessive Alcohol Use in Thailand in Conjunction with AUDIT.

Science.gov (United States)

Thananchai, Thiwaphorn; Junkuy, Anongphan; Kittirattanapaiboon, Phunnapa; Sribanditmongkol, Pongruk

2016-06-01

Hair analysis for chronic excessive alcohol (ethanol) use has focused on ethyl glucuronide (EtG), a minor metabolite of ethanol. Preferred methods have involved high-performance liquid chromatography (HPLC) combined with tandem mass spectrometry (MS/MS) in line with an electrospray ionization (ESI) source. EtG analysis in hair has not yet been introduced to Thailand To validate an in-house HPLC-ESI-MS/MS hair analysis protocol for EtG and to apply it to a field sample of alcohol drinkers to assess different risk levels of alcohol consumption as measured by the Alcohol Use Disorders Identification Test (AUDIT). Validation procedures followed guidelines of the US Food and Drug Administration, the European Medicines Agency, and the Scientific Working Group for Forensic Toxicology. One hundred twenty subjects reported consuming alcohol during a 3-month period prior to enrollment. After taking the Thai-language version of AUDIT, subjects were divided on the basis of test scores into low, medium, and high-risk groups for chronic excessive alcohol use. The protocol satisfied the international standards for selectivity, specificity, accuracy, precision, and calibration curve. There was no significant matrix effect. Limits of detection and quantification (LOD/LOQ) were set at 15 pg of EtG per mg of hair. The protocol was not able to detect EtG in low-risk subjects (n = 38). Detection rates for medium-risk (n = 42) and high-risk subjects (n = 40) were 14.3% and 85%, respectively. The median of EtG concentration between these two groups were significantly different. Sensitivity and specificity were both more than 90% when EtG concentrations of high-risk subjects were compared with the 30 pg/mg cutoff recommended by the Society of Hair Testing (SoHT) for diagnosing chronic excessive alcohol consumption, based on an average ethanol daily intake greater than 60 g. The in-house protocol for EtG analysis in hair was validated according to international standards. The protocol is a

Screening of Satureja subspicata Vis. Honey by HPLC-DAD, GC-FID/MS and UV/VIS: Prephenate Derivatives as Biomarkers.

Science.gov (United States)

Jerković, Igor; Kranjac, Marina; Marijanović, Zvonimir; Zekić, Marina; Radonić, Ani; Tuberoso, Carlo Ignazio Giovanni

2016-03-21

The samples of Satureja subspicata Vis. honey were confirmed to be unifloral by melissopalynological analysis with the characteristic pollen share from 36% to 71%. Bioprospecting of the samples was performed by HPLC-DAD, GC-FID/MS, and UV/VIS. Prephenate derivatives were shown to be dominant by the HPLC-DAD analysis, particularly phenylalanine (167.8 mg/kg) and methyl syringate (MSYR, 114.1 mg/kg), followed by tyrosine and benzoic acid. Higher amounts of MSYR (3-4 times) can be pointed out for distinguishing S. subspicata Vis. honey from other Satureja spp. honey types. GC-FID/MS analysis of ultrasonic solvent extracts of the samples revealed MSYR (46.68%, solvent pentane/Et2O 1:2 (v/v); 52.98%, solvent CH2Cl2) and minor abundance of other volatile prephenate derivatives, as well as higher aliphatic compounds characteristic of the comb environment. Two combined extracts (according to the solvents) of all samples were evaluated for their antioxidant properties by FRAP and DPPH assay; the combined extracts demonstrated higher activity (at lower concentrations) in comparison with the average honey sample. UV/VIS analysis of the samples was applied for determination of CIE Lab colour coordinates, total phenolics (425.38 mg GAE/kg), and antioxidant properties (4.26 mmol Fe(2+)/kg (FRAP assay) and 0.8 mmol TEAC/kg (DDPH assay)).

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

Science.gov (United States)

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

2017-01-01

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

Determination of morphine, codeine and 6-monoacetylmorphine in saliva of substance-abuse patients using HPLC/MS methods

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Milovanović Vesna

2012-01-01

Full Text Available Background/Aim. Saliva represents an alternative specimen for substances abuse determination in toxicology. Hence, the aim of this study was to optimize a method for saliva specimen preparation for heroin metabolites, morphine and 6-monoacetylmorphine (6-mam, and codeine determination by liquid chromatography-mass spectrometry (LC/MS, and to apply this method on saliva samples taken from the patients. Methods. Saliva specimen was prepared using liqiud/liquid extraction of morphine, codeine and 6- mam by mixture of chloroform and isopropanol (9 : 1; v/v. Extracts were analysed by HPLC/MS technique: separation column Waters Spherisorb® 5 μm, ODS2, 4.6 × 100 mm; mobile phase: ammonium acetate : acetonitile (80 : 20; v/v, mobile phase flow rate 0.3 mL/min; mass detection range: 100-400 m/z. Regression and correlation analyses were performed with the probalility level of 0.05. Concentrations of morphine, codeine and 6-mam were determined in saliva samples of the patients with “opiates” in urine identified by the test strips. Results. Calibration for each analysed substance was done in the concentration range from 0.1 to 1 mg/L and the coefficient of correlation was R2 > 0.99. We obtained following calibration curves: y = 385531x + 14584; y = 398036x + 31542; and y = 524162x - 27105, for morphine, codeine and 6-mam, respectively. Recovery for morphine and codeine determination was 99%, while for 6- mam it was 94%. Limits of detection and quantification of a proposed method were 0.01 mg/L and 0.05 mg/L, respectively. Concentration of morphine in the saliva of the heroin users ranged between 0.54 and 5.82 mg/L, concentration of codeine between 0.05 and 5.33, and 6-mam between 0.01 and 0.68 mg/L. A statistically significant correlation between codeine and 6-mam concentrations was obtained. Conclusion. A proposed HPLC/MS method for morphine, codeine and 6-mam determination in saliva is accurate, simple, cheap and suitable for routine analysis and

Routine low-level monitoring of polar pesticides and pesticide degradates by HPLC/ESI-MS: Evaluating long-term performance

Science.gov (United States)

Furlong, E.T.; Martin, Jeffrey D.; Werner, S.L.; Gates, Paul M.

2002-01-01

The sensitivity and selective determination of polar pesticides were analyzed using high-performance liquid chromatography/electrospray ionization-mass spectrometry (HPLC/ESI-MS). The effects of multiple operators and instruments on method performance were evaluated using 440 pairs of fortified reagent-water and blank reagent-water samples. The influence of varying environmental matrices on recovery and precision were also analyzed using 200 fortified ambient water samples and duplicate ambient water samples. The results show that compound stability in filtered water was matrix-, chemical class- and compound-dependent which ranged from 1 day to 2 weeks.

HPLC, NMR and MALDI-TOF MS Analysis of Condensed Tannins from Lithocarpus glaber Leaves with Potent Free Radical Scavenging Activity

OpenAIRE

Zhang, Liang Liang; Lin, Yi Ming

2008-01-01

Using acid-catalyzed degradation in the presence of cysteamine, the condensed tannins from Lithocarpus glaber leaves were characterized, following thiolysis, by means of reversed-phase HPLC, 13C-NMR and matrix-assisted laser desorption/ionization time of flight mass spectrometry (MALDI-TOF MS) analyses. The thiolysis reaction products showed the presence of the procyanidin (PC) and prodelphinidin (PD) structures. The 13C-NMR spectrum revealed that the condensed tannins were comprised of PD (7...

HPLC-DAD-ESI/MS identification of light harvesting and light screening pigments in the lake sediments at Edmonson Point.

Science.gov (United States)

Giovannetti, Rita; Alibabaei, Leila; Zannotti, Marco; Ferraro, Stefano; Petetta, Laura

2013-01-01

The composition of sedimentary pigments in the Antarctic lake at Edmonson Point has been investigated and compared with the aim to provide a useful analytical method for pigments separation and identification, providing reference data for future assessment of possible changes in environmental conditions. Reversed phase high performance liquid chromatography (HPLC) with electrospray-mass spectrometry (ESI-MS) detection and diode array detection (DAD) has been used to identify light screening and light harvesting pigments. The results are discussed in terms of local environmental conditions.

RP-HPLC-DAD-ESI-QTOF-MS based metabolic profiling of the potential Olea europaea by-product "wood" and its comparison with leaf counterpart.

Science.gov (United States)

Ammar, Sonda; Contreras, Maria Del Mar; Gargouri, Boutheina; Segura-Carretero, Antonio; Bouaziz, Mohamed

2017-05-01

Olea europaea L. organs such as leaves, stems and roots have been associated with numerous in vivo and in vitro biological activities and used for traditional medicinal purposes. However, tree wood is an untapped resource with little information about their chemical composition. That is why, the objective of this study is to increase the knowledge about phytochemicals from 'Chemlali' olive wood by means of mass spectrometry-based analyses. Its comparison with by-products derived from leaves was also studied. Hydromethanol extracts from wood and leaves with stems of 'Chemlali' olive cultivar were analysed using reversed-phase (RP) high-performance liquid chromatography (HPLC) coupled to two detection systems: diode-array detection (DAD) and quadrupole time-of-flight (QTOF) mass spectrometry (MS) in negative ion mode. Tandem MS experiments were performed to establish the chemical structure of olive phytochemicals. A total of 85 compounds were characterised in the studied olive parts and classified as: sugars (3), organic acids (5), one phenolic aldehyde, simple phenolic acids (6), simple phenylethanoids (5), flavonoids (14), coumarins (3), caffeoyl phenylethanoid derivatives (6), iridoids (5), secoiridoids (32), and lignans (5). To our knowledge, the major part of these metabolites was not previously reported in olive tree wood, and 10 olive chemical constituents were identified for the first time in the Oleaceae family. The results presented here demonstrated the usefulness of the methodology proposed, based on RP-HPLC-DAD-ESI-QTOF-MS and MS/MS, to develop an exhaustive metabolic profiling and to recover new biologically active compounds in olive wood with pharmacologic and cosmetic potential. Copyright © 2017 John Wiley & Sons, Ltd. Copyright © 2017 John Wiley & Sons, Ltd.

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

DEFF Research Database (Denmark)

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

2014-01-01

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

Pharmacokinetics of taurolidine following repeated intravenous infusions measured by HPLC-ESI-MS/MS of the derivatives taurultame and taurinamide in glioblastoma patients.

Science.gov (United States)

Stendel, Ruediger; Scheurer, Louis; Schlatterer, Kathrin; Stalder, Urs; Pfirrmann, Rolf W; Fiss, Ingo; Möhler, Hanns; Bigler, Laurent

2007-01-01

Taurolidine is known to have antimicrobial activity. Furthermore, at lower concentrations, it has been found to exert a selective antineoplastic effect in vitro and in vivo. The aim of this study was to investigate the pharmacokinetics of taurolidine in vivo following repeated intravenous infusion in a schedule used for the treatment of glioblastoma. As a prerequisite, the pharmacokinetics of taurolidine in human blood plasma and whole blood in vitro was investigated. The pharmacokinetics of taurolidine and its derivatives taurultame and taurinamide were investigated in human blood plasma and in whole blood in vitro using blood from a healthy male volunteer. During repeated intravenous infusion therapy with taurolidine, plasma samples were taken every hour for a period of 13 hours per day in seven patients (three male, four female; mean age 48.4 +/- 12.8 years, range 27-66 years) with a glioblastoma. Following dansyl derivatisation, the concentrations of taurultame and taurinamide were determined using a new method based on high-performance liquid chromatography (HPLC) online coupled to electrospray ionisation tandem mass spectrometry (ESI-MS/MS) in the multiple reaction monitoring mode. Under the experimental conditions used, taurolidine could not be determined directly and was back-calculated from the taurultame and taurinamide values. The new HPLC-ESI-MS/MS method demonstrated high accuracy and reproducibility. In vitro plasma concentrations of taurultame and taurinamide remained constant over the incubation period. In whole blood in vitro, a time-dependent formation of taurinamide was observed. At the start of the incubation, the taurultame-taurinamide ratio (TTR) was 0.95 at an initial taurolidine concentration of 50 microg/mL, and 1.69 at 100 microg/mL. The concentration of taurultame decreased at the same rate as the taurinamide concentration increased, showing logarithmic kinetics. The calculated taurolidine concentration remained largely constant over the

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

International Nuclear Information System (INIS)

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

2000-01-01

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

Gc-ms, hplc profiling, antioxidant, antimicrobial and cytotoxicity studies of malcolmia africana leaves

International Nuclear Information System (INIS)

Bokhari, T.H.; Rasool, N.; Riaz, M.; Riaz, M.

2014-01-01

Plants are known to be the richest source of natural antioxidant and antimicrobial properties. The use of herbs and medicinal plants as the first medicines is a universal phenomenon. The present study was carried out to examine the antioxidant, antimicrobial and cytotoxicity potential Malcolmia africana leaves extract, fraction, essential oil and fixed oil. The whole plant was extracted with absolute methanol and further fractionated with increasing polarity based absolute solvents. Different fractions were taken by solvent extraction method and their antimicrobial activities were determined. The IC50 and % inhibition by linoleic acid oxidation was evaluated for the antioxidant studies. The cytotoxicity of the plant extract and fractions were assayed against human blood erythrocytes (RBCs). The DPPH scavenging and linoleic acid oxidation assays were carried out. Qualitative and quantitative analysis of secondary metabolites was also carried out. The presence of phenolics was also studied by HPLC. The GC-MS analysis of Malcolmia africana essential oil and fixed oil was also carried out. (author)

HPLC-DAD-ESI/MS Identification of Light Harvesting and Light Screening Pigments in the Lake Sediments at Edmonson Point

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Rita Giovannetti

2013-01-01

Full Text Available The composition of sedimentary pigments in the Antarctic lake at Edmonson Point has been investigated and compared with the aim to provide a useful analytical method for pigments separation and identification, providing reference data for future assessment of possible changes in environmental conditions. Reversed phase high performance liquid chromatography (HPLC with electrospray-mass spectrometry (ESI-MS detection and diode array detection (DAD has been used to identify light screening and light harvesting pigments. The results are discussed in terms of local environmental conditions.

HPLC-DAD-ESI-MS Analysis of Flavonoids from Leaves of Different Cultivars of Sweet Osmanthus.

Science.gov (United States)

Wang, Yiguang; Fu, Jianxin; Zhang, Chao; Zhao, Hongbo

2016-09-14

Osmanthus fragrans Lour. has traditionally been a popular ornamental plant in China. In this study, ethanol extracts of the leaves of four cultivar groups of O. fragrans were analyzed by high-performance liquid chromatography coupled with diode array detection (HPLC-DAD) and high-performance liquid chromatography with electrospray ionization and mass spectrometry (HPLC-ESI-MS). The results suggest that variation in flavonoids among O. fragrans cultivars is quantitative, rather than qualitative. Fifteen components were detected and separated, among which, the structures of 11 flavonoids and two coumarins were identified or tentatively identified. According to principal component analysis (PCA) and hierarchical cluster analysis (HCA) based on the abundance of these components (expressed as rutin equivalents), 22 selected cultivars were classified into four clusters. The seven cultivars from Cluster III ('Xiaoye Sugui', 'Boye Jingui', 'Wuyi Dangui', 'Yingye Dangui', 'Danzhuang', 'Foding Zhu', and 'Tianxiang Taige'), which are enriched in rutin and total flavonoids, and 'Sijigui' from Cluster II which contained the highest amounts of kaempferol glycosides and apigenin 7-O-glucoside, could be selected as potential pharmaceutical resources. However, the chemotaxonomy in this paper does not correlate with the distribution of the existing cultivar groups, demonstrating that the distribution of flavonoids in O. fragrans leaves does not provide an effective means of classification for O. fragrans cultivars based on flower color.

Optimization of Ultrasound-Assisted Extraction, HPLC and UHPLC-ESI-Q-TOF-MS/MS Analysis of Main Macamides and Macaenes from Maca (Cultivars of Lepidium meyenii Walp

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Shu-Xiao Chen

2017-12-01

Full Text Available Ultrasound-assisted extraction (UAE, using petroleum ether as the solvent, was systematically applied to extract main macamides and macaenes from Maca hypocotyls. Extraction yield was related with four variables, including ratio of solution to solid, extraction temperature, extraction time, and extraction power. On the basis of response surface methodology (RSM, the optimal conditions were determined to be the ratio of solution to solid as 10:1 (mL/g, the extraction temperature of 40 °C, the extraction time of 30 min, and the extraction power of 200 W. Based on the optimal extraction method of UAE, the total contents of ten main macamides and two main macaenes of Maca cultivated in twenty different areas of Tibet were analyzed by HPLC and UHPLC-ESI-Q-TOF-MS/MS. This study indicated that UAE was able to effectively extract macamides alkaloids from Maca hypocotyls. Quantitative analysis showed that geographical origins, not ecotypes, played a more important role on the accumulation of active macamides in Maca.

Optimization of Ultrasound-Assisted Extraction, HPLC and UHPLC-ESI-Q-TOF-MS/MS Analysis of Main Macamides and Macaenes from Maca (Cultivars of Lepidium meyenii Walp).

Science.gov (United States)

Chen, Shu-Xiao; Li, Ke-Ke; Pubu, Duoji; Jiang, Si-Ping; Chen, Bin; Chen, Li-Rong; Yang, Zhen; Ma, Chao; Gong, Xiao-Jie

2017-12-10

Ultrasound-assisted extraction (UAE), using petroleum ether as the solvent, was systematically applied to extract main macamides and macaenes from Maca hypocotyls. Extraction yield was related with four variables, including ratio of solution to solid, extraction temperature, extraction time, and extraction power. On the basis of response surface methodology (RSM), the optimal conditions were determined to be the ratio of solution to solid as 10:1 (mL/g), the extraction temperature of 40 °C, the extraction time of 30 min, and the extraction power of 200 W. Based on the optimal extraction method of UAE, the total contents of ten main macamides and two main macaenes of Maca cultivated in twenty different areas of Tibet were analyzed by HPLC and UHPLC-ESI-Q-TOF-MS/MS. This study indicated that UAE was able to effectively extract macamides alkaloids from Maca hypocotyls. Quantitative analysis showed that geographical origins, not ecotypes, played a more important role on the accumulation of active macamides in Maca.

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

International Nuclear Information System (INIS)

Goessler, W.

1997-07-01

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

Specific determination of clinical and toxicological important substances in biological samples by LC-MS

International Nuclear Information System (INIS)

Mitulovic, G.

2001-02-01

This thesis of this dissertation is the specific determination of clinical and toxicological important substances in biological samples by LC-MS. Nicotine was determined in serum after application of nicotine plaster and nicotine nasal spray with HPLC-ESI-MS. Cotinine was determined direct in urine with HPLC-ESI-MS. Short time anesthetics were determined in blood and cytostatics were determined in liquor with HPLC-ESI-MS. (botek)

Comprehensive analysis of proteins of pH fractionated samples using monolithic LC/MS/MS, intact MW measurement and MALDI-QIT-TOF MS

Science.gov (United States)

Yoo, Chul; Patwa, Tasneem H.; Kreunin, Paweena; Miller, Fred R.; Huber, Christian G.; Nesvizhskii, Alexey I.; Lubman, David M.

2012-01-01

A comprehensive platform that integrates information from the protein and peptide levels by combining various MS techniques has been employed for the analysis of proteins in fully malignant human breast cancer cells. The cell lysates were subjected to chromatofocusing fractionation, followed by tryptic digestion of pH fractions for on-line monolithic RP-HPLC interfaced with linear ion trap MS analysis for rapid protein identification. This unique approach of direct analysis of pH fractions resulted in the identification of large numbers of proteins from several selected pH fractions, in which approximately 1.5 μg of each of the pH fraction digests was consumed for an analysis time of ca 50 min. In order to combine valuable information retained at the protein level with the protein identifications obtained from the peptide level information, the same pH fraction was analyzed using nonporous (NPS)-RP-HPLC/ESI-TOF MS to obtain intact protein MW measurements. In order to further validate the protein identification procedures from the fraction digest analysis, NPS-RP-HPLC separation was performed for off-line protein collection to closely examine each protein using MALDI-TOF MS and MALDI-quadrupole ion trap (QIT)-TOF MS, and excellent agreement of protein identifications was consistently observed. It was also observed that the comparison to intact MW and other MS information was particularly useful for analyzing proteins whose identifications were suggested by one sequenced peptide from fraction digest analysis. PMID:17206599

Quickly Screening for Potential α-Glucosidase Inhibitors from Guava Leaves Tea by Bioaffinity Ultrafiltration Coupled with HPLC-ESI-TOF/MS Method.

Science.gov (United States)

Wang, Lu; Liu, Yufeng; Luo, You; Huang, Kuiying; Wu, Zhenqiang

2018-02-14

Guava leaves tea (GLT) has a potential antihyperglycemic effect. Nevertheless, it is unclear which compound plays a key role in reducing blood sugar. In this study, GLT extract (IC 50 = 19.37 ± 0.21 μg/mL) exhibited a stronger inhibitory potency against α-glucosidase than did acarbose (positive control) at IC 50 = 178.52 ± 1.37 μg/mL. To rapidly identify the specific α-glucosidase inhibitor components from GLT, an approach based on bioaffinity ultrafiltration combined with high performance liquid chromatography coupled to electrospray ionization-time-of-flight-mass spectrometry (BAUF-HPLC-ESI-TOF/MS) was developed. Under the optimal bioaffinity ultrafiltration conditions, 11 corresponding potential α-glucosidase inhibitors with high affinity degrees (ADs) were screened and identified from the GLT extract. Quercetin (IC 50 = 4.51 ± 0.71 μg/mL) and procyanidin B3 (IC 50 = 28.67 ± 5.81 μg/mL) were determined to be primarily responsible for the antihyperglycemic effect, which further verified the established screening method. Moreover, structure-activity relationships were discussed. In conclusion, the BAUF-HPLC-ESI-TOF/MS method could be applied to determine the potential α-glucosidase inhibitors from complex natural products quickly.

HPLC-DAD-ESI/MS(n) analysis of phenolic compounds for quality control of Grindelia robusta Nutt. and bioactivities.

Science.gov (United States)

Ferreres, Federico; Grosso, Clara; Gil-Izquierdo, Angel; Valentão, Patrícia; Azevedo, Carolina; Andrade, Paula B

2014-06-01

The phenolic composition of herbal tea (HT) and hydromethanolic extract (HME) obtained from Grindelia robusta Nutt. was studied by HPLC-DAD-ESI/MS(n). Thirty six flavonoids and hydroxycinnamic acids were detected, from which thirty are described for the first time in this species. Quantification by HPLC-DAD showed that diosmetin-7-O-glucuronide-3'-O-pentoside+apigenin-7-O-glucuronide-4'-O-pentoside, apigenin-7-O-glucuronide+diosmetin-7-O-glucuronide and 3,5-dicaffeoylquinic acid+3,4-dicaffeoylquinic acid were the major compounds. Since the health-promoting effects of natural phenolic compounds against brain disorders is of increasing interest, HT and HME were also tested against oxygen and nitrogen reactive species and against enzymes related with Alzheimer's disease and depression. Extracts displayed strong in vitro scavenging activity and monoamine oxidase-A (MAO-A) inhibitory activity. The anti-MAO-A capacity was observed at non-toxic concentrations for SH-SY5Y human neuroblastoma cell line, reinforcing the benefits of G. robusta HT. However, no protection against hydrogen peroxide treatment was observed. Copyright © 2014 Elsevier B.V. All rights reserved.

Profiling of dehydropyrrolizidine alkaloids and their N-oxides in herbarium-preserved specimens of amsinckia species using HPLC-esi(+)MS.

Science.gov (United States)

Colegate, Steven M; Welsh, Stanley L; Gardner, Dale R; Betz, Joseph M; Panter, Kip E

2014-07-30

Species of the Amsinckia genus (Boraginaceae) are known to produce potentially hepato-, pneumo-, and/or genotoxic dehydropyrrolizidine alkaloids. However, the taxonomic differentiation of Amsinckia species can be very subtle and there seems to be marked differences in toxicity toward grazing livestock. Methanol extracts of mass-limited leaf samples from herbarium specimens (collected from 1899 to 2013) of 10 Amsinckia species and one variety were analyzed using HPLC-esi(+)MS and MS/MS for the presence of potentially toxic dehydropyrrolizidine alkaloids and/or their N-oxides. Dehydropyrrolizidine alkaloids were detected in all specimens examined ranging from about 1 to 4000 μg/g of plant. Usually occurring mainly as their N-oxides, the predominant alkaloids were the epimeric lycopsamine and intermedine. Also sometimes observed in higher concentrations were the 3'- and 7-acetyl derivatives of lycopsamine/intermedine and their N-oxides. Within a designated species, an inconsistent profile was often observed that may be due to natural variation, taxonomic misassignment, or nonuniform degradation due to plant collection and storage differences.

Contaminant screening of wastewater with HPLC-IM-qTOF-MS and LC+LC-IM-qTOF-MS using a CCS database.

Science.gov (United States)

Stephan, Susanne; Hippler, Joerg; Köhler, Timo; Deeb, Ahmad A; Schmidt, Torsten C; Schmitz, Oliver J

2016-09-01

Non-target analysis has become an important tool in the field of water analysis since a broad variety of pollutants from different sources are released to the water cycle. For identification of compounds in such complex samples, liquid chromatography coupled to high resolution mass spectrometry are often used. The introduction of ion mobility spectrometry provides an additional separation dimension and allows determining collision cross sections (CCS) of the analytes as a further physicochemical constant supporting the identification. A CCS database with more than 500 standard substances including drug-like compounds and pesticides was used for CCS data base search in this work. A non-target analysis of a wastewater sample was initially performed with high performance liquid chromatography (HPLC) coupled to an ion mobility-quadrupole-time of flight mass spectrometer (IM-qTOF-MS). A database search including exact mass (±5 ppm) and CCS (±1 %) delivered 22 different compounds. Furthermore, the same sample was analyzed with a two-dimensional LC method, called LC+LC, developed in our group for the coupling to IM-qTOF-MS. This four dimensional separation platform revealed 53 different compounds, identified over exact mass and CCS, in the examined wastewater sample. It is demonstrated that the CCS database can also help to distinguish between isobaric structures exemplified for cyclophosphamide and ifosfamide. Graphical Abstract Scheme of sample analysis and database screening.

LC-MS characterization of valsartan degradation products and comparison with LC-PDA

Directory of Open Access Journals (Sweden)

Sumaia Araújo Pires

2015-12-01

Full Text Available abstract Valsartan was submitted to forced degradation under acid hydrolysis condition as prescribed by the ICH. Degraded sample aliquots were separated via HPLC using a Hypersil ODS (C18 column (250 x 4.6 mm i.d., 5 µm. Either photodiode array (PDA detection or mass spectrometry (MS full scan monitoring of HPLC runs were used. HPLC-PDA failed to indicate Valsartan degradation under forced acid degradation, showing an insignificant peak area variation and that Valsartan apparently remained pure. HPLC-MS using electrospray ionization (ESI and total ionic current (TIC monitoring did not reveal any peak variation either, but inspection of the ESI mass spectra showed the appearance of m/z 306 and m/z 352 ions for the same retention time as that of Valsartan (m/z 436. These ions were identified as being protonated molecules of two co-eluting degradation products formed by hydrolysis. These assignments were confirmed by ESI-MS/MS with direct infusion of the degraded samples. The results showed that the use of selective HPLC-MS is essential for monitoring Valsartan degradation. Efficient HPLC separation coupled to selective and structural diagnostic MS monitoring seems therefore mandatory for comprehensive drug degradation studies, particularly for new drugs and formulations, and for method development.

Analytical Method Details (MS): SE52_MS01 [Metabolonote[Archive

Lifescience Database Archive (English)

Full Text Available stem and Waters Q-Tof Premier UPLC-QTOF-MS ESI Negative The eluates (3 μl) were subsequently subjected to metabolome...DS column (LC-ESI-Q-Tof/MS, HPLC: Waters Acquity UPLC system; MS: Waters Q-Tof Premier). The metabolome...d (Matsuda et al., 2009c, 2010a). Briefly, the metabolome data were obtained in the negative ion mode (m/z 1... the complex nature of the metabolome data. To construct MS2T libraries, the extracts of five ecotypes were

Determination and identification of hydrophilic and hydrophobic arsenic species in methanol extract of fresh cod liver by RP-HPLC with simultaneous ICP-MS and ESI-Q-TOF-MS detection.

Science.gov (United States)

Arroyo-Abad, Uriel; Lischka, Susanne; Piechotta, Christian; Mattusch, Jürgen; Reemtsma, Thorsten

2013-12-01

The present study was focused on the determination and identification of arsenic species in methanolic extracts of cod liver. Arsenic species were fractionated and the fractions analysed by RP-HPLC-ICP-MS coupled with ESI-Q-TOF-MS. The total concentration of arsenic in the fresh cod liver was analysed by ICP-MS to be 1.53±0.02 mg As kg(-1)w.w. and the extraction recovery was ca. 100% and the column recovery >93%. Besides polar inorganic and methylated arsenic species (>70%) more hydrophobic arsenic-containing fatty acids and hydrocarbons occurred. Based on the mass spectrometric data proposals for molecular structures were elaborated for 20 of the organic As species included 10 arsenic-containing fatty acids (AsFA) and an arsenic-containing hydrocarbon (AsHC) mentioned for the first time in fresh cod liver. Arsenobetaine was found as main water-soluble arsenic compound in cod liver followed by higher molecular mass arsenic-containing fatty acids and hydrocarbons. Copyright © 2013 Elsevier Ltd. All rights reserved.

α-Glucosidase inhibition and antioxidant activity of an oenological commercial tannin. Extraction, fractionation and analysis by HPLC/ESI-MS/MS and (1)H NMR.

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Muccilli, Vera; Cardullo, Nunzio; Spatafora, Carmela; Cunsolo, Vincenzo; Tringali, Corrado

2017-01-15

Two batches of the oenological tannin Tan'Activ R, (toasted oak wood - Quercus robur), were extracted with ethanol. A fractionation on XAD-16 afforded four fractions for each extract. Extracts and fractions were evaluated for antioxidant activity (DPPH), polyphenol content (GAE) and yeast α-glucosidase inhibitory activity. Comparable results were obtained for both columns, fractions X1B and X2B showing the highest antioxidant activity. Fractions X1C and X2C notably inhibited α-glucosidase, with IC50=9.89 and 8.05μg/mL, respectively. Fractions were subjected to HPLC/ESI-MS/MS and (1)H NMR analysis. The main phenolic constituents of both X1B and X2B were a monogalloylglucose isomer (1), a HHDP-glucose isomer (2), castalin (3) gallic acid (4), vescalagin (5), and grandinin (or its isomer roburin E, 6). X1C and X2C showed a complex composition, including non-phenolic constituents. Fractionation of X2C gave a subfraction, with enhanced α-glucosidase inhibitory activity (IC50=6.15μg/mL), with castalagin (7) as the main constituent. Copyright © 2016 Elsevier Ltd. All rights reserved.

Simultaneous determination of phenolic acids and flavonoids in Chenopodium formosanum Koidz. (djulis) by HPLC-DAD-ESI-MS/MS.

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Hsu, B Y; Lin, S W; Inbaraj, B Stephen; Chen, B H

2017-01-05

A high performance liquid chromatography-diode array detection-tandem mass spectrometry method (HPLC-DAD-MS/MS) was developed for simultaneous determination of phenolic acids and flavonoids in djulis (Chenopodium formosanum Koidz.), a traditional Chinese herb reported to possess vital biological activities. A high yield of phenolic acids and flavonoids was attained by employing 50% ethanol in water as the extraction solvent and shaking in a 60°C water bath for 3h. A total of 8 phenolic acids and 14 flavonoids were separated and identified within 55min by using a Poroshell 120 EC-C18 column with detection at 280nm, flow rate at 0.8mL/min, column temperature at 35°C, and a gradient solvent system of 0.1% formic acid in water and acetonitrile. Two internal standards caffeic acid and kaempferol-3-O-rutinoside were used for quantitation of phenolic acids and flavonoids in djulis respectively. The amounts of phenolic acids ranged from 11.5±0.8μg/g (caffeoyl-putrescine-derivative (2)) to 1855.3±16.9μg/g (hydroxylphenylacetic acid pentoside), while the flavonoids ranged from 19.93±2.29μg/g (quercetin-3-O-(coumaryl)-rutinoside-pentoside (1)) to 257.3±2.05μg/g (rutin-O-pentoside (2)). A high recovery (89.68-97.20%) and high reproducibility was obtained for both phenolic acids and flavonoids with the relative standard deviation (RSD) for the latter ranging from 0.09-8.22% (intra-day variability) and 0.80-8.48% (inter-day variability). This method may be applied to determination of both phenolic acids and flavonoids in food products and Chinese herbs. Copyright © 2016 Elsevier B.V. All rights reserved.

Nonylphenol Toxicity Evaluation and Discovery of Biomarkers in Rat Urine by a Metabolomics Strategy through HPLC-QTOF-MS

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Yan-Xin Zhang

2016-05-01

Full Text Available Nonylphenol (NP was quantified using liquid chromatography tandem mass spectrometry (LC-MS/MS in the urine and plasma of rats treated with 0, 50, and 250 mg/kg/day of NP for four consecutive days. A urinary metabolomic strategy was originally implemented by high performance liquid chromatography time of flight mass spectrometry (HPLC-QTOF-MS to explore the toxicological effects of NP and determine the overall alterations in the metabolite profiles so as to find potential biomarkers. It is essential to point out that from the observation, the metabolic data were clearly clustered and separated for the three groups. To further identify differentiated metabolites, multivariate analysis, including principal component analysis (PCA, orthogonal partial least-squares discriminant analysis (OPLS-DA, high-resolution MS/MS analysis, as well as searches of Metlin and Massbank databases, were conducted on a series of metabolites between the control and dose groups. Finally, five metabolites, including glycine, glycerophosphocholine, 5-hydroxytryptamine, malonaldehyde (showing an upward trend, and tryptophan (showing a downward trend, were identified as the potential urinary biomarkers of NP-induced toxicity. In order to validate the reliability of these potential biomarkers, an independent validation was performed by using the multiple reaction monitoring (MRM-based targeted approach. The oxidative stress reflected by urinary 8-oxo-deoxyguanosine (8-oxodG levels was elevated in individuals highly exposed to NP, supporting the hypothesis that mitochondrial dysfunction was a result of xenoestrogen accumulation. This study reveals a promising approach to find biomarkers to assist researchers in monitoring NP.

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

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

2015-01-01

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

Fast gradient HPLC/MS separation of phenolics in green tea to monitor their degradation.

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Šilarová, Petra; Česlová, Lenka; Meloun, Milan

2017-12-15

The degradation of catechins and other phenolics in green tea infusions were monitored using fast HPLC/MS separation. The final separation was performed within 2.5min using Ascentis Express C18 column (50mm×2.1mm i.d.) packed with 2μm porous shell particles. Degradation was studied in relation to the temperature of water (70, 80, 90°C) and the standing time of the infusion (up to 6h). Along with chromatographic separation, the antioxidant properties of the infusions were monitored using two spectrophotometric methods. During staying of green tea infusion, the degradation of some catechins probably to gallic acid was observed. Finally, the influence of tea bag storage on antioxidant properties of green tea was evaluated. Rapid degradation of antioxidants after 3weeks was observed. The principal component analysis, factor analysis and discriminant analysis were used for the statistical evaluation of obtained experimental data. Copyright © 2017 Elsevier Ltd. All rights reserved.

Characterization and quantification of flavonoids and organic acids over fruit development in American cranberry (Vaccinium macrocarpon) cultivars using HPLC and APCI-MS/MS.

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Wang, Yifei; Johnson-Cicalese, Jennifer; Singh, Ajay P; Vorsa, Nicholi

2017-09-01

Cranberry flavonoids, including anthocyanins, flavonol glycosides and proanthocyanidins, and organic acids were characterized and quantified by HPLC and LC-MS/MS during fruit development and ripening in eight cranberry cultivars. Anthocyanin biosynthesis initiated at early fruit development and reached highest level in mature fruit, with significant differences between cultivars. Major flavonol glycosides, including the most abundant quercetin-3-galactoside and myricetin-3-galactoside, showed consistent concentrations during the season with moderate fluctuation, and were at similar levels in mature fruits of the eight cultivars. Proanthocyanidins declined during fruit development and then increased slightly in later maturation stages. Levels of various proanthocyanidin oligomers/polymers with different degree-of-polymerization were highly correlated within a cultivar during fruit development. Cultivars with coancestry exhibited similar levels (high/low) of anthocyanins or proanthocyanidins, indicating genetic effects on biosynthesis of such flavonoids. All cultivars showed similar levels of malic and citric acids, and declining levels of quinic acid during fruit development. Benzoic acid was extremely low early in the season and increased sharply during fruit ripening. Levels of quinic and citric acids were significantly different among cultivars in the mature fruit. Concentrations of proanthocyanidins, anthocyanins, quinic acid and benzoic acid have a strong developmental association in developing ovaries. Copyright © 2017 Elsevier B.V. All rights reserved.

Simultaneous Determination and Pharmacokinetic Study of Six Components in Rat Plasma by HPLC-MS/MS after Oral Administration of Acanthopanax sessiliflorus Fruit Extract

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Peng Du

2016-12-01

Full Text Available A specific and reliable HPLC-MS/MS method was developed and validated for the simultaneous determination of protocatechuic acid (PCA, scopolin, (−-pinoresinol-4,4′-di-O-β-d-glucopyranoside (PDG, acanthoside D, acanthoside B and hyperin in rat plasma for the first time. The analytes were separated on a C18 column (50 × 2.1 mm, 1.8 µm and a triple-quadrupole mass spectrometer equipped with an electrospray ionization (ESI source was used for detection. The rat plasma sample was prepared using the protein precipitation procedure. The calibration curves were linear over a concentration range of 1.2–1200.0 ng/mL for PCA, 0.96–960.0 ng/mL for scopolin, 1.12–1120.0 ng/mL for PDG, 1.32–1320.0 ng/mL for acanthoside D, 0.99–990.0 ng/mL for acanthoside B and 1.01–1010.0 ng/mL for hyperin. The intra-day and inter-day precision was less than 11.4% and the relative error (RE was all within ±15%. The validated method was successfully applied to assess the pharmacokinetics characteristics after the extracts of Acanthopanax sessiliflorus fruits were orally administered to the Sprague-Dawley rat.

HPLC, NMR and MALDI-TOF MS analysis of condensed tannins from Lithocarpus glaber leaves with potent free radical scavenging activity.

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Zhang, Liang Liang; Lin, Yi Ming

2008-12-04

Using acid-catalyzed degradation in the presence of cysteamine, the condensed tannins from Lithocarpus glaber leaves were characterized, following thiolysis, by means of reversed-phase HPLC, 13C-NMR and matrix-assisted laser desorption/ionization time of flight mass spectrometry (MALDI-TOF MS) analyses. The thiolysis reaction products showed the presence of the procyanidin (PC) and prodelphinidin (PD) structures. The 13C-NMR spectrum revealed that the condensed tannins were comprised of PD (72.4%) and PC (27.6%), and with a greater content of cis configuration rather than the trans configuration of C2-C3. The MALDI-TOF MS analysis proved the presence of PD units, and the maximum degree of polymerization (DP) was an undecamer. The antioxidant activity of condensed tannins from L. glaber leaves was evaluated by using a free radical scavenging activity assay.

[Assay of Tetramethylpyrazine in Szechwan Lovage Rhizome and Cnidium Rhizome by HPLC-DAD-MS].

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Hong, Yuan-lin; Jin, Yu-qing; Yao, Yi-xin; Lin, Mao-yi; Wei, Bo-ping; Jiang, Wei-dong; Lu, Guang-hua

2015-01-01

To quantity the amount of tetramethylpyrazine in Szechwan Lovage Rhizome (Chuanxiong, the rhizome of Ligusticum chuanxiong Hort., CX) and Cnidium Rhizome(Japanese Chuanxiong, the rhizome of Cnidium officinale Makino, JCX) for quality assessment. An HPLC-DAD-MS technique was employed to detect tetramethylpyrazine in 27 CX and 10 JCX samples. Tetramethylpyrazine was separated on a Waters Symmetry C,, column (250 mm x 4. 6 mm, 5 µm). The mobile phase was methanol-acetonitrile-water(27: 1: 72) at a flow rate of 1. 0 mL/min. The column temperature was 35 °C. DAD detection wavelength was 280 nm, while electrospray ionization detector was set at positive mode to collect MS spectrum. In the total of 37 herb samples, 11 samples were found to contain tetramethylpyrazine with the mean amount of 2. 19 µg/g(n = 11). 6 of 27 CX samples and 5 of 10 JCX sample were found the existence of tetramethylpyrazine with the amount of 0. 60 - 11. 75 µg and 0. 61 - 3. 05 µg/g,respectively. The correlation was not found between tetramethylpyrazine and the cultivation area, morphological character, processing or storage method for CX and JCX samples. It was possible that tetramethylpyrazine resulted from the microbes in soil. The developed method is accurate to quantify tetramethylpyrazine in CX and JCX herbs. Both the two herbs indeed contain tetramethylpyrazine, but it is not suitable to be a chemical marker to assess the quality of CX and JCX owing to low content.

Analytical capabilities of high performance liquid chromatography - Atmospheric pressure photoionization - Orbitrap mass spectrometry (HPLC-APPI-Orbitrap-MS) for the trace determination of novel and emerging flame retardants in fish.

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Zacs, D; Bartkevics, V

2015-10-22

A new analytical method was established and validated for the analysis of 27 brominated flame retardants (BFRs), including so called "emerging" and "novel" BFRs (EBFRs and NBFRs) in fish samples. High performance liquid chromatography (HPLC) coupled to Orbitrap mass spectrometry (Orbitrap-MS) employing atmospheric pressure photoionization (APPI) interface operated in negative mode was used for the identification/quantitation of contaminants. HPLC-Orbitrap-MS analysis provided a fast separation of selected analytes within 14 min, thus demonstrating a high throughput processing of samples. The developed methodology was tested by intralaboratory validation in terms of recovery, repeatability, linear calibration ranges, instrumental and method limits of quantitation (i-LOQ and m-LOQ), and where possible, trueness was verified by analysis of certified reference materials (CRMs). Recoveries of analytes were between 80 and 119%, while the repeatability in terms of relative standard deviations (RSDs) was in the range from 1.2 to 15.5%. The measured values for both analyzed CRMs agreed with the provided consensus values, revealing the recovery of reference concentrations in 72-119% range. The elaborated method met the sensitivity criterion according to Commission Recommendation 2014/118/EU on monitoring of BFRs in food products for majority of the compounds. The concentrations of polybrominated diphenyl ethers (PBDEs) in real samples determined by HPLC-APPI-Orbitrap-MS method and validated gas chromatography-high-resolution mass spectrometry (GC-HRMS) method were found to be in a good agreement. Copyright © 2015 Elsevier B.V. All rights reserved.

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

International Nuclear Information System (INIS)

Wahlen, Raimund; Wolff-Briche, Celine

2003-01-01

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

Automated on-line solid phase extraction coupled to HPLC-APCI-MS detection as a versatile tool for the analysis of phenols in water samples

International Nuclear Information System (INIS)

Wissiack, R.

2001-05-01

In this work a liquid chromatography-atmospheric pressure chemical ionization-mass spectrometry (HPLC-APCI-MS) technique was developed for the determination of phenols and anilines in waste water samples. All relevant parameters were optimized for liquid chromatographic (LC) separation and mass spectrometric (MS) detection. Mass spectrometric detection was used in either negative ionization (NI) or positive ionization (PI) mode, which was depending on the physicochemical properties of the analyte. For screening analysis, full scan mode (SCAN) was used, while selected ion monitoring (SIM) mode of acquisition was used for maximum sensitivity. The optimal interface parameters and solvent compositions were evaluated, which mainly determined the ionization of analytes thus strongly influencing the sensitivity. The quasi-molecular ions were the most abundant signals both for phenols ([M-H]- in NI) and for anilines ([M+H]+ in PI). In general, fragmentation was hardly observed for one-ring phenols. Only fragmentation due to neutral losses of NO, HCl, NH3, CO2, CHO or CO from the functional groups were obtained via collision induced dissociation (CID) in a single quadrupole mass spectrometer. A further source of structural information was the relative intensity of positive and negative ions for one analyte: Only in the case of para-methyl substituted phenols, detection was also possible in positive ionization mode with reasonable sensitivity. In contrast to the phenols, anilines offered somewhat higher structural information due to increased fragmentation through CID, when detected in the positive ionization mode. The main goal of this work was the development of a method for the determination of US EPA priority phenols in different environmental matrices. As highest sensitivity and selectivity was required for this task, a preconcentrating step was necessary, and consequently solid phase extraction (SPE) was coupled on-line to HPLC-APCI-MS. The optimized method allowed the

Studies into the phenolic patterns of different tissues of pineapple (Ananas comosus [L.] Merr.) infructescence by HPLC-DAD-ESI-MS (n) and GC-MS analysis.

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Steingass, Christof B; Glock, Mona P; Schweiggert, Ralf M; Carle, Reinhold

2015-08-01

In a comprehensive study, more than 60 phenolic compounds were detected in methanolic extracts from different tissues of pineapple infructescence by high-performance liquid chromatography with diode array detection and electrospray ionisation multiple-stage mass spectrometry (HPLC-DAD-ESI-MS (n) ) as well as by gas chromatography-mass spectrometry (GC-MS). The analytical workflow combining both methods revealed numerous compounds assigned for the first time as pineapple constituents by their mass fragmentations. Pineapple crown tissue was characterised by depsides of p-coumaric and ferulic acid. In contrast, major phenolic compounds in pineapple pulp extracts were assigned to diverse S-p-coumaryl, S-coniferyl and S-sinapyl derivatives of glutathione, N-L-γ-glutamyl-L-cysteine and L-cysteine, which were also identified in the peel. The latter was additionally characterised by elevated concentrations of p-coumaric, ferulic and caffeic acid depsides and glycerides, respectively. Two peel-specific cyanidin hexosides were found. Elevated concentrations of isomeric N,N'-diferuloylspermidines may be a useful tool for the detection of fraudulent peel usage for pineapple juice production. Mass fragmentation pathways of characteristic pineapple constituents are proposed, and their putative biological functions are discussed.

Systematic HPLC/ESI-High Resolution-qTOF-MS Methodology for Metabolomic Studies in Nonfluorescent Chlorophyll Catabolites Pathway

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José Julián Ríos

2015-01-01

Full Text Available Characterization of nonfluorescent chlorophyll catabolites (NCCs and dioxobilane-type nonfluorescent chlorophyll catabolite (DNCC in peel extracts of ripened lemon fruits (Citrus limon L. was performed by HPLC/ESI-high resolution-qTOF-MS method. Compounds were identified in samples on the basis of measured accurate mass, isotopic pattern, and characteristic fragmentation profile with an implemented software postprocessing routine. Three NCC structures already identified in other vegetal tissues were present in the lemon fruit peels (Cl-NCC1; Cl-NCC2; Cl-NCC4 while a new structure not defined so far was characterized (Cl-NCC3. This catabolite exhibits an exceptional arrangement of the peripheral substituents, allowing concluding that the preferences for the NCC modifications could be a species-related matter.

Analysis of carbohydrates in Fusarium verticillioides using size-exclusion HPLC – DRI and direct analysis in real time ionization – time-of-flight – mass spectrometry (DART-MS)

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Direct analysis in real time ionization – time-of-flight – mass spectrometry (DART-MS) and size-exclusion HPLC – DRI are used, respectively, to qualitatively and quantitatively determine the carbohydrates extracted from the corn rot fungus Fusarium verticillioides. In situ permethylation in the DART...

Combined use of liquid chromatography-hybrid quadrupole time-of-flight mass spectrometry (LC-QTOF-MS) and high performance liquid chromatography with photodiode array detector (HPLC-DAD) in systematic toxicological analysis.

Science.gov (United States)

Broecker, Sebastian; Pragst, Fritz; Bakdash, Abdulsallam; Herre, Sieglinde; Tsokos, Michael

2011-10-10

Time of flight mass spectrometry provides new possibilities of substance identification by determination of the molecular formula from accurate molecular mass and isotope pattern. However, the huge number of possible isomers requires additional evidence. As a suitable way for routine performance of systematic toxicological analysis, a method for combined use of liquid chromatography-hybrid quadrupole time-of-flight mass spectrometry (LC-QTOF-MS) and high performance liquid chromatography with diode array detector (HPLC-DAD) was developed and applied to blood samples from 77 death cases. The blood samples were prepared by extraction with CH(2)Cl(2) and by protein precipitation with acetonitrile (1:4 (v/v)). The evaporated extracts were reconstituted in 35% acetonitril/0.1% formic acid/H(2)O and aliquots were injected for analysis by LC-QTOF-MS (Agilent 6530) and HPLC-DAD (Agilent 1200). A valve switching system enabled simultaneous operation of both separated chromatographic lines under their respective optimal conditions using the same autosampler. The ESI-QTOF-MS instrument was run in data dependent acquisition mode with switching between MS and MS/MS (cycle time 1.1s) and measuring the full mass spectra and the collision induced dissociation (CID) fragment spectra of all essential [M+H](+) ions. Libraries of accurate mass CID spectra (~2500 substances) and of DAD-UV spectra (~3300 substances) of the authors were used for substance identification. The application of this procedure is demonstrated in detail at four examples with multiple drug intake or administration. In the 77 cases altogether 198 substances were identified (87 by DAD and 195 by QTOF-MS) with a frequency between 1 and 20. In practical application, the sample preparation proved to be suitable for both techniques and for a wide variety of substances with different polarity. The automatic performance of the measurements was efficient and robust. Mutual confirmation, decrease of false positive and

Separation and HPLC-MS identification of phenolic antioxidants from agricultural residues: Almond hulls and grape pomace

DEFF Research Database (Denmark)

Rubilar, M.; Pinelo, Manuel; Shene, C.

2007-01-01

Almond hulls and grape pomace are residues abundantly generated by agricultural industries, which could be processed to obtain bioactive products. To this purpose, crude ethanol extracts from both agricultural byproducts were attained and subsequently fractionated in order to obtain an organic....../water fraction (FOW). Extracts and fractions were analyzed for antioxidant power and their phenolic components tentatively identified by HPLC-MS. Chromatographic peaks of almond hull extracts showed the occurrence of hydroxybenzoic and cinnamic acid derivatives, with minor presence of flavan-3-ols (ECG, EGCG...... was assessed by DPPH and TBARS assays. Almond hulls showed inhibition percentages lower than 50% in both assays, while the inhibition percentage ranged from 80% to 90% in pomace extracts. Red grape pomace extract was the most efficient antioxidant, with an EC50 value of 0.91 g/L for TBARS and 0.20 g/L for DPPH...

Anthocyanins and antioxidant capacities of six Chilean berries by HPLC-HR-ESI-ToF-MS.

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Ramirez, Javier E; Zambrano, Ricardo; Sepúlveda, Beatriz; Kennelly, Edward J; Simirgiotis, Mario J

2015-06-01

The HPLC profiles of six fruits endemic of the VIII region of Chile were investigated using high resolution mass analysis (HR-ToF-ESI-MS). The anthocyanin fingerprints generated for the fruits were compared and the antioxidant capacities measured by the scavenging of the DPPH radical, the ferric reducing antioxidant power (FRAP), the superoxide anion scavenging activity assay (SA), and correlated with the inhibition of lipid peroxidation in human erythrocytes (LP) and total content of phenolics, flavonoids and anthocyanins measured by spectroscopic methods. Several anthocyanins were identified, including 3-O-glycosides derivatives of delphinidin, cyanidin, petunidin, peonidin and malvidin. Three phenolic acids (feruloyl-quinic acid, chlorogenic acid, and neochlorogenic acid) and five flavonols (hyperoside, isoquercitrin, quercetin, rutin, myricetin and isorhamnetin) were also identified. Calafate fruits showed the highest antioxidant activity. However, the highest LP activity was found for Chilean blueberries (>95%) followed by calafate fruits (91.27%) and luma (83.4%). Copyright © 2014 Elsevier Ltd. All rights reserved.

Characterization of chemical constituents in Rhodiola Crenulate by high-performance liquid chromatography coupled with Fourier-transform ion cyclotron resonance mass spectrometer (HPLC-FT-ICR MS).

Science.gov (United States)

Han, Fei; Li, Yanting; Mao, Xinjuan; Xu, Rui; Yin, Ran

2016-05-01

In this work, an approach using high-performance liquid chromatography coupled with diode-array detection and Fourier-transform ion cyclotron resonance mass spectrometer (HPLC-FT-ICR MS) for the identification and profiling of chemical constituents in Rhodiola crenulata was developed for the first time. The chromatographic separation was achieved on an Inertsil ODS-3 column (150 mm × 4.6 mm,3 µm) using a gradient elution program, and the detection was performed on a Bruker Solarix 7.0 T mass spectrometer equipped with electrospray ionization source in both positive and negative modes. Under the optimized conditions, a total of 48 chemical compounds, including 26 alcohols and their glycosides, 12 flavonoids and their glycosides, 5 flavanols and gallic acid derivatives, 4 organic acids and 1 cyanogenic glycoside were identified or tentatively characterized. The results indicated that the developed HPLC-FT-ICR MS method with ultra-high sensitivity and resolution is suitable for identifying and characterizing the chemical constituents in R. crenulata. And it provides a helpful chemical basis for further research on R. crenulata. Copyright © 2016 John Wiley & Sons, Ltd. Copyright © 2016 John Wiley & Sons, Ltd.

A specific and sensitive HPLC-MS/MS micromethod for milrinone plasma levels determination after inhalation in cardiac patients.

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Gavra, Paul; Nguyen, Anne Q-N; Theoret, Yves; Litalien, Catherine; Denault, André Y; Varin, France

2014-10-01

Milrinone administered through inhalation is an emerging method aimed at specifically reducing pulmonary hypertension without affecting systemic pressures. Its administration has been shown to be useful both in patients undergoing cardiac surgery and for persistent pulmonary hypertension of the newborn. These populations are prone to receive many concomitant medications and/or blood sampling may require a low volume quantification method. To address these issues in view of pharmacokinetic studies, this article aims to develop and validate a specific and sensitive analytical assay using high performance liquid chromatography (HPLC) and tandem mass spectrometry (MS/MS) detection for the quantification of milrinone plasma concentrations after inhalation in patients undergoing cardiac surgery. Plasma samples (50 μL) were extracted using ethyl acetate. Milrinone was separated on a C18 analytical column at 50°C. The mobile phase consisted of methanol and 10 mM ammonium acetate (45:55 vol/vol). The electrospray was operated in the negative ionization mode and monitored the following mass transitions: m/z 212.1 → 140.0 at 36 eV for milrinone and m/z 252.1 → 156.1 at 32 eV for olprinone. Calibration curves followed a quadratic regression in the concentration range of 0.3125-640 ng/mL. The lower limit of quantification is 0.3125 ng/mL and is based on a low plasma volume of 50 μL. Mean drug recovery and accuracy were ≥72.3% and 96.0%, respectively. Intraday and interday precision coefficient of variation (%) was ≤7.4% and ≤11.5%, respectively. The specificity allowed milrinone quantification in the multidrug administration conditions of cardiopulmonary bypass. This validated micromethod proved to be highly sensitive and specific while using a low volume of plasma. Its low volume and its lower limit of quantification indicate that this approach is suitable for further characterization of milrinone pharmacokinetics in both adults (inhalation) and neonates.

[Development of Tianma HPLC fingerprint and discriminant analysis].

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Xiao, Jia-Jia; Huang, Hong; Lei, You-Cheng; Lin, Ting-Wen; Ma, Yue; Zhang, Jing; Zhang, Xing-Guo; Zhang, Da-Quan; Lv, Guang-Hua

2017-07-01

Tianma(the tuber of Gastrodia eleta) is a widely used and pricy Chinese herb. Its counterfeits are often found in herbal markets, which are the plant materials with similar macroscopic characteristics of Tianma. Moreover, the prices of Winter Tianma(cultivated Tianma) and Spring Tianma(mostly wild Tianma) have significant difference. However, it is difficult to identify the true or false, good or bad quality of Tianma samples. Thus, a total of 48 Tianma samples with different characteristics(including Winter Tianma, Spring Tianma, slice, powder, etc.) and 9 plant species 10 samples of Tianma counterfeits were collected and analyzed by HPLC-DAD-MS techniques. After optimizing the procedure of sample preparation, chromatographic and mass-spectral conditions, the HPLC chromatograms of all those samples were collected and compared. The similarities and Fisher discriminant analysis were further conducted between the HPLC chromatograms of Tianma and counterfeit, Winter Tianma and Spring Tianma. The results showed the HPLC chromatograms of 48 Tianma samples were similar at the correlation coefficient more than 0.848(n=48). Their mean chromatogram was simulated and used as Tianma HPLC fingerprint. There were 11 common peaks on the HPLC chromatograms of Tianma, in which 6 main peaks were chosen as characteristic peaks and identified as gastrodin, p-hydroxybenzyl alcohol, parishin A, parishin B, parishin C, parishin E, respectively by comparison of the retention time, UV and MS data with those of standard chemical compounds. All the six chemical compounds are bioactive in Tianma. However, the HPLC chromatograms of the 10 counterfeit samples were significantly different from Tianma fingerprint. The correlation coefficients between HPLC fingerprints of Tianma with the HPLC chromatograms of counterfeits were less than 0.042 and the characteristic peaks were not observed on the HPLC chromatograms of these counterfeit samples. It indicated the true or false Tianma can be

SFC-MS/MS as an orthogonal technique for improved screening of polar analytes in anti-doping control.

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Parr, Maria Kristina; Wuest, Bernhard; Naegele, Edgar; Joseph, Jan F; Wenzel, Maxi; Schmidt, Alexander H; Stanic, Mijo; de la Torre, Xavier; Botrè, Francesco

2016-09-01

HPLC is considered the method of choice for the separation of various classes of drugs. However, some analytes are still challenging as HPLC shows limited resolution capabilities for highly polar analytes as they interact insufficiently on conventional reversed-phase (RP) columns. Especially in combination with mass spectrometric detection, limitations apply for alterations of stationary phases. Some highly polar sympathomimetic drugs and their metabolites showed almost no retention on different RP columns. Their retention remains poor even on phenylhexyl phases that show different selectivity due to π-π interactions. Supercritical fluid chromatography (SFC) as an orthogonal separation technique to HPLC may help to overcome these issues. Selected polar drugs and metabolites were analyzed utilizing SFC separation. All compounds showed sharp peaks and good retention even for the very polar analytes, such as sulfoconjugates. Retention times and elution orders in SFC are different to both RP and HILIC separations as a result of the orthogonality. Short cycle times could be realized. As temperature and pressure strongly influence the polarity of supercritical fluids, precise regulation of temperature and backpressure is required for the stability of the retention times. As CO2 is the main constituent of the mobile phase in SFC, solvent consumption and solvent waste are considerably reduced. Graphical Abstract SFC-MS/MS vs. LC-MS/MS.

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

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

2014-12-01

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

Antioxidant, Biomolecule Oxidation Protective Activities of Nardostachys jatamansi DC and Its Phytochemical Analysis by RP-HPLC and GC-MS

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Sakina Razack

2015-03-01

Full Text Available The study aimed at analyzing the metabolite profile of Nardostachys jatamansi using RP-HPLC, GC-MS and also its antioxidant, biomolecule protective and cytoprotective properties. The 70% ethanolic extract of Nardostachys jatamansi (NJE showed the presence of polyphenols and flavonoids (gallic acid, catechin, chlorogenic acid, homovanillin, epicatechin, rutin hydrate and quercetin-3-rhamnoside analyzed by RP-HPLC, whereas hexane extract revealed an array of metabolites (fatty acids, sesquiterpenes, alkane hydrocarbons and esters by GC-MS analysis. The antioxidant assays showed the enhanced potency of NJE with a half maximal inhibitory concentration (IC50 value of 222.22 ± 7.4 μg/mL for 2,2-diphenyl-1-picrylhydrazyl (DPPH, 13.90 ± 0.5 μg/mL for 2,2′-azino-bis(3-ethyl benzothiazoline-6-sulfonic acid diammonium salt (ABTS, 113.81 ± 4.2 μg/mL for superoxide, 948 ± 21.1 μg/mL for metal chelating and 12.3 ± 0.43 mg FeSO4 equivalent/g of extract for ferric reducing antioxidant power assays and was more potent than hexane extract. NJE effectively inhibited 2,2′-azobis(2-methylpropionamidine dihydrochloride (AAPH-induced oxidation of biomolecules analyzed by pBR322 plasmid DNA damage, protein oxidation of bovine serum albumin and lipid peroxidation assays. The observed effects might be due to the high content of polyphenols, 53.06 ± 2.2 mg gallic acid equivalents/g, and flavonoids, 25.303 ± 0.9 mg catechin equivalents/g, of NJE compared to the hexane fraction. Additionally, the extract abrogated the protein, carbonyl, and ROS formation, and NJE showed cytotoxicity in SH-SY5Y neuronal cells above 75 μg/mL. Thus, the study suggests that the herb unequivocally is a potential source of antioxidants and could aid in alleviating oxidative stress-mediated disorders.

Multi-Segment Direct Inject nano-ESI-LTQ-FT-ICR-MS/MS For Protein Identification

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Neal Rachel E

2011-07-01

Full Text Available Abstract Reversed phase high performance liquid chromatography (HPLC interfaced to electrospray tandem mass spectrometry (MS/MS is commonly used for the identification of peptides from proteolytically cleaved proteins embedded in a polyacrylamide gel matrix as well as for metabolomics screening. HPLC separations are time consuming (30-60 min average, costly (columns and mobile phase reagents, and carry the risk of column carry over between samples. The use of a chip-based nano-ESI platform (Advion NanoMate based on replaceable nano-tips for sample introduction eliminates sample cross-contamination, provides unchanging sample matrix, and enhances spray stability with attendant increases in reproducibility. Recent papers have established direct infusion nano-ESI-MS/MS utilizing the NanoMate for protein identification of gel spots based on full range MS scans with data dependent MS/MS. In a full range scan, discontinuous ion suppression due to sample matrix can impair identification of putative mass features of interest in both the proteomic and metabolomic workflows. In the current study, an extension of an established direct inject nano-ESI-MS/MS method is described that utilizes the mass filtering capability of an ion-trap for ion packet separation into four narrow mass ranges (50 amu overlap with segment specific dynamic data dependent peak inclusion for MS/MS fragmentation (total acquisition time of 3 minutes. Comparison of this method with a more traditional nanoLC-MS/MS based protocol utilizing solvent/sample stream splitting to achieve nanoflow demonstrated comparable results for protein identification from polyacrylamide gel matrices. The advantages of this method include full automation, lack of cross-contamination, low cost, and high throughput.

GC-MS determination of creatinine in human biological fluids as pentafluorobenzyl derivative in clinical studies and biomonitoring: Inter-laboratory comparison in urine with Jaffé, HPLC and enzymatic assays.

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Tsikas, Dimitrios; Wolf, Alexander; Mitschke, Anja; Gutzki, Frank-Mathias; Will, Wolfgang; Bader, Michael

2010-10-01

In consideration of its relatively constant urinary excretion rate, creatinine in urine is a useful biochemical parameter to correct the urinary excretion rate of endogenous and exogenous biomolecules. Assays based on the reaction of creatinine and picric acid first reported by Jaffé in 1886 still belong to the most frequently used laboratory approaches for creatinine measurement in urine. Further analytical methods for creatinine include HPLC-UV, GC-MS, and LC-MS and LC-MS/MS approaches. In the present article we report on the development, validation and biomedical application of a new GC-MS method for the reliable quantitative determination of creatinine in human urine, plasma and serum. This method is based on the derivatization of creatinine (d(0)-Crea) and the internal standard [methyl-trideutero]creatinine (d(3)-Crea) with pentafluorobenzyl (PFB) bromide in the biological sample directly or after dilution with phosphate buffered saline, extraction of the reaction products with toluene and quantification in 1-μl aliquots of the toluene extract by selected-ion monitoring of m/z 112 for d(0)-Crea-PFB and m/z 115 for d(3)-Crea-PFB in the electron-capture negative-ion chemical ionization mode. The limit of detection of the method is 100 amol of creatinine. In an inter-laboratory study on urine samples from 100 healthy subjects, the GC-MS method was used to test the reliability of currently used Jaffé, enzymatic and HPLC assays in clinical and occupational studies. The results of the inter-laboratory study indicate that all three tested methods allow for satisfactory quantification of creatinine in human urine. The GC-MS method is suitable for use as a reference method for urinary creatinine in humans. In serum, creatine was found to contribute to creatinine up to 20% when measured by the present GC-MS method. The application of the GC-MS method can be extended to other biological samples such as saliva. Copyright © 2010 Elsevier B.V. All rights reserved.

An HPLC-MS characterization of the changes in sweet orange leaf metabolite profile following infection by the bacterial pathogen Candidatus Liberibacter asiaticus.

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Hijaz, Faraj M; Manthey, John A; Folimonova, Svetlana Y; Davis, Craig L; Jones, Shelley E; Reyes-De-Corcuera, José I

2013-01-01

Huanglongbing (HLB) presumably caused by Candidatus Liberibacter asiaticus (CLas) threatens the commercial U.S. citrus crop of an annual value of $3 billion. The earliest shift in metabolite profiles of leaves from greenhouse-grown sweet orange trees infected with Clas, and of healthy leaves, was characterized by HPLC-MS concurrently with PCR testing for the presence of Clas bacteria and observation of disease symptoms. Twenty, 8-month-old 'Valencia' and 'Hamlin' trees were grafted with budwood from PCR-positive HLB source trees. Five graft-inoculated trees of each variety and three control trees were sampled biweekly and analyzed by HPLC-MS and PCR. Thirteen weeks after inoculation, Clas was detected in newly growing flushes in 33% and 55% of the inoculated 'Hamlin' and 'Valencia' trees, respectively. Inoculated trees remained asymptomatic in the first 20 weeks, but developed symptoms 30 weeks after grafting. No significant differences in the leaf metabolite profiles were detected in Clas-infected trees 23 weeks after inoculation. However, 27 weeks after inoculation, differences in metabolite profiles between control leaves and those of Clas-infected trees were evident. Affected compounds were identified with authentic standards or structurally classified by their UV and mass spectra. Included among these compounds are flavonoid glycosides, polymethoxylated flavones, and hydroxycinnamates. Four structurally related hydroxycinnamate compounds increased more than 10-fold in leaves from 'Hamlin' and 'Valencia' sweet orange trees in response to Clas infection. Possible roles of these hydroxycinnamates as plant defense compounds against the Clas infection are discussed.

Investigation of enrofloxacin residues in broiler tissues using ELISA and LC-MS/MS.

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Panzenhagen, Pedro Henrique N; Aguiar, Waldemir S; Gouvêa, Raquel; de Oliveira, Andréa M G; Barreto, Fabiano; Pereira, Virgínia L A; Aquino, Maria Helena C

2016-01-01

This study investigated the efficiency of an enrofloxacin ELISA test kit to detect the presence of enrofloxacin residues in broiler tissues compared with LC-MS/MS. Broiler tissues from 72 samples consisting of 60 breast muscle, six pools of livers (500 g each) and six pools of kidneys (500 g each) were obtained from six different slaughterhouses. Breast muscle from 10 carcasses and pools of livers and kidneys from approximately 200 carcasses of the same flock were collected from each slaughterhouse. ELISA and HPLC were used to identify and quantify the contamination of the samples with enrofloxacin. A total of 72% of the analysed samples contained enrofloxacin residues detected by the ELISA and 22.2% were detected by LC-MS/MS. The mean values of enrofloxacin contamination found in chicken breast by ELISA and HPLC were 8.63 and 12.25 μg kg(-1), respectively. None of the samples exceeded the maximum limit of 100 μg kg(-1) by both methods set by the European Union as well as the Brazilian Agriculture Ministry. All positive samples for enrofloxacin residues detected by LC-MS/MS were also positive by ELISA. These data confirm the efficiency of the ELISA test, and suggest its use as a screening method for enrofloxacin residues in poultry tissues due to its quick results, low price and ease of applicability.

Comparison of the effects of Mylabris and Acanthopanax senticosus on promising cancer marker polyamines in plasma of a Hepatoma-22 mouse model using HPLC-ESI-MS.

Science.gov (United States)

Wang, Qian; Wang, Yixiang; Liu, Ran; Yan, Xu; Li, Yujiao; Fu, Hui; Bi, Kaishun; Li, Qing

2013-02-01

A simple and sensitive method for the simultaneous determination of plasma concentrations of five polyamines in normal and Hepatoma-22 mice, and mice treated with Mylabris and Acanthopanax senticosus was developed by HPLC-ESI-MS. Male Kunming mice were divided into nine groups, a control group (inoculation without treatment), a positive group (Cyclophosphamide), treatment groups [Mylabris (4, 8, 16 mg/kg), Acanthopanax senticosus (6, 12, 24 g/kg)] and a normal group (without inoculation). Twenty-four hours after the last administration, plasma samples were collected. The derived polyamines were separated on a C(18) column by a gradient elution using methanol-water with excellent linearity within the range from 2.5 to 1000 ng/mL. Polyamines were confirmed as useful biochemical markers of hepatoma. The differences in anti-cancer therapeutic efficacy between Mylabris and Acanthopanax senticosus might contribute to the variability of polyamine levels in vivo. This HPLC-ESI-MS method was successfully applied to investigate the relationship between polyamines and cancer in mice and might be a useful method to test the activity of potential anti-tumor drugs. Copyright © 2012 John Wiley & Sons, Ltd.

[Determination of rhynchophylline and isorhynchophylline in Uncaria rhynchophylla by HPLC].

Science.gov (United States)

Yang, Xiu-Juan; Hong, Yan-Long; Wu, Fei; Ruan, Ke-Feng; Feng, Yi

2013-03-01

To explore an HPLC method for determination of rhnchophylline and isorhnchophylline in Uncaria rhnchophylla. An HPLC method has been developed for determination of rhnchophylline and isorhnchophylline. The transformation of rhnchophylline and isorhnchophylline after heating was also studied by HPLC-ESI-MS. Good linearities of rhynchophylline and isorhynchophylline were 0.064-5.100, 0.064-5.110 mg, respectively. The average recoveries were from 87.51% to 88.83% for rhynchophylline and from 107.9% to 113.9% for isorhynchophylline. The recoveries of rhynchophylline and isorhnchophylline reference solutions after extraction were 12.60% and 40.00% in the reflux extraction procedure, respectively. While in the ultrasonic extraction procedure, the average recoveries of rhynchophylline and isorhynchophylline was from 99.48% to 103.2% and from 97.00% to 99.59%, resepectively. The recoveries of rhynchophylline and isorhnchophylline reference solutions after extraction were 47.08% and 51.03%, respectively. The unqualified recovery could be elucidated by HPLC-ESI-MS analysis, indicating that trhynchophylline could be transformed mostly into isorhynchophylline and a little amount of unkown composition, while isorhynchophylline could be transformed into rhynchophylline isocorynoxeine, corynoxeine and 22-O-beta-D-glucopyranosyl isocorynoxeinic acid during the extraction procedure. Ultrasonic extraction procedure was more sutble for HPLC determination of the content of rhynchophylline and isorhynchophylline in U. rhnchophylla, however, the recovery problems should be paid attention to when it comes to the determination.

Identification of new derivatives of 2-S-glutathionylcaftaric acid in aged white wines by HPLC-DAD-ESI-MS(n).

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Cejudo-Bastante, María Jesús; Pérez-Coello, María Soledad; Hermosín-Gutiérrez, Isidro

2010-11-10

Glutathione, a natural occurring antioxidant, is a thiol-containing peptide present in grape must and wine. It is able to regenerate the o-diphenol group of enzymatically oxidized trans-caftaric acid, giving rise to 2-S-glutathionyl-trans-caftaric acid (also known as grape reaction product, GRP) and thus inhibiting the browning of wine. The amount of GRP present in a wine provides information on the oxidation history of the wine over its elaboration and aging. GRP has been proved to suffer hydrolysis in model solutions and wines. To know the actual content of glutathione involved in white wine browning inhibition as GRP, the GRP-derived products have been studied in 1-year-aged white wines by HPLC-DAD-ESI-MS(n). Online UV-vis spectra and pseudomolecular ions [(M + H)(+)] obtained by LC-MS supported the formation of some of the expected GRP hydrolysis products, mainly 2-S-glutathionyl-trans-caffeic acid (trans-GSCf), together with minor 2-S-(cysteinylglycyl)-trans-caftaric acid, 2-S-(γ-glutamylcysteinyl)-trans-caftaric acid, and 2-S-cysteinyl-trans-caftaric acid. On the basis of UV-vis and LC-MS(2) spectra, new GRP derivatives in aged white wines have been tentatively characterized for the first time as three monoethyl esters of GRP (GRP-Et) and also the cis isomers of GRP, GSCf, and some of the GRP-Et.

Simultaneous quantification of catechin, epicatechin, liquiritin, isoliquiritin, liquiritigenin, isoliquiritigenin, piperine and glycyrrhetinic acid in rat plasma by HPLC-MS/MS: application to a pharmacokinetic study of Longhu Rendan pills.

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Wang, Tianming; Ding, Liqing; Jin, Huajia; Shi, Rong; Li, Yuanyuan; Wu, Jiasheng; Li, Yifei; Zhu, Li; Ma, Yueming

2016-08-01

A sensitive, specific, accurate HPLC-MS/MS method was developed and validated for the simultaneous quantification of catechin, epicatechin, liquiritin, isoliquiritin, liquiritigenin, isoliquiritigenin, piperine and glycyrrhetinic acid from Longhu Rendan pills in rat plasma. Chromatographic separation was performed with a Hypersil Gold C18 column using a gradient of methanol and 0.01% acetic acid containing 0.2 mm ammonium acetate as mobile phase. The analytes were quantified on a triple quadrupole mass spectrometer, operating in selected reaction monitoring mode and switching the electrospray ion source polarity between positive and negative modes in a single run. The calibration curves of catechin, epicatechin, liquiritin, isoliquiritin, liquiritigenin, isoliquiritigenin, piperine and glycyrrhetinic acid were linear over the concentration ranges of 5-2000, 5-2000, 0.5-200, 0.5-200, 0.25-100, 0.25-100, 0.025-10 and 0.50-200 ng mL(-1) , respectively. The intra- and inter-assay precisions and accuracies were pills to rats. Copyright © 2016 John Wiley & Sons, Ltd. Copyright © 2016 John Wiley & Sons, Ltd.

Determination of free and esterified carotenoid composition in rose hip fruit by HPLC-DAD-APCI(+)-MS.

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Zhong, Lijie; Gustavsson, Karl-Erik; Oredsson, Stina; Głąb, Bartosz; Yilmaz, Jenny Lindberg; Olsson, Marie E

2016-11-01

Rose hip fruit, which contains high concentration of carotenoids is commonly used for different food products in Europe and it is considered to have medical properties. In this study, a simple, rapid and efficient HPLC-DAD-APCI(+)-MS method was developed and applied to identify and quantify the carotenoids in rose hip fruit of four rose species, including both unsaponified and saponified extract. In the unsaponified extract 23 carotenoid esters were detected, in which either rubixanthin ester or violaxanthin ester was the dominant component of the ester composition. In the saponified extract 21 carotenoids, including 11 xanthophylls and 10 carotenes were detected. This is the first time the total carotenoid composition, including the carotenoid esters in rose hip fruit were identified and quantified. This work reveals the potential of rose hip fruit to be utilized as a healthy dietary material and give chemical information for the possible future development in the pharmacology field. Copyright © 2016 Elsevier Ltd. All rights reserved.

Extensive characterisation of bioactive phenolic constituents from globe artichoke (Cynara scolymus L.) by HPLC-DAD-ESI-QTOF-MS.

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Abu-Reidah, Ibrahim M; Arráez-Román, David; Segura-Carretero, Antonio; Fernández-Gutiérrez, Alberto

2013-12-01

The aim of this work was to characterise the phenolic compounds in artichoke (hearts) by using HPLC coupled to DAD-ESI-QTOF-MS, which proved useful in characterising 61 phenolic and other polar compounds. Notably, of the 61 compounds characterised, 34 new phenolic compounds with their isomers have been tentatively characterised in artichoke for the first time, namely: 3 hydroxybenzoic acids, 17 hydroxycinnamic acids, 4 lignans, 7 flavones, 2 flavonols, and 1 phenol derivative. Moreover, a total of 28 isomers of previously described phenolics have also been detected. The data compiled from the qualitative polyphenol characterisation indicate that the artichoke extract analysed (Blanca de Tudela variety) could be regarded as a bioactive functional food and also as a promising source of antioxidant phenolic compounds. Copyright © 2013 Elsevier Ltd. All rights reserved.

Analysis of alcohol dehydrogenase inhibitors from Desmodium styracifolium using centrifugal ultrafiltration coupled with HPLC-MS

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Liu Liangliang

2015-01-01

Full Text Available Alcohol dehydrogenase (ADH inhibitors play an important role in the treatment of human methanol or ethylene glycol poisoning and the suppression of acetaldehyde accumulation in alcoholics. In this study, centrifugal ultrafiltration coupled with high performance liquid chromatography-mass spectrometry (HPLC-MS was utilized to screen and identify ADH inhibitors from ethyl acetate extract of Desmosium styracifolium (Osb. Merr. The experiment conditions of centrifugal ultrafiltration were optimized. At the optimum conditions (ADH concentration: 37.5 μg mL-1, incubation time: 90 min, pH: 7.0 and temperature: 15°C, formononetin and aromadendrin were successfully screened and identified from ethyl acetate extract of Desmodium styracifolium. The screening result was verified by ADH inhibition assays. The IC50 values of formononetin and aromadendrin were 70.8 and 84.7 μg mL-1, which were accorded with the binding degrees of them. Aromadendrin was first reported to have inhibitory activity on ADH. This method provided an effective way to screen active compounds from natural products.

Analysis of taxines in Taxus plant material and cell cultures by hplc photodiode array and hplc-electrospray mass spectrometry

NARCIS (Netherlands)

Theodoridis, G.; Laskaris, G.; Rozendaal, E.L.M.; Verpoorte, R.

2001-01-01

A semi-purified Taxus baccata needles extract was analysed by RP-HPLC. More than 18 taxines and cinnamates were detected by photodiode array detection and LC-MS, 10 of them being positively identified. Furthermore, 10-deacetyl baccatin III (paclitaxel's main precursor) and other taxanes were also

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

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

2018-02-01

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

[Pharmacokinetics of (-)-clausenamide and its major metabolite 6-hydroxyl-clausenamide in beagle dogs by HPLC/MS].

Science.gov (United States)

Song, Min; Qian, Wen; Hang, Tai-Jun; Zhang, Zheng-Xing

2005-10-01

To establish a sensitive and accurate method to study the pharmacokinetics of (-)-clausenamide [(-)-clau] and its major metabolite 6-hydroxyl-clausenamide (6-OH-clau) in the plasma of the Beagle dog. (-)-Clau was orally administered to six Beagle dogs at the dose of 30 mg x kg(-1), venous blood from front leg was sampled and plasma was separated for analysis. After extraction with ethyl acetate, the plasma samples were analyzed by HPLC/MS and the mobile phase was a mixture of methanol-water-acetic acid (60: 40: 0. 8) at the flow rate of 1.0 mL x min(-1). The API-ES positive ion SIM detection was carried out for the detection of both (-)-clau ([M + H] (+), m/z 298 ) and 6-OH-clau ([M + H - H2 O](+), m/z 296) with glipzide (glip) ([M + H](+), m/z 446) as internal standard. The pharmacokinetic parameters were calculated by 3P97 software. There was good linear relationship ( r > 0. 999) between the SIM responses and the concentrations for (-)-clau and 6-OH-clau at the range from 1.0 to 200 ng x mL(-1) and 0.2 to 40.0 ng x mL(-1), respectively. The absolute recovery was greater than 85%. The plasma concentration-time curves of (-)-clau and 6-OH-clau were both best fitted to a two-compartment model. The C(max) of (-)-clau and 6-OH-clau were (21 +/- 10) ng x mL(-1) and (3.9 +/- 2.2) ng x mL(-1), T(max) were (0.8 +/- 0.5) h and (1.3 +/- 0.5) h, T 1/2 alpha were (0.9 +/- 0.6) hand (1.4 +/- 0.6) h, T 1/2 beta were (19 +/- 23) hand (13 +/- 12) h, AUC(0-24 h) were (69 +/- 14) h x ng x mL(-1) and (12 +/- 7) h x ng x mL(-1) respectively. The established HPLC/MS method was sensitive and specific for the determination of (-)-clau. It was shown that the absorption and first phase elimination of (-)-clau were very quick in Beagle dogs, but the terminal elimination was very slow. The plasma concentration profile of its major metabolite 6-OH-clau was similar to (-)-clau and the AUC was relatively small in comparison with (-)-clau.

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

International Nuclear Information System (INIS)

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

2010-01-01

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

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

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

2010-01-11

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

Antioxidant Properties and Hyphenated HPLC-PDA-MS Profiling of Chilean Pica Mango Fruits (Mangifera indica L. Cv. piqueño

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Javier E. Ramirez

2013-12-01

Full Text Available Antioxidant capacities and polyphenolic contents of two mango cultivars from northern Chile, one of them endemic of an oasis in the Atacama Desert, were compared for the first time. Twenty one phenolic compounds were detected in peel and pulp of mango fruits varieties Pica and Tommy Atkins by HPLC-PDA-MS and tentatively characterized. Eighteen compounds were present in Pica pulp (ppu, 13 in Pica peel (ppe 11 in Tommy Atkins pulp (tpu and 12 in Tommy Atkins peel (tpe. Three procyanidin dimers (peaks 6, 9 and 10, seven acid derivatives (peaks 1–4, 11, 20 and 21 and four xanthones were identified, mainly mangiferin (peak 12 and mangiferin gallate, (peak 7, which were present in both peel and pulp of the two studied species from northern Chile. Homomangiferin (peak 13 was also present in both fruit pulps and dimethylmangiferin (peak 14 was present only in Tommy pulp. Pica fruits showed better antioxidant capacities and higher polyphenolic content (73.76/32.23 µg/mL in the DPPH assay and 32.49/72.01 mg GAE/100 g fresh material in the TPC assay, for edible pulp and peel, respectively than Tommy Atkins fruits (127.22/46.39 µg/mL in the DPPH assay and 25.03/72.01 mg GAE/100 g fresh material in the TPC assay for pulp and peel, respectively. The peel of Pica mangoes showed also the highest content of phenolics (66.02 mg/100 g FW measured by HPLC-PDA. The HPLC generated fingerprint can be used to authenticate Pica mango fruits and Pica mango food products.

Antioxidant properties and hyphenated HPLC-PDA-MS profiling of Chilean Pica mango fruits (Mangifera indica L. Cv. piqueño).

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Ramirez, Javier E; Zambrano, Ricardo; Sepúlveda, Beatriz; Simirgiotis, Mario J

2013-12-31

Antioxidant capacities and polyphenolic contents of two mango cultivars from northern Chile, one of them endemic of an oasis in the Atacama Desert, were compared for the first time. Twenty one phenolic compounds were detected in peel and pulp of mango fruits varieties Pica and Tommy Atkins by HPLC-PDA-MS and tentatively characterized. Eighteen compounds were present in Pica pulp (ppu), 13 in Pica peel (ppe) 11 in Tommy Atkins pulp (tpu) and 12 in Tommy Atkins peel (tpe). Three procyanidin dimers (peaks 6, 9 and 10), seven acid derivatives (peaks 1-4, 11, 20 and 21) and four xanthones were identified, mainly mangiferin (peak 12) and mangiferin gallate, (peak 7), which were present in both peel and pulp of the two studied species from northern Chile. Homomangiferin (peak 13) was also present in both fruit pulps and dimethylmangiferin (peak 14) was present only in Tommy pulp. Pica fruits showed better antioxidant capacities and higher polyphenolic content (73.76/32.23 µg/mL in the DPPH assay and 32.49/72.01 mg GAE/100 g fresh material in the TPC assay, for edible pulp and peel, respectively) than Tommy Atkins fruits (127.22/46.39 µg/mL in the DPPH assay and 25.03/72.01 mg GAE/100 g fresh material in the TPC assay for pulp and peel, respectively). The peel of Pica mangoes showed also the highest content of phenolics (66.02 mg/100 g FW) measured by HPLC-PDA. The HPLC generated fingerprint can be used to authenticate Pica mango fruits and Pica mango food products.

Hepatoprotective and antioxidant effect of Bauhinia hookeri extract against carbon tetrachloride-induced hepatotoxicity in mice and characterization of its bioactive compounds by HPLC-PDA-ESI-MS/MS.

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Al-Sayed, Eman; Martiskainen, Olli; Seif el-Din, Sayed H; Sabra, Abdel-Nasser A; Hammam, Olfat A; El-Lakkany, Naglaa M; Abdel-Daim, Mohamed M

2014-01-01

The hepatoprotective and antioxidant activity of Bauhinia hookeri ethanol extract (BHE) against CCl4-induced liver injury was investigated in mice. BHE was administered (500 and 1000 mg/kg/day) along with CCl4 for 6 weeks. The hepatic marker enzymes: alanine aminotransferase (ALT), aspartate aminotransferase (AST), and alkaline phosphatase (ALP) were determined in the serum. The antioxidant parameters: glutathione (GSH), superoxide dismutase (SOD), glutathione peroxidase (GPx), glutathione reductase (GR), glutathione transferase (GST), and malondialdehyde (MDA) were estimated in the liver homogenate. BHE treatment significantly inhibited the CCl4-induced increase in ALT (44 and 64%), AST (36 and 46%), ALP (28 and 42%), and MDA (39 and 51%) levels at the tested doses, respectively. Moreover, BHE treatment markedly increased the activity of antioxidant parameters GSH, GPx, GR, GST, and SOD. Histological observations confirmed the strong hepatoprotective activity. These results suggest that a dietary supplement of BHE could exert a beneficial effect against oxidative stress and various liver diseases by enhancing the antioxidant defense status, reducing lipid peroxidation, and protecting against the pathological changes of the liver. The hepatoprotective activity of BHE is mediated, at least in part, by the antioxidant effect of its constituents. The active constituents of BHE were identified by HPLC-PDA-ESI/MS/MS.

Simultaneous qualitative and quantitative analysis of phenolic acids and flavonoids for the quality control of Apocynum venetum L. leaves by HPLC-DAD-ESI-IT-TOF-MS and HPLC-DAD.

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An, Haijuan; Wang, Hong; Lan, Yuexiang; Hashi, Yuki; Chen, Shizhong

2013-11-01

A reliable method based on high performance liquid chromatography-diode array detector-electrospray ionization-ion trap-time of flight-mass spectrometry (HPLC-DAD-ESI-IT-TOF-MS) was developed for the identification of phenolic acids and flavonoids in Apocynum venetum L. leaves and its adulterant, Pocynum hendersonii (Hook. f.) Woodson leaves. A total of 21 compounds were identified or tentatively identified, including 4 phenolic acids and 17 flavonoids. 3-O-caffeoylquinic acid (3-CQA) and caffeic acid were detected for the first time in A. venetum leaves; 4-O-caffeoylquinic acid (4-CQA), 3-CQA, caffeic acid, quercetin-3-O-(6"-O-malonyl)-galactoside, quercetin-3-O-(6"-O-malonyl)-glucoside, kaempferol-3-O-(6"-O-malonyl)-glucoside, kaempferol-3-O-(6"-O-acetyl)-glucoside, and kaempferol-3-O-dihexoside were detected for the first time in P. hendersonii leaves. Cluster analysis was employed to analyze 24 batches of A. venetum leaves and 5 batches of P. hendersonii leaves collected from various regions in China. The analysis, which was based on the 21 compounds, indicated that profiles of these compounds were distinct between the two species, and among A. venetum leaf samples from different origins. 18 of these 21 compounds were selected as the markers and simultaneously analyzed by HPLC-DAD for the first time. The quantitative analytical method was validated and subsequently applied to the comprehensive quality evaluation of 24 batches of A. venetum leaves. © 2013 Elsevier B.V. All rights reserved.

Characterization of estrogen and androgen activity of food contact materials by different in vitro bioassays (YES, YAS, ERα and AR CALUX and chromatographic analysis (GC-MS, HPLC-MS.

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Johannes Mertl

Full Text Available Endocrine active substances (EAS show structural similarities to natural hormones and are suspected to affect the human endocrine system by inducing hormone dependent effects. Recent studies with in vitro tests suggest that EAS can leach from packaging into food and may therefore pose a risk to human health. Sample migrates from food contact materials were tested for estrogen and androgen agonists and antagonists with different commonly used in vitro tests. Additionally, chemical trace analysis by GC-MS and HPLC-MS was used to identify potential hormone active substances in sample migrates. A GC-MS method to screen migrates for 29 known or potential endocrine active substances was established and validated. Samples were migrated according to EC 10/2011, concentrated by solid phase extraction and tested with estrogen and androgen responsive reporter gene assays based on yeast cells (YES and YAS or human osteoblast cells (ERα and AR CALUX. A high level of agreement between the different bioassays could be observed by screening for estrogen agonists. Four out of 18 samples tested showed an estrogen activity in a similar range in both, YES and ERα CALUX. Two more samples tested positive in ERα CALUX due to the lower limits of detection in this assay. Androgen agonists could not be detected in any of the tested samples, neither with YAS nor with AR CALUX. When testing for antagonists, significant differences between yeast and human cell-based bioassays were noticed. Using YES and YAS many samples showed a strong antagonistic activity which was not observed using human cell-based CALUX assays. By GC-MS, some known or supposed EAS were identified in sample migrates that showed a biological activity in the in vitro tests. However, no firm conclusions about the sources of the observed hormone activity could be obtained from the chemical results.

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

Science.gov (United States)

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

2018-02-01

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

High performance liquid chromatography (HPLC fingerprints and primary structure identification of corn peptides by HPLC-diode array detection and HPLC-electrospray ionization tandem mass spectrometry

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Chi Wang

2016-01-01

Full Text Available Corn peptides (CPs are reported to have many biological functions, such as facilitating alcohol metabolism, antioxidation, antitumor, antihypertension, and hepatoprotection. To develop a method for quality control, the high-performance liquid chromatography (HPLC system was applied. Twenty-eight common peaks were found in all the CPs of corn samples from Enshi, China, based on which, a fingerprinting chromatogram was established for use in quality control in future research. Subsequently, the major chemical constituents of these common peaks were identified respectively using the HPLC-diode-array detection electrospray ionization tandem mass spectrometry (DAD-ESI-MS/MS system, and 48 peptide fractions were determined ultimately. This was the first time for the majority of these peptides to be reported, and many of them contained amino acids of glutamine (Q, L and A, which might play an important role in the exhibition of the bioactivities of CPs. Many peptides had a similar primary structure to the peptides which had been proven to be bioactive such as facilitating alcohol metabolism, scavenging free radicals, and inhibiting lipid peroxidation. This systematical analysis of the primary structure of CPs facilitated subsequent studies on the relationship between the structures and functions, and could accelerate holistic research on CPs.

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

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

2003-10-01

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

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

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

2007-03-01

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

Gamma radiolytic degradation of 4-chlorophenol determination of degraded products with HPLC and GC-MS

International Nuclear Information System (INIS)

Butt, S.B.; Masood, M.N.

2007-01-01

Contamination by chlorophenols of surface water and groundwater is an emerging issue in environmental science and engineering. After their usage as pesticide, herbicide and disinfectant, these organic compounds subsequently enter the aquatic environment through a number of routes. Some of the chlorophenols are slightly biodegradable, while others are more persistent and mobile in the aquatic environment especially chlorophenols. Gamma radiolytic degradation is one of advance oxidation process that has been thought to be one of the promising treatments to deal with this problem. This radiolytic study was carried out in methanolic 4-CP (4-chlorophenol) samples. Among several factors effecting radiolytic degradation of 4-CP, dose and concentration are important that were evaluated under atmospheric conditions. A degradation yield (G -value) for 4- CP of 0.38 and 1.35 was achieved in 20 and 100 mg/dm/sup 3/ solution. It was observed that degradation yield decreases with increasing 4-CP concentration. Gamma radiolysis produce free radicals in solvent which further react with 4-CP molecules to generate different products. The identification of degradation products was proposed using HPLC and GC-MS. (author)

Determination of Polar Compounds in Guava Leaves Infusions and Ultrasound Aqueous Extract by HPLC-ESI-MS

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Elixabet Díaz-de-Cerio

2015-01-01

Full Text Available Literature lacks publications about polar compounds content in infusion or guava leaves tea. Because of that, a comparison between different times of infusion and a conventional ultrasound aqueous extract was carried out. Several polar compounds have been identified by HPLC-ESI-MS and their antioxidant activity was evaluated by FRAP and ABTS assays. Four different classes of phenolic compounds (gallic and ellagic acid derivatives, flavonols, flavanones, and flavan-3-ols and some benzophenones were determined. The quantification results reported that the order, in terms of concentration of the classes of polar compounds in all samples, was flavonols > flavan-3-ols > gallic and ellagic acid derivatives > benzophenones > flavanones. As expected, the aqueous extract obtained by sonication showed the highest content in the compounds studied. Significative differences were noticed about the different times of infusion and five minutes was the optimal time to obtain the highest content in polar compounds using this culinary method. All the identified compounds, except HHDP isomers and naringenin, were positively correlated with antioxidant activity.

An Exploration on the Suitability of Airborne Carbonyl Compounds Analysis in relation to Differences in Instrumentation (GC-MS versus HPLC-UV and Standard Phases (Gas versus Liquid

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Ki-Hyun Kim

2014-01-01

Full Text Available The relative performance figure of merits was investigated for the two most common analytical methods employed for carbonyl compounds (CC, for example, between high performance liquid chromatography (HPLC-UV detector (with 2,4-dinitrophenylhydrazine (DNPH derivatization and thermal desorption (TD-gas chromatography (GC-mass spectrometry (MS (without derivatization. To this end, the suitability of each method is assessed by computing the relative recovery (RR between the gas- and liquid-phase standards containing a suite of CC such as formaldehyde (FA, acetaldehyde (AA, propionaldehyde (PA, butyraldehyde (BA, isovaleraldehyde (IA, and valeraldehyde (VA along with benzene (B as a recovery reference for the GC method. The results confirm that a TD-GC-MS is advantageous to attain the maximum recovery for the heavier CCs (i.e., with molecular weights (MW above BA−MW ≥ 74. On the other hand, the HPLC-UV is favorable for the lighter CCs (like FA and AA with the least bias. Such compound-specific responses for each platform are validated by relative ordering of CCs as a function of response factor (RF, method detection limit (MDL, and recovery pattern. It is thus desirable to understand the advantages and limitations of each method to attain the CC data with the least experimental bias.

Comparison of systemic absorption between ofloxacin ophthalmic in situ gels and ofloxacin conventional ophthalmic solutions administration to rabbit eyes by HPLC-MS/MS.

Science.gov (United States)

Li, Jiawei; Zhao, Hainan; Okeke, Chukwunweike Ikechukwu; Li, Lin; Liu, Zhidong; Yin, Zhongpeng; Zhuang, Pengwei; Sun, Jingtong; Wu, Tao; Wang, Meng; Li, Nan; Pi, Jiaxin; Zhang, Qian; Zhang, Rui; Ma, Li; Pang, Xiaochen; Liu, Zhanbiao; Zhang, Li; Fan, Lili

2013-06-25

In recent years, many pharmaceutical scientists have focused on developing the in situ gel-forming systems to overcome the poor bioavailability and therapeutic response exhibited by conventional ophthalmic solutions due to rapid pre-corneal elimination of the drug. The present work was to compare the systemic absorptions of ophthalmic ofloxacin in situ gel with the conventional ofloxacin eye drop after topical instillation to rabbit eyes by HPLC-MS/MS method and also determine the relative contribution of the nasal and the conjunctival mucosae to systemic ofloxacin absorption following topical instillation. The systemic AUC, Cmax, Tmax and Ke for ophthalmic in situ gel and ophthalmic solution after ocular instillation were 202.63±118.85 and 202.25±57.74 ng mL(-1) h, 54.22±28.31 and 48.4±25.97 ng mL(-1), 1.08±0.20 and 1.25±0.88 h, 0.0576±0.0207 and 0.0388±0.0248, respectively. And the values for the ratios of the AUC of anterior chamber of rabbit eye to blood plasma, AUCac/AUCpl, for ofloxacin conventional eye drop and in situ gel were 0.25 and 0.52, respectively. Statistic results showed that there was no significant difference in systemic absorption between the test groups and the reference groups (P>0.05) as both formulations have an AUCsa/AUCpl of 0.35. Therefore, the ophthalmic in situ gel may not decrease the drugs systemic absorption when administered in an equivalent dose as ophthalmic solutions into the rabbit eyes. Copyright © 2013 Elsevier B.V. All rights reserved.

Identification of Phenolic Compounds in Red and Green Pistachio (Pistacia vera L.) Hulls (Exo- and Mesocarp) by HPLC-DAD-ESI-(HR)-MS(n).

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Erşan, Sevcan; Güçlü Üstündağ, Özlem; Carle, Reinhold; Schweiggert, Ralf M

2016-07-06

Phenolic constituents of the nonlignified red and green pistachio hulls (exo- and mesocarp) were assessed by HPLC-DAD-ESI-MS(n) as well as by HR-MS. A total of 66 compounds was identified in the respective aqueous methanolic extracts. Among them, gallic acid, monogalloyl glucoside, monogalloyl quinic acid, penta-O-galloyl-β-d-glucose, hexagalloyl hexose, quercetin 3-O-galactoside, quercetin 3-O-glucoside, quercetin 3-O-glucuronide, and (17:1)-, (13:0)-, and (13:1)-anacardic acids were detected at highest signal intensity. The main difference between red and green hulls was the presence of anthocyanins in the former ones. Differently galloylated hydrolyzable tannins, anthocyanins, and minor anacardic acids were identified for the first time. Pistachio hulls were thus shown to be a source of structurally diverse and potentially bioactive phenolic compounds. They therefore represent a valuable byproduct of pistachio processing having potential for further utilization as raw material for the recovery of pharmaceutical, nutraceutical, and chemical products.

New findings on the in vivo antioxidant activity of Curcuma longa extract by an integrated (1)H NMR and HPLC-MS metabolomic approach.

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Dall'Acqua, Stefano; Stocchero, Matteo; Boschiero, Irene; Schiavon, Mariano; Golob, Samuel; Uddin, Jalal; Voinovich, Dario; Mammi, Stefano; Schievano, Elisabetta

2016-03-01

Curcuminoids possess powerful antioxidant activity as demonstrated in many chemical in vitro tests and in several in vivo trials. Nevertheless, the mechanism of this activity is not completely elucidated and studies on the in vivo antioxidant effects are still needed. Metabolomics may be used as an attractive approach for such studies and in this paper, we describe the effects of oral administration of a Curcuma longa L. extract (150 mg/kg of total curcuminoids) to 12 healthy rats with particular attention to urinary markers of oxidative stress. The experiment was carried out over 33 days and changes in the 24-h urine samples metabolome were evaluated by (1)H NMR and HPLC-MS. Both techniques produced similar representations for the collected samples confirming our previous study. Modifications of the urinary metabolome lead to the observation of different variables proving the complementarity of (1)H NMR and HPLC-MS for metabolomic purposes. The urinary levels of allantoin, m-tyrosine, 8-hydroxy-2'-deoxyguanosine, and nitrotyrosine were decreased in the treated group thus supporting an in vivo antioxidant effect of the oral administration of Curcuma extract to healthy rats. On the other hand, urinary TMAO levels were higher in the treated compared to the control group suggesting a role of curcumin supplementation on microbiota or on TMAO urinary excretion. Furthermore, the urinary levels of the sulphur containing compounds taurine and cystine were also changed suggesting a role for such constituents in the biochemical pathways involved in Curcuma extract bioactivity and indicating the need for further investigation on the complex role of antioxidant curcumin effects. Copyright © 2015 Elsevier B.V. All rights reserved.

Revealing metabolomic variations in Cortex Moutan from different root parts using HPLC-MS method.

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Xiao, Chaoni; Wu, Man; Chen, Yongyong; Zhang, Yajun; Zhao, Xinfeng; Zheng, Xiaohui

2015-01-01

The distribution of metabolites in the different root parts of Cortex Moutan (the root bark of Paeonia suffruticosa Andrews) is not well understood, therefore, scientific evidence is not available for quality assessment of Cortex Moutan. To reveal metabolomic variations in Cortex Moutan in order to gain deeper insights to enable quality control. Metabolomic variations in the different root parts of Cortex Moutan were characterised using high-performance liquid chromatography combined with mass spectrometry (HPLC-MS) and multivariate data analysis. The discriminating metabolites in different root parts were evaluated by the one-way analysis of variance and a fold change parameter. The metabolite profiles of Cortex Moutan were largely dominated by five primary and 41 secondary metabolites . Higher levels of malic acid, gallic acid and mudanoside-B were mainly observed in the second lateral roots, whereas dihydroxyacetophenone, benzoyloxypaeoniflorin, suffruticoside-A, kaempferol dihexoside, mudanpioside E and mudanpioside J accumulated in the first lateral and axial roots. The highest contents of paeonol, galloyloxypaeoniflorin and procyanidin B were detected in the axial roots. Accordingly, metabolite compositions of Cortex Moutan were found to vary among different root parts. The axial roots have higher quality than the lateral roots in Cortex Moutan due to the accumulation of bioactive secondary metabolites associated with plant physiology. These findings provided important scientific evidence for grading Cortex Moutan on the general market. Copyright © 2014 John Wiley & Sons, Ltd.

Isotope ratio monitoring LC/MS (IRM-LC/MS): new applications

International Nuclear Information System (INIS)

Juchelka, D; Hilkert, A.; Krummen, M.

2005-01-01

With the introduction of compound specific isotope analysis by isotope ratio monitoring GC/ MS (IRM-GC/MS) the immediate demand for similar applications using HPLC was created. Many compounds of biological, medical, pharmaceutical and environmental interest are not volatile or too polar. Consequently, they cannot be directly analyzed by gas chromatography. In IRM-GC/MS the carrier is helium, which does not interfere with the essential combust ion step prior to isotope ratio mass spectrometry (IRMS). In opposite the LC mobile phase has inhibited a similar direct conversion up to now. All earlier IRM-LC/MS approaches were based on the removal of the liquid phase prior to combustion risking fractionation of the isotope ratios of the eluted compounds. To avoid such restrictions we developed a new continuous flow concept for the coupling of an HPLC system to the isotope ratio MS for 13 C/ 12C isotope ratio analysis. In the Finnigan LC IsoLink, the liquid phase is not removed from the sample prior to oxidation. The sample is oxidized still in the mobile phase followed by on-line separation of the CO 2 from the liquid phase and transfer into the isotope ratio MS. Therefore, this strategy is based on water and inorganic buffers as mobile phase. The new approach opens up a whole new world in the application of gas isotope ratio mass spectrometry. The 13 C/ 12 C ratio s of organic acids, amino acids, carbohydrates and nucleotides can now be measured. These components typically within a complex matrix are separated by liquid chromatography followed by on-line determination of the isotope ratios. The draw backs of using derivatization and off-line preparation procedures can now be over come. This new technique allow s studying biochemical cycles, running tracer experiments and determining the origin of components. Applications from different scientific areas such as biogeochemistry, molecular biology, and pharmacy as well as authenticity control o f foods will be presented

Comparison of total phenolic content, scavenging activity and HPLC-ESI-MS/MS profiles of both young and mature leaves and stems of Andrographis paniculata.

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Chua, Lee Suan; Yap, Ken Choy; Jaganath, Indu Bala

2013-12-01

The total phenolic content and radical scavenging activity of Andrographis paniculata has been investigated to estimate the amount of phenolic compounds and diterpene lactones, respectively in the plant extracts. The stem extracts exhibited higher total phenolic content and scavenging activity than those of the leaf extracts from both young and mature plants. A range of 19.6-47.8 mg extract of A. paniculata from different parts of the plant is equivalent to the scavenging activity exhibited by one mg of standard Trolox. HPLC-ESI-MS/MS was also used to identify simultaneously the phytochemicals from the leaves and stems of both young and mature plant samples. Of the identified compounds, seven of the sixteen diterpene lactones, three of the six flavonoids, five of the six phenolic acids and two cyclic acids are reported here for the first time for this species. Multivariate statistical approaches such as Hierarchiral Component Analysis (HCA) and Principle Component Analysis (PCA) have clustered the plant extracts into the leaf and stem groups, regardless of plant age. Further classification based on the phytochemical profiles revealed that mostly phenolic acids and flavonoids were from the young leaf extracts, and diterpenoids and their glycosides from the mature leaf extracts. However, the phytochemical profiles for the stems of both young and mature plants were not significantly different as presented in the dendrogram of HCA and the score plot of PCA. The marker for mature plants might be the m/z 557 ion (dihydroxyl dimethyl 19-[(beta-D-glucopyranosyl)oxy]-19-oxo-ent-labda-8(17),13-dien-16,15-olide), whereas the m/z 521 ion (propyl neoandrographolide) could be the marker for leaf extracts.

Environmentally evaluated HPLC-ELSD method to monitor enzymatic synthesis of a non-ionic surfactant.

Science.gov (United States)

Gaber, Yasser; Akerman, Cecilia Orellana; Hatti-Kaul, Rajni

2014-01-01

N-Lauroyl-N-methylglucamide is a biodegradable surfactant derived from renewable resources. In an earlier study, we presented an enzymatic solvent-free method for synthesis of this compound. In the present report, the HPLC method developed to follow the reaction between lauric acid/methyl laurate and N-methyl glucamine (MEG) and its environmental assessment are described. Use of ultraviolet (UV) absorption or refractive index (RI) detectors did not allow the detection of N-methyl glucamine (MEG). With Evaporative light scattering detector ELSD, it was possible to apply a gradient elution, and detect MEG with a limit of detection, LOD = 0.12 μg. A good separation of the peaks: MEG, lauric acid, product (amide) and by-product (amide-ester) was achieved with the gradient program with a run time of 40 min. The setting of ELSD detector was optimized using methyl laurate as the analyte. LC-MS/MS was used to confirm the amide and amide-ester peaks. We evaluated the greenness of the developed method using the freely available software HPLC-Environmental Assessment Tool (HPLC-EAT) and the method got a scoring of 73 HPLC-EAT units, implying that the analytical procedure was more environmentally benign compared to some other methods reported in literature whose HPLC-EAT values scored up to 182. Use of ELSD detector allowed the detection and quantification of the substrates and the reaction products of enzymatic synthesis of the surfactant, N-lauroyl-N-methylglucamide. The developed HPLC method has acceptable environmental profile based on HPLC-EAT evaluation.

Development of an Advanced HPLC–MS/MS Method for the Determination of Carotenoids and Fat-Soluble Vitamins in Human Plasma

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Barbora Hrvolová

2016-10-01

Full Text Available The concentration of carotenoids and fat-soluble vitamins in human plasma may play a significant role in numerous chronic diseases such as age-related macular degeneration and some types of cancer. Although these compounds are of utmost interest for human health, methods for their simultaneous determination are scarce. A new high pressure liquid chromatography (HPLC-tandem mass spectrometry (MS/MS method for the quantification of selected carotenoids and fat-soluble vitamins in human plasma was developed, validated, and then applied in a pilot dietary intervention study with healthy volunteers. In 50 min, 16 analytes were separated with an excellent resolution and suitable MS signal intensity. The proposed HPLC–MS/MS method led to improvements in the limits of detection (LOD and quantification (LOQ for all analyzed compounds compared to the most often used HPLC–DAD methods, in some cases being more than 100-fold lower. LOD values were between 0.001 and 0.422 µg/mL and LOQ values ranged from 0.003 to 1.406 µg/mL, according to the analyte. The accuracy, precision, and stability met with the acceptance criteria of the AOAC (Association of Official Analytical Chemists International. According to these results, the described HPLC-MS/MS method is adequately sensitive, repeatable and suitable for the large-scale analysis of compounds in biological fluids.

Development of an Advanced HPLC–MS/MS Method for the Determination of Carotenoids and Fat-Soluble Vitamins in Human Plasma

Science.gov (United States)

Hrvolová, Barbora; Martínez-Huélamo, Miriam; Colmán-Martínez, Mariel; Hurtado-Barroso, Sara; Lamuela-Raventós, Rosa Maria; Kalina, Jiří

2016-01-01

The concentration of carotenoids and fat-soluble vitamins in human plasma may play a significant role in numerous chronic diseases such as age-related macular degeneration and some types of cancer. Although these compounds are of utmost interest for human health, methods for their simultaneous determination are scarce. A new high pressure liquid chromatography (HPLC)-tandem mass spectrometry (MS/MS) method for the quantification of selected carotenoids and fat-soluble vitamins in human plasma was developed, validated, and then applied in a pilot dietary intervention study with healthy volunteers. In 50 min, 16 analytes were separated with an excellent resolution and suitable MS signal intensity. The proposed HPLC–MS/MS method led to improvements in the limits of detection (LOD) and quantification (LOQ) for all analyzed compounds compared to the most often used HPLC–DAD methods, in some cases being more than 100-fold lower. LOD values were between 0.001 and 0.422 µg/mL and LOQ values ranged from 0.003 to 1.406 µg/mL, according to the analyte. The accuracy, precision, and stability met with the acceptance criteria of the AOAC (Association of Official Analytical Chemists) International. According to these results, the described HPLC-MS/MS method is adequately sensitive, repeatable and suitable for the large-scale analysis of compounds in biological fluids. PMID:27754400

A study of the red clover extract trinovin by ESR HPLC/MS and UVS

International Nuclear Information System (INIS)

Troup, G.; Hutton, D.; Hunter, C.; Hewitt, D.; Mulinacci, N.; Romani, A.; Pinelli, P.; Mancini, P.

1999-01-01

Full text: Trinovin is an extract of red clover, recently released on the dietary supplement market. It is recommended for 'Men's Health', because it contains the phenolics (isoflavones) genistein, biochanin, daidzein and formononetin, said to act as 'phytoestrogens', and is therefore a possible help in prostate gland problems. An Electron Spin Resonance (ESR) study (∼9.1Ghz, room temperature) revealed at least 3 different free radical lines, one with hyperfine structure, consistent with the listed molecules. Accordingly, HPLC/DAD (High Performance Liquid Chromatography/Diode Array Detector) and HPLC/Mass Spectroscopy analyses were performed in order to evaluate the quali-quantitative contents of flavonoidic compounds. The HPLC profile shows two main isoflavones and another three compounds, one of them being a quercetin glycoside. The quercetin glycosides are flavonoidic derivatives abundant in plant materials and present in wine. We can therefore say: even if the phytoestrogen properties claimed for Trinovin turn out to be less than hoped for, the antioxidants contained are very powerful, and so possibly helpful in protection against many diseases, including cancers, atherosclerosis, diabetic retinal bleeding, and non-alcoholic dementia

Application of HPLC and ESI-MS techniques in the analysis of phenolic acids and flavonoids from green leafy vegetables (GLVs

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B. Ramesh Kumar

2017-12-01

Full Text Available Diets containing high proportions of fruits and vegetables reduce the risk of onset of chronic diseases. The role of herbal medicines in improving human health is gaining popularity over the years, which also increases the need for safety and efficiency of these products. Green leafy vegetables (GLVs are the richest source of phenolic compounds with excellent antioxidant properties. Increased consumption of diets containing phenolic compounds may give positive and better results to human health and significantly improves the immune system. Highly selective, susceptible and versatile analytical techniques are necessary for extraction, identification, and quantification of phenolic compounds from plant extracts, which helps to utilize their important biological properties. Recent advances in the pre-treatment procedures, separation techniques and spectrometry methods are used for qualitative and quantitative analysis of phenolic compounds. The online coupling of liquid chromatography with mass spectrometry (LC–MS has become a useful tool in the metabolic profiling of plant samples. In this review, the separation and identification of phenolic acids and flavonoids from GLVs by LC–MS have been discussed along with the general extraction procedures and other sources of mass spectrometer used. The review is devoted to the understanding of the structural configuration, nature and accumulation pattern of phenolic acids and flavonoids in plants and to highlighting the recent developments in the chemical investigation of these compounds by chromatographic and spectroscopic techniques. It concludes with the advantages of the combination of these two methods and prospects. Keywords: Green leafy vegetables, Phenolic acids, Flavonoids, HPLC, ESI-MS

Analysis of pesticides in fruit, vegetables and cereals using methanolic extraction and detection by LC-MS/MS

DEFF Research Database (Denmark)

Granby, Kit; Andersen, Jens Hinge; Christensen, Hanne Bjerre

2004-01-01

Abstract: A method for analysing carbamates and other relatively polar pesticides by LC–MS–MS with electrospray ionisation has been developed. The method is based on extraction by ultrasonication using a methanolic ammonium acetate–acetic acid buffer. After centrifugation the samples are filtered...... in Miniprep filter HPLC vials and detected by LC–MS–MS. To compensate for variations in the MS response [13C6]-carbaryl was used as internal standard and matrix-matched pesticide solutions were used as external standards for the quantification. The method has been validated for the matrices apple, avocado...

Confirmation of Fructans biosynthesized in vitro from [1-13C]glucose in asparagus tissues using MALDI-TOF MS and ESI-MS.

Science.gov (United States)

Suzuki, Takashi; Maeda, Tomoo; Grant, Suzanne; Grant, Gordon; Sporns, Peter

2013-05-15

Accumulation of Fructans was confirmed in asparagus tissues that had been cultured for 2 days on media supplemented with glucose. It is very common that Fructans are biosynthesized from sucrose. We hypothesized however that Fructans could also be biosynthesized from glucose. Stem tissues of in vitro-cultured asparagus were subcultured for 72 h on a medium containing 0.5M of [1-(13)C]glucose. A medium containing 0.5M of normal ((12)C) glucose was used as control. Carbohydrates were extracted from the tissues and analyzed using HPLC, MALDI-TOF MS and ESI-MS. HPLC results indicated that the accumulation of short-chain Fructans was similar in both (13)C-labelled and control samples. Short-chain Fructans of DP=3-7 were detected using MALDI-TOF MS. The molecular mass of each oligomer in the (13)C-labelled sample was higher than the mass of the natural sample by 1 m/z unit per sugar moiety. The results of ESI-MS on the HPLC fractions of neokestose and 1-kestose showed that these oligomers (DP=3) were biosynthesized from exogenous glucose added to the medium. We conclude that not only exogenous sucrose but glucose can induce Fructan biosynthesis; fructans of both inulin type and inulin neoseries are also biosynthesized from glucose accumulated in asparagus tissues; the glucose molecules (or its metabolic products) were incorporated into Fructans as structural monomers. Copyright © 2013 Elsevier GmbH. All rights reserved.

Identification of C-geranylated flavonoids from Paulownia catalpifolia Gong Tong fruits by HPLC-DAD-ESI-MS/MS and their anti-aging effects on 2BS cells induced by H2O2.

Science.gov (United States)

Tang, Wen-Zhao; Wang, Ying-Ai; Gao, Tian-Yang; Wang, Xiao-Jing; Zhao, Yun-Xue

2017-05-01

The fruits of Paulownia catalpifolia Gong Tong are used as a Chinese folk herbal medicine for the treatment of enteritis, tonsillitis, bronchitis, and dysentery, etc. Our previous study has identified new C-geranylated flavanones with obvious anti-proliferative effects in lung cancer A549 cells. In the present study, a new C-geranylated flavone, paucatalinone C (1) and five known C-geranylated flavanones (2-6) were isolated. In addition, a total of 34 C-geranylated flavonoids were detected by HPLC-DAD-ESI-MS/MS coupling techniques from the CH 2 Cl 2 extract of P. catalpifolia. Futhermore, anti-aging effects of isolated compounds were evaluated in vitro with premature senescent 2BS cells induced by H 2 O 2 . Phytochemical results indicated that P. catalpifolia was a natural resource of abundant C-geranylated flavonoids. Diplacone (3) and paucatalinone A (5) were the potent anti-aging agents in the premature senescent 2BS cells induced by H 2 O 2 and the C-geranyl substituent may be an important factor because of its lipophilic character. Copyright © 2017 China Pharmaceutical University. Published by Elsevier B.V. All rights reserved.

Sample Preparation and Extraction in Small Sample Volumes Suitable for Pediatric Clinical Studies: Challenges, Advances, and Experiences of a Bioanalytical HPLC-MS/MS Method Validation Using Enalapril and Enalaprilat

Science.gov (United States)

Burckhardt, Bjoern B.; Laeer, Stephanie

2015-01-01

In USA and Europe, medicines agencies force the development of child-appropriate medications and intend to increase the availability of information on the pediatric use. This asks for bioanalytical methods which are able to deal with small sample volumes as the trial-related blood lost is very restricted in children. Broadly used HPLC-MS/MS, being able to cope with small volumes, is susceptible to matrix effects. The latter restrains the precise drug quantification through, for example, causing signal suppression. Sophisticated sample preparation and purification utilizing solid-phase extraction was applied to reduce and control matrix effects. A scale-up from vacuum manifold to positive pressure manifold was conducted to meet the demands of high-throughput within a clinical setting. Faced challenges, advances, and experiences in solid-phase extraction are exemplarily presented on the basis of the bioanalytical method development and validation of low-volume samples (50 μL serum). Enalapril, enalaprilat, and benazepril served as sample drugs. The applied sample preparation and extraction successfully reduced the absolute and relative matrix effect to comply with international guidelines. Recoveries ranged from 77 to 104% for enalapril and from 93 to 118% for enalaprilat. The bioanalytical method comprising sample extraction by solid-phase extraction was fully validated according to FDA and EMA bioanalytical guidelines and was used in a Phase I study in 24 volunteers. PMID:25873972

Sample Preparation and Extraction in Small Sample Volumes Suitable for Pediatric Clinical Studies: Challenges, Advances, and Experiences of a Bioanalytical HPLC-MS/MS Method Validation Using Enalapril and Enalaprilat

Directory of Open Access Journals (Sweden)

Bjoern B. Burckhardt

2015-01-01

Full Text Available In USA and Europe, medicines agencies force the development of child-appropriate medications and intend to increase the availability of information on the pediatric use. This asks for bioanalytical methods which are able to deal with small sample volumes as the trial-related blood lost is very restricted in children. Broadly used HPLC-MS/MS, being able to cope with small volumes, is susceptible to matrix effects. The latter restrains the precise drug quantification through, for example, causing signal suppression. Sophisticated sample preparation and purification utilizing solid-phase extraction was applied to reduce and control matrix effects. A scale-up from vacuum manifold to positive pressure manifold was conducted to meet the demands of high-throughput within a clinical setting. Faced challenges, advances, and experiences in solid-phase extraction are exemplarily presented on the basis of the bioanalytical method development and validation of low-volume samples (50 μL serum. Enalapril, enalaprilat, and benazepril served as sample drugs. The applied sample preparation and extraction successfully reduced the absolute and relative matrix effect to comply with international guidelines. Recoveries ranged from 77 to 104% for enalapril and from 93 to 118% for enalaprilat. The bioanalytical method comprising sample extraction by solid-phase extraction was fully validated according to FDA and EMA bioanalytical guidelines and was used in a Phase I study in 24 volunteers.

Applications of ICP-MS in marine analytical chemistry

Energy Technology Data Exchange (ETDEWEB)

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

1990-07-01

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

HPLC/MS identification of the polyphenols present in an extract of Myrtus communis L. obtained by supercritical fluid extraction

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Paula Pereira

2017-12-01

Full Text Available In this work, we studied an extract obtained by supercritical fluid extraction (SFE using a simpler method of cosolvent (ethanol addition. Instead of using a liquid pump, which is the most common process, the ethanol was directly introduced in the extraction cell, immediately after loading the cell with the plant sample. it was our intent to investigate if this change would have any effect in the composition of the extract obtained. The experimental conditions used were: temperature 48° C, pressure 10 MPa, supercritical fluid (SCF flow rate 130.71dm3h-1 (0.238 kgh-1 and an ethanol volume of 104 cm3. The composition of the extract obtained was different from previous tests, and the compounds identified by HPLC-MS were quinic acid, quinic acid 3,5-di-O-gallate, quinic acid 3,4,5-galloyl, myricetin-galactoside gallate, quercetin-galactoside gallate, quercetin, and myricetin-galactosiderhamnoside.

Characterization of Flavonoids and Phenolic Acids in Myrcia bella Cambess. Using FIA-ESI-IT-MSn and HPLC-PAD-ESI-IT-MS Combined with NMR

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Anne L. Dokkedal

2013-07-01

Full Text Available The leaves of Myrcia DC. ex Guill species are used in traditional medicine and are also exploited commercially as herbal drugs for the treatment of diabetes mellitus. The present work aimed to assess the qualitative and quantitative profiles of M. bella hydroalcoholic extract, due to these uses, since the existing legislation in Brazil determines that a standard method must be developed in order to be used for quality control of raw plant materials. The current study identified eleven known flavonoid-O-glycosides and six acylated flavonoid derivatives of myricetin and quercetin, together with two kaempferol glycosides and phenolic acids such as caffeic acid, ethil galate, gallic acid and quinic acid. In total, 24 constituents were characterized, by means of extensive preparative chromatographic analyses, along with MS and NMR techniques. An HPLC-PAD-ESI-IT-MS and FIA-ESI-IT-MSn method were developed for rapid identification of acylated flavonoids, flavonoid-O-glycosides derivatives of myricetin and quercetin and phenolic acids in the hydroalcoholic M. bella leaves extract. The FIA-ESI-IT-MS techinique is a powerful tool for direct and rapid identification of the constituents after isolation and NMR characterization. Thus, it could be used as an initial method for identification of authentic samples concerning quality control of Myrcia spp extracts.

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

International Nuclear Information System (INIS)

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

1998-01-01

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

Determination of Carbonyl Compounds in Cork Agglomerates by GDME-HPLC-UV: Identification of the Extracted Compounds by HPLC-MS/MS.

Science.gov (United States)

Brandão, Pedro Francisco; Ramos, Rui Miguel; Almeida, Paulo Joaquim; Rodrigues, José António

2017-02-08

A new approach is proposed for the extraction and determination of carbonyl compounds in solid samples, such as wood or cork materials. Cork products are used as building materials due to their singular characteristics; however, little is known about its aldehyde emission potential and content. Sample preparation was done by using a gas-diffusion microextraction (GDME) device for the direct extraction of volatile aldehydes and derivatization with 2,4-dinitrophenylhydrazine. Analytical determination of the extracts was done by HPLC-UV, with detection at 360 nm. The developed methodology proved to be a reliable tool for aldehyde determination in cork agglomerate samples with suitable method features. Mass spectrometry studies were performed for each sample, which enabled the identification, in the extracts, of the derivatization products of a total of 13 aldehydes (formaldehyde, acetaldehyde, furfural, propanal, 5-methylfurfural, butanal, benzaldehyde, pentanal, hexanal, trans-2-heptenal, heptanal, octanal, and trans-2-nonenal) and 4 ketones (3-hydroxy-2-butanone, acetone, cyclohexanone, and acetophenone). This new analytical methodology simultaneously proved to be consistent for the identification and determination of aldehydes in cork agglomerates and a very simple and straightforward procedure.

Analysis of Flavonoids in Lotus (Nelumbo nucifera Leaves and Their Antioxidant Activity Using Macroporous Resin Chromatography Coupled with LC-MS/MS and Antioxidant Biochemical Assays

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Ming-Zhi Zhu

2015-06-01

Full Text Available Lotus (Nelumbo nucifera leaves, a traditional Chinese medicinal herb, are rich in flavonoids. In an effort to thoroughly analyze their flavonoid components, macroporous resin chromatography coupled with HPLC-MS/MS was employed to simultaneously enrich and identify flavonoids from lotus leaves. Flavonoids extracted from lotus leaves were selectively enriched in the macroporous resin column, eluted subsequently as fraction II, and successively subjected to analysis with the HPLC-MS/MS and bioactivity assays. Altogether, fourteen flavonoids were identified, four of which were identified from lotus leaves for the first time, including quercetin 3-O-rhamnopyranosyl-(1→2-glucopyranoside, quercetin 3-O-arabinoside, diosmetin 7-O-hexose, and isorhamnetin 3-O-arabino- pyranosyl-(1→2-glucopyranoside. Further bioactivity assays revealed that these flavonoids from lotus leaves possess strong antioxidant activity, and demonstrate very good potential to be explored as food supplements or even pharmaceutical products to improve human health.

Simultaneous determination of sesquiterpenes and pyrrolizidine alkaloids from the rhizomes of Petasites hybridus (L.) G.M. et Sch. and dietary supplements using UPLC-UV and HPLC-TOF-MS methods.

Science.gov (United States)

Avula, Bharathi; Wang, Yan-Hong; Wang, Mei; Smillie, Troy J; Khan, Ikhlas A

2012-11-01

UPLC-UV and HPLC-TOF-MS methods have been developed for the analysis of major sesquiterpenes and pyrrolizidine alkaloids from rhizomes of Petasites hybridus (L.) G.M. et Sch. (Family, Asteracea) and dietary supplements claiming to contain P. hybridus. The best results were obtained with Acquity UPLC™ HSS T3 (100 mm × 2.1 mm, I.D., 1.8 μm) column system using a gradient elution with a mobile phase consisting of ammonium formate (50mM) and acetonitrile (0.05% formic acid) at a constant flow rate of 0.25 mL/min via UPLC-UV. The newly developed method was validated according to the ICH guidelines with respect to specificity, linearity, accuracy and precision. The limits of detection were found to be 5 μg/mL and 0.1 μg/mL for pyrrolizidine alkaloids and sesquiterpenes, respectively by UPLC-UV and 0.001 and 0.01 μg/mL, respectively using HPLC-TOF-MS. The methods were successfully used to analyze different P. hybridus market products, as well as to distinguish between two other Petasites species. The total content of petasins was found to be in the range of 0.02-11.6 mg/dosage form for 15 dietary supplements and no petasins were detected in an additional six dietary supplements. Additionally, pyrrolizidine alkaloids, which are considered to be toxic for the liver, were detected in seven dietary supplements. The amount of petasin in seven dietary supplements was found to be within limits of label claim and no pyrrolizidine alkaloids were detected. HPLC-mass spectrometry coupled with electrospray ionization (ESI) interface method is described for the identification and confirmation of sesquiterpenes and pyrrolizidine alkaloids from plant extracts and dietary supplements that claim to contain P. hybridus as well as different species of Petasites. Copyright © 2012 Elsevier B.V. All rights reserved.

Glycoproteins and protein glycations identified in barley grain and malt by 2D-HPLC

Czech Academy of Sciences Publication Activity Database

Žídková, Jitka; Petry-Podgorska, Inga; Laštovičková, Markéta; Bobálová, Janette

2013-01-01

Roč. 20, č. 1 (2013), s. 43 ISSN 1211-5894. [Discussion in Structural Molecular Biology /11./. 14.03.2013-16.03.2013, Nové Hrady] R&D Projects: GA ČR(CZ) GPP503/12/P395 Institutional support: RVO:68081715 Keywords : barley grain * glycoproteins * 2D-HPLC * MS/MS Subject RIV: CB - Analytical Chemistry, Separation

Identification of a Multicomponent Traditional Herbal Medicine by HPLC-MS and Electron and Light Microscopy.

Science.gov (United States)

Liu, Ju-Han; Cheng, Yung-Yi; Hsieh, Chen-Hsi; Tsai, Tung-Hu

2017-12-15

Commercial pharmaceutical herbal products have enabled people to take traditional Chinese medicine (TCM) in a convenient and accessible form. However, the quantity and quality should be additionally inspected. To address the issue, a combination of chemical and physical inspection methods were developed to evaluate the amount of an herbal formula, Xiang-Sha-Liu-Jun-Zi-Tang (XSLJZT), in clinical TCM practice. A high-performance liquid chromatography-tandem mass spectrometry (HPLC-MS) method with electrospray ionization was developed to measure the herbal biomarkers of guanosine, atractylenolide III, glycyrrhizic acid, dehydrocostus lactone, hesperidin, and oleanolic acid from XSLJZT. Scanning electron microscopy (SEM) photographs and light microscopy photographs with Congo red and iodine-KI staining were used to identify the cellulose fibers and starch content. Furthermore, solubility analysis, swelling power test, and crude fiber analysis were contributed to measure the starch additive in pharmaceutical products. The results demonstrated large variations in the chemical components of different pharmaceutical brands. The SEM photographs revealed that the starch was oval, smooth, and granular, and that the raw herbal powder appears stripy, stretched, and filiform. The stained light microscopy photographs of all of the pharmaceutical products showed added starch and raw herbal powder as extenders. The developed chemical and physical methods provide a standard operating procedure for the quantity control of the herbal pharmaceutical products of XSLJZT.

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

International Nuclear Information System (INIS)

Kim, Soo Jin; Pak, Yong Nam

2016-01-01

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

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

Energy Technology Data Exchange (ETDEWEB)

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

2016-11-15

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

Effect of processing on the alkaloids in Aconitum tubers by HPLC-TOF/MS

Directory of Open Access Journals (Sweden)

Min Liu

2017-06-01

Full Text Available According to the Chinese Pharmacopoeia 2015, only processed Aconitum tubers can be clinically applied, and the effect of processing is unclear. This research aimed to explore the effect of processing on cardiac efficacy of alkaloids in Aconitum tubers. First, the chemical ingredients in unprocessed and processed Aconitum tubers were identified and compared by using high performance liquid chromatography time-of-flight mass spectrometry (HPLC-TOF/MS and multivariate pattern recognition methods. Then the representative alkaloids in Aconitum tubers, aconitine, benzoylaconine, and aconine, which belong to diester-diterpenoid alkaloids, monoester-diterpenoid alkaloids, and amine-diterpenoid alkaloids, respectively, were selected for further validation of attenuated mechanism. Subsequent pharmacological experiments with aconitine, benzoylaconine, and aconine in SD rats were used for validate the effect of processing on cardiac functions. After processing the Aconitum tubers, it was found that the contents of diester-diterpenoid alkaloids were reduced, and those of monoester-diterpenoid alkaloids and amine-diterpenoid alkaloids were increased, suggesting that diester-diterpenoid alkaloids were transformed into monoester-diterpenoid alkaloids and amine-diterpenoid alkaloids. Through further decocting the aconitine in boiling water, it was confirmed that the three alkaloids could be progressively transformed. Pharmacological experiments with aconitine, benzoylaconine, and aconine in SD rats showed that aconitine at a dose of 0.01 mg/kg and aconine at a dose of 10 mg/kg enhanced the cardiac function, while benzoylaconine at a dose of 2 mg/kg weakened the cardiac function. The effect of processing is attributed to the transformation of the most toxic diester-diterpenoid alkaloids into less toxic monoester-diterpenoid alkaloids and amine-diterpenoid alkaloids.

Glycyrrhiza glabra HPLC fractions: identification of Aldehydo Isoophiopogonone and Liquirtigenin having activity against multidrug resistant bacteria.

Science.gov (United States)

Rahman, Hazir; Khan, Ilyas; Hussain, Anwar; Shahat, Abdelaaty Abdelaziz; Tawab, Abdul; Qasim, Muhammad; Adnan, Muhammad; Al-Said, Mansour S; Ullah, Riaz; Khan, Shahid Niaz

2018-05-02

Medicinal plants have been founded as traditional herbal medicine worldwide. Most of the plant's therapeutic properties are due to the presence of secondary metabolites such as alkaloids, glycosides, tannins and volatile oil. The present investigation analyzed the High-Pressure Liquid Chromatography (HPLC) fractions of Glycyrrhiza glabra (Aqueous, Chloroform, Ethanol and Hexane) against multidrug resistant human bacterial pathogens (Escherichia coli, Acinetobacter baumannii, Staphylococcus aureus and Pseudomonas aeruginosa). All the fractions showed antibacterial activity, were subjected to LC MS/MS analysis for identification of bioactive compounds. Among total HPLC fractions of G. glabra (n = 20), three HPLC fractions showed potential activity against multidrug resistant (MDR) bacterial isolates. Fraction 1 (F1) of aqueous extracts, showed activity against A. baumannii (15 ± 0.5 mm). F4 from hexane extract of G. glabra showed activity against S. aureus (10 ± 0.2 mm). However, F2 from ethanol extract exhibited activity against S. aureus (10 ± 0.3 mm). These active fractions were further processed by LC MS/MS analysis for the identification of compounds. Ellagic acid was identified in the F1 of aqueous extract while 6-aldehydo-isoophiopogonone was present in F4 of hexane extract. Similarly, Liquirtigenin was identified in F2 of ethanol. Glycyrrhiza glabra extracts HPLC fractions showed anti-MDR activity. Three bioactive compounds were identified in the study. 6-aldehydo-isoophiopogonone and Liquirtigenin were for the first time reported in G. glabra. Further characterization of the identified compounds will be helpful for possible therapeutic uses against infectious diseases caused by multidrug resistant bacteria.

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

Science.gov (United States)

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

2018-02-01

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

Matrix effects break the LC behavior rule for analytes in LC-MS/MS analysis of biological samples.

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Fang, Nianbai; Yu, Shanggong; Ronis, Martin Jj; Badger, Thomas M

2015-04-01

High-performance liquid chromatography (HPLC) and liquid chromatography-tandem mass spectrometry (LC-MS/MS) are generally accepted as the preferred techniques for detecting and quantitating analytes of interest in biological matrices on the basis of the rule that one chemical compound yields one LC-peak with reliable retention time (Rt.). However, in the current study, we have found that under the same LC-MS conditions, the Rt. and shape of LC-peaks of bile acids in urine samples from animals fed dissimilar diets differed significantly among each other. To verify this matrix effect, 17 authentic bile acid standards were dissolved in pure methanol or in methanol containing extracts of urine from pigs consuming either breast milk or infant formula and analyzed by LC-MS/MS. The matrix components in urine from piglets fed formula significantly reduced the LC-peak Rt. and areas of bile acids. This is the first characterization of this matrix effect on Rt. in the literature. Moreover, the matrix effect resulted in an unexpected LC behavior: one single compound yielded two LC-peaks, which broke the rule of one LC-peak for one compound. The three bile acid standards which exhibited this unconventional LC behavior were chenodeoxycholic acid, deoxycholic acid, and glycocholic acid. One possible explanation for this effect is that some matrix components may have loosely bonded to analytes, which changed the time analytes were retained on a chromatography column and interfered with the ionization of analytes in the MS ion source to alter the peak area. This study indicates that a comprehensive understanding of matrix effects is needed towards improving the use of HPLC and LC-MS/MS techniques for qualitative and quantitative analyses of analytes in pharmacokinetics, proteomics/metabolomics, drug development, and sports drug testing, especially when LC-MS/MS data are analyzed by automation software where identification of an analyte is based on its exact molecular weight and Rt

Direct quantification of lipopeptide biosurfactants in biological samples via HPLC and UPLC-MS requires sample modification with an organic solvent.

Science.gov (United States)

Biniarz, Piotr; Łukaszewicz, Marcin

2017-06-01

The rapid and accurate quantification of biosurfactants in biological samples is challenging. In contrast to the orcinol method for rhamnolipids, no simple biochemical method is available for the rapid quantification of lipopeptides. Various liquid chromatography (LC) methods are promising tools for relatively fast and exact quantification of lipopeptides. Here, we report strategies for the quantification of the lipopeptides pseudofactin and surfactin in bacterial cultures using different high- (HPLC) and ultra-performance liquid chromatography (UPLC) systems. We tested three strategies for sample pretreatment prior to LC analysis. In direct analysis (DA), bacterial cultures were injected directly and analyzed via LC. As a modification, we diluted the samples with methanol and detected an increase in lipopeptide recovery in the presence of methanol. Therefore, we suggest this simple modification as a tool for increasing the accuracy of LC methods. We also tested freeze-drying followed by solvent extraction (FDSE) as an alternative for the analysis of "heavy" samples. In FDSE, the bacterial cultures were freeze-dried, and the resulting powder was extracted with different solvents. Then, the organic extracts were analyzed via LC. Here, we determined the influence of the extracting solvent on lipopeptide recovery. HPLC methods allowed us to quantify pseudofactin and surfactin with run times of 15 and 20 min per sample, respectively, whereas UPLC quantification was as fast as 4 and 5.5 min per sample, respectively. Our methods provide highly accurate measurements and high recovery levels for lipopeptides. At the same time, UPLC-MS provides the possibility to identify lipopeptides and their structural isoforms.

Determination of taxonomic status of chinese species of the genus clematis by using high performance liquid chromatography-mass spectrometry (HPLC-MS) technique

International Nuclear Information System (INIS)

Ishtiaq, M.; Ahmed, H.

2010-01-01

A comparative taxonomic study using chemometric and numerical taxonomic approaches on 15 populations of 12 species of major taxa of the genus Clematis, belonging to sections, Rectae, Clematis, Meclatis, Tubulosae and Viorna were analyzed by HPLC coupled with diode array detector and ESI-MS. The chemo diversity profile of saponins proved to be useful taxonomic markers for the genus and results are presented in pheno grams. The compound 'Huzhangoside D' was the most abundant in analyzed species of the genus. Numerical taxonomic study was also conducted based on phylogenetically informative characters which corroborated with chemical fingerprinting findings. The significance of chemical markers in taxonomic study as well as their correlation between morphology and chemical compound profile is also debated with its significant role in botanic drugs identification. (author)

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

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

2000-02-01

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

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

Energy Technology Data Exchange (ETDEWEB)

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

2005-07-01

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

Effects of breviscapine on amyloid beta 1-42 induced Alzheimer's disease mice: A HPLC-QTOF-MS based plasma metabonomics study.

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Xia, Hongjun; Wu, Lingling; Chu, Mengying; Feng, Huimin; Lu, Chunliang; Wang, Qinghe; He, Minghai; Ge, Xiaoqun

2017-07-01

Herba Erigerontis has long been used to cure apoplexy hemiplegia and precordial pain in China. In addition, the bioactivities of its total flavonoids-breviscapine included inhibiting amyloid beta (Aβ) fibril formation, antioxidation and metal chelating, which are beneficial to treat Alzheimer's disease (AD). Hence, A HPLC-QTOF-MS based plasma metabonomics approach was applied to investigate the neuroprotective effects of breviscapine on intracerebroventricular injection of aggregated Aβ 1-42 induced AD mice for the first time in the study. Ten potential biomarkers were screened out by multivariate statistical analysis, eight of which were further identified as indoleacrylic acid, C16 sphinganine, LPE (22:6), sulfolithocholic acid, LPC (16:0), PA (22:1/0:0), taurodeoxycholic acid, and PC (0:0/18:0). According to their metabolic pathways, it was supposed that breviscapine ameliorated the learning and memory deficits of AD mice predominantly by regulating phospholipids metabolism, elevating serotonin level and lowering cholesterols content in vivo. Copyright © 2017 Elsevier B.V. All rights reserved.

Isolation and structural characterization of a novel sibutramine analogue, chlorosipentramine, in a slimming dietary supplement, by using HPLC-PDA, LC-Q-TOF/MS, FT-IR, and NMR.

Science.gov (United States)

Yun, Jisuk; Shin, Kye Jung; Choi, Jangduck; Jo, Cheon-Ho

2018-05-01

A novel sibutramine analogue was detected in a slimming formula by high performance liquid chromatography with a photo diode detector array (HPLC-PDA). The unknown compound exhibited an ultraviolet (UV) spectrum that was similar to that of chlorosibutramine, despite having a different HPLC retention time. Further analysis of the slimming formula by LC-quadrupole time-of-flight mass spectrometry (LC-Q-TOF/MS) showed that the unknown compound had the formula C 18 H 27 Cl 2 N. To elucidate the structure of this new sibutramine analogue, the target compound in the slimming formula was isolated on a preparative-LC system equipped with a PDA. After analysis by fourier transform infrared (FT-IR) and nuclear magnetic resonance (NMR) spectroscopy, the unknown compound was identified as a sibutramine analogue in which the iso-butyl group on the side chain is replaced with an iso-pentyl group. This new sibutramine analogue was identified to be 1-(1-(3,4-dichlorophenyl)cyclobutyl)-N,N,4-trimethylpentan-1-amine and has been named as chlorosipentramine. Copyright © 2018 Elsevier B.V. All rights reserved.

Stability-indicating HPLC-DAD/UV-ESI/MS impurity profiling of the anti-malarial drug lumefantrine.

Science.gov (United States)

Verbeken, Mathieu; Suleman, Sultan; Baert, Bram; Vangheluwe, Elien; Van Dorpe, Sylvia; Burvenich, Christian; Duchateau, Luc; Jansen, Frans H; De Spiegeleer, Bart

2011-02-28

Lumefantrine (benflumetol) is a fluorene derivative belonging to the aryl amino alcohol class of anti-malarial drugs and is commercially available in fixed combination products with β-artemether. Impurity characterization of such drugs, which are widely consumed in tropical countries for malaria control programmes, is of paramount importance. However, until now, no exhaustive impurity profile of lumefantrine has been established, encompassing process-related and degradation impurities in active pharmaceutical ingredients (APIs) and finished pharmaceutical products (FPPs). Using HPLC-DAD/UV-ESI/ion trap/MS, a comprehensive impurity profile was established based upon analysis of market samples as well as stress, accelerated and long-term stability results. In-silico toxicological predictions for these lumefantrine related impurities were made using Toxtree® and Derek®. Several new impurities are identified, of which the desbenzylketo derivative (DBK) is proposed as a new specified degradant. DBK and the remaining unspecified lumefantrine related impurities are predicted, using Toxtree® and Derek®, to have a toxicity risk comparable to the toxicity risk of the API lumefantrine itself. From unstressed, stressed and accelerated stability samples of lumefantrine API and FPPs, nine compounds were detected and characterized to be lumefantrine related impurities. One new lumefantrine related compound, DBK, was identified and characterized as a specified degradation impurity of lumefantrine in real market samples (FPPs). The in-silico toxicological investigation (Toxtree® and Derek®) indicated overall a toxicity risk for lumefantrine related impurities comparable to that of the API lumefantrine itself.

Monitoring of gamma radiolytic degradation products of methoxychlor pesticide in water by solid phase micro-extraction using hplc and GC-MS (abstract)

International Nuclear Information System (INIS)

Butt, S.B.; Zafar, A.

2011-01-01

Monitoring, removal and management of toxic chemicals is an essential area of study regarding sustainable progress. Different approaches are adopted to eliminate these water born toxics from water and waste water. Among these gamma radiolytic is an emerging option. This ionization radiation generates highly reactive radicals that reacts with pollutants and hence eliminates these. A solid-phase micro-extraction (SPME) procedure has been developed for the successful preconcentration of organic pollutant irradiated water. A SPME fused-silica fiber coated with Polyacrylate was used as a probe to extract the organic pollutant after irradiation. In this reference, degradation of priority organic pollutant methoxychlor (1, 1, 1-Trichloro 2, 2-bis (p-methoxyphenyl) ethane, in water by gamma irradiation under varied experimental conditions has been investigated. The degree of gamma radiolytic degradation was monitored by HPLC-UV and GC-MS. For 4 kGy and 5 kGy gamma radiation dose at a rate of 200 kGyh/sup -1/ greater or equal to 95 % and 98 % MXC was degraded respectively. The degradation products were identified by Mass Spectrometry after comparing their MS spectras with the NIST 98 library. The major degradation occurs via dechlorination, dehydro chlorination, by the detachment of methoxyphenyl from MXC and by interaction of other radicals generated by the water radiolysis. (author)

Analysis of primary aromatic amines using precolumn derivatization by HPLC fluorescence detection and online MS identification.

Science.gov (United States)

Zhao, Xianen; Suo, Yourui

2008-03-01

2-(2-phenyl-1H-phenanthro-[9,10-d]imidazole-1-yl)-acetic acid (PPIA) and 2-(9-acridone)-acetic acid (AAA), two novel precolumn fluorescent derivatization reagents, have been developed and compared for analysis of primary aromatic amines by high performance liquid chromatographic fluorescence detection coupled with online mass spectrometric identification. PPIA and AAA react rapidly and smoothly with the aromatic amines on the basis of a condensation reaction using 1-ethyl-3-(3-dimethylaminopropyl)-carbodiimide (EDC) as dehydrating catalyst to form stable derivatives with emission wavelengths at 380 and 440 nm, respectively. Taking six primary aromatic amines (aniline, 2-methylaniline, 2-methoxyaniline, 4-methylaniline, 4-chloroaniline, and 4-bromoaniline) as testing compounds, derivatization conditions such as coupling reagent, basic catalyst, reaction temperature and time, reaction solvent, and fluorescent labeling reagent concentration have also been investigated. With the better PPIA method, chromatographic separation of derivatized aromatic amines exhibited a good baseline resolution on an RP column. At the same time, by online mass spectrometric identification with atmospheric pressure chemical ionization (APCI) source in positive ion mode, the PPIA-labeled derivatives were characterized by easy-to-interpret mass spectra due to the prominent protonated molecular ion m/z [M + H](+) and specific fragment ions (MS/MS) m/z 335 and 295. The linear range is 24.41 fmol-200.0 pmol with correlation coefficients in the range of 0.9996-0.9999, and detection limits of PPIA-labeled aromatic amines are 0.12-0.21 nmol/L (S/N = 3). Method repeatability, precision, and recovery were evaluated and the results were excellent for the efficient HPLC analysis. The most important argument, however, was the high sensitivity and ease-of-handling of the PPIA method. Preliminary experiments with wastewater samples collected from the waterspout of a paper mill and its nearby soil where

An updated ciguatoxin extraction method and silica cleanup for use with HPLC-MS/MS for the analysis of P-CTX-1, PCTX-2 and P-CTX-3.

Science.gov (United States)

Meyer, Lauren; Carter, Steve; Capper, Angela

2015-12-15

Ciguatera fish poisoning is a debilitating human neuro-intoxication caused by consumption of tropical marine organisms, contaminated with bioaccumulated ciguatoxins (CTXs). The growing number of cases coupled with the high toxicity of CTXs makes their reliable detection and quantification of paramount importance. Three commonly occurring ciguatoxins, P-CTX-1, 2 and 3 from five different ciguatoxic Spanish mackerel (Scomberomorus commerson), were used to assess the effectiveness of different extraction techniques: homogenization (high powered blending vs. ultrasonication); C-18 column sizes (500 mg vs. 900 mg); and a novel HILIC SPE cleanup. Despite minor differences, blending and sonication proved equally effective. Larger 900 mg columns offered a greater extraction efficiency, increasing detected P-CTX-1 by 37% (P HPLC-MS/MS. Silica cleanup extraction efficiencies were also compared between the highly effective and validated ciguatoxin rapid extraction method (CREM) and current best practice extraction method employed by Queensland Health (QH). Overall, the QH protocol proved more effective, especially when paired with the newly adapted cleanup, as this increased the amount of extracted P-CTX-1 by 46% (P C-18 column and newly adapted HILIC SPE cleanup was most effective at extracting P-CTX-1, -2, -3. Specifically P-CTX-1, the primary ciguatoxin congener of concern due to its extremely high potency and an ability to cause CFP at 0.1 μg/kg following consumption of carnivorous fish flesh. Despite being more time intensive (an additional 85 min per batch of 12 samples), this will be especially effective for assessing lower toxin burdens, which may be near the limit of detection. Copyright © 2015 Elsevier Ltd. All rights reserved.

Quantification of active principles and pigments in leaf extracts of Isatis tinctoria by HPLC/UV/MS.

Science.gov (United States)

Mohn, Tobias; Potterat, Olivier; Hamburger, Matthias

2007-02-01

An HPLC method has been developed and validated for the quantification of the pharmacologically active principles tryptanthrin (1), 1,3-dihydro-3-[(4-hydroxy-3,5-dimethoxyphenyl)methylene]-2 H-indol-2-one (indolinone) (3), indirubin (4), alpha-linolenic acid (2), and indigo (5), an isomer of indirubin, in extracts from the traditional anti-inflammatory plant Isatis tinctoria (woad). The chromatographic separation was performed on a C-18 column with a linear gradient of acetonitrile in water containing 0.1% formic acid. The method combines UV and electrospray MS detection in the positive ion mode for the detection of the alkaloids, with a switch to the negative mode for the analysis of alpha-linolenic acid. The method was applied to the analysis of woad extracts obtained by supercritical fluid (SFE) CO2 extraction, and by pressurized liquid extraction (PLE) with dichloromethane and methanol, respectively. While the highest concentration of alpha-linolenic acid was found in the SFE extract (7.43%), the concentrations of tryptanthrin , indolinone, indirubin and indigo were the highest in the dichloromethane extract (0.30, 0.035, 2.48 and 0.84%, respectively). Compound 3 was not detected in the methanolic extract and only traces of compounds 1, 4 and 5 and low amount of alpha-linolenic acid (0.39%) were present in this extract.

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

International Nuclear Information System (INIS)

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

2012-01-01

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

Profiling and characterization of sialylated N-glycans by 2D-HPLC (HIAX/PGC) with online orbitrap MS/MS and offline MSn.

Science.gov (United States)

Hanneman, Andrew J S; Strand, James; Huang, Chi-Ting

2014-02-01

Glycosylation is a critical parameter used to evaluate protein quality and consistency. N-linked glycan profiling is fundamental to the support of biotherapeutic protein manufacturing from early stage process development through drug product commercialization. Sialylated glycans impact the serum half-life of receptor-Fc fusion proteins (RFPs), making their quality and consistency a concern during the production of fusion proteins. Here, we describe an analytical approach providing both quantitative profiling and in-depth mass spectrometry (MS)-based structural characterization of sialylated RFP N-glycans. Aiming to efficiently link routine comparability studies with detailed structural characterization, an integrated workflow was implemented employing fluorescence detection, online positive and negative ion tandem mass spectrometry (MS/MS), and offline static nanospray ionization-sequential mass spectrometry (NSI-MS(n)). For routine use, high-performance liquid chromatography profiling employs established fluorescence detection of 2-aminobenzoic acid derivatives (2AA) and hydrophilic interaction anion-exchange chromatography (HIAX) charge class separation. Further characterization of HIAX peak fractions is achieved by online (-) ion orbitrap MS/MS, offering the advantages of high mass accuracy and data-dependent MS/MS. As required, additional characterization uses porous graphitized carbon in the second chromatographic dimension to provide orthogonal (+) ion MS/MS spectra and buffer-free liquid chromatography peak eluants that are optimum for offline (+)/(-) NSI-MS(n) investigations to characterize low-abundance species and specific moieties including O-acetylation and sulfation. © 2013 Wiley Periodicals, Inc. and the American Pharmacists Association.

Cloud point extraction coupled with microwave-assisted back-extraction (CPE-MABE) for determination of Eszopiclone (Z-drug) using UV-Visible, HPLC and mass spectroscopic (MS) techniques: Spiked and in vivo analysis.

Science.gov (United States)

Kori, Shivpoojan; Parmar, Ankush; Goyal, Jony; Sharma, Shweta

2018-02-01

A procedure for the determination of Eszopiclone (ESZ) from complex matrices i.e. in vitro (spiked matrices), as well as in vivo (mice model) was developed using cloud point extraction coupled with microwave-assisted back-extraction (CPE-MABE). Analytical measurements have been carried using UV-Visible, HPLC and MS techniques. The proposed method has been validated according to ICH guidelines and legitimate reproducible and reliability of protocol is assessed through intraday and inter-day precision UV-Visible techniques, corresponding to assessed linearity range. The coaservate phase in CPE was back extracted under microwaves exposure, with isooctane at pre-concentration factor ~50 when 5mL of sample solution was pre-concentrated to 0.1mL. Under optimized conditions i.e. Aqueous-Triton X-114 4% (w/v), pH4.0, NaCl 4% (w/v) and equilibrium temperature of 45°C for 20min, average extraction recovery has been obtained between 89.8 and 99.2% and 84.0-99.2% from UV-Visible and HPLC analysis, respectively. The method has been successfully applied to the pharmacokinetic estimation (post intraperitoneal administration) of ESZ in mice. MS analysis precisely depicted the presence of active N‑desmethyl zopiclone in impales as well as in mice plasma. Copyright © 2018 Elsevier B.V. All rights reserved.

Using HPLC-Mass Spectrometry to Teach Proteomics Concepts with Problem-Based Techniques

Science.gov (United States)

Short, Michael; Short, Anne; Vankempen, Rachel; Seymour, Michael; Burnatowska-Hledin, Maria

2010-01-01

Practical instruction of proteomics concepts was provided using high-performance liquid chromatography coupled with a mass selective detection system (HPLC-MS) for the analysis of simulated protein digests. The samples were prepared from selected dipeptides in order to facilitate the mass spectral identification. As part of the prelaboratory…

HPLC-ESI-MS/MS assessment of the tetrahydro-metabolites of cortisol and cortisone in bovine urine: promising markers of dexamethasone and prednisolone treatment.

Science.gov (United States)

Chiesa, Luca; Panseri, Sara; Pavlovic, Radmila; Cannizzo, Francesca Tiziana; Biolatti, Bartolomeo; Divari, Sara; Villa, Roberto; Arioli, Francesco

2016-07-01

The effects of long-term administration of low doses of dexamethasone (DX) and prednisolone (PL) on the metabolism of endogenous corticosteroids were investigated in veal calves. In addition to cortisol (F) and cortisone (E), whose interconversion is regulated by 11β-hydroxysteroid dehydrogenases (11βHSDs), special attention was paid to tetrahydrocortisol (THF), allo-tetrahydrocortisol (aTHF), tetrahydrocortisone (THE) and allo-tetrahydrocortisone (aTHE), which are produced from F and E by catalytic activity of 5α and 5β-reductases. A specifically developed HPLC-ESI-MS/MS method achieved the complete chromatographic separation of two pairs of diastereoisomers (THF/aTHF and THE/aTHE), which, with appropriate mass fragmentation patterns, provided an unambiguous conformation. The method was linear (r(2) > 0.9905; 0.5-25 ng ml(-1)), with LOQQ of 0.5 ng ml(-1). Recoveries were in range 75-114%, while matrix effects were minimal. The experimental study was carried out on three groups of male Friesian veal calves: group PL (n = 6, PL acetate 15 mg day(-1) p.o. for 31 days); group DX (n = 5, 5 mg of estradiol (E2) i.m., weekly, and 0.4 mg day(-1) of DX p.o. for 31 days) and a control group (n = 8). Urine was collected before, during (twice) and at the end of treatment. During PL administration, the tetrahydro-metabolite levels decreased gradually and remained low after the suspension of treatment. DX reduced urinary THF that persisted after the treatment, while THE levels decreased during the experiment, but rebounded substantially after the DX was withdrawn. Both DX and PL significantly interfered with the production of F and E, leading to their complete depletion. Taken together, the results demonstrate the influence of DX and PL administration on 11βHSD activity and their impact on dysfunction of the 5-reductase pathway. In conclusion, profiling tetrahydro-metabolites of F and E might serve as an alternative, indirect but reliable, non

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

Science.gov (United States)

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

2018-06-15

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

Identification of some chemical constituents of Indigofera hirsuta Linn. (Fabaceae) by HPLC-ESI-MS (TOF) and evaluation of the anti radical activity

International Nuclear Information System (INIS)

Moura, Adriana Candido da Silva; Vilegas, Wagner; Santos, Lourdes Campaner dos

2011-01-01

A rapid analytical approach, suitable to characterize the compounds present in the aqueous and methanol extracts prepared from the aerial parts of Indigofera hirsute, was developed. The method based on high-performance liquid chromatography coupled to mass spectrometry, electrospray positive ionization and detection by time of flight (HPLC-ESI-MS-TOF) identified, tryptophan, uracil, rutin, kempferol-3-Oβ - -D-glucopyranoside, gallic acid and methyl gallate. The antiradical activity of this extract was evaluated using DPPH assay, with gallic acid as antiradical pattern. The study revealed the antiradical activity of methyl galatte (EC 50 = 5 ± 0.3 μg mL -1 ) gallic acid (EC 50 = 5 ± 0.2 μg mL -1 ) and rutin (EC 50 = 21.6 ± 0.6 μg m L -1 ), isolated from methanol extract (EC 50 = 67.7 ± 0.9 μg mL -1 ), which showed strong antiradical activity. (author)

Determination of Mycophenolic acid in the vitreous humor using the HPLC-ESI-MS/MS method: application of intraocular pharmacokinetics study in rabbit eyes with ophthalmic implantable device.

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Martins Duarte Byrro, Ricardo; de Oliveira Fulgêncio, Gustavo; Rocha Chellini, Paula; da Silva Cunha, Armando; Pianetti, Gerson Antônio

2013-10-01

Mycophenolic acid (MPA) is an immunosuppressive agent widely used in the treatment of solid organ transplant rejection. The success of MPA in the treatment of inflammatory intraocular diseases has been reported in recent literature. The treatment of inflammatory eye diseases in the posterior chamber is a challenge due to the anatomy of the eye, which presents certain barriers to drug access. Thus, the bioavailability of drugs in the eye is quite low, and successful drug delivery may well represent a key limiting factor to attaining a successful therapeutic strategy. Ophthalmic controlled drug delivery offers the potential to enhance the efficacy of treatment for pathological conditions. Thus, a novel delivery system based on a biodegradable polymeric device, which can be implanted inside the eye and deliver MPA directly to the target, is being developed. Specific analytical methods to determine the use of effective drugs within the eye are needed to characterize this device. A liquid chromatography-electrospray ionization tandem mass spectrometry (HPLC-ESI-MS/MS) method for the quantitation of MPA in the vitreous humor of rabbits was developed and validated. The vitreous was collected from rabbits, extracted by a protein precipitation extraction procedure and then separated on a C18 column with a mobile phase comprised of 0.15% aqueous acetic acid and methanol (60:40, v/v). The calibration curve was constructed within the range of 3-10,000 ng/mL for MPA. The mean R.S.D. values for the intra-run and inter-run precision were 5.15% and 4.35%. The mean accuracy value was 100.16%. The validated method was successfully applied to determine the MPA concentration in the vitreous humor of rabbits treated with an ocular implantable device. Copyright © 2013 Elsevier B.V. All rights reserved.

Analysis of Naturally Occurring Phenolic Compounds in Aromatic Plants by RP-HPLC Coupled to Diode Array Detector (DAD and GC-MS after Silylation

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Charalampos Proestos

2013-03-01

Full Text Available The following aromatic plants of Greek origin, Origanum dictamnus (dictamus, Eucalyptus globulus (eucalyptus, Origanum vulgare L. (oregano, Mellisa officinalis L. (balm mint and Sideritis cretica (mountain tea, were examined for the content of phenolic substances. Reversed phase HPLC coupled to diode array detector (DAD was used for the analysis of the plant extracts. The gas chromatography-mass spectrometry method (GC-MS was also used for identification of phenolic compounds after silylation. The most abundant phenolic acids were: gallic acid (1.5–2.6 mg/100 g dry sample, ferulic acid (0.34–6.9 mg/100 g dry sample and caffeic acid (1.0–13.8 mg/100 g dry sample. (+-Catechin and (−-epicatechin were the main flavonoids identified in oregano and mountain tea. Quercetin was detected only in eucalyptus and mountain tea.

Piper betle leaves: profiling phenolic compounds by HPLC/DAD-ESI/MS(n) and anti-cholinesterase activity.

Science.gov (United States)

Ferreres, Federico; Oliveira, Andreia P; Gil-Izquierdo, Angel; Valentão, Patrícia; Andrade, Paula B

2014-01-01

Piper betle L. is a widely distributed plant in the tropical and subtropical regions, its leaves being largely consumed as a masticator and mouth freshener. The purposes of this work were to characterise the phenolic profile of this species and to improve knowledge of its anti-cholinesterase properties. The phenolic composition of P. betle leaf aqueous and ethanol extracts was characterised by HPLC coupled with a diode-array detector and combined with electrospray ionisation tandem MS, and in vitro cholinesterase inhibitory capacity of both extracts was assessed by spectrophotometric microassays. The effect on neuronal cells (SH-SY5Y) viability was evaluated by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide reduction and lactate dehydrogenase leakage. Twelve phenolic compounds, comprising a phenylpropanoid, five cinnamoyl and six flavonoids derivatives were identified in P. betle leaves. Hydroxychavicol was the major compound in both extracts; however, the aqueous extract presented a greater diversity of compounds. Both extracts showed strong activity against both acetyl- and butyrylcholinesterase, which can be due, at least partially, to the phenolic composition. Furthermore, the aqueous extract proved to be cytotoxic to human neuroblastoma cells at concentrations higher than 500 µg/mL. The results suggest that the consumption of P. betle leaves as an infusion can have a positive impact in the prevention and treatment of neurodegenerative diseases. Apigenin and luteolin derivatives are reported for the first time in this species. Copyright © 2014 John Wiley & Sons, Ltd.

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

Science.gov (United States)

Nischwitz, V; Michalke, B; Kettrup, A

2003-01-01

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

Simultaneous determination of cucurbitacin B, E, I and E-glucoside in plant material and body fluids by HPLC-MS.

Science.gov (United States)

Bajcsik, Nicole; Pfab, Rudolf; Pietsch, Jörg

2017-05-01

A selective and sensitive analytical method for the simultaneous determination of cucurbitacin B, E, I and E-glucoside in plant material and body fluids by HPLC-MS was developed. After liquid-liquid extraction with dichlormethane, separation was achieved on a Phenomenex Luna Pentafluorophenyl Column (150mm×2mm, 5μm) using acetonitrile-water (90:10, v/v) as mobile phase system. Detection was performed using a 3200 Q Trap mass spectrometer (AB Sciex). For analysis Q1 Scans with negative ionisation were chosen. The method was validated for serum as the matrix of choice. Limits of detection are in the picogram range, limits of quantification are between 0.05 and 0.42ng/mL, recoveries are above 50%. The assay was linear in the calibration range from 1.0 to 50ng/mL for cucurbitacin E and from 0.10 to 50ng/mL for the cucurbitacins B, I and E-glucoside. The applicability of the method was demonstrated by the determination of cucurbitacins in zucchini plant material and body fluids from intoxication cases. Copyright © 2017 Elsevier B.V. All rights reserved.

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

Science.gov (United States)

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

2008-04-01

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

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

Science.gov (United States)

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

2014-05-20

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

2D-HPLC-MS phosphoproteomics analysis of lung and breast carcinomas

International Nuclear Information System (INIS)

Rocco, M.; Rubartelli, A.

2009-01-01

The project was conceived as two phases. In the first phase, we planned to validate markers, or expression patterns, previously described in the literature as being characteristic of specific tumors. In a second phase, a search for new markers associated with different tumors was to be carried on, developing new 2D-HPLC methods coupled with API-ESI mass spectrometry, with the ultimate goal of their rapid identification in biological specimens. For what concerns the first phase, the most relevant data are described in (Ceccarelli et al., 2008) and further analyzed in (Rubartelli et al., 2007). In these studies, we have compared the synthesis and intracellular accumulation levels of two oxido-reductases having also an extracellular cytokine function, the macrophage inhibitory factor (MIF) and thioredoxin (Trx)

Development and validation of a HPLC-MS/MS method for the determination of phytolaccagenin in rat plasma and application to a pharmacokinetic study.

Science.gov (United States)

Wei, Fenghuan; Singh, Ravi Shankar Prasad; Fueth, Matthias; Swarts, Steven; Okunieff, Paul; Derendorf, Hartmut

2015-03-25

Radix Phytolaccae (the dried root of Phytolacca acinosa Roxb. or Phytolacca americana L.) is widely used in East Asian countries for the treatment of inflammation-related diseases. The active component of Radix Phtolaccae is Phytolcaccagenin a triterpenoid saponin. Phytolcaccagenin has anti-inflammatory activities that exceed those of Esculentoside A and its derivatives regarding suppression of LPS-induced inflammation, and has a lower toxicity profile with less hemolysis. To date, no information is available about analytical method and pharmacokinetic studies of phytolaccagenin. To explore PK profile of this compound, a HPLC-MS/MS assay of phytolaccagenin in rat plasma was developed and validated. The method was fully validated according to FDA Guidance for industry. The detection was performed by a triple-quadrupole tandem mass spectrometer with multiple reactions monitoring (MRM) in positive ion mode via electrospray ionization. The monitored transitions were m/z 533.2>515.3 for Phytolcaccagenin, and 491.2>473.2 for I.S. The analysis was performed on a Symmetry C18 column (4.6 mm × 50 mm, 3.5 μm) using gradient elution with the mobile phase consisting of acetonitrile and 0.1% formic acid water at a flow rate of 1 ml/min with a 1:1 splitter ratio. The method was validated with a LLOQ of 20 ng/ml and an ULOQ of 1000 ng/ml. The response versus concentration data were fitted with 1/x weighting and the correlation coefficient (r) were greater than 0.999. The average matrix effect and the average extraction recovery were acceptable. This validation in rat plasma demonstrated that phytolaccagenin was stable for 30 days when stored below -20°C, for 6h at room temperature (RT, 22°C), for 12 h at RT for prepared control samples in auto-sampler vials, and during three successive freeze/thaw cycles results at -20°C. The validated method has been successfully applied to an intravenous bolus pharmacokinetic study of phytolaccagenin in male Sprague-Dawley rats (10 mg

HPLC-DAD-MS Profiling of Polyphenols Responsible for the Yellow-Orange Color in Apple Juices of Different French Cider Apple Varieties.

Science.gov (United States)

Le Deun, Erell; Van der Werf, Remmelt; Le Bail, Gildas; Le Quéré, Jean-Michel; Guyot, Sylvain

2015-09-09

The pigments responsible for the yellow-orange coloration of apple juices have remained largely unknown up to now. Four French cider apple juices were produced in conditions similar to those used in the cider-making industry. The oxidized juices, characterized using the CIE L a b parameters, displayed various colors depending on the apple variety and native phenolic composition. HPLC-DAD-MS revealed contrasting pigment profiles related to oxidized tanning and nontanning molecules. The latter were divided into two groups according to their polarity and their visible spectra. With regard to phenolic classes, flavanol monomers and hydroxycinnamic acids played an essential role in the formation of oxidation products. Interestingly, dihydrochalcones appeared to include precursors of some yellow compounds. Indeed, the yellow pigment phloretin xyloglucoside oxidation product (PXGOPj), derived from phloretin xyloglucoside, was clearly identified in apple juices as a xyloglucose analogue of the yellow pigment phloridzin oxidation product (POPj), previously characterized in a model solution by Le Guernevé et al. (Tetrahedron Lett. 2004, 45 (35), 6673-6677).

Improving N-Glycan Coverage using HPLC-MS with Electrospray Ionization at Subambient Pressure

Energy Technology Data Exchange (ETDEWEB)

Marginean, Ioan; Kronewitter, Scott R.; Moore, Ronald J.; Slysz, Gordon W.; Monroe, Matthew E.; Anderson, Gordon A.; Tang, Keqi; Smith, Richard D.

2012-10-01

Human serum glycan profiling with mass spectrometry (MS) has been employed to study several disease conditions and is demonstrating promise for e.g. clinical biomarker discovery. However, the poor glycan ionization efficiency and the large dynamic range of glycan concentrations in human sera hinder comprehensive profiling. In particular, large glycans are problematic because they are present at low concentrations and prone to fragmentation. Here we show that the sub-ambient pressure ionization with nanoelectrospray (SPIN)-MS can expand the serum glycome profile when compared with the conventional atmospheric pressure electrospray ionization (ESI)-MS with a heated capillary inlet. Notably, the ions generated by the SPIN interface were observed at higher charge states for 50% of the annotated glycans. Out of a total of 130 detected glycans, 34 were only detected with the SPIN-MS, resulting in improved coverage of glycan families as well as of glycans with larger numbers of labile monosaccharides.

Preparative separation and purification of bufadienolides from ChanSu by high-speed counter-current chromatography combined with preparative HPLC

International Nuclear Information System (INIS)

Li, Jialian; Zhang, Yongqing; Lin, Yunliang; Wang, Xiao; Fang, Lei; Geng, Yanling; Zhang, Qinde

2013-01-01

Eight bufadienolides were successfully isolated and purified from ChanSu by high-speed counter-current chromatography (HSCCC) combined with preparative HPLC (prep-HPLC). First, a stepwise elution mode of HSCCC with the solvent system composed of petroleum ether–ethyl acetate–methanol–water (4:6:4:6, 4:6:5:5, v/v) was employed and four bufadienolides, two partially purified fractions were obtained from 200 mg of crude extract. The partially purified fractions III and VI were then further separated by prepHPLC, respectively, and another four bufadienolides were recovered. Their structures were confirmed by ESI-MS and 1 H-NMR spectra. (author)

Improved liquid chromatography-MS/MS of heparan sulfate oligosaccharides via chip-based pulsed makeup flow.

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Huang, Yu; Shi, Xiaofeng; Yu, Xiang; Leymarie, Nancy; Staples, Gregory O; Yin, Hongfeng; Killeen, Kevin; Zaia, Joseph

2011-11-01

Microfluidic chip-based hydrophilic interaction chromatography (HILIC) is a useful separation system for liquid chromatography-mass spectrometry (LC-MS) in compositional profiling of heparan sulfate (HS) oligosaccharides; however, ions observed using HILIC LC-MS are low in charge. Tandem MS of HS oligosaccharide ions with low charge results in undesirable losses of SO(3) from precursor ions during collision induced dissociation. One solution is to add metal cations to stabilize sulfate groups. Another is to add a nonvolatile, polar compound such as sulfolane, a molecule known to supercharge proteins, to produce a similar effect for oligosaccharides. We demonstrate use of a novel pulsed makeup flow (MUF) HPLC-chip. The chip enables controlled application of additives during specified chromatographic time windows and thus minimizes the extent to which nonvolatile additives build up in the ion source. The pulsed MUF system was applied to LC-MS/MS of HS oligosaccharides. Metal cations and sulfolane were tested as additives. The most promising results were obtained for sulfolane, for which supercharging of the oligosaccharide ions increased their signal strengths relative to controls. Tandem MS of these supercharged precursor ions showed decreased abundances of product ions from sulfate losses yet more abundant product ions from backbone cleavages.

Analysis of flavonoids from propolis by on-line HPLC-electrospray mass spectrometry.

Science.gov (United States)

Volpi, Nicola; Bergonzini, Gianluca

2006-09-26

In this paper, the qualitative and quantitative separation and determination of the polyphenolic component of propolis preparations in the form of ethanolic extract, usually used for commercial pharmaceutical preparations, has been investigated by means of on-line HPLC-ESI/MS technique. Propolis of different origin have been evaluated for their components and a specific fingerprint has been determined potentially useful for the quality control of extracts in pharmaceutical preparations. The ethanolic extracts of propolis from Argentina, Italy and Spain shows approximately the same total ion chromatogram (TIC) profile due to the presence of the same molecular species, identified by the negative ESI-MS. On the contrary, the samples from Azerbaijan, China, Ethiopia and Kenya show a very peculiar TIC profiles. By using many purified flavonoids and calibration curves over a wide concentration range, from 0.05 (5 microg/ml) to 5 microg (500 microg/ml), an accurate assessment of the contents of several bioactive compounds in extract samples was performed. The propolis from Argentina, Italy and Spain show a great amount of pinocembrin (approximately 49%, 48% and 39% of the total identified flavonoids, respectively) and variable but similar percentages of the other species. On the contrary, the propolis from China, Azerbaijan and Ethiopia have a great amount of pinocembrin (approximately 63%, 46% and 62%, respectively) but no presence of genistein, kaempferol, apigenin and chrysin for the sample from China, genistein, kaempferol, acacetin and chrysin for the propolis from Azerbaijan, and no kaempferol and acacetin for the sample from Ethiopia. The ethanolic extract from propolis of Kenya has no identified flavonoid species but just a peak possessing a m/z of 253.0. Finally, an evaluation of the presence of total flavonoids for the various propolis samples was performed, with extracts from Argentina, Italy and Spain more rich in polyphenols than those from Azerbaijan, China

In Vitro Anticariogenic Effects of Drymocallis rupestris Extracts and Their Quality Evaluation by HPLC-DAD-MS3 Analysis

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Sebastian Granica

2013-07-01

Full Text Available In this study, for the first time, we investigated in vitro inhibitory effects of Drymocallis rupestris extracts and their subfractions obtained with solvents of different polarity (aqueous, 50% ethanolic, diethyl ether, ethyl acetate and n-butanolic against bacterial viability and caries virulence factors of Streptococcus spp. strains. The diethyl ether subfraction (PRU2 showed bacteriostatic and bactericidal activity against mutans streptococci, with minimum inhibitory concentrations (MICs in the range of 0.75–1.5 mg/mL and minimum bactericidal concentrations (MBCs in the range of 1.5–3 mg/mL. Furthermore, PRU2 inhibited biofilm formation by Streptococci in a dose-dependent manner. It was also found that all five D. rupestris preparations exhibited diverse inhibitory effects on de novo synthesis of water-insoluble and water-soluble α-d-glucans by glucosyltransferases of the mutans group streptococci. The phytochemical profile of investigated samples was determined by spectrophotometric and chromatographic (HPLC-DAD-MS3 methods. The high polyphenol (total phenol, phenolic acids, tannins, proantocyanidins, and flavonoids contents were found which correlated with anticariogenic activity of the analyzed samples. The results demonstrate that D. rupestris extracts and their subfractions could become useful supplements for pharmaceutical products as a new anticariogenic agent in a wide range of oral care products. Further studies are necessary to clarify which phytoconstituents of D. rupestris are responsible for anticaries properties.

Selective separation, detection of zotepine and mass spectral characterization of degradants by LC–MS/MS/QTOF

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M.V.N. Kumar Talluri

2014-04-01

Full Text Available A simple, precise, accurate stability-indicating gradient reversed-phase high-performance liquid chromatographic (RP–HPLC method was developed for the quantitative determination of zotepine (ZTP in bulk and pharmaceutical dosage forms in the presence of its degradation products (DPs. The method was developed using Phenomenex C18 column (250 mm×4.6 mm i.d., 5 µm with a mobile phase containing a gradient mixture of solvents, A (0.05% trifluoroacetic acid (TFA, pH=3.0 and B (acetonitrile. The eluted compounds were monitored at 254 nm; the run time was within 20.0 min, in which ZTP and its DPs were well separated, with a resolution of >1.5. The stress testing of ZTP was carried out under acidic, alkaline, neutral hydrolysis, oxidative, photolytic and thermal stress conditions. ZTP was found to degrade significantly in acidic, photolytic, thermal and oxidative stress conditions and remain stable in basic and neutral conditions. The developed method was validated with respect to specificity, linearity, limit of detection, limit of quantification, accuracy, precision and robustness as per ICH guidelines. This method was also suitable for the assay determination of ZTP in pharmaceutical dosage forms. The DPs were characterized by LC–MS/MS and their fragmentation pathways were proposed. Keywords: Zotepine, Stability-indicating RP–HPLC method, Characterization, ESI-Q-TOF-MS, Bulk drugs and formulations

Multiple Reaction Monitoring for quantitative laccase kinetics by LC-MS

DEFF Research Database (Denmark)

Perna, Valentina; Agger, Jane W.; Holck, Jesper

2018-01-01

as substrates to assess enzyme kinetics by HPLC-MS on two fungal laccases Trametes versicolor laccase, Tv and Ganoderma lucidum laccase, Gl. The method allowed accurate kinetic measurements and detailed insight into the product profiles of both laccases. Both Tv and Gl laccase are active...

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

Science.gov (United States)

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

2018-05-15

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

Crystal violet: Study of the photo-fading of an early synthetic dye in aqueous solution and on paper with HPLC-PDA, LC-MS and FORS

International Nuclear Information System (INIS)

Confortin, Daria; Brustolon, Marina; Franco, Lorenzo; Neevel, Han; Bommel, Maarten R van; Kettelarij, Albert J; Williams, Rene M

2010-01-01

The photo-fading of crystal violet (CV), one of the earliest synthetic dyes and an ink component, is examined both in solution and on paper. Aqueous solutions of CV were exposed to UV light (365nm) and samples were taken at constant time intervals and analysed with a High Performance Liquid Chromatography-Photo Diode Array (HPLC-PDA) and Liquid Chromatography-Mass Spectroscopy (LC-MS). Demethylation products were positively identified. Also, deamination probably occurred. The oxidation at the central carbon likely generates Michler's ketone (MK) or its derivatives, but still needs confirmation. To study CV on paper, Whatman paper was immersed in CV and exposed to UV light. Before and after different irradiation periods, reflectance spectra were recorded with Fibre Optic Reflectance Spectrophotometry (FORS). A decrease in CV concentration and a change in aggregation type for CV molecules upon irradiation was observed. Colorimetric L*a*b* values before and during irradiation were also measured. Also, CV was extracted from paper before and after different irradiation periods and analysed with HPLC-PDA. Photo-fading of CV on paper produced the same products as in solution, at least within the first 100 hours of irradiation. Finally, a photo-fading of CV in the presence of MK on Whatman paper was performed. It was demonstrated that MK both accelerates CV degradation and is consumed during the reaction. The degradation pathway identified in this work is suitable for explaining the photo/fading of other dyes belonging to the triarylmethane group.

HPLC based activity profiling for 5-lipoxygenase inhibitory activity in Isatis tinctoria leaf extracts.

Science.gov (United States)

Oberthür, C; Jäggi, R; Hamburger, M

2005-06-01

In the pursuit of the anti-inflammatory constituents in lipophilic woad extracts, the 5-lipoxygenase (5-LOX) inhibitory activity was investigated by HPLC-based activity profiling. In a low-resolution profiling, two time windows with peaks of activity were found. The first coincided with tryptanthrin, a known dual inhibitor of cyclooxygenase-2 (COX-2) and 5-LOX, whereas the major inhibitory fraction was towards the end of the HPLC run. The active fractions were profiled in a peak-resolved manner, and the compounds analyzed by LC-MS, GC and TLC. The activity in the lipophilic fractions of the Isatis extract could be linked to an unsaturated fatty acid, alpha-linolenic acid.

Preparative separation and purification of bufadienolides from ChanSu by high-speed counter-current chromatography combined with preparative HPLC

Energy Technology Data Exchange (ETDEWEB)

Li, Jialian; Zhang, Yongqing, E-mail: fleiv@163.com [College of Pharmacy, Shandong University of Traditional Chinese Medicine, Jinan, Shandong (China); Lin, Yunliang; Wang, Xiao; Fang, Lei; Geng, Yanling [Shandong Analysis and Test Center, Shandong Academy of Sciences, Jinan, Shandong (China); Zhang, Qinde [Shandong College of Traditional Chinese Medicine, Laiyang, Shandong (China)

2013-09-01

Eight bufadienolides were successfully isolated and purified from ChanSu by high-speed counter-current chromatography (HSCCC) combined with preparative HPLC (prep-HPLC). First, a stepwise elution mode of HSCCC with the solvent system composed of petroleum ether-ethyl acetate-methanol-water (4:6:4:6, 4:6:5:5, v/v) was employed and four bufadienolides, two partially purified fractions were obtained from 200 mg of crude extract. The partially purified fractions III and VI were then further separated by prepHPLC, respectively, and another four bufadienolides were recovered. Their structures were confirmed by ESI-MS and {sup 1}H-NMR spectra. (author)

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

Science.gov (United States)

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

2018-04-26

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

HPLC-MS Analysis of Lichen-Derived Metabolites in the Life Stages of Crambidia cephalica (Grote & Robinson).

Science.gov (United States)

Anderson, Timothy J; Wagner, David L; Cooper, Bruce R; McCarty, Megan E; Zaspel, Jennifer M

2017-01-01

Tiger moths (Lepidoptera: Erebidae: Arctiinae: Arctiini) are notable for their specialized associations with hosts that produce toxic secondary compounds, and are thus an ideal study system for understanding insect-plant interactions and the evolution of antipredatory defense. Likewise, their sister lineage (Arctiinae: Lithosiini) has been documented feeding on algae and lichens, and is known to sequester lichen-derived secondary compounds from the larval to adult stages. Prevalence of lichenivory in this early radiation (ca. 3000 species) may provide clues to the phylogenetic basis for storied chemical sequestration within all tiger moths. Despite the evolutionary significance of this trait, we lack a basic understanding of the extent of lichenivory among lithosiines, and the distribution of sequestered chemicals among life stages. The dynamics of chemical sequestration throughout the lifecycle for the lichen moth Crambidia cephalica were investigated by testing the hypothesis that lichen-derived metabolites are unequally distributed among life stages, and that laboratory-reared C. cephalica have less metabolite diversity than wild-caught individuals. Crambidia cephalica was reared on Physcia, and analyzed using high-performance liquid chromatography coupled to mass spectrometry (HPLC-MS). Several putative lichen-derived metabolites were detected across three life stages, i.e., larval, pupal, and adult, and differences among life stages and lichen host were observed. These results provide evidence that multiple lichen-derived metabolites are sequestered by C. cephalica; some metabolites are retained through adulthood, and others are lost or modified in earlier life stages. The presence of differing lichen-derived metabolites across life stages may indicate functional properties of the metabolites for C. cephalica with regards to chemical protection from antagonists, and other physiological processes.

Analysis of Wheat Prolamins, the Causative Agents of Celiac Sprue, Using Reversed Phase High Performance Liquid Chromatography (RP-HPLC and Matrix-Assisted Laser Desorption Ionization Time of Flight Mass Spectrometry (MALDI-TOF-MS

Directory of Open Access Journals (Sweden)

Jaime H. Mejías

2014-04-01

Full Text Available Wheat prolamins, commonly known as “gluten”, are a complex mixture of 71–78 proteins, which constitute ~80% of the proteins in the wheat grains and supply 50% of the global dietary protein demand. Prolamins are also responsible for numerous gluten-induced disorders and determine the unique visco-elastic properties of the wheat dough. These properties necessitate the reliable determination of the prolamin composition in wheat grains and their derived products. Therefore, this study examined the impact of HPLC conditions, including column type, column temperature, flow rate, and the gradient of polar and non-polar solvents in the mobile phase, to improve the analytical resolution of prolamins. The following conditions were found optimal for analyses: column temperature 60 °C, flow rate 1.0 mL/min and an elution gradient of 20%–60% of 0.1% trifluoroacetic acid + acetonitrile in 60 min. For further improvement of resolution, gliadin and glutenin extracts were analyzed using MALDI-TOF-MS in combination with HPLC fractionation. Two semi-quantitative methods, densitometry of stained polyacrylamide gels and HPLC, were used to determine relative prolamin quantities and the correspondence between the methods was established. The combinatorial gluten analyses approach developed during the present study was used to analyze prolamin profiles of wheat transformants expressing DEMETER silencing artificial microRNA, and the results are discussed.

LC-MS-MS Measurements of Urinary Creatinine and the Application of Creatinine Normalization Technique on Cotinine in Smokers’ 24 Hour Urine

OpenAIRE

Hongwei Hou; Wei Xiong; Xiaotao Zhang; Dongkui Song; Gangling Tang; Qingyuan Hu

2012-01-01

A simple and sensitive high performance liquid chromatography-tandem mass spectrometry (HPLC-ESI-MS-MS) method was developed and validated for the quantification of creatinine in human urine. The analysis was carried out on an Agilent Zorbax Eclipse XDB-C18 column (2.1 × 150 mm, 3.5  μ m). The mobile phase was 0.1% formic acid in water and 0.1% formic acid in acetonitrile (50/50, v/v). Linear calibration curves were obtained in the concentration range of 1–2000.0 ng/mL, with a lower limit of ...

Metabolic profiling study on potential toxicity and immunotoxicity-biomarker discovery in rats treated with cyclophosphamide using HPLC-ESI-IT-TOF-MS.

Science.gov (United States)

Li, Jing; Lin, Wensi; Lin, Weiwei; Xu, Peng; Zhang, Jianmei; Yang, Haisong; Ling, Xiaomei

2015-05-01

Despite the recent advances in understanding toxicity mechanism of cyclophosphamide (CTX), the development of biomarkers is still essential. CTX-induced immunotoxicity in rats by a metabonomics approach was investigated using high-performance liquid chromatography coupled with ion trap time-of-flight mass spectrometry (HPLC-ESI-IT-TOF-MS). The rats were orally administered CTX (30 mg/kg/day) for five consecutive days, and on the fifth day samples of urine, thymus and spleen were collected and analyzed. A significant difference in metabolic profiling was observed between the CTX-treated group and the control group by partial least squares-discriminant analysis (PLS-DA), which indicated that metabolic disturbances of immunotoxicity in CTX-treated rats had occurred. One potential biomarker in spleen, three in urine and three in thymus were identified. It is suggested that the CTX-toxicity mechanism may involve the modulation of tryptophan metabolism, phospholipid metabolism and energy metabolism. This research can help to elucidate the CTX-influenced pathways at a low dose and can further help to indicate the patients' pathological status at earlier stages of toxicological progression after drug administration. Copyright © 2014 John Wiley & Sons, Ltd.

Simultaneous screening of four epidermal growth factor receptor antagonists from Curcuma longa via cell membrane chromatography online coupled with HPLC-MS.

Science.gov (United States)

Sun, Meng; Ma, Wei-na; Guo, Ying; Hu, Zhi-gang; He, Lang-chong

2013-07-01

The epidermal growth factor receptors (EGFRs) are significant targets for screening active compounds. In this work, an analytical method was established for rapid screening, separation, and identification of EGFRs antagonists from Curcuma longa. Human embryonic kidney 293 cells with a steadily high expression of EGFRs were used to prepare the cell membrane stationary phase in a cell membrane chromatography model for screening active compounds. Separation and identification of the retention chromatographic peaks was achieved by HPLC-MS. The active sites, docking extents and inhibitory effects of the active compounds were also demonstrated. The screening result found that ar-turmerone, curcumin, demethoxycurcumin, and bisdemethoxycurcumin from Curcuma longa could be active components in a similar manner to gefitinib. Biological trials showed that all of four compounds can inhibit EGFRs protein secretion and cell growth in a dose-dependent manner, and downregulate the phosphorylation of EGFRs. This analytical method demonstrated fast and effective characteristics for screening, separation and identification of the active compounds from a complex system and should be useful for drug discovery with natural medicinal herbs. © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Determination of antibiotics such as macrolides, ionophores and tiamulin in liquid manure by HPLC-MS/MS.

Science.gov (United States)

Schlüsener, Michael P; Bester, Kai; Spiteller, Michael

2003-04-01

A method for the analysis of several macrolide and ionophore antibiotics as well as tiamulin in liquid manure was developed. Reversed-phase liquid chromatography and atmospheric pressure chemical ionisation (APCI) tandem mass spectrometry was used for detection.High-performance liquid chromatographic (HPLC) separation of the antibiotics was achieved in 35 min. The analytes were extracted with ethyl acetate and the extracts were cleaned up by solid-phase extraction on a diol SPE cartridge. Recovery experiments with spiked liquid manure concentrations varying from 6 to 2,000 microg kg(-1) gave constant recovery rates. The recovery rates for the macrolides erythromycin, roxithromycin and oleandomycin were 75-94%, that for the ionophore salinomycin was 119%, while that for the pleuromutilin tiamulin was 123%, when using a macrolide internal standard. The relative standard deviation was found to be 15-36% and the limits of detection were 0.4-11.0 micro g kg(-1). The maximum concentrations found in manure samples were 43 micro g kg(-1) for tiamulin and 11 micro g kg(-1) for salinomycin.

Analysis of zearalenone and α-zearalenol in 100 foods and medicinal plants determined by HPLC-FLD and positive confirmation by LC-MS-MS.

Science.gov (United States)

Kong, Wei-Jun; Shen, Hong-Hong; Zhang, Xiao-Fei; Yang, Xiao-Li; Qiu, Feng; Ou-yang, Zhen; Yang, Mei-Hua

2013-05-01

Mycotoxins, which may contaminate many foods and medicinal plants, are poisonous to humans. A high-performance liquid chromatography with fluorescence detection (HPLC-FLD) method was successfully developed for analysing the contamination levels of zearalenone (ZON) and its metabolite α-zearalenol (α-ZOL) in 100 widely consumed foods and medicinal plants in China. Samples were extracted with methanol-water (80:20, v/v), and cleaned up by using an immunoaffinity column. The limits of detection of this developed method for ZON and α-ZOL were 4 µg kg(-1) and 2.5 µg kg(-1) , respectively. Recoveries for the samples spiked with three levels (30, 60 and 300 µg kg(-1) for ZON and α-ZOL) ranged from 85.8% to 96.1% with relative standard deviation (RSD) of 2.6-7.1% for ZON, and from 89.9% to 98.7% with RSD of 1.9-9.2% for α-ZOL. Twelve (12%) of these tested samples were contaminated with ZON at levels ranging from 5.3 to 295.8 µg kg(-1). The most contaminated samples were Semen coicis, four of them in a concentration level exceeding 60 µg kg(-1) 'maximum level' (range 68.9-119.6 µg kg(-1)). Positive samples were further confirmed by liquid chromatography-tandem mass spectrometry. The results suggest that it is necessary to control ZON contamination in medicinal plants, especially Semen coicis. This is a successful study on the analysis of ZON and α-ZOL in medicinal plants in China by HPLC-FLD. Immunoaffinity clean-up and HPLC-FLD proved to have broad applicability in the field of simultaneously detecting ZON and α-ZOL in foods and medicinal plants and other complicated matrices. © 2012 Society of Chemical Industry.

Isolation by pressurised fluid extraction (PFE) and identification using CPC and HPLC/ESI/MS of phenolic compounds from Brazilian cherry seeds (Eugenia uniflora L.).

Science.gov (United States)

Oliveira, Alessandra L; Destandau, Emilie; Fougère, Laëtitia; Lafosse, Michel

2014-02-15

Brazilian cherry seeds are a waste product from juice and frozen pulp production and, the seeds composition was investigated to valorize this by-product. Compounds separation was performed with ethanol by pressurised fluid extraction (PFE). Here we determine the effect of temperature (T), static time (ST), number of cycles (C), and flush volume (VF) on the yield, composition and total phenolic content (TPC) of the seed extracts. T, ST and their interaction positively influenced yield and TPC. Extracts were fractionated by high performance liquid chromatography (HPLC) and centrifugal partition chromatography (CPC). The collected fractions characterizations were made by electrospray ionisation mass spectrometry (ESI/MS) and high resolution mass spectrometry (HRMS) indicated the presence of ellagic acid pentoside and deoxyhexose, quercitrin and kaempferol pentoside. All of these compounds have antioxidant properties and normally are found in plant extracts. These results confirm that Brazilian cherry seed extract is a potentially valuable source of antioxidants. Copyright © 2013 Elsevier Ltd. All rights reserved.

Pharmacokinetic Comparative Study of Gastrodin and Rhynchophylline after Oral Administration of Different Prescriptions of Yizhi Tablets in Rats by an HPLC-ESI/MS Method

Science.gov (United States)

Ge, Zhaohui; Liang, Qionglin; Wang, Yiming; Luo, Guoan

2014-01-01

Pharmacokinetic characters of rhynchophylline (RIN), gastrodin (GAS), and gastrodigenin (p-hydroxybenzyl alcohol, HBA) were investigated after oral administration of different prescriptions of Yizhi: Yizhi tablets or effective parts of tianma (total saponins from Gastrodiae, EPT) and gouteng (rhynchophylla alkaloids, EPG). At different predetermined time points after administration, the concentrations of GAS, HBA, and RIN in rat plasma were determined by an HPLC-ESI/MS method, and the main pharmacokinetic parameters were investigated. The results showed that the pharmacokinetic parameters C max and AUC0–∞ (P < 0.05) were dramatically different after oral administration of different prescriptions of Yizhi. The data indicated that the pharmacokinetic processes of GAS, HBA, and RIN in rats would interact with each other or be affected by other components in Yizhi. The rationality of the compatibility of Uncaria and Gastrodia elata as a classic “herb pair” has been verified from the pharmacokinetic viewpoint. PMID:25610474

Pharmacokinetic Comparative Study of Gastrodin and Rhynchophylline after Oral Administration of Different Prescriptions of Yizhi Tablets in Rats by an HPLC-ESI/MS Method

Directory of Open Access Journals (Sweden)

Zhaohui Ge

2014-01-01

Full Text Available Pharmacokinetic characters of rhynchophylline (RIN, gastrodin (GAS, and gastrodigenin (p-hydroxybenzyl alcohol, HBA were investigated after oral administration of different prescriptions of Yizhi: Yizhi tablets or effective parts of tianma (total saponins from Gastrodiae, EPT and gouteng (rhynchophylla alkaloids, EPG. At different predetermined time points after administration, the concentrations of GAS, HBA, and RIN in rat plasma were determined by an HPLC-ESI/MS method, and the main pharmacokinetic parameters were investigated. The results showed that the pharmacokinetic parameters Cmax and Cmax⁡ and AUC0–∞ (P<0.05 were dramatically different after oral administration of different prescriptions of Yizhi. The data indicated that the pharmacokinetic processes of GAS, HBA, and RIN in rats would interact with each other or be affected by other components in Yizhi. The rationality of the compatibility of Uncaria and Gastrodia elata as a classic “herb pair” has been verified from the pharmacokinetic viewpoint.

Assessment of the differences in the phenolic composition and color characteristics of new strawberry (Fragaria x ananassa Duch.) cultivars by HPLC-MS and Imaging Tristimulus Colorimetry.

Science.gov (United States)

Fernández-Lara, Rebeca; Gordillo, Belén; Rodríguez-Pulido, Francisco J; Lourdes González-Miret, M; Del Villar-Martínez, Alma A; Dávila-Ortiz, Gloria; Heredia, Francisco J

2015-10-01

The phenolic composition (by HPLC-DAD-MS) and color characteristics (by Imaging Tristimulus Colorimetry) of four strawberry cultivars that have shown good climate adaptation to subtropical area (Nikte, Zamorana, Jacona and Pakal) have been assessed. 24 monomeric phenolics were identified, including 15 anthocyanins, 5 phenolic acids, 1 flavanol and 4 flavonols. Nikte and Zamorana showed the highest phenolic potential mainly due to their higher content of anthocyanins, while Pakal was richer in phenolic acids. Regarding color, Nikte and Zamorana were the more similar cultivars having the lowest values of lightness and hue. On the contrary, the color of Pakal was quite different from all the rest, due to the specific distribution between pelargonidin and cyanidin. The inclusion of both phenolic and colorimetric information in the Linear Discriminant Analysis allowed reaching very good discriminations among cultivars. Copyright © 2015 Elsevier Ltd. All rights reserved.

Comparison of direct injection nebulizer and desolvating microconcentric nebulizer for analysis of chlorine-, bromine- and iodine-containing compounds by reversed phase HPLC with ICP-MS detection

DEFF Research Database (Denmark)

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

2003-01-01

the direct injection nebulizer at flow rates of 25 and 50 mul min(-1), the influence of 0-50% methanol and 0-25% acetonitrile on the sensitivity was studied. For chlorine and bromine, the relative sensitivity decreased with increasing amounts of organic solvent. For iodine, the relative sensitivity reached...... structure. Many chlorine-, bromine-, and iodine-containing compounds were partially lost in the desolvating unit. For those chlorine- and iodine-containing compounds that were not lost, the sensitivity was independent of methanol concentration in the solvent when a 0-100% methanol gradient was applied......With the purpose of finding ways to combine micro-bore reversed phase HPLC with ICP-MS detection for analysis of drug substances containing chlorine, bromine and iodine, the suitability of a direct injection nebulizer and an Aridus desolvating microconcentric nebulizer was compared. Using...

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

Energy Technology Data Exchange (ETDEWEB)

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

2000-10-01

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

Determination of reduced homocysteine in human serum by elemental labelling and liquid chromatography with ICP-MS and ESI-MS detection.

Science.gov (United States)

Espina, Juan Gómez; Montes-Bayón, Maria; Blanco-González, Elisa; Sanz-Medel, Alfredo

2015-10-01

Analytical methods allowing sensitive determination of reduced homocysteine (rHcy), one of the so-called biothiols, in human serum is a topic of growing interest due to its close relation to several human disorders, mainly cardiovascular diseases. Although most widely used analytical strategies to determine total Hcy involve derivatization by means of fluorescent labels, this work proposes the use of ebselen, a Se-containing labelling agent to derivatize the reactive sulfhydryl group of the Hcy molecule in its "free" reduced form, which is more likely to play different roles in disease pathogenesis. Optimization of the derivatization and separation conditions by high-performance liquid chromatography (HPLC) to isolate the excess of derivatizing reagent is carried out here using UV/VIS detection. Further, the study of the Se labelling reaction by electrospray ionization tandem mass spectrometry (ESI-MS/MS) provides a stoichiometry of the derivative of 1:1. The main advantage of using ebselen as a labelling agent is the presence of the Se atom in the molecule that allows the use of inductively coupled plasma mass spectrometry (ICP-MS) as a sensitive and selective Se detector. The coupling of HPLC with ICP-MS provided excellent features for the determination of Se-derivatized rHcy (detection limit of 9.6 nM) in real samples. Quantification was accomplished by using post-column isotope dilution (ID) of Se in serum samples, after precipitation of the main serum proteins. Quantitative results for "free" rHcy turned out to be around 0.18-0.22 μM in serum samples from healthy individuals that could be directly analyzed without sample preconcentration.

Non-aqueous CE-MS of cinchona alkaloids - characterizationof a novel CE-ESI-MS interface

DEFF Research Database (Denmark)

Hansen, Frederik André; Hansen, Steen Honoré; Petersen, Nickolaj J.

We have recently in our group at the University of Copenhagen developed a robust and simple sheatless CE-ESI-MS interface (capillary electrophoresis – electrospray ionization-mass spectrometry). In this presentation the interface is characterized and compared with HPLC-MS for studying...... a submicron fracture in the capillary close the ESI tip. The fracture provides a zero dead volume and excellent conducting properties due to the large amount of ions in the electric double layer. Electric current exceeding the upper limit of CE instrumentation of up to 300 µA can easily be obtained....... Furthermore, the increased conductivity of the buffer in the fracture generates field free pumping of the analytes towards the ESI spray tip. In this study the device was used to analyze the four major alkaloids (diastereomeric pairs of quinine/quinidine and cinchonine/cinchonidine) in Cinchona bark samples...

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

Directory of Open Access Journals (Sweden)

Lian-Xian Guo

2018-04-01

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

A novel study of screening and confirmation of modafinil, adrafinil and their metabolite modafinilic acid under EI-GC-MS and ESI-LC-MS-MS ionization.

Science.gov (United States)

Dubey, S; Ahi, S; Reddy, I M; Kaur, T; Beotra, A; Jain, S

2009-12-01

Adrafinil and modafinil have received wide publicity and have become controversial in the sporting world when several athletes were discovered allegedly using these drugs as doping agents. By acknowledging the facts, the World Anti-Doping Agency (WADA) banned these drugs in sports since 2004. The present study explores the possibility of differentiating adrafinil and modafinil and their major metabolites under electron impact ionization in gas chromatograph-mass spectrometer (GC-MSD) and electrospray ionization in liquid chromatograph-mass spectrometer (LC-MS/MS) by studying the fragmentation pattern of these drugs. Adrafinil, modafinil and their major metabolite, modafinilic acid were analyzed on EI-GC-MSD and ESI-LC-MS/MS using various individual parameters on both the instruments. The analytical technique and equipment used in the analysis were an Agilent 6890N GC with 5973 mass selective detector for the GC-MSD analysis and an Agilent 1100 HPLC with API-3200 Triple quadrupole mass spectrometer for the LC-MS/MS analysis. Validation of both methods was performed using six replicates at different concentrations. The results show that adrafinil, modafinil and their major metabolite modafinilic acid could be detected as a single artifact without differentiation under EI-GC-MSD analysis. However, all drugs could be detected and differentiated under ESI-LCMS/MS analysis without any artifaction. The GC-MSD analysis gives a single artifact for both the drugs without differentiation and thus can be used as a marker for screening purposes. Further, the Multiple Reaction Monitoring (MRM) method developed under LC-MS/MS is fit for the purpose for confirmation of suspicious samples in routine sports testing and in forensic and clinical analysis.

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

DEFF Research Database (Denmark)

Bendahl, L.; Gammelgaard, Bente

2004-01-01

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

Global metabolic profiling procedures for urine using UPLC-MS.

Science.gov (United States)

Want, Elizabeth J; Wilson, Ian D; Gika, Helen; Theodoridis, Georgios; Plumb, Robert S; Shockcor, John; Holmes, Elaine; Nicholson, Jeremy K

2010-06-01

The production of 'global' metabolite profiles involves measuring low molecular-weight metabolites (sample preparation, stability/storage and the selection of chromatographic conditions that balance metabolome coverage, chromatographic resolution and throughput. We discuss quality control and metabolite identification, as well as provide details of multivariate data analysis approaches for analyzing such MS data. Using this protocol, the analysis of a sample set in 96-well plate format, would take ca. 30 h, including 1 h for system setup, 1-2 h for sample preparation, 24 h for UPLC-MS analysis and 1-2 h for initial data processing. The use of UPLC-MS for metabolic profiling in this way is not faster than the conventional HPLC-based methods but, because of improved chromatographic performance, provides superior metabolome coverage.

HPLC-MS/MS method optimisation for matrix metalloproteinase 3 and matrix metalloproteinase 9 determination in human blood serum using target analysis.

Science.gov (United States)

Kotnik, Petra; Krajnc, Metka Koren; Pahor, Artur; Finšgar, Matjaž; Knez, Željko

2018-02-20

A quantitative analysis of zinc endopeptidases matrix metalloproteinase 9 (MMP9) and matrix metalloproteinase 3 (MMP3) from human blood serum are presented. Both matrix metalloproteinases (MMP) are present in human blood serum and can be used as biomarkers for different diseases. The analysis was performed using LC-MS/MS with a triple quadrupole mass spectrometer, based on two specific peptides of each MMP in comparison with an enzyme-linked immunosorbent assay (ELISA). While the conditions for the LC-MS/MS analysis of MMP9 peptides were previously reported for bronchoalveolar lavage fluid, the analysis of MMP3 peptides was newly quantified for human blood serum herein for the first time. For MMP3, the linear behaviour was determined in the concentration range from 1.0-200.0ng/mL (R 2 =0.997) with an LLOD of 0.5ng/mL. For MMP9, linearity was determined in the concentration range from 6.5-65.0ng/mL (R 2 =0.995) with an LLOD of 2.0ng/mL. Copyright © 2017 Elsevier B.V. All rights reserved.

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

Science.gov (United States)

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

2016-09-01

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

Identification and quantification of flavonoids and chromes in Baeckea frutescens by using HPLC coupled with diode-array detection and quadruple time-of-flight mass spectrometry.

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Jia, Bei-Xi; Huangfu, Qian-Qian; Ren, Feng-Xiao; Jia, Lu; Zhang, Yan-Bing; Liu, Hong-Min; Yang, Jie; Wang, Qiang

2015-01-01

This article marks the first report on high-performance liquid chromatography (HPLC) coupled with diode-array detection (DAD) and quadruple time-of-flight mass spectrometry (Q-TOF/MS) for the identification and quantification of main bioactive constituents in Baeckea frutescens. In total, 24 compounds were identified or tentatively characterised based on their retention behaviours, UV profiles and MS fragment information. Furthermore, a validated method with good linearity, sensitivity, precision, stability, repeatability and accuracy was successfully applied for simultaneous determination of five flavonoids and one chromone in different plant parts of B. frutescens collected at different harvest times, and their dynamic contents revealed the appropriate harvest times. The established HPLC-DAD-Q-TOF/MS using multi-bioactive markers was proved to be a validated strategy for the quality evaluation on both raw materials and related products of B. frutescens.

Determination of Scopolamine in Human Saliva Using Solid Phase Extraction and LC/MS/MS

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Wang, Zuwei; Vaksman, Zalman; Boyd, Jason; Putcha, Lakshmi

2007-01-01

Purpose: Scopolamine is the preferred treatment for motion sickness during space flight because of its quick onset of action, short half-life and favorable side-effect profile. The dose administered depends on the mode of administration and usually ranges between 0.1 and 0.8 mg. Such small doses make it difficult to detect concentrations of scopolamine in biological fluids by using conventional HPLC methods. To measure scopolamine in saliva and thereby to evaluate the pharmacokinetics of scopolamine, we developed an LC/MS/MS method using off-line solid phase extraction. Method: Samples (0.5mL) were loaded onto Waters Oasis HLB co-polymer cartridges (10 mg, 1 mL) and eluted with 0.5 mL methanol without evaporation and reconstitution. HPLC separation of the eluted sample was performed using an Agilent Zorbax SB-CN column (50 x 2.1 mm) at a flow rate of 0.2 mL/min for 4 minutes. The mobile phase for separation was 90:10 (v/v) methanol: ammonium acetate (2 mM) in water, pH 5.0 +/- 0.1. Concentrations of scopolamine were determined using a Micromass Quattro Micro(TM) mass spectrometer with electrospray ionization (ESI). ESI mass spectra were acquired in positive ion mode with multiple reaction monitoring for the determination of scopolamine m/z = 304.2 yields 138.1 and internal standard (IS) hyoscyamine m/z = 290.2 yields 124.1. Results: The method is rapid, reproducible, specific and has the following parameters: scopolamine and the IS are eluted at 1.7 and 3.2 min respectively. The linear range is 50-5000 pg/mL for scopolamine in saliva with correlation coefficients > 0.99 with a CV < 0.5 %. The intra-day and inter-day CVs are < 15 % for quality control samples with concentrations of 75, 300, 750 and 3000 pg/mL of scopolamine in human saliva. Conclusion: Solid phase extraction allows more rapid sample preparation and greater precision than liquid extraction. Furthermore, we increased the sensitivity and specificity by adjusting the LC mobile phase and using an MS/MS

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

Energy Technology Data Exchange (ETDEWEB)

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

2000-05-01

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

LC–UV/MS quality analytics of paediatric artemether formulations

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Kirsten Vandercruyssen

2014-02-01

Full Text Available A highly selective and stability-indicating HPLC-method, combined with appropriate sample preparation steps, is developed for β-artemether assay and profiling of related impurities, including possible degradants, in a complex powder for oral suspension. Following HPLC conditions allowed the required selectivity: a Prevail organic acid (OA column (250 mm×4.6 mm, 5 μm, flow rate set at 1.5 mL/min combined with a linear gradient (where A=25 mM phosphate buffer (pH 2.5, and B=acetonitrile from 30% to 75% B in a runtime of 60 min. Quantitative UV-detection was performed at 210 nm. Acetonitrile was applied as extraction solvent for sample preparation. Using acetonitrile–water mixtures as extraction solvent, a compartmental behaviour by a non-solving excipient-bound fraction and an artemether-solubilising free fraction of solvent was demonstrated, making a mobile phase based extraction not a good choice. Method validation showed that the developed HPLC-method is considered to be suitable for its intended regulatory stability-quality characterisation of β-artemether paediatric formulations. Furthermore, LC–MS on references as well as on stability samples was performed allowing identity confirmation of the β-artemether related impurities. MS-fragmentation scheme of β-artemether and its related substances is proposed, explaining the m/z values of the in-source fragments obtained. Keywords: Paediatric formulations, Sample preparation, Polar embedded organic acid column, Artemisinin trioxane derivatives, Related impurities and degradation compounds, MS-fragmentation

An Efficient Method for the Preparative Isolation and Purification of Flavonoid Glycosides and Caffeoylquinic Acid Derivatives from Leaves of Lonicera japonica Thunb. Using High Speed Counter-Current Chromatography (HSCCC) and Prep-HPLC Guided by DPPH-HPLC Experiments.

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Wang, Daijie; Du, Ning; Wen, Lei; Zhu, Heng; Liu, Feng; Wang, Xiao; Du, Jinhua; Li, Shengbo

2017-02-02

In this work, the n-butanol extract from leaves of Lonicera japonica Thunb. (L. japonica) was reacted with DPPH and subjected to a HPLC analysis for the guided screening antioxidants (DPPH-HPLC experiments). Then, nine antioxidants, including flavonoid glycosides and caffeoylquinic acid derivatives, were isolated and purified from leaves of L. japonica using high speed counter-current chromatography (HSCCC) and prep-HPLC. The n-butanol extract was firstly isolated by HSCCC using methyl tert-butyl ether/n-butanol/acetonitrile/water (0.5% acetic acid) (2:2:1:5, v/v), yielding five fractions F1, F2 (rhoifolin), F3 (luteoloside), F4 and F5 (collected from the column after the separation). The sub-fractions F1, F4 and F5 were successfully separated by prep-HPLC. Finally, nine compounds, including chlorogenic acid (1), lonicerin (2), rutin (3), rhoifolin (4), luteoloside (5), 3,4-Odicaffeoylquinic acid (6), hyperoside (7), 3,5-O-dicaffeoylquinic acid (8), and 4,5-O-dicaffeoylquinic acid (9) were obtained, respectively, with the purities over 94% as determined by HPLC. The structures were identified by electrospray ionization mass spectrometry (ESI-MS), 1H- and 13C-NMR. Antioxidant activities were tested, and the isolated compounds showed strong antioxidant activities.

HPLC-DAD-MS(n) characterisation of carotenoids from apricots and pumpkins for the evaluation of fruit product authenticity.

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Kurz, Christina; Carle, Reinhold; Schieber, Andreas

2008-09-15

Carotenoids including carotenoid esters from six apricot (Prunus armeniaca L.) cultivars and from eight cultivars from three pumpkin species (Cucurbita maxima Duch., Cucurbita pepo L., and Cucurbita moschata Duch.) were extracted without saponification, separated on a C-30 reversed-phase column and characterised by high-performance liquid chromatography/atmospheric pressure chemical ionisation-mass spectrometry (LC-MS). The predominant free carotenoids were quantified by HPLC with diode array detection. In contrast to previously published data, α-carotene could not be detected in apricots. Although the pumpkins showed significant differences in their free carotenoid profiles, major unesterified compounds different from those found in apricots could be determined. However, due to the natural heterogeneity, authentication of the apricot products cannot be accomplished exclusively using the profile of free carotenoids. Therefore, the investigations were extended to carotenoid esters. The xanthophyll ester profiles in pumpkins significantly differed from those in apricots in that the latter also contained both saturated and unsaturated fatty acids, whereas in pumpkins exclusively saturated fatty acids were detected. Admixtures of lower cost pumpkins could be detected in quantities of ⩾5% by increased contents of lutein and zeaxanthin, and by the appearance of antheraxanthin and α-carotene, respectively, depending on the added pumpkin cultivar, as well as the presence of characteristic lutein and antheraxanthin esters. However, pronounced differences in the carotenoid profiles of the investigated pumpkins and the partly minor amount of characteristic compounds lead to limitations of the detection of 5% level of admixture of pumpkin to apricot and of the method in general. Copyright © 2008 Elsevier Ltd. All rights reserved.

Comparison of the Trace Elements and Active Components of Lonicera japonica flos and Lonicera flos Using ICP-MS and HPLC-PDA.

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Zhao, Yueran; Dou, Deqiang; Guo, Yueqiu; Qi, Yue; Li, Jun; Jia, Dong

2018-06-01

Thirteen trace elements and active constituents of 40 batches of Lonicera japonica flos and Lonicera flos were comparatively studied using inductively coupled plasma mass-spectrometry (ICP-MS) and high-performance liquid chromatography-photodiode array (HPLC-PDA). The trace elements were 24 Mg, 52 Cr, 55 Mn, 57 Fe, 60 Ni, 63 Cu, 66 Zn, 75 As, 82 Se, 98 Mo, 114 Cd, 202 Hg, and 208 Pb, and the active compounds were chlorogenic acid, 3,5-O-dicaffeoylquinc acid, 4,5-O-dicaffeoylquinc acid, luteolin-7-O-glucoside, and 4-O-caffeoylquinic acid. The data of 18 variables were statistically processed using principal component analysis (PCA) and discriminate analysis (DA) to classify L. japonica flos and L. flos. The validated method was developed to divide the 40 samples into two groups based on the PCA in terms of 18 variables. Furthermore, the species of Lonicera was better discriminated by using DA with 12 variables. These results suggest that the method and statistical analysis of the contents of trace elements and chemical components can classify the L. japonica flos and L. flos using 12 variables, such as 3,5-O-dicaffeoylquincacid, luteolin-7-O-glucoside, Cd, Mn, Hg, Pb, Ni, 4-O-caffeoyl-quinic acid, 4,5-O-dicaffeoylquinc acid, Fe, Mg, and Cr.

Dynamic changes of flavonoids in Actinidia valvata leaves at different growing stages measured by HPLC-MS/MS.

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DU, Qiao-Hui; Zhang, Qiao-Yan; Han, Ting; Jiang, Yi-Ping; Peng, Cheng; Xin, Hai-Liang

2016-01-01

Flavonoids are a large group of phenolic secondary metabolites havinga wide range of biochemical and pharmacological effects. Quantitative analysis of flavonoid profiles in the genus Actinidia, which has not been intensively conducted, is useful to a better understanding of the pattern and distribution of flavonoids. In the present work, a liquid chromatography-electrospray ionization-tandem mass spectrometry (LC-ESI-MS/MS) method was developed to profile the flavonoids, which was then used to determine the dynamic change of 17 biologically active flavonoids in the leaves of Actinidia valvata at the main growing stages, including glucuronides and acylated di- and triglycosides of flavonoids. The contents of flavonoid triglycosides were significantly higher than other flavonoids. The highest concentrations of kaemperol glycosides were observed in June, while other flavonoids showed highest concentrations in October. On the other hand, the contents of four isorhamnetin glycosides were increased sharply in September to October. The flavonoid profiles seem to be related to temperature, UV-B, and water deficit. Further studies are required to examine the functions of flavonoids in the Actinidia valvata and the underlying molecular mechanisms of actions. Copyright © 2016 China Pharmaceutical University. Published by Elsevier B.V. All rights reserved.

HPLC-DAD-ESI-MS/MS analysis of fruits from Firmiana simplex (L.) and evaluation of their antioxidant and antigenotoxic properties.

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Ghareeb, Mosad Ahmed; Mohamed, Tamer; Saad, Amal Mohamed; Refahy, Laila Abdel-Ghany; Sobeh, Mansour; Wink, Michael

2018-01-01

The secondary metabolites of the fruits of Firmiana simplex (L.) were analysed by LC-DAD-ESI-MS/MS; furthermore, we evaluated their antioxidant and antigenotoxic properties. The antioxidant activity was investigated using the 2,2'-diphenyl-1-picrylhydrazyl radical (DPPH), the 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid) diammonium salt (ABTS) and the ferric reducing antioxidant power (FRAP) assays. The antigenotoxic potential was determined via the comet assay. The ethyl acetate fraction (EtOAc) was analysed by LC-DAD-ESI-MS/MS: phenolic acids and flavonoids were the main polyphenols of the fruits. The EtOAc fraction yielded the highest content of polyphenols with 314.61 mg GAE/g extract, followed by 297.51, 153.75, 101.47, 97.19 for dichloromethane, butanol, methanol and water extracts, respectively. As expected, a strong correlation exists between the antioxidant activity of the investigated extracts and their total phenolic content. In the DPPH assay, the IC 50 value of the most active EtOAc fraction was 6.79 μg/ml, relative to 2.92 μg/ml of the standard ascorbic acid. ABTS and FRAP assays supported the results of DPPH assay. Moreover, using the comet assay, we could show that the phenol-rich EtOAc extract exhibits an antigenotoxic potential in human liver cancer cells (Hep-G2) treated with hydrogen peroxide (H 2 O 2 ) as a genotoxic agent. The fruits of Firmiana simplex may be a good natural source of antioxidant and antigenotoxic agents. © 2017 Royal Pharmaceutical Society.

Development and validation of an HPLC/UV/MS method for simultaneous determination of 18 preservatives in grapefruit seed extract.

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Ganzera, Markus; Aberham, Anita; Stuppner, Hermann

2006-05-31

Grapefruit seed extracts are used in cosmetics, food supplements, and pesticides because of their antimicrobial properties, but suspicions about the true nature of the active compounds arose when synthetic disinfectants such as benzethonium or benzalkonium chloride were found in commercial products. The HPLC method presented herein allows the quality assessment (qualitative and quantitative) of these products for the first time. On the basis of a standard mixture of 18 preservatives most relevant for food and grapefruit products, a method was developed allowing the baseline separation of all compounds within 40 min. Optimum results were obtained with a C-8 stationary phase and a solvent system comprising aqueous trifluoroacetic acid, acetonitrile, and 2-propanol. The assay was fully validated and shown to be sensitive (LOD or = 96.1%), repeatable (sigma(rel) < or = 3.5%), precise (intra-day variation < or = 4.5%, interday variation < or = 4.1%), and rugged. Without any modifications the method could be adopted for LC-MS experiments, where the compounds of interest were directly assignable in positive ESI mode. The quantitative results of several products for ecofarming confirmed previous studies, as seven out of nine specimens were adulterated with preservatives in varying composition. The samples either contained benzethonium chloride (2.5-176.9 mg/mL) or benzalkonium chloride (138.2-236.3 mg/mL), together with smaller amounts of 4-hydroxybenzoic acid esters, benzoic acid, and salicylic acid.

Analysis of iridoids, secoiridoids and xanthones in Centaurium erythraea, Frasera caroliniensis and Gentiana lutea using LC-MS and RP-HPLC.

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Aberham, Anita; Pieri, Valerio; Croom, Edward M; Ellmerer, Ernst; Stuppner, Hermann

2011-02-20

This study presents a new and validated HPLC method for the simultaneous determination of bioactive compounds in Centaurium erythraea, Frasera caroliniensis and Gentiana lutea. The iridoid loganic acid, four secoiridoids and 29 xanthones were separated on a RP-18 column, using aqueous o-phosphoric acid (0.085%, v/v) and acetonitrile as mobile phase. Phytochemical investigation of C. erythraea herb and F. caroliniensis roots resulted into isolation of 25 xanthones and three secoiridoids the structure of which was elucidated by spectroscopic means (NMR, MS and UV). 1,3,8-Trihydroxy-5,6-dimethoxyxanthone, isolated from C. erythraea, turned out to be a novel xanthone. The stability of the analytes was tested by subjecting samples to light, moisture and different temperatures. After six months of storage, decomposition of gentiopicroside and sweroside was observed. The swertiamarin content was nearly unchanged when stored at room temperature or in the refrigerator, but high temperature conditions reduced the content to 85%. In contrast, xanthones were stable under long-term, refrigerated and accelerated conditions. The established chromatographic method has been successfully applied for the quantification of the bioactive compounds in the three plants. The presence and distribution of polyoxygenated xanthones within the three members of the Gentianaceae family and their significance as analytical markers are discussed. Copyright © 2010 Elsevier B.V. All rights reserved.

HPLC Determination and MS Confirmation of Malachite Green, Gentian Violet, and Their Leuco Metabolites in Catfish Muscle

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Residues of malachite green (MG), gentian violet (GV), and their leuco metabolites in catfish muscle were individually determined by HPLC using visible and fluorescence detectors. This detection scheme obviated a PbO2 column that converts leuco forms to chromatic forms for visible detection, thus el...

[HPLC Specific Fingerprint of Alcohol Extract of Andrographis paniculata].

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Liu, Fei-fei; Fan, Chun-lin; Huang, Xiao-jun; Wang, Gui-yang; Wang, Ying; Ye, Wen-cai

2015-07-01

To establish the specific fingerprint of alcohol extract of Andrographis paniculata by HPLC. The analysis was performed on Cosmosil 5C18 -MS-II (250 mm x 4. 6 mm, 5 µm) column, with gradient phase consisting of acetonitrile and water at the flow rate of 1. 0 mL/min. The UV detection wavelength was set at 225 nm, and column temperature was 30 °C. The specific fingerprint chromatogram was established and seven common peaks were identified by comparison with the reference standards and LC-MS. The relative retention times were 1. 00 (No. 1, andrographolide), 1. 04 (No. 2, deoxyandrographoside), 1. 07 (No. 3, isoandrographolide), 1. 10 (No. 4, 14-deoxy-11, 12-didehydroandrographoside), 1. 50 (No. 5, neoandrographolide), 1. 75 ( No. 6, deoxyandrographolide) and 1. 79 (No. 7, dehydroandrographolide). The method is simple and reproducible with high precision, which can provide the basis for the quality control and evaluation of alcohol extract of Andrographis paniculata and its preparations.

Identification and quantification of phenolic compounds of selected fruits from Madeira Island by HPLC-DAD-ESI-MS(n) and screening for their antioxidant activity.

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Spínola, Vítor; Pinto, Joana; Castilho, Paula C

2015-04-15

Five fruits species commonly cultivated and consumed in Madeira Island (Portugal) were investigated for their phenolic profile by means of reversed phase high-performance liquid chromatography coupled to diode array detection and electrospray ionisation mass spectrometry (HPLC-DAD-ESI/MS(n)) and antioxidant potential. A large number of compounds were characterised, flavonoids and phenolic acids being the major components found in target samples, 39 compounds (flavonoids, phenolic acids, terpenoids, cyanogenic glycosides and organic acids) were identified in cherimoyas, lemons, papayas, passion-fruits and strawberries for the first time. Furthermore, all samples were systematically analysed for their total phenolic and flavonoid contents along with two radical scavenging methods (ABTS and ORAC) for antioxidant activity measurement. Target fruits presented high phenolic contents which is responsible for most of the antioxidant activity against radical reactive species (R(2)>0.80). Quantitative data showed that anthocyanins, in particular pelargonidin-3-O-hexoside (>300 mg/100 mL), present only in strawberries were the compounds in largest amounts but are the ones which contribute less to the antioxidant activity. Copyright © 2014 Elsevier Ltd. All rights reserved.

An HPLC tandem mass spectrometry for quantification of ET-26-HCl and its major metabolite in plasma and application to a pharmacokinetic study in rats.

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Chen, Xu; Zhang, Wensheng; Rios, Sandy; Morkos, Miriam B; Ye, Xiaoli; Li, Gen; Jiang, Xuehua; Wang, Zhijun; Wang, Ling

2018-02-05

ET-26-HCl is a new analog of etomidate, a short-acting anesthetic drug, with less adrenal cortex inhibition. The pharmacokinetics of ET-26-HCl in rats needs to be determined for future clinical trials in human subjects. In order to facilitate the pharmacokinetic study, a liquid chromatography based tandem mass spectrometric (HPLC-MS/MS) method was developed and validated for quantification of ET-26-HCl and its major metabolite, ET-26-acid. These two compounds and gabapentin (internal standard) were extracted using a protein precipitation method with methanol and detected by Multiple Reaction Monitoring of m/z transition of 275.6-170.9, 217.7-113.1, and 172.5-154.3 for ET-26-HCl, ET-26-acid, and gabapentin respectively. This method was validated in terms of sensitivity, linearity, reproducibility, and stability. The HPLC-MS/MS method was found linear over the concentration ranges of 21.76-4352ng/mL, and 18.62-3724ng/mL with LLOQ of 21.76 and 18.62ng/mL for ET-26-HCl and ET-26-acid respectively. The mean intra-day and inter-day accuracy was between 94.11-107.78%, while the precision was within the limit of 15.0% for all the quality control samples. A pharmacokinetic study was then conducted in rats following intravenous injection of 2.1, 4.2, and 8.4mg/kg. The linear pharmacokinetics of ET-26-HCl was observed over the dose range of 2.1-8.4mg/kg. The average terminal phase elimination half-lives were 0.87 and 1.03h for ET-26-HCl and ET-26-acid respectively. In summary, an HPLC-MS/MS method for quantification of ET-26-HCl in rat plasma has been developed and successfully applied to a pharmacokinetic study. Copyright © 2017 Elsevier B.V. All rights reserved.

Exploring the Metabolism of (+-[18F]Flubatine In Vitro and In Vivo: LC-MS/MS Aided Identification of Radiometabolites in a Clinical PET Study †

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Friedrich-Alexander Ludwig

2018-02-01

Full Text Available Both (+-[18F]flubatine and its enantiomer (−-[18F]flubatine are radioligands for the neuroimaging of α4β2 nicotinic acetylcholine receptors (nAChRs by positron emission tomography (PET. In a clinical study in patients with early Alzheimer’s disease, (+-[18F]flubatine ((+-[18F]1 was examined regarding its metabolic fate, in particular by identification of degradation products detected in plasma and urine. The investigations included an in vivo study of (+-flubatine ((+-1 in pigs and structural elucidation of formed metabolites by LC-MS/MS. Incubations of (+-1 and (+-[18F]1 with human liver microsomes were performed to generate in vitro metabolites, as well as radiometabolites, which enabled an assignment of their structures by comparison of LC-MS/MS and radio-HPLC data. Plasma and urine samples taken after administration of (+-[18F]1 in humans were examined by radio-HPLC and, on the basis of results obtained in vitro and in vivo, formed radiometabolites were identified. In pigs, (+-1 was monohydroxylated at different sites of the azabicyclic ring system of the molecule. Additionally, one intermediate metabolite underwent glucuronidation, as also demonstrated in vitro. In humans, a fraction of 95.9 ± 1.9% (n = 10 of unchanged tracer remained in plasma, 30 min after injection. However, despite the low metabolic degradation, both radiometabolites formed in humans could be characterized as (i a product of C-hydroxylation at the azabicyclic ring system, and (ii a glucuronide conjugate of the precedingly-formed N8-hydroxylated (+-[18F]1.

Selective fishing and analysis of xanthine oxidase binders from two Fabaceae species by coupling enzyme functionalized core-shell magnetic nanoparticles with HPLC-MS.

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Liu, Liangliang; Shi, Shuyun; Zhao, Huading; Yu, Jingang; Jiang, Xinyu; Chen, Xiaoqing

2014-01-15

Xanthine oxidase (XOD) immobilized core-shell magnetic silica (Fe3O4@SiO2-XOD) nanoparticles coupled with high performance liquid chromatography-mass spectrometry (HPLC-MS) was developed to fish out and analyze XOD binders from two Fabaceae species, Puerariae lobata flower and Glycyrrhiza uralensis root. The prepared Fe3O4@SiO2-XOD nanoparticles exhibited good specificity for XOD binders, better dispersion in aqueous solution and reusability than those of Fe3O4-XOD nanoparticles. The amount of XOD immobilized onto Fe3O4@SiO2 nanoparticles was 339.9μg/mg and the activity of Fe3O4@SiO2-XOD nanoparticles remained 95% after ten times usage. The optimum conditions of selective fishing were optimized, and finally incubating pH was set at 7, incubating temperature at 25°C and adsorption time at 30min. Twelve XOD binders were successfully identified from ethyl acetate extract of P. lobata flower and G. uralensis root. The developed method provides a rapid, purposeful and effective way to identify active compounds from natural complex mixtures. Copyright © 2013 Elsevier B.V. All rights reserved.

Sesamin and sesamolin as unexpected contaminants in various cold-pressed plant oils: NP-HPLC/FLD/DAD and RP-UPLC-ESI/MS(n) study.

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Górnaś, Paweł; Siger, Aleksander; Pugajeva, Iveta; Segliņa, Dalija

2014-04-01

Thirteen cold-pressed oils (Japanese quince seed, black caraway, flaxseed, rapeseed, hemp, peanut, sunflower, pumpkin, hazelnut, poppy, walnut, almond and sesame oil) manufactured by the same company over a 2-year period (2011-12) were assessed for lipophilic compounds. The presence of sesamin and sesamolin, two characteristic lignans of sesame oil, were detected in all tested plant oils. Both lignans were identified by NP-HPLC/FLD/DAD and confirmed by a RP-UPLC-ESI/MS(n) method. The lowest amount of sesamin and sesamolin was found for Japanese quince seed oil (0.10 and 0.27 mg/100 g), and the highest, excluding sesame oil, for almond oil (36.21 and 105.42 mg/100 g, respectively). The highly significant correlation between sesamolin and sesamin concentrations was found in all samples tested (r = 0.9999; p products manufactured by the same company can contribute to a lesser regard for the quality of the final product. Moreover, less attention paid to the quality of final product can be related to the health risks of consumers especially sensitive to allergens. Therefore, proper cleaning of processing equipment is needed to prevent cross-contact of cold-pressed oils.

Characterisation of nucleosides and nucleobases in Mactra veneriformis by high performance liquid chromatography coupled with diode array detector-mass spectrometry (HPLC-DAD-MS).

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Liu, Rui; Ji, Jing; Wang, Lingchong; Chen, Shiyong; Guo, Sheng; Wu, Hao

2012-11-15

Mactra veneriformis has been used as sea food and traditional Chinese medicine (TCM) for thousands of years in China. In the present study, a high performance liquid chromatograph coupled with photodiode array detector and electrospray ionisation-mass spectrometer (HPLC-DAD-ESI-MS) method was established for detection of the nucleosides and nucleobases in M. veneriformis from four aquaticultural area of Jiangsu during different harvest time of one year. The validated method was successfully applied to identifying 10 nucleosides and nucleobases in 48 M. veneriformis samples. Quantitative analysis showed that nucleosides and nucleobases are rich in all M. veneriformis samples. However, their contents vary in different areas and harvest times. Principal component analysis (PCA) was used to classify the 48 samples based on the contents of the nucleosides and nucleobases. As a result, the samples could be mainly clustered into four groups, which was similar as aquaticultural areas classification. Based on the results, present method might be applicable for the quality control of M. veneriformis, or even other marine shellfish aquiculture and their products, and the quality of M. veneriformis might be more related with aquaticultural areas. Copyright © 2012 Elsevier Ltd. All rights reserved.

The use of HPLC-MS in T-cell epitope identification.

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Lemmel, Claudia; Stevanović, Stefan

2003-03-01

The hunt for T-cell epitopes is going on because hopes are set on such peptide sequences for diagnosis and vaccine development in the fight against infectious and tumor diseases. In addition to a variety of other techniques used in T-cell epitope identification, mass spectrometers coupled to microcapillary liquid chromatography have now become an important and sensitive tool in separation, detection, and sequence analysis of highly complex natural major histocompatibility complex (MHC) ligand mixtures. In this article, we review the basics of mass spectrometric techniques and their on-line coupling to microcapillary liquid chromatography (microcap-LC). Furthermore, we introduce current strategies for the identification of new T-cell epitopes using microcapillary liquid chromatography-mass spectrometry (microcap-LC-MS).

Simultaneous detection of water-soluble vitamins using the High Performance Liquid Chromatography (HPLC - a review

Directory of Open Access Journals (Sweden)

Rosemond Godbless Dadzie

2014-01-01

Full Text Available The water-soluble vitamins (WSV: ascorbic acid (vitamin C, thiamine (B1, riboflavin (B2, niacin (B3, panthothenic acid (B5, pyridoxine, and pyridoxal (B6, folic acid (B9, biotin(B8 , and B12 are very essential in the diet of humankind. As a result of ever increasing pressures from both consumers and legal enforcers, to specify accurately nutritive compositions of WSV that are present in food materials, many researchers have attempted to fill this niche through the provision of highly sensitive and rapid high performance liquid chromatography (HPLC procedures. In view of the health benefits of WSV, a replete of HPLC methods have been developed for simultaneous determination of their contents in nature and fortified food samples, nutritional supplements, as well as blood plasmas. The rate of losses of these vitamins during food processing and analysis, in addition to their transient dynamics, presents complexities in developing a highly sensitive HPLC procedure for their simultaneous separations and assays. This review critically assesses the different HPLC procedures developed by researchers and available in the open literature for simultaneous determination of water-soluble vitamins (WSV in dried tropical fruits materials. The study revealed that not a single chromatographic run developed by researchers can simultaneously elute all the WSV at a time. However, the HPLC procedures that are capable of determining all the WSV were coupled with electrospray ionization mass spectroscopy (ESI-MS, thus making the set-up expensive.

Determination of trace elements in high pure rare earth oxide by double focusing inductively coupled plasma mass spectrometry (HR ICP-MS) and high performance liquid chromatography (HPLC) techniques

International Nuclear Information System (INIS)

Pedreira Filho, Walter dos Reis

2000-01-01

Rare earth oxides are used in several technological fields whose applications can be observed in several areas of modern technology, among which are included: lasers, semiconductors semi, high purity materials and metallic alloys. The field of applications of the rare earth elements is quite wide. Several important industrial applications are ceramics, catalysts and metallurgical as well as research areas and high technology sectors. Such applications have been presenting an accentuated growth in the last years. Chemical characterization of rare earth oxides of high purity has been constituting one of the major challenges of analytical chemistry. Several analytical techniques were used for chemical characterization of high purity rare earth the oxides. Even so, those techniques present limitations when one needs to characterize materials of a high level of purity, as in the case of rare earth oxides. Some of those limitations are associated, for example, to spectral interference. Inductively Coupled Plasma Mass Spectrometry (ICP-MS) is a powerful analytical tool for quantitative analysis of metal impurities in high purity materials. The Instituto de Pesquisas Energeticas e Nucleares (IPEN) has an unit of production and purification of rare earth oxides, with above 99,9% level of purity. In this work, the rare earth impurities were characterized in samples (La 2 O 3 ; CeO 2 ; Pr 6 O 11 ; Nd 2 O 3 ; Sm 2 O 3 ; Gd 2 O 3 ; Y 2 O 3 ) produced at the IPEN and certified standard materials produced by Johnson Matthey Chemical (JMC). The technique of high performance liquid chromatography (HPLC) was used in the separation of the impurities. Quantification of metallic impurities was carried out as inductively coupled plasma mass spectrometer (HR-ICP MS). In this work it is presented a new analytical methodology in the chemical characterization of metallic impurities in rare earth oxides of high purity (> 99,9%) with and without separation of the matrix. Analyses of standard

The salivary proteome profile in patients affected by SAPHO syndrome characterized by a top-down RP-HPLC-ESI-MS platform.

Science.gov (United States)

Sanna, Monica; Firinu, Davide; Manconi, Paolo Emilio; Pisanu, Maria; Murgia, Giuseppe; Piras, Valentina; Castagnola, Massimo; Messana, Irene; del Giacco, Stefano Renato; Cabras, Tiziana

2015-06-01

SAPHO syndrome is a rare and often unrecognized disease with prominent inflammatory cutaneous and articular symptoms characterized by musculoskeletal manifestations (synovitis, hyperostosis, osteomyelitis) associated with dermatological conditions (severe acne and pustulosis). The acidic soluble fraction of whole saliva from 10 adult women affected by SAPHO syndrome and from a group of 28 healthy women was analysed by RP-HPLC-ESI-MS with the aim of discovering salivary biomarkers of the disorder. The levels of the oral proteins and peptides were correlated with clinical data. The following proteins showed a significant decreased concentration in saliva of SAPHO subjects with respect to controls: cystatin S1 and SN, histatins, the major acidic PRPs, P-C and P-B peptides. The cystatin SN abundance lowered according to the disease duration and histatins showed positive correlations with the C reactive protein. Statistical analysis performed excluding one patient with a different pattern of salivary proteins/peptides highlighted a positive relationship between cystatin S1, histatins 3, histatin 5, and the neutrophil count. Moreover, histatin 3 correlated positively with the total white cell count and negatively with the erythrocyte sedimentation rate. Levels and frequency of S100A12 protein showed a trend to increase in SAPHO patients. The high expression of this pro-inflammatory protein is probably related to the inflammatory response and to the altered neutrophil responses to functional stimuli that characterize SAPHO syndrome suggesting a possible application as a salivary biomarker.

Rapid measurement of plasma free fatty acid concentration and isotopic enrichment using LC/MS

Science.gov (United States)

Persson, Xuan-Mai T.; Błachnio-Zabielska, Agnieszka Urszula; Jensen, Michael D.

2010-01-01

Measurements of plasma free fatty acids (FFA) concentration and isotopic enrichment are commonly used to evaluate FFA metabolism. Until now, gas chromatography-combustion-isotope ratio mass spectrometry (GC/C/IRMS) was the best method to measure isotopic enrichment in the methyl derivatives of 13C-labeled fatty acids. Although IRMS is excellent for analyzing enrichment, it requires time-consuming derivatization steps and is not optimal for measuring FFA concentrations. We developed a new, rapid, and reliable method for simultaneous quantification of 13C-labeled fatty acids in plasma using high-performance liquid chromatography-mass spectrometry (HPLC/MS). This method involves a very quick Dole extraction procedure and direct injection of the samples on the HPLC system. After chromatographic separation, the samples are directed to the mass spectrometer for electrospray ionization (ESI) and analysis in the negative mode using single ion monitoring. By employing equipment with two columns connected parallel to a mass spectrometer, we can double the throughput to the mass spectrometer, reducing the analysis time per sample to 5 min. Palmitate flux measured using this approach agreed well with the GC/C/IRMS method. This HPLC/MS method provides accurate and precise measures of FFA concentration and enrichment. PMID:20526002

Determination of two progestin metabolites (17α-hydroxypregnanolone and pregnanediol) and different classes of steroids (androgens, estrogens, corticosteroids, progestins) in rivers and wastewaters by high-performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS).

Science.gov (United States)

Zhang, Kun; Fent, Karl

2018-01-01

A highly sensitive and robust method was developed for routine analysis of two progestin metabolites, 17α-hydroxypregnanolone (17OH-Δ5P) and pregnanediol (PD), and 31 other natural and synthetic steroids and related metabolites (estrogens, androgens, corticosteroids, progestins) in river water, as well as influents and effluents of municipal wastewater treatment plants (WWTP) using HPLC-MS/MS combined with solid-phase extraction. For the various matrixes considered, the optimized method showed satisfactory performance with recoveries of 70-120% for most of target steroids. The method detection limits (MDLs) ranged from 0.01 to 3ng/L for river water, 0.02 to 10ng/L for WWTP effluents, and 0.1 to 40ng/L for influents with good linearity and reproducibility. The developed method was successfully applied for the analysis of steroids in rivers and WWTP influent and effluents. WWTP influents concentrations of 17OH-Δ5P and PD were 51-256ng/L and up to 400ng/L, respectively, along with androstenedione (concentration range: 38-220ng/L), testosterone (11-26ng/L), estrone (2.3-37ng/L), 17β-estradiol (N.D.-8.7ng/L), 17α-hydroxyprogesterone (N.D.-66ng/L), medroxyprogesterone acetate (N.D.-5.3ng/L), and progesterone (2.0-22ng/L), while only androstenedione (ADD), estrone (E1), and estriol (E3) were detected in effluent with concentrations ranging up to 1.7ng/L, 0.90ng/L and 0.8ng/L, respectively. In river water samples, only ADD and E1 were detected with concentrations up to 1.0ng/L and 0.91ng/L. Our procedure represents the first method for analyzing 17OH-Δ5P and PD in environmental samples along with a large series of steroids. Copyright © 2017 Elsevier B.V. All rights reserved.

Differentiation of Cuscuta chinensis and Cuscuta australis by HPLC-DAD-MS analysis and HPLC-UV quantitation.

Science.gov (United States)

He, Xianghui; Yang, Wenzhi; Ye, Min; Wang, Qing; Guo, Dean

2011-11-01

Cuscuta chinensis and Cuscuta australis, the two botanical sources of the Chinese herbal medicine Tu-Si-Zi, were distinguished from each other based on qualitative and quantitative chemical analysis. By HPLC‑DAD‑MS, a total of 36 compounds were characterized from these two Cuscuta species, including 14 flavonoids, 17 quinic acid derivatives, and 5 lignans. In addition, HPLC‑UV was applied to determine seven major compounds (6 flavonoids plus chlorogenic acid) in 27 batches of Tu-Si-Zi. The results revealed that the amounts of the three classes of compounds varied significantly between the species. C. australis contained more flavonoids but less quinic acid derivatives and lignans than C. chinensis. Particularly, the amounts of kaempferol and astragalin in C. australis were remarkably higher than in C. chinensis. This finding could be valuable for the quality control of Tu-Si-Zi. © Georg Thieme Verlag KG Stuttgart · New York.

Simultaneous analysis of multiple classes of antimicrobials in environmental water samples using SPE coupled with UHPLC-ESI-MS/MS and isotope dilution.

Science.gov (United States)

Tran, Ngoc Han; Chen, Hongjie; Do, Thanh Van; Reinhard, Martin; Ngo, Huu Hao; He, Yiliang; Gin, Karina Yew-Hoong

2016-10-01

A robust and sensitive analytical method was developed for the simultaneous analysis of 21 target antimicrobials in different environmental water samples. Both single SPE and tandem SPE cartridge systems were investigated to simultaneously extract multiple classes of antimicrobials. Experimental results showed that good extraction efficiencies (84.5-105.6%) were observed for the vast majority of the target analytes when extraction was performed using the tandem SPE cartridge (SB+HR-X) system under an extraction pH of 3.0. HPLC-MS/MS parameters were optimized for simultaneous analysis of all the target analytes in a single injection. Quantification of target antimicrobials in water samples was accomplished using 15 isotopically labeled internal standards (ILISs), which allowed the efficient compensation of the losses of target analytes during sample preparation and correction of matrix effects during UHPLC-MS/MS as well as instrument fluctuations in MS/MS signal intensity. Method quantification limit (MQL) for most target analytes based on SPE was below 5ng/L for surface waters, 10ng/L for treated wastewater effluents, and 15ng/L for raw wastewater. The method was successfully applied to detect and quantify the occurrence of the target analytes in raw influent, treated effluent and surface water samples. Copyright © 2016 Elsevier B.V. All rights reserved.

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

Energy Technology Data Exchange (ETDEWEB)

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

2005-04-01

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

Separation and Simultaneous Determination of 14 Fungicides with the Combination of Multi-Analyte Methods and HPLC Detection

Energy Technology Data Exchange (ETDEWEB)

Canping, Pan [Department of Applied Chemistry, China Agricultural University, Beijing (China)

2009-07-15

The separation and simultaneous HPLC-MS determination for a series of fungicide products is reported. Multi-analyte methods were applied on a Chromolith RP-18e monolithic column having low resistance and enabling high flow rates and short analysis time at very good separation power. Details and analytical conditions are described with chromatograms illustrating the results and work done. (author)

Modifications of the acidic soluble salivary proteome in human children from birth to the age of 48months investigated by a top-down HPLC-ESI-MS platform.

Science.gov (United States)

Manconi, B; Cabras, T; Pisano, E; Sanna, M T; Olianas, A; Fanos, V; Faa, G; Nemolato, S; Iavarone, F; Castagnola, M; Messana, I

2013-10-08

During the first year of life the infant oral environment undergoes dramatic changes. To investigate how the salivary proteome of human children evolves during infant development we have analyzed whole saliva of 88 children aged between 0 and 48months by a top-down platform based on RP-HPLC-ESI-MS. Children were divided according to their age into five groups (A, 0-6months, N=17; B, 7-12months, N=14; C, 13-24months, N=32; D, 25-36months, N=16; E, 37-48months, N=9). The proteins and peptides analyzed were histatins (histatin-1, histatin-3 1/24), acidic proline-rich proteins, statherin, P-B peptide, and salivary cystatins. Protein and peptide quantification based on the area of the RP-HPLC-ESI-MS extracted ion current peak evidenced that: (i) concentrations of the major salivary proteins/peptides showed a minimum in the 0-6-month-old group and increased with age; (ii) the level of histatin-1 reached a maximum in the 7-12-month-old group, a minimum in the 13-24-month-aged babies and it increased again in the 25-36-month-old group; (iii) S-type cystatins were almost undetectable in the 0-6-month-old group; (iv) P-B peptide concentration greatly increased with age; (v) histatin-3 1/24 and statherin concentrations did not show any age-related variation. The top-down proteomic approach undertaken in this work reveals that the salivary proteome of human children from birth to 48months of age shows important quantitative modifications. The concentrations of the major salivary proteins, with the exception of statherin and histatin-3 1/24, showed a minimum in the 0-6-month-old group when the expression in salivary glands is probably not fully activated. Concentrations of the salivary proteins slowly increased with age, with different trends. Only histatin-1 showed the highest concentration in the 7-12-month-old group, followed by a decrease in the 13-24-month-aged children. This particular trend could be related to the phenomenon of eruption of primary dentition. This study

Xanthophylls in commercial egg yolks: quantification and identification by HPLC and LC-(APCI)MS using a C30 phase.

Science.gov (United States)

Schlatterer, Jörg; Breithaupt, Dietmar E

2006-03-22

The xanthophylls lutein and zeaxanthin have attracted a lot of interest since it was presumed that an increased nutritional uptake may prevent adult macula degeneration (AMD). Although egg yolks serve as an important dietary source of lutein and zeaxanthin, data on xanthophyll concentrations in commercial egg yolks are not available. Thus, an high-performance liquid chromatography-diode array detector (HPLC-DAD) method was developed allowing for simultaneous separation of eight xanthophylls used to fortify poultry feed. Peak identification was carried out by liquid chromatography-atmospheric pressure chemical ionization mass spectrometry [LC-(APCI)MS]. Egg yolks of four types of husbandry (seven batches each) were examined. Lutein and zeaxanthin were the predominant xanthophylls in egg yolks produced in accordance with ecological husbandry (class 0) because the concentrations of these xanthophylls ranged from 1274 to 2478 microg/100 g and from 775 to 1288 microg/100 g, respectively. Analysis of variance (ANOVA) proved that both mean lutein and mean zeaxanthin concentrations of eggs from class 0 were statistically discriminable from mean lutein and zeaxanthin concentrations from eggs of all other classes (P xanthophylls in eggs of classes 1 (free range), 2 (barn), and 3 (cage) were as follows: canthaxanthin, 707 +/- 284 microg/100 g; beta-apo-8'-carotenoic acid ethyl ester, 639 +/- 391 microg/100 g; and citranaxanthin, 560 +/- 231 microg/100 g. Experiments with boiled eggs proved that beta-apo-8'-carotenoic acid ethyl ester was the xanthophyll with the highest stability, whereas lutein was degraded to the largest extent (loss of 19%). Detailed knowledge about the xanthophyll amounts in eggs is indispensable to calculate the human uptake.

[Amanitine determination as an example of peptide analysis in the biological samples with HPLC-MS technique].

Science.gov (United States)

Janus, Tomasz; Jasionowicz, Ewa; Potocka-Banaś, Barbara; Borowiak, Krzysztof

Routine toxicological analysis is mostly focused on the identification of non-organic and organic, chemically different compounds, but generally with low mass, usually not greater than 500–600 Da. Peptide compounds with atomic mass higher than 900 Da are a specific analytical group. Several dozen of them are highly-toxic substances well known in toxicological practice, for example mushroom toxin and animal venoms. In the paper the authors present an example of alpha-amanitin to explain the analytical problems and different original solutions in identifying peptides in urine samples with the use of the universal LC MS/MS procedure. The analyzed material was urine samples collected from patients with potential mushroom intoxication, routinely diagnosed for amanitin determination. Ultra filtration with centrifuge filter tubes (limited mass cutoff 3 kDa) was used. Filtrate fluid was directly injected on the chromatographic column and analyzed with a mass detector (MS/MS). The separation of peptides as organic, amphoteric compounds from biological material with the use of the SPE technique is well known but requires dedicated, specific columns. The presented paper proved that with the fast and simple ultra filtration technique amanitin can be effectively isolated from urine, and the procedure offers satisfactory sensitivity of detection and eliminates the influence of the biological matrix on analytical results. Another problem which had to be solved was the non-characteristic fragmentation of peptides in the MS/MS procedure providing non-selective chromatograms. It is possible to use higher collision energies in the analytical procedure, which results in more characteristic mass spectres, although it offers lower sensitivity. The ultra filtration technique as a procedure of sample preparation is effective for the isolation of amanitin from the biological matrix. The monitoring of selected mass corresponding to transition with the loss of water molecule offers

Separation and identification of phenolic compounds of extra virgin olive oil from Olea europaea L. by HPLC-DAD-SPE-NMR/MS. Identification of a new diastereoisomer of the aldehydic form of oleuropein aglycone.

Science.gov (United States)

Pérez-Trujillo, Míriam; Gómez-Caravaca, Ana María; Segura-Carretero, Antonio; Fernández-Gutiérrez, Alberto; Parella, Teodor

2010-08-25

The phenolic fraction of a monovarietal extra virgin olive oil (EVOO) from Olea europaea L. var. Cornezuelo was studied by the hyphenated HPLC-DAD-SPE-NMR/MS techniques. This survey led to the identification of 25 main compounds. One was identified as a new diastereoisomer of the aldehydic form of oleuropein aglycone (AOA) and characterized by 1D and 2D NMR techniques. The relative configuration of this new AOA was determined as 5R*,8S*,9S* on the basis of the results obtained from the combination of NOE experiments and Monte Carlo conformational search calculations. Assuming, as for the described diastereoisomers, that the new AOA comes from the natural oleuropein aglycone (OA), the absolute configuration was proposed as 5S,8R,9R.

Testing of complementarity of PDA and MS detectors using chromatographic fingerprinting of genuine and counterfeit samples containing sildenafil citrate.

Science.gov (United States)

Custers, Deborah; Krakowska, Barbara; De Beer, Jacques O; Courselle, Patricia; Daszykowski, Michal; Apers, Sandra; Deconinck, Eric

2016-02-01

Counterfeit medicines are a global threat to public health. High amounts enter the European market, which is why characterization of these products is a very important issue. In this study, a high-performance liquid chromatography-photodiode array (HPLC-PDA) and high-performance liquid chromatography-mass spectrometry (HPLC-MS) method were developed for the analysis of genuine Viagra®, generic products of Viagra®, and counterfeit samples in order to obtain different types of fingerprints. These data were included in the chemometric data analysis, aiming to test whether PDA and MS are complementary detection techniques. The MS data comprise both MS1 and MS2 fingerprints; the PDA data consist of fingerprints measured at three different wavelengths, i.e., 254, 270, and 290 nm, and all possible combinations of these wavelengths. First, it was verified if both groups of fingerprints can discriminate between genuine, generic, and counterfeit medicines separately; next, it was studied if the obtained results could be ameliorated by combining both fingerprint types. This data analysis showed that MS1 does not provide suitable classification models since several genuines and generics are classified as counterfeits and vice versa. However, when analyzing the MS1_MS2 data in combination with partial least squares-discriminant analysis (PLS-DA), a perfect discrimination was obtained. When only using data measured at 254 nm, good classification models can be obtained by k nearest neighbors (kNN) and soft independent modelling of class analogy (SIMCA), which might be interesting for the characterization of counterfeit drugs in developing countries. However, in general, the combination of PDA and MS data (254 nm_MS1) is preferred due to less classification errors between the genuines/generics and counterfeits compared to PDA and MS data separately.

Authenticity analysis of citrus essential oils by HPLC-UV-MS on oxygenated heterocyclic components

Directory of Open Access Journals (Sweden)

Hao Fan

2015-03-01

Full Text Available Citrus essential oils are widely applied in food industry as the backbone of citrus flavors. Unfortunately, due to relatively simple chemical composition and tremendous price differences among citrus species, adulteration has been plaguing the industry since its inception. Skilled blenders are capable of making blends that are almost indistinguishable from authentic oils through conventional gas chromatography analysis. A reversed-phase high performance liquid chromatography (HPLC method was developed for compositional study of nonvolatile constituents in essential oils from major citrus species. The nonvolatile oxygenated heterocyclic components identified in citrus oils were proved to be more effective as markers in adulteration detection than the volatile components. Authors are hoping such an analysis procedure can be served as a routine quality control test for authenticity evaluation in citrus essential oils.

Brewer's Yeast as a New Source of Palmitoleic Acid-Analysis of Triacylglycerols by LC-MS

Czech Academy of Sciences Publication Activity Database

Řezanka, Tomáš; Matoulková, D.; Kolouchová, I.; Masák, J.; Sigler, Karel

2013-01-01

Roč. 90, č. 9 (2013), s. 1327-1342 ISSN 0003-021X R&D Projects: GA ČR(CZ) GAP503/11/0215 Institutional support: RVO:61388971 Keywords : Saccharomyces cerevisiae * Saccharomyces pastorianus * RP-HPLC/MS-APCI Subject RIV: EE - Microbiology, Virology Impact factor: 1.620, year: 2013

Quantitative and qualitative analysis of the novel antitumor 1,3,4-oxadiazole derivative (GLB) and its metabolites using HPLC-UV and UPLC-QTOF-MS

Science.gov (United States)

Li, Pu; Wang, Xin; Li, Jian; Meng, Zhi-Yun; Li, Shu-Chun; Li, Zhong-Jun; Lu, Ying-Yuan; Ren, Hong; Lou, Ya-Qing; Lu, Chuang; Dou, Gui-Fang; Zhang, Guo-Liang

2015-01-01

Fructose-based 3-acetyl-2,3-dihydro-1,3,4-oxadiazole (GLB) is a novel antitumor agent and belongs to glycosylated spiro-heterocyclic oxadiazole scaffold derivative. This research first reported a simple, specific, sensitive and stable high performance liquid chromatography -ultraviolet detector (HPLC-UV) method for the quantitative determination of GLB in plasma. In this method, the chromatographic separation was achieved with a reversed phase C18 column. The calibration curve for GLB was linear at 300 nm. The lower limit of quantification was 10 ng/mL. The precision, accuracy and stability of the method were validated adequately. This method was successfully applied to the pharmacokinetic study in rats for detection of GLB after oral administration. Moreover, the structures of parent compound GLB and its two major metabolites M1 and M2 were identified in plasma using an ultra performance liquid chromatography- electrospray ionization-quadrupole-time of flight- mass spectrometry (UPLC-ESI-QTOF-MS) method. Our results indicated that the di-hydroxylation (M1) and hydroxylation (M2) of GLB are the major metabolites. In conclusion, the present study provided valuable information on an analytical method for the determination of GLB and its metabolites in rats, can be used to support further developing of this antitumor agent. PMID:26148672

Quality control and identification of steroid saponins in crude extracts from Dioscorea zingiberensis C. H. Wright by fingerprint with HPLC-ELSD and HPLC-ESI-Quadrupole/Time-of-fight tandem mass spectrometry

Science.gov (United States)

Zhang, Xinxin; Liang, Jinru; Liu, Jianli; Zhao, Ye; Gao, Juan; Sun, Wenji; Ito, Yoichiro

2014-01-01

In this study, a fingerprint of steroid saponins, the major bioactive constituents in the crude extracts from Dioscorea zingiberensis C. H. Wright (DZW), has been established for the first time by high-performance liquid chromatography coupled with evaporative light scattering detector (HPLC-ELSD) and the simultaneous characterization of the steroid saponins by high-performance liquid chromatography coupled with electrospray ionization-mass spectrometry and quadrupole tandem time-of-fight mass analyzers detection (HPLC-ESI-Q/TOF). These HPLC analyses were both carried out on a Welchrom C18 column (250 mm × 4.6 mm I.D., 5 μm) with a mobile phase composed of water and acetonitrile under gradient elution. There were 68 common characteristic peaks in the fingerprints, in which 12 of them were confirmed by comparing their mass spectra and retention times with those of the reference compounds. In order to identify the other unknown peaks, their fragmentation behaviors characteristic for the major groups of steroid saponins from DZW with six types of aglycone skeletons were discussed in detail, and possible MS/MS fragmentation pathways were proposed for aiding the structural identification of these components. According to the summarized fragmentation patterns, these peaks were tentatively assigned by matching their empirical molecular formula with those of the published compounds, or by elucidating their quasi-molecular ions and fragment ions referring to available literature information when the reference standards were unavailable. As a result, 22 steroid saponins were found in DZW for the first time. In addition, the quantitative analysis of the 12 known peaks was accomplished at the same time which indicated that there was a great variability in the amount of these active compounds in different batches in the crude extracts. This approach could demonstrate that the fingerprint could be considered to be a suitable tool to comprehensively improve the quality control

Synthesis of (±-3,4-dimethoxybenzyl-4-methyloctanoate as a novel internal standard for capsinoid determination by HPLC-ESI-MS/MS(QTOF

Directory of Open Access Journals (Sweden)

Fayos O

2018-02-01

Full Text Available Capsinoids exhibit health-promoting properties and are therefore compounds of interest for medical and food sciences. They are minor compounds present in relatively high concentrations in only a few number of pepper cultivars. It is desirable to quantify capsinoids to provide selected cultivars with high capsinoid contents, which can then be employed as health food product. Quantifying low concentrations of capsinoids from pepper fruit requires a precise and selective analytical technique such as HPLC coupled to electrospray ionization - mass spectrometry, with development of an internal standard essential. In this work, the synthesis method of a novel compound analogue of capsinoids, the (±-3,4-dimethoxybenzyl-4-methyloctanoate, which could be a suitable internal standard for capsinoid determination by electrospray ionization - mass spectrometry is described.

Analysis of pharmaceutical impurities using multi-heartcutting 2D LC coupled with UV-charged aerosol MS detection.

Science.gov (United States)

Zhang, Kelly; Li, Yi; Tsang, Midco; Chetwyn, Nik P

2013-09-01

To overcome challenges in HPLC impurity analysis of pharmaceuticals, we developed an automated online multi-heartcutting 2D HPLC system with hyphenated UV-charged aerosol MS detection. The first dimension has a primary column and the second dimension has six orthogonal columns to enhance flexibility and selectivity. The two dimensions were interfaced by a pair of switching valves equipped with six trapping loops that allow multi-heartcutting of peaks of interest in the first dimension and also allow "peak parking." The hyphenated UV-charged aerosol MS detection provides comprehensive detection for compounds with and without UV chromophores, organics, and inorganics. It also provides structural information for impurity identification. A hidden degradation product that co-eluted with the drug main peak was revealed by RP × RP separation and thus enabled the stability-indicating method development. A poorly retained polar component with no UV chromophores was analyzed by RP × hydrophilic interaction liquid chromatography separation with charged aerosol detection. Furthermore, using this system, the structures of low-level impurities separated by a method using nonvolatile phosphate buffer were identified and tracked by MS in the second dimension. © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

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

Science.gov (United States)

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

2015-01-01

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

Forensic Drug Identification, Confirmation, and Quantification Using Fully Integrated Gas Chromatography with Fourier Transform Infrared and Mass Spectrometric Detection (GC-FT-IR-MS).

Science.gov (United States)

Lanzarotta, Adam; Lorenz, Lisa; Voelker, Sarah; Falconer, Travis M; Batson, JaCinta S

2018-05-01

This manuscript is a continuation of a recent study that described the use of fully integrated gas chromatography with direct deposition Fourier transform infrared detection and mass spectrometric detection (GC-FT-IR-MS) to identify and confirm the presence of sibutramine and AB-FUBINACA. The purpose of the current study was to employ the GC-FT-IR portion of the same instrument to quantify these compounds, thereby demonstrating the ability to identify, confirm, and quantify drug substances using a single GC-FT-IR-MS unit. The performance of the instrument was evaluated by comparing quantitative analytical figures of merit to those measured using an established, widely employed method for quantifying drug substances, high performance liquid chromatography with ultraviolet detection (HPLC-UV). The results demonstrated that GC-FT-IR was outperformed by HPLC-UV with regard to sensitivity, precision, and linear dynamic range (LDR). However, sibutramine and AB-FUBINACA concentrations measured using GC-FT-IR were not significantly different at the 95% confidence interval compared to those measured using HPLC-UV, which demonstrates promise for using GC-FT-IR as a semi-quantitative tool at the very least. The most significant advantage of GC-FT-IR compared to HPLC-UV is selectivity; a higher level of confidence regarding the identity of the analyte being quantified is achieved using GC-FT-IR. Additional advantages of using a single GC-FT-IR-MS instrument for identification, confirmation, and quantification are efficiency, increased sample throughput, decreased consumption of laboratory resources (solvents, chemicals, consumables, etc.), and thus cost.

Quantitative and Qualitative Analysis of Flavonoids and Phenolic Acids in Snow Chrysanthemum (Coreopsis tinctoria Nutt.) by HPLC-DAD and UPLC-ESI-QTOF-MS.

Science.gov (United States)

Yang, Yinjun; Sun, Xinguang; Liu, Jinjun; Kang, Liping; Chen, Sibao; Ma, Baiping; Guo, Baolin

2016-09-30

A simple, accurate and reliable high performance liquid chromatography coupled with photodiode array detection (HPLC-DAD) method was developed and then successfully applied for simultaneous quantitative analysis of eight compounds, including chlorogenic acid ( 1 ), ( R / S )-flavanomarein ( 2 ), butin-7- O -β-d-glucopyranoside ( 3 ), isookanin ( 4 ), taxifolin ( 5 ), 5,7,3',5'-tetrahydroxyflavanone-7- O -β-d-glucopyranoside ( 6 ), marein ( 7 ) and okanin ( 8 ), in 23 batches of snow chrysanthemum of different seed provenance and from various habitats. The results showed total contents of the eight compounds in the samples with seed provenance from Keliyang (Xinjiang, China), are higher than in samples from the other five provenances by 52.47%, 15.53%, 19.78%, 21.17% and 5.06%, respectively, which demonstrated that provenance has a great influence on the constituents in snow chrysanthemum. Meanwhile, an ultra performance liquid chromatography coupled with electrospray ionization and quadrupole time-of-flight-mass spectrometry (UPLC-ESI-QTOF-MS) was also employed to rapidly separate and identify flavonoids and phenolic acids in snow chrysanthemum from Keliyang. As a result, a total of 30 constituents, including 26 flavonoids and four phenolic acids, were identified or tentatively identified based on the exact mass information, the fragmentation characteristics, and retention times of eight reference standards. This work may provide an efficient approach to comprehensively evaluate the quality of snow chrysanthemum.

Quantitative and Qualitative Analysis of Flavonoids and Phenolic Acids in Snow Chrysanthemum (Coreopsis tinctoria Nutt. by HPLC-DAD and UPLC-ESI-QTOF-MS

Directory of Open Access Journals (Sweden)

Yinjun Yang

2016-09-01

Full Text Available A simple, accurate and reliable high performance liquid chromatography coupled with photodiode array detection (HPLC-DAD method was developed and then successfully applied for simultaneous quantitative analysis of eight compounds, including chlorogenic acid (1, (R/S-flavanomarein (2, butin-7-O-β-d-glucopyranoside (3, isookanin (4, taxifolin (5, 5,7,3′,5′-tetrahydroxyflavanone-7-O-β-d-glucopyranoside (6, marein (7 and okanin (8, in 23 batches of snow chrysanthemum of different seed provenance and from various habitats. The results showed total contents of the eight compounds in the samples with seed provenance from Keliyang (Xinjiang, China, are higher than in samples from the other five provenances by 52.47%, 15.53%, 19.78%, 21.17% and 5.06%, respectively, which demonstrated that provenance has a great influence on the constituents in snow chrysanthemum. Meanwhile, an ultra performance liquid chromatography coupled with electrospray ionization and quadrupole time-of-flight-mass spectrometry (UPLC-ESI-QTOF-MS was also employed to rapidly separate and identify flavonoids and phenolic acids in snow chrysanthemum from Keliyang. As a result, a total of 30 constituents, including 26 flavonoids and four phenolic acids, were identified or tentatively identified based on the exact mass information, the fragmentation characteristics, and retention times of eight reference standards. This work may provide an efficient approach to comprehensively evaluate the quality of snow chrysanthemum.

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

DEFF Research Database (Denmark)

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

2003-01-01

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

Acquisition of HPLC-Mass Spectrometer

Science.gov (United States)

2015-08-18

31-Jan-2015 Approved for Public Release; Distribution Unlimited Final Report: Acquisition of HPLC -Mass Spectrometer The views, opinions and/or findings...published in peer-reviewed journals: Final Report: Acquisition of HPLC -Mass Spectrometer Report Title The acquisition of the mass spectrometer has been a

Determination of 25-OCH3-PPD and the related substances by UPLC-MS/MS and their cytotoxic activity.

Science.gov (United States)

Ding, Meng; Lu, Jingjing; Zhao, Chen; Zhang, Sainan; Zhao, Yuqing

2016-06-01

20(R)-25-methoxyl-dammarane-3β,12β,20-triol (25-OCH3-PPD) is a promising antitumor compound belonging to triterpenoid saponins isolated from radix notoginseng. A systematic research on the related impurities in raw material of 25-OCH3-PPD has not been conducted. In this study, three impurities obtained by HPLC-ELSD and characterized by (13)C NMR and MS were observed in the raw material of 25-OCH3-PPD. Cytotoxic activities of the related substances were also evaluated, of which impurity B with 25-OCH3-PPD showed synergistic inhibitory activity against BGC-823 with IC50 values of 8.33μM. Furthermore, a rapid and selective UPLC-MS/MS method was developed for simultaneous determination of the principal component and three related substances in the raw material of 25-OCH3-PPD. Multiple reaction monitoring scan mode was used for the quantification of 20(R)-25-OCH3-PPD and its three related substances. The four constituents were separated within 11min on a BEH C18 column (100 mm×2.1mm, 1.7μm) using a mobile phase comprising methanol and 0.03% formic acid water (82:18, v/v) at a flow rate of 0.2mL/min. The proposed UPLC-MS/MS method displayed acceptable levels of linearity, precision, repeatability, and accuracy. In addition, the proposed method was successfully applied for the establishment of a rational quality control standard for the raw material of 25-OCH3-PPD. Copyright © 2016 Elsevier B.V. All rights reserved.

LC/MS study of the UV filter hexyl 2-[4-(diethylamino)-2-hydroxybenzoyl]-benzoate (DHHB) aquatic chlorination with sodium hypochlorite.

Science.gov (United States)

Grbović, G; Trebše, P; Dolenc, D; Lebedev, A T; Sarakha, M

2013-11-01

The fate of modern personal care products in the environment is becoming a matter of increasing concern because of the growing production and assortment of these compounds. More and more chemicals of this class are treated as emerging contaminants. Transformation of commercially available products in the environment may result in the formation of a wide array of their metabolites. Personal care products in swimming pools and in drinking water reservoirs may undergo oxidation or chlorination. There is much data on the formation of more toxic metabolites from original low toxicity commercial products. Therefore, reliable identification of all possible transformation products and a thorough study of their physicochemical and biological properties are of high priority. The present study deals with the identification of the products of the aquatic chlorination of the hexyl 2-[4-(diethylamino)-2-hydroxybenzoyl]-benzoate ultraviolet filter. High-performance liquid chromatography/mass spectrometry (HPLC/MS) and HPLC/MS/MS with accurate mass measurements were used for this purpose. As a result, three chlorinated transformation products were identified. Copyright © 2013 John Wiley & Sons, Ltd.

Comparison of Separation of Seed Oil Triglycerides Containing Isomeric Conjugated Octadecatrienoic Acid Moieties by Reversed-Phase HPLC

OpenAIRE

Anh Van Nguyen; Victor Deineka; Lumila Deineka; Anh Vu Thi Ngoc

2017-01-01

Relative retention analysis and increment approach were applied for the comparison of triglycerides (TGs) retention of a broad set of plant seed oils with isomeric conjugated octadecatrienoic acids (CLnA) by reversed-phase HPLC for “propanol-2-acetonitrile” mobile phases and Kromasil 100-5C18 stationary phase with diode array detection (DAD) and mass spectrometric (MS) detection. The subjects of investigation were TGs of seed oils: Calendula officinalis, Catalpa ovata, Jacaranda mimosifolia, ...

Psidium guajava L. leaves as source of proanthocyanidins: Optimization of the extraction method by RSM and study of the degree of polymerization by NP-HPLC-FLD-ESI-MS.

Science.gov (United States)

Díaz-de-Cerio, Elixabet; Pasini, Federica; Verardo, Vito; Fernández-Gutiérrez, Alberto; Segura-Carretero, Antonio; Caboni, Maria Fiorenza

2017-01-30

Due to the importance of the proanthocyanidins (PAs) bioactivity and its relationship with the PAs degree of polymerization (DP), an experimental design was carried out to establish the best extraction conditions in order to evaluate the proanthocyanidins content and their degree of polymerization in Psidium guajava leaves at different oxidation state. Optimal conditions achieved by response surface methodology were 50% acetone/water (v/v), 48°C, 30min, and 0% acetic acid (v/v). The highest DP has been found in the low oxidized state (DP 13 plus the polymers). Medium and high oxidized state leaves reported a DP 11 plus the polymers. The total amounts of proanthocyanidins (sum of PAs by HPLC-FLD-ESI-MS) decreased when oxidation state of leaves increased (15.8±0.4, 12.6±0.4, and 10.5±0.3mg/g leaf dry weight (d.w.) in low, medium and high oxidized state leaves, respectively). Guava leaves present an interesting source of low DP-PAs. Copyright © 2016 Elsevier B.V. All rights reserved.

Simultaneous determination of bioactive constituents in Danggui Buxue Tang for quality control by HPLC coupled with a diode array detector, an evaporative light scattering detector and mass spectrometry.

Science.gov (United States)

Yi, Ling; Qi, Lian-Wen; Li, Ping; Ma, Yi-Han; Luo, Yong-Jing; Li, Hai-Yun

2007-09-01

Danggui Buxue Tang (DBT), a classical traditional Chinese formula comprising Radix Angelicae Sinensis (RAS) and Radix Astragali (RA), has been widely used to treat menopausal irregularity in Chinese women for nearly 800 years. In this study, a comprehensive analytical method of simultaneously determining the main types of bioactive constituents, eighteen in all from the formula, involving flavonoids, saponins, organic acid and some volatile compounds, was developed. This method was based on HPLC coupled to a diode array and evaporative light scattering detectors (HPLC-DAD-ELSD) on a common reverse-phase C(18) column. Liquid chromatography coupled with on-line electrospray ionization mass spectrometry (LC-ESI-MS) was also used to further validate and analyze the constituents. It was found that 0.3% aqueous formic acid and acetonitrile was the optimum mobile phase for gradient elution. This method, which showed good precision and accuracy, was successfully used to quantify the bioactive constituents in six products. As a result, the validated HPLC method, together with the LC-ESI-MS analysis, provided a new basis for assessing the quality of traditional Chinese medicinal compound preparations (TCMCPs) consisting of many bioactive components.

Diagnostic fragment-ion-based and extension strategy coupled to DFIs intensity analysis for identification of chlorogenic acids isomers in Flos Lonicerae Japonicae by HPLC-ESI-MS(n).

Science.gov (United States)

Zhang, Jia-Yu; Zhang, Qian; Li, Ning; Wang, Zi-Jian; Lu, Jian-Qiu; Qiao, Yan-Jiang

2013-01-30

A method of modified diagnostic fragment-ion-based extension strategy (DFIBES) coupled to DFIs (diagnostic fragmentation ions) intensity analysis was successfully established to simultaneously screen and identify the chlorogenic acids (CGAs) in Flos Lonicerae Japonicae (FLJ) by HPLC-ESI-MS(n). DFIs, such as m/z 191 [quinic acid-H](-), m/z 179 [caffeic acid-H](-) and m/z 173 [quinic acid-H-H2O](-) were determined or proposed from the fragmentation patterns analysis of corresponding reference substances for every chemical family of CGAs. A "structure extension" method was then proposed based on the well-demonstrated fragmentation patterns and was successively applied into the rapid screening of CGAs in FLJ. Considering that substitution isomerism is a common phenomenon, a full ESI-MS(n) fragmentation analysis according to the intensity of DFIs has been performed to identify the CGA isomers. Based on the DFIs and intensity analysis, 41 peaks attributed to CGAs including 4 caffeoylquinic acids (CQA), 7 CQA glycosides, 6 dicaffeoylquinic acids (DiCQA), 10 DiCQA glycosides, 1 tricaffeoylquinic acids (TriCQA), 4p-coumaroylquinic acids (pCoQA), 3 feruloylquinic acids (FQA) and 6 caffeoylferuloylquinic acids (CFQA) were identified preliminarily in a 65-min chromatographic run. It was the first time to systematically report the presence of CGAs in FLJ, especially for CQA glycosides, DiCQA glycosides, TriCQA, pCoQA and CFQA. All the results indicated that the method of developed DFIBES coupled to DFIs analysis was feasible, reliable and universal for screening and identifying the constituents with the same carbon skeletons especially the isomeric compounds from the complex extract of TCMs. Copyright © 2012 Elsevier B.V. All rights reserved.

Identification of proteins from tuberculin purified protein derivative (PPD) by LC-MS/MS.

Science.gov (United States)

Borsuk, Sibele; Newcombe, Jane; Mendum, Tom A; Dellagostin, Odir A; McFadden, Johnjoe

2009-11-01

The tuberculin purified protein derivative (PPD) is a widely used diagnostic antigen for tuberculosis, however it is poorly defined. Most mycobacterial proteins are extensively denatured by the procedure employed in its preparation, which explains previous difficulties in identifying constituents from PPD to characterize their behaviour in B- and T-cell reactions. We here described a proteomics-based characterization of PPD from several different sources by LC-MS/MS, which combines the solute separation power of HPLC, with the detection power of a mass spectrometer. The technique is able to identify proteins from complex mixtures of peptide fragments. A total of 171 different proteins were identified among the four PPD samples (two bovine PPD and two avium PPD) from Brazil and UK. The majority of the proteins were cytoplasmic (77.9%) and involved in intermediary metabolism and respiration (24.25%) but there was a preponderance of proteins involved in lipid metabolism. We identified a group of 21 proteins that are present in both bovine PPD but were not detected in avium PPD preparation. In addition, four proteins found in bovine PPD are absent in Mycobacterium bovis BCG vaccine strain. This study provides a better understanding of the tuberculin PPD components leading to the identification of additional antigens useful as reagents for specific diagnosis of tuberculosis.

Simultaneous determination of telmisartan and amlodipine in dog plasma by LC-MS-MS.

Science.gov (United States)

Wang, Baolian; Sheng, Li; Li, Yan

2015-01-01

A simple, rapid and sensitive method was established for the simultaneous determination of telmisartan and amlodipine in dog plasma by a HPLC-MS-MS analysis. The plasma sample preparation was a simple deproteinization by the addition of three volumes of methanol/acetonitrile mixture followed by centrifugation. The analytes and internal standard diphenhydramine were separated on a Zorbax SB-C18 column with a mobile phase of acetonitrile : water (45 : 55, v/v) at a flow rate of 0.2 mL/min with an operating temperature of 25°C. Detection was carried out by electrospray ionization in positive-ion multiple reaction monitoring mode. The calibration plots in dog plasma were linear over the ranges of 0.5-2,000 ng/mL for telmisartan and 0.5-500 ng/mL for amlodipine. The lower limit of quantification was 0.5 ng/mL for two analytes. The intra- and interday precisions (RSD%) were within 9.0%. The average recoveries of analytes were >85.0%. The method was successfully applied to the pharmacokinetic study of the two compounds after oral administration of telmisartan-amlodipine combination preparation to dogs. © The Author 2015. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

Sensitive detectors in HPLC

International Nuclear Information System (INIS)

Anon.

1992-01-01

Detection of sample components in HPLC is difficult for many reasons; the key difficulty is the mobile phase which usually has properties similar to the solute. A variety of detectors have been developed for use in HPLC based on one of the above approaches; however, the search is still continuing for an ideal or universal detector. A universal detector should have the following characteristics: (1) responds to all solutes or has predictable specificity; (2) high detectability and the same predictable response; (3) fast response; (4) wide range of linearity; (5) unaffected by changes in temperature and mobile-phase flow; (6) responds independently of the mobile phase; (7) makes no contribution to extracolumn band broadening; (8) reliable and convenient to use; (9) nondestructive to the solute; (10) provides qualitative information on the detected peak. Unfortunately, no available HPLC detector possesses all these properties. 145 refs

HPLC: Early and Recent Perspectives.

Science.gov (United States)

Karger, Barry L.

1997-01-01

Provides a perspective on what it was like in the early days of high-performance liquid chromatography (HPLC) and several of the key developments. Focuses on the advances in HPLC generally, and more specifically for the biological sciences, that were necessary for the method to reach the preeminent stage of today. Contains 20 references. (JRH)

Comparison of polysaccharides of Haliotis discus hannai and Volutharpa ampullacea perryi by PMP-HPLC-MS(n) analysis upon acid hydrolysis.

Science.gov (United States)

Wang, Hongxu; Zhao, Jun; Li, Dongmei; Wen, Chengrong; Liu, Haiman; Song, Shuang; Zhu, Beiwei

2015-10-13

Haliotis discus hannai Ino (Haliotis) is a highly valued marine shellfish, and it is sometimes replaced by another cheaper Gastropoda mollusk, Volutharpa ampullacea perryi (Volutharpa). Polysaccharides from pleopods, viscera and gonads of these two gastropods were compared by analyzing the mono- and di-saccharides in their acid hydrolysates using high performance liquid chromatography-mass spectrometry (HPLC-MS(n)) after 1-phenyl-3-methyl-5-pyrazolone (PMP) derivatization. Disaccharide analysis revealed the distribution of uronic acid-containing polysaccharides (UACPs) in the biological samples. GlcA-(1 → 2)-Man, GlcA-(1 → 3)-GalN, and another disaccharide consisting of a hexuronic acid linked to a hexose were found in the hydrolysates, which indicated the existence of AGSP (abalone gonad sulfated polysaccharide) with the backbone composed of → 2)-α-Man(1 → 4)-β-GlcA(1 → repeating unit, AAP (abalone glycosaminoglycan-like polysaccharide) with the backbone of → 3)-GalNAc-(1 → 2)-GlcA-(1 → 3)-GalNAc-(1 → 4)-GlcA-(1 → repeating unit, and unidentified DS1P containing a hexuronic acid linked to a hexose unit, respectively. As shown by extracted ion chromatograms (XICs), AAP was the only UACP found in pleopods of the two gastropods; gonads and viscera of Haliotis contained DS1P and AGSP, while those of Volutharpa contained DS1P, AGSP as well as AAP. Monosaccharides in the acid hydrolysates were demonstrated in XICs by extracting their corresponding PMP derivative quasi-molecular ions one by one, and the results indicated the similar conclusion to the disaccharide analysis. Therefore, it could be concluded that polysaccharides from pleopods of the two gastropods are very similar, while those from their viscera and gonads differ greatly. Copyright © 2015 Elsevier Ltd. All rights reserved.

Literatuuronderzoek HPLC-methoden voor vitamine E

OpenAIRE

Altena, A.; Hollman, P.C.H.

1985-01-01

Doel van dit onderzoek is: het inventariseren van HPLC-methoden voor vitamine E, eventueel in combinatie met vitamine A, in levensmiddelen. Een overzicht van de in de literatuur beschreven HPLC-methoden vanaf ca. 1977 wordt gegeven.

Precise and accurate isotope ratio measurements by ICP-MS.

Science.gov (United States)

Becker, J S; Dietze, H J

2000-09-01

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

Sensitivity of GC-EI/MS, GC-EI/MS/MS, LC-ESI/MS/MS, LC-Ag(+) CIS/MS/MS, and GC-ESI/MS/MS for analysis of anabolic steroids in doping control.

Science.gov (United States)

Cha, Eunju; Kim, Sohee; Kim, Ho Jun; Lee, Kang Mi; Kim, Ki Hun; Kwon, Oh-Seung; Lee, Jaeick

2015-01-01

This study compared the sensitivity of various separation and ionization methods, including gas chromatography with an electron ionization source (GC-EI), liquid chromatography with an electrospray ionization source (LC-ESI), and liquid chromatography with a silver ion coordination ion spray source (LC-Ag(+) CIS), coupled to a mass spectrometer (MS) for steroid analysis. Chromatographic conditions, mass spectrometric transitions, and ion source parameters were optimized. The majority of steroids in GC-EI/MS/MS and LC-Ag(+) CIS/MS/MS analysis showed higher sensitivities than those obtained with other analytical methods. The limits of detection (LODs) of 65 steroids by GC-EI/MS/MS, 68 steroids by LC-Ag(+) CIS/MS/MS, 56 steroids by GC-EI/MS, 54 steroids by LC-ESI/MS/MS, and 27 steroids by GC-ESI/MS/MS were below cut-off value of 2.0 ng/mL. LODs of steroids that formed protonated ions in LC-ESI/MS/MS analysis were all lower than the cut-off value. Several steroids such as unconjugated C3-hydroxyl with C17-hydroxyl structure showed higher sensitivities in GC-EI/MS/MS analysis relative to those obtained using the LC-based methods. The steroids containing 4, 9, 11-triene structures showed relatively poor sensitivities in GC-EI/MS and GC-ESI/MS/MS analysis. The results of this study provide information that may be useful for selecting suitable analytical methods for confirmatory analysis of steroids. Copyright © 2015 John Wiley & Sons, Ltd.

Immunosuppressant therapeutic drug monitoring by LC-MS/MS: workflow optimization through automated processing of whole blood samples.

Science.gov (United States)

Marinova, Mariela; Artusi, Carlo; Brugnolo, Laura; Antonelli, Giorgia; Zaninotto, Martina; Plebani, Mario

2013-11-01

Although, due to its high specificity and sensitivity, LC-MS/MS is an efficient technique for the routine determination of immunosuppressants in whole blood, it involves time-consuming manual sample preparation. The aim of the present study was therefore to develop an automated sample-preparation protocol for the quantification of sirolimus, everolimus and tacrolimus by LC-MS/MS using a liquid handling platform. Six-level commercially available blood calibrators were used for assay development, while four quality control materials and three blood samples from patients under immunosuppressant treatment were employed for the evaluation of imprecision. Barcode reading, sample re-suspension, transfer of whole blood samples into 96-well plates, addition of internal standard solution, mixing, and protein precipitation were performed with a liquid handling platform. After plate filtration, the deproteinised supernatants were submitted for SPE on-line. The only manual steps in the entire process were de-capping of the tubes, and transfer of the well plates to the HPLC autosampler. Calibration curves were linear throughout the selected ranges. The imprecision and accuracy data for all analytes were highly satisfactory. The agreement between the results obtained with manual and those obtained with automated sample preparation was optimal (n=390, r=0.96). In daily routine (100 patient samples) the typical overall total turnaround time was less than 6h. Our findings indicate that the proposed analytical system is suitable for routine analysis, since it is straightforward and precise. Furthermore, it incurs less manual workload and less risk of error in the quantification of whole blood immunosuppressant concentrations than conventional methods. © 2013.

Re-purification of labelled ferritin antigen with HPLC

International Nuclear Information System (INIS)

Zhang Haoyi; Jin Lichun

2002-01-01

Objective: To improve the quality of long-term stored labelled ferritin antigen with HPLC. Methods: The antigen was analyzed and purified with HPLC and again analyzed with RIA afterwards. Results: Ferritin antigen underwent significant polymerization after long-term (aggregation) storage. After re-purification with HPLC, its immuno-activity and labelled specific radioactivity were both significantly improved. Conclusion: Quality of stored ferritin RIA kit could be greatly improved after re-purification with HPLC

Selenium speciation and isotope composition in 77Se-enriched yeast using gradient elution HPLC separation and ICP-dynamic reaction cell-MS

DEFF Research Database (Denmark)

Larsen, Erik Huusfeldt; Sloth, Jens Jørgen; Hansen, M.

2003-01-01

using the enriched Se-77-selenite as substrate, were released by enzymatic hydrolysis using (I), a beta-glucosidase followed by a protease mixture, and (II), a commercial protease preparation. For selenium speciation the chromatographic selectivity of the cation exchange HPLC system was adjusted...

DIRECT INFUSION ESI-MS APPLIED IN THE DETECTION OF BYPRODUCTS DUE TO REDUCTIVE DEGRADATION OF ACETAMIPRID BY ZERO-VALENT IRON

Directory of Open Access Journals (Sweden)

Jean C. Cruz

2015-09-01

Full Text Available This study investigated the reductive degradation of acetamiprid (5 mg L-1 in aqueous medium (at pH 2.0 induced by zero-valent iron (50 mg. The process was monitored using high-performance liquid chromatography (HPLC to determine the degradation rate as a function of reaction time, and direct infusion electrospray ionization mass spectrometry (DI-ESI-MS to search for (and potentially characterize any possible byproducts formed during degradation. The results obtained via HPLC showed that after 60 min, the degradation of the substrate reached nearly 100% in an acidic medium, whereas the mineralization rate (as determined by total organic carbon measurements was as low as 3%. Data obtained by DI-ESI-MS showed that byproducts were formed mainly by insertions of hydrogen atoms into the nitrile, imine, and pyridine ring moieties, in addition to the observation of chlorine substitution by hydrogen replacement (hydrodechlorination reactions.

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

Science.gov (United States)

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

2015-01-01

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

HPLC for quality control of polyimides

Science.gov (United States)

Young, P. R.; Sykes, G. F.

1979-01-01

High Pressure Liquid Chromatography (HPLC) as a quality control tool for polyimide resins and prepregs are presented. A data base to help establish accept/reject criteria for these materials was developed. This work is intended to supplement, not replace, standard quality control tests normally conducted on incoming resins and prepregs. To help achieve these objectives, the HPLC separation of LARC-160 polyimide precursor resin was characterized. Room temperature resin aging effects were studied. Graphite reinforced composites made from fresh and aged resin were fabricated and tested to determine if changes observed by HPLC were significant.

Simultaneous Release and Labeling of O- and N-Glycans Allowing for Rapid Glycomic Analysis by Online LC-UV-ESI-MS/MS.

Science.gov (United States)

Wang, Chengjian; Lu, Yu; Han, Jianli; Jin, Wanjun; Li, Lingmei; Zhang, Ying; Song, Xuezheng; Huang, Linjuan; Wang, Zhongfu

2018-05-24

Most glycoproteins and biological protein samples undergo both O- and N-glycosylation, making characterization of their structures very complicated and time-consuming. Nevertheless, to fully understand the biological functions of glycosylation, both the glycosylation forms need to be analyzed. Herein we report a versatile, convenient one-pot method in which O- and N-glycans are simultaneously released from glycoproteins and chromogenically labeled in situ and thus available for further characterization. In this procedure, glycoproteins are incubated with 1-phenyl-3-methyl-5-pyrazolone (PMP) in aqueous ammonium hydroxide, making O-glycans released from protein backbones by β-elimination and N-glycans liberated by alkaline hydrolysis. The released glycans are promptly derivatized with PMP in situ by Knoevenagel condensation and Michael addition, with peeling degradation almost completely prevented. The recovered mixture of O- and N-glycans as bis-PMP derivatives features strong ultraviolet (UV) absorbing ability and hydrophobicity, allowing for high-resolution chromatographic separation and high-sensitivity spectrometric detection. Using this technique, O- and N-glycans were simultaneously prepared from some model glycoproteins and complex biological samples, without significant peeling, desialylation, deacetylation, desulfation or other side-reactions, and then comprehensively analyzed by online HILIC-UV-ESI-MS/MS and RP-HPLC-UV-ESI-MS/MS, with which some novel O- and N-glycan structures were first found. This method provides a simple, versatile strategy for high-throughput glycomics analysis.

Analysis of plasma protein adsorption onto DC-Chol-DOPE cationic liposomes by HPLC-CHIP coupled to a Q-TOF mass spectrometer

KAUST Repository

Capriotti, Anna Laura; Caracciolo, Giulio; Caruso, Giuseppe; Cavaliere, Chiara; Pozzi, Daniela; Samperi, Roberto; Laganà , Aldo

2010-01-01

Plasma protein adsorption is regarded as a key factor in the in vivo organ distribution of intravenously administered drug carriers, and strongly depends on vector surface characteristics. The present study aimed to characterize the "protein corona" absorbed onto DC-Chol-DOPE cationic liposomes. This system was chosen because it is one of the most efficient and widely used non-viral formulations in vitro and a potential candidate for in vivo transfection of genetic material. After incubation of human plasma with cationic liposomes, nanoparticle-protein complex was separated from plasma by centrifugation. An integrated approach based on protein separation by one-dimensional 12% polyacrylamide gel electrophoresis followed by the automated HPLC-Chip technology coupled to a high-resolution mass spectrometer was employed for protein corona characterization. Thirty gel lanes, approximately 2 mm, were cut, digested and analyzed by HPLC-MS/MS. Fifty-eight human plasma proteins adsorbed onto DC-Chol-DOPE cationic liposomes were identified. The knowledge of the interactions of proteins with liposomes can be exploited for future controlled design of colloidal drug carriers and possibly in the controlled creation of biocompatible surfaces of other devices that come into contact with proteins in body fluids. © 2010 Springer-Verlag.

Analysis of plasma protein adsorption onto DC-Chol-DOPE cationic liposomes by HPLC-CHIP coupled to a Q-TOF mass spectrometer

KAUST Repository

Capriotti, Anna Laura

2010-09-22

Plasma protein adsorption is regarded as a key factor in the in vivo organ distribution of intravenously administered drug carriers, and strongly depends on vector surface characteristics. The present study aimed to characterize the "protein corona" absorbed onto DC-Chol-DOPE cationic liposomes. This system was chosen because it is one of the most efficient and widely used non-viral formulations in vitro and a potential candidate for in vivo transfection of genetic material. After incubation of human plasma with cationic liposomes, nanoparticle-protein complex was separated from plasma by centrifugation. An integrated approach based on protein separation by one-dimensional 12% polyacrylamide gel electrophoresis followed by the automated HPLC-Chip technology coupled to a high-resolution mass spectrometer was employed for protein corona characterization. Thirty gel lanes, approximately 2 mm, were cut, digested and analyzed by HPLC-MS/MS. Fifty-eight human plasma proteins adsorbed onto DC-Chol-DOPE cationic liposomes were identified. The knowledge of the interactions of proteins with liposomes can be exploited for future controlled design of colloidal drug carriers and possibly in the controlled creation of biocompatible surfaces of other devices that come into contact with proteins in body fluids. © 2010 Springer-Verlag.

Discrimination and classification of tobacco wastes by identification and quantification of polyphenols with LC–MS/MS

Directory of Open Access Journals (Sweden)

JUN WANG

2010-07-01

Full Text Available The chemical composition of polyphenols in tobacco waste was identified by HPLC-PDA–ESI/MS/MS and the contents of chlorogenic acids and rutin in 10 varieties of tobacco wastes were determined by HPLC–UV. The relationships between the contents of active polyphenols and the varieties of tobacco wastes were interpreted by hierarchical cluster analysis (HCA and principal component analysis (PCA. The results showed that 15 polyphenols were identified in a methanolic extract of dried tobacco waste. The tobacco wastes were characterized by high levels of chlorogenic acids (3-CQA, 5-CQA, and 4-CQA and rutin; their ranges in the 10 tobacco varieties were 0.116–0.196, 0.686–1.781, 0.094–0.192, and 0.413–0.998 %, respectively. According to multivariate statistics models, two active compound variables can be considered important for the discrimination of the varieties of tobacco wastes: chlorogenic acids and rutin. Consequently, samples of 10 tobacco varieties were characterized into three groups by HCA based on the PCA pattern. In conclusion, tobacco waste could be used as a new pharmaceutical material for the production of natural chlorogenic acids and rutin in the ethnopharmacological industry.

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

NARCIS (Netherlands)

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

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

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

Science.gov (United States)

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

2007-11-28

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

Extraction and identification of flavonoids from parsley extracts by HPLC analysis

Science.gov (United States)

Stan, M.; Soran, M. L.; Varodi, C.; Lung, I.

2012-02-01

Flavonoids are phenolic compounds isolated from a wide variety of plants, and are valuable for their multiple properties, including antioxidant and antimicrobial activities. In the present work, parsley (Petroselinum crispum L.) extracts were obtained by three different extraction techniques: maceration, ultrasonic-assisted and microwave-assisted solvent extractions. The extractions were performed with ethanol-water mixtures in various ratios. From these extracts, flavonoids like the flavones apigenin and luteolin, and the flavonols quercetin and kaempferol were identified using an HPLC Shimadzu apparatus equipped with PDA and MS detectors. The separation method involved a gradient step. The mobile phase consisted of two solvents: acetonitrile and distilled water with 0.1% formic acid. The separation was performed on a RP-C18 column.

Quantitative determination of trigonelline in mouse serum by means of hydrophilic interaction liquid chromatography-MS/MS analysis: Application to a pharmacokinetic study.

Science.gov (United States)

Szczesny, Damian; Bartosińska, Ewa; Jacyna, Julia; Patejko, Małgorzata; Siluk, Danuta; Kaliszan, Roman

2018-02-01

Trigonelline is a pyridine alkaloid found in fenugreek seeds and coffee beans. Most of the previous studies are concerned with the quantification of trigonelline along with other constituents in coffee herbs or beverages. Only a few have focused on its determination in animal or human tissues by applying different modes of HPLC with UV or MS detection. The aim of the study was to develop and validate a fast and simple method for trigonelline determination in serum by the use of hydrophilic interaction liquid chromatography (HILIC) with ESI-MS/MS detection. Separation of trigonelline was achieved on a Kinetex HILIC column operated at 35°C with acetonitrile-ammonium formate (10 mm, pH = 3) buffer mixture (55:45, v/v) as the mobile phase. The developed method was successfully applied to determine trigonelline concentration in mouse serum after intravenous administration of 10 mg/kg. The developed assay is sensitive (limit of detection = 1.5 ng/mL, limit of quantification = 5.0 ng/mL) and linear in a concentration range from 5.0 to 250.0 ng/mL. Sample preparation is limited to deproteinization, centrifugation and filtration. The application of the HILIC mode of chromatography with MS detection and selection of deuterated trigonelline as internal standard allowed a rapid and precise method of trigonelline quantification to be to developed. Copyright © 2017 John Wiley & Sons, Ltd.

Development and validation of an LC-MS/MS method for the determination of biogenic amines in wines and beers.

Science.gov (United States)

Nalazek-Rudnicka, Katarzyna; Wasik, Andrzej

2017-01-01

Biogenic amines are group of organic, basic, nitrogenous compounds that naturally occur in plant, microorganism, and animal organisms. Biogenic amines are mainly produced through decarboxylation of amino acids. They are formed during manufacturing of some kind of food and beverages such as cheese, wine, or beer. Histamine, cadaverine, agmatine, tyramine, putrescine, and β -phenylethylamine are the most common biogenic amines found in wines and beers. This group of compounds can be toxic at high concentrations; therefore, their control is very important. Analysis of biogenic amines in alcoholic drinks (beers and wines) was carried out by HPLC-MS/MS after their derivatization with p -toluenesulfonyl chloride (tosyl chloride). The developed method has been applied for analysis of seventeen biogenic amines in twenty-eight samples of lager beers and in twelve samples of different homemade wines (white grape, red grape, strawberry, chokeberry, black currant, plum, apple, raspberry, and quince). The developed method is sensitive and repeatable for majority of the analytes. It is versatile and can be used for the determination of biogenic amines in various alcoholic beverages.

HPLC ‘Multi-Analyte’ Detection Method

Energy Technology Data Exchange (ETDEWEB)

Dudar, E. [Plant Protection & Soil Conservation Service of Budapest, Budapest (Hungary)

2009-07-15

The application of multi-analyte methods for pesticides carrying chromophoric structures by HPLC is described. Details are given on the materials and methods used. Recorded UV spectra of active substances are presented for allowing the verification of purity and the confirmation of substances eluting from the HPLC column. (author)

An Efficient Method for the Preparative Isolation and Purification of Flavonoids from Leaves of Crataegus pinnatifida by HSCCC and Pre-HPLC.

Science.gov (United States)

Wen, Lei; Lin, Yunliang; Lv, Ruimin; Yan, Huijiao; Yu, Jinqian; Zhao, Hengqiang; Wang, Xiao; Wang, Daijie

2017-05-09

In this work, flavonoid fraction from the leaves of Crataegus pinnatifida was separated into its seven main constituents using a combination of HSCCC coupled with pre-HPLC. In the first step, the total flavonoid extract was subjected to HSCCC with a two-solvent system of chloroform/methanol/water/ n -butanol (4:3:2:1.5, v/v ), yielding four pure compounds, namely (-)-epicatechin ( 1 ), quercetin-3- O -(2,6-di-α-l-rhamnopyranosyl)-β-d-galactopyranoside ( 2 ), 4''- O -glucosylvitexin ( 3 ) and 2''- O -rhamnosylvitexin ( 4 ) as well as a mixture of three further flavonoids. An extrusion mode was used to rapidly separate quercetin-3- O -(2,6-di-α-l-rhamnopyranosyl)-β-d-galactopyranoside with a big K D -value. In the second step, the mixture that resulted from HSCCC was separated by pre-HPLC, resulting in three pure compounds including: vitexin ( 5 ), hyperoside ( 6 ) and isoquercitrin ( 7 ). The purities of the isolated compounds were established to be over 98%, as determined by HPLC. The structures of these seven flavonoids were elucidated by ESI-MS and NMR spectroscopic analyses.

The 4-pyridylmethyl ester as a protecting group for glutamic and aspartic acids: 'flipping' peptide charge states for characterization by positive ion mode ESI-MS.

Science.gov (United States)

Garapati, Sriramya; Burns, Colin S

2014-03-01

Use of the 4-pyridylmethyl ester group for side-chain protection of glutamic acid residues in solid-phase peptide synthesis enables switching of the charge state of a peptide from negative to positive, thus making detection by positive ion mode ESI-MS possible. The pyridylmethyl ester moiety is readily removed from peptides in high yield by hydrogenation. Combining the 4-pyridylmethyl ester protecting group with benzyl ester protection reduces the number of the former needed to produce a net positive charge and allows for purification by RP HPLC. This protecting group is useful in the synthesis of highly acidic peptide sequences, which are often beset by problems with purification by standard RP HPLC and characterization by ESI-MS. Copyright © 2014 European Peptide Society and John Wiley & Sons, Ltd.

Quantification of hydroxyurea in human plasma by HPLC-MS/MS and its application to pharmacokinetics in patients with chronic myeloid leukaemia.

Science.gov (United States)

Hai, Xin; Guo, Meihua; Gao, Chunlu; Zhou, Jin

2017-04-15

Hydroxyurea (HU) has been used in the treatment of chronic myeloid leukaemia (CML) and other myeloproliferative malignancies. Considering patient's wide variation in clinical response to HU, a new and simple liquid chromatography-tandem mass spectrometry (LC-MS/MS) method was developed and validated to monitor patients' compliance to treatment and investigate the pharmacokinetics of HU in patients with CML. Stable isotope labeled HU- 13 C 1 , 15 N 2 was used as internal standard. Plasma samples were treated with acetonitrile to precipitate protein. The supernatant was injected directly without derivatization and separated on a hydrophilic interaction liquid chromatography column. HU was quantitatively analyzed with a mobile phase of acetonitrile-1.5mM ammonium formate (90:10, V:V) within 3min. The proposed method provided a linearity range of 1-200μg/mL. The coefficients of variation for intra- and inter-day precision were less than 2.07% and 4.28%, respectively, while the accuracy (bias) was in the range of -3.77 to 2.96%. This method was satisfactorily applied to the determination of HU in two patients with CML. It is suitable for supporting pharmacokinetic studies and clinical therapeutic monitoring. Copyright © 2017 Elsevier B.V. All rights reserved.

New insight into the unresolved HPLC broad peak of Cabernet Sauvignon grape seed polymeric tannins by combining CPC and Q-ToF approaches.

Science.gov (United States)

Ma, Wen; Waffo-Téguo, Pierre; Alessandra Paissoni, Maria; Jourdes, Michäel; Teissedre, Pierre-Louis

2018-05-30

Polymeric tannins from grapes have always been reported as an unresolved broad peak in HPLC chromatograms, and this has severely limited their identification to date. This study aimed to disassemble this broad peak and explore the polymeric tannin molecules inside. By applying centrifugal partition chromatography (CPC), an efficient separation approach was developed to split the broad peak of grape seed tannins into fractions. Then, the fractions were analyzed by Q-ToF (quadrupole time-of-flight mass spectrometry) to determine the corresponding structures of the tannins. The results suggest that grape seed polymeric tannins were eluted consecutively according to their degree of polymerization (DP). Condensed tannins identified in wine grape seed have a range of DP and degree of galloylation (DG) up to 20 and 11, respectively. The molecular mass of the largest molecule detected was 6067. To our knowledge, this is the first report to offer an insight into the broad peak of polymeric tannins found with HPLC and to characterize the tannins with a DP up to 20 as shown by HRMS and MS/MS data. Copyright © 2018 Elsevier Ltd. All rights reserved.

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

Science.gov (United States)

Stanislawska, Magdalena; Janasik, Beata; Wasowicz, Wojciech

2013-12-15

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

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

OpenAIRE

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

2008-01-01

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

Expermental Studies of quantitative evaluation using HPLC

Directory of Open Access Journals (Sweden)

Ki Rok Kwon

2005-06-01

Full Text Available Methods : This study was conducted to carry out quantitative evaluation using HPLC Content analysis was done using HPLC Results : According to HPLC analysis, each BVA-1 contained approximately 0.36㎍ melittin, and BVA-2 contained approximately 0.54㎍ melittin. But the volume of coating was so minute, slight difference exists between each needle. Conclusion : Above results indicate that the bee venom acupuncture can complement shortcomings of syringe usage as a part of Oriental medicine treatment, but extensive researches should be done for further verification.

Evaluation of a new preparative supercritical fluid chromatography system for compound library purification: the TharSFC SFC-MS Prep-100 system.

Science.gov (United States)

Ebinger, Katalin; Weller, Harold N; Kiplinger, Jeffrey; Lefebvre, Paul

2011-06-01

Preparative HPLC-MS is often the method of choice for purification of small amounts (libraries for drug discovery. The method is robust, well proven, and widely applicable. In contrast, preparative supercritical fluid chromatography coupled with mass spectrometry (SFC-MS) has seen only slow acceptance for the same application--despite some potential scientific and economic advantages. One of the reasons for slow adoption of SFC-MS is the lack of well-proven, robust, and commercially available instrumentation. In early 2009, TharSFC (a Waters Company, Pittsburgh, PA) introduced a new fully integrated system for preparative SFC-MS: The SFC-MS Prep-100. We report herein an objective evaluation of the SFC-MS Prep-100, including tests for pump and autosampler performance, sample recovery, sample carryover, fraction triggering, detector/fraction collector synchronization, and overall robustness. Our results suggest that the SFC-MS Prep-100 represents a significant advance over previous generation instrumentation. Copyright © 2011 Society for Laboratory Automation and Screening. Published by Elsevier Inc. All rights reserved.

Capillary-HPLC with tandem mass spectrometry in analysis of alkaloid dyestuffs - a new approach.

Science.gov (United States)

Dąbrowski, Damian; Lech, Katarzyna; Jarosz, Maciej

2018-05-01

Development of the identification method of alkaloid compounds in Amur cork tree as well as not examined so far Oregon grape and European Barberry shrubs are presented. The novel approach to separation of alkaloids was applied and the capillary-high-performance liquid chromatography (capillary-HPLC) system was used, which has never previously been reported for alkaloid-based dyestuffs analysis. Its optimization was conducted with three different stationary phases (unmodified octadecylsilane-bonded silica, octadecylsilane modified with polar groups and silica-bonded pentaflourophenyls) as well as with different solvent buffers. Detection of the isolated compounds was carried out using diode-array detector (DAD) and tandem mass spectrometer with electrospray ionization (ESI MS/MS). The working parameters of ESI were optimized, whereas the multiple reactions monitoring (MRM) parameters of MS/MS detection were chosen based on the product ion spectra of the quasi-molecular ions. Calibration curve of berberine has been estimated (y = 1712091x + 4785.03 with the correlation coefficient 0.9999). Limit of detection and limit of quantification were calculated to be 3.2 and 9.7 ng/mL, respectively. Numerous alkaloids (i.e., berberine, jatrorrhizine and magnoflorine, as well as phellodendrine, menisperine and berbamine) were identified in the extracts from alkaloid plants and silk and wool fibers dyed with these dyestuffs, among them their markers. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Sensitive measurement of positron emitters eluted from HPLC

International Nuclear Information System (INIS)

Takei, Makoto; Kida, Takayo; Suzuki, Kazutoshi

2001-01-01

For sensitive analysis of the radioactive-metabolite in human PET, a radio-HPLC system coupled to a newly designed positron detector was constructed. The detector had the advantages of low noise level (1.7±1.0 cpm) and high sensitivity (32±1%) due to coincidence counting and large BGO crystals. Furthermore, the detector was easy to move, since a pair of the BGO housings coupled to photomultipliers was effectively arranged in parallel and a HPLC cell with different volume could be inserted between the BGO housing. This radio-HPLC system was useful for analyzing samples with low radioactivity. It was applied to the measurement of [ 11 C]FLB457 in plasma, having high affinity and high selectivity with dopamine D2 receptors. Extremely low radioactivity of [ 11 C]FLB457 (2500 dpm) could be analyzed by using the radio-HPLC system. The performance of this detector was compared with those of commercially available systems that had been used as sensitive detectors for HPLC

Chemical profiling of anti-hepatocellular carcinoma constituents from Caragana tangutica Maxim. by off-line semi-preparative HPLC-NMR.

Science.gov (United States)

Yang, Xinzhou; Huang, Mi; Cai, Jinyan; Lv, Dan; Lv, Jingnan; Zheng, Sijian; Ma, Xinhua; Zhao, Ping; Wang, Qiang

2017-05-01

An EtOAc fraction from the roots of Caragana tangutica Maxim. (CTEA) displayed promising anti-hepatocellular carcinoma (HCC) activity during screening of a traditional Chinese ethnic herb library against HepG2 and Hep3B cell lines. HPLC-based activity profiling of CTEA by combination of MS-guided large-scale semi-preparative HPLC and NMR methods led to the identification of a new pterocarpan glycoside, (-)-maackiain 3-O-6'-O-methyl malonyl-β-d-glucopyranoside (1), together with three known pterocarpan glycosides, (-)-maackiain 3-O-β-d-glucopyranoside (2), 3-O-6'-O-acrylyl-β-d-galactopyranoside (3), and (-)-maackiain 3-O-6'-O-acetyl-β-d-glucopyranoside (4). Compound 1 was isolated during a drug discovery programme aimed at identifying new anti-HCC leads from a natural product library. Anti-HCC study showed that all four compounds exhibited cytotoxic activity with IC 50 values range of 29.1-53.5 μg/mL against HepG2 and Hep3B cell lines.

HPLC-ESR techniques for detection of complex trapped radicals

International Nuclear Information System (INIS)

Tu Tiecheng; Dong Jirong; Lin Nianyun; Xie Leidong; Liu Rengzhong

1992-01-01

High performance liquid chromatography (HPLC) and ESR combined examination of radical species is an advanced techniques for separation and identification of complex radical species. At SRCL, Waters 990 HPLC has been used to separate the complex trapped radicals and Varian E-112 ESR spectrometer to record the spectra of single trapped radicals after HPLC separation. The advantages of the combined techniques are described as bellow: HPLC is used to separate the long-lived complex trapped radicals derived from reaction of short-lived radicals with spin trap. ESR spectra from single trapped radicals, obtained following HPLC separation of complex trapped radicals, are recorded one by one and well resolved. The structures of short-lived radicals can be inferred from the ESR spectra of the long-lived trapped radicals

Spokojenost s celkovým pracovním životem jako indikátor kvality pracovního života: analýza výsledků šetření

Czech Academy of Sciences Publication Activity Database

Červenka, Jan

2015-01-01

Roč. 8, červen (2015) ISSN 1803-3687 R&D Projects: GA TA ČR(CZ) TD020046 Institutional support: RVO:68378025 Keywords : quality of working life * satisfaction with general working life * satisfaction with life Subject RIV: AO - Sociology, Demography http://www.bozpinfo.cz/win/josra/josra-kvalita-zivota/spokojenost-analyza-vysledku.html

Distributed-memory matrix computations

DEFF Research Database (Denmark)

Balle, Susanne Mølleskov

1995-01-01

The main goal of this project is to investigate, develop, and implement algorithms for numerical linear algebra on parallel computers in order to acquire expertise in methods for parallel computations. An important motivation for analyzaing and investigating the potential for parallelism in these......The main goal of this project is to investigate, develop, and implement algorithms for numerical linear algebra on parallel computers in order to acquire expertise in methods for parallel computations. An important motivation for analyzaing and investigating the potential for parallelism...... in these algorithms is that many scientific applications rely heavily on the performance of the involved dense linear algebra building blocks. Even though we consider the distributed-memory as well as the shared-memory programming paradigm, the major part of the thesis is dedicated to distributed-memory architectures....... We emphasize distributed-memory massively parallel computers - such as the Connection Machines model CM-200 and model CM-5/CM-5E - available to us at UNI-C and at Thinking Machines Corporation. The CM-200 was at the time this project started one of the few existing massively parallel computers...

Characterization of anthocyanins in the hybrid progenies derived from Iris dichotoma and I. domestica by HPLC-DAD-ESI/MS analysis.

Science.gov (United States)

Xu, Wenji; Luo, Gangjun; Yu, Fengyang; Jia, Qingxiang; Zheng, Yang; Bi, Xiaoying; Lei, Jiajun

2018-06-01

Iris dichotoma with different flower colors and I. domestica are beardless wild irises belonging to the family Iridaceae that bloom in the summer and have long flowering periods. In this study, we collected three accessions of I. dichotoma with violet, yellow, and white flowers, respectively, in China, and crossed them with I. domestica individuals. The flower color of the hybrids derived from these crosses was categorized into eight groups: violet, purple, brown, orange, red, pink, yellow, and white. From this population, 45 individuals were selected for analysis, and their fully expanded inner and outer perianths were harvested for extraction of anthocyanins. Using high-performance liquid chromatography-mass spectrometry (HPLC-MS) analysis, 29 anthocyanins were identified by comparing MS and UV-visible spectra and elution order based on published data and guidelines. The 29 anthocyanins were classified into six groups: non-acylated glycosides (3RG, 3RG5G), acetylglycosides (3acRG5G), p-coumaroylglycosides (3pCRG, 3pCRG5G), caffeoylglycosides (3CRG5G), feruloylglycosides (3feRG, 3feRG5G), and acetyl-(p-coumaroyl) glycosides (3ac-pCRG5G). Acylated anthocyanin contents were considerably higher than non-acylated anthocyanin contents in the individuals evaluated, regardless of flower color, except in the yellow-flowered I. dichotoma and its yellow-flowered progeny. We found ten anthocyanins derived from pelargonidin, including pelargonidin 3-O-(caffeoyl)rutinoside-5-O-glucoside (Pg3CRG5G), pelargonidin 3-O-(feruloyl)rutinoside-5-O-glucoside (Pg3feRG5G), and pelargonidin 3-O-(feruloyl)rutinoside (Pg3feRG), that have not yet been reported in other Iris species. Moreover, delphinidin 3-O-(feruloyl) rutinoside-5-O-glucoside (Dp3feRG5G), and delphinidin 3-O-(feruloyl)rutinoside (Dp3feRG) were also characterized for the first time in Iris. Two to five major anthocyanins were detected in the petals of the violet and purple groups, whereas those of the brown group

Methods and applications of HPLC-AMS

International Nuclear Information System (INIS)

Buchholz, Bruce A.; Dueker, Stephen R.; Lin, Yumei; Clifford, Andrew J.; Vogel, John S.

2000-01-01

Pharmacokinetics of physiologic doses of nutrients, pesticides, and herbicides can easily be traced in humans using a 14 C-labeled compound. Basic kinetics can be monitored in blood or urine by measuring the elevation in the 14 C content above the control predose tissue and converting to equivalents of the parent compound. High performance liquid chromatography (HPLC) is an excellent method for the chemical separation of complex mixtures whose profiles afford estimation of biochemical pathways of metabolism. Compounds elute from the HPLC systems with characteristic retention times and can be collected in fractions that can then be graphitized for AMS measurement. Unknowns are tentatively identified by co-elution with known standards and chemical tests that reveal functional groupings. Metabolites are quantified with the 14 C signal. Thoroughly accounting for the carbon inventory in the LC solvents, ion-pairing agents, samples, and carriers adds some complexity to the analysis. In most cases the total carbon inventory is dominated by carrier. Baseline background and stability need to be carefully monitored. Limits of quantitation near 10 amol of 14 C per HPLC fraction are typically achieved. Baselines are maintained by limiting injected 14 C activity <0.17 Bq (4.5 pCi) on the HPLC column

RAPID AND AUTOMATED PROCESSING OF MALDI-FTICR/MS DATA FOR N-METABOLIC LABELING IN A SHOTGUN PROTEOMICS ANALYSIS.

Science.gov (United States)

Jing, Li; Amster, I Jonathan

2009-10-15

Offline high performance liquid chromatography combined with matrix assisted laser desorption and Fourier transform ion cyclotron resonance mass spectrometry (HPLC-MALDI-FTICR/MS) provides the means to rapidly analyze complex mixtures of peptides, such as those produced by proteolytic digestion of a proteome. This method is particularly useful for making quantitative measurements of changes in protein expression by using (15)N-metabolic labeling. Proteolytic digestion of combined labeled and unlabeled proteomes produces complex mixtures that with many mass overlaps when analyzed by HPLC-MALDI-FTICR/MS. A significant challenge to data analysis is the matching of pairs of peaks which represent an unlabeled peptide and its labeled counterpart. We have developed an algorithm and incorporated it into a compute program which significantly accelerates the interpretation of (15)N metabolic labeling data by automating the process of identifying unlabeled/labeled peak pairs. The algorithm takes advantage of the high resolution and mass accuracy of FTICR mass spectrometry. The algorithm is shown to be able to successfully identify the (15)N/(14)N peptide pairs and calculate peptide relative abundance ratios in highly complex mixtures from the proteolytic digest of a whole organism protein extract.

HPLC-UV ATMOSPHERIC-PRESSURE IONIZATION MASS-SPECTROMETRIC DETERMINATION OF THE DOPAMINE-D2 AGONIST N-0923 AND ITS MAJOR METABOLITES AFTER OXIDATIVE-METABOLISM BY RAT-LIVER, MONKEY LIVER, AND HUMAN LIVER-MICROSOMES

NARCIS (Netherlands)

SWART, PJ; BRONNER, GM; BRUINS, AP; ENSING, K; TEPPER, PG; DEZEEUW, RA

1993-01-01

An innovative custom-built atmospheric ionization source afforded an opportunity to perform on-line LC/MS analysis and to obtain identification of metabolites without need to rely on radioactive profiling. An HPLC with a UV detector coupled to a modified R 3010 triple quadrupole mass spectrometer

Serum Metabolomics Study Based on LC-MS and Antihypertensive Effect of Uncaria on Spontaneously Hypertensive Rats

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Ana Liu

2018-01-01

Full Text Available Our previous studies have shown that Uncaria has an important role in lowering blood pressure, but its intervention mechanism has not been clarified completely in the metabolic level. Therefore, in this study, a combination method of HPLC-TOF/MS-based metabolomics and multivariate statistical analyses was employed to explore the mechanism and evaluate the antihypertensive effect of Uncaria. Serum samples were analyzed and identified by HPLC-TOF/MS, while the acquired data was further processed by partial least squares discriminant analysis (PLS-DA and orthogonal partial least squares discriminant analysis (OPLS-DA to discover the perturbed metabolites. A clear cluster among the different groups was obtained, and 7 significantly changed potential biomarkers were screened out. These biomarkers were mainly associated with lipid metabolism (dihydroceramide, ceramide, PC, LysoPC, and TXA2 and vitamin and amino acids metabolism (nicotinamide riboside, 5-HTP. The result indicated that Uncaria could decrease the blood pressure effectively, partially by regulating the above biomarkers and metabolic pathways. Analyzing and verifying the specific biomarkers, further understanding of the therapeutic mechanism and antihypertensive effect of Uncaria was acquired. Metabolomics provided a new insight into estimate of the therapeutic effect and dissection of the potential mechanisms of traditional Chinese medicine (TCM in treating hypertension.

Screening of Chemical Dyes in Traditional Chinese Medicine by HPTLC-MS.

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He, Fengyan; He, Yi; Zheng, Xiaowei; Wang, Ruizhong; Lu, Jing; Dai, Zhong; Ma, Shuangcheng

2018-05-01

It has been uncovered that chemical dyes are illegally used in traditional Chinese medicines to brighten color and cover up inferiority, which threaten the safety of patients. In the present study, an HPTLC-MS method was developed for the effective screening of 11 chemical dyes (Sudan I, II, III, and IV; 808 Scarlet; Sudan Red 7B; malachite green; Basic Orange 2; auramine; Orange II; and erythrosine) in traditional Chinese medicine (TCM) raw materials and Chinese patent medicines. Firstly, unwashed HPTLC plates were chosen by comparing the background signals of the TLC plates used directly and prewashed with analytical grade and HPLC grade solvents. Twice developments were conducted to isolate chemical dyes of different polarity. Possible adulterants were preliminarily identified by comparing Rf values and in situ UV-Vis spectra with those of the references. Further confirmation was conducted by tandem MS analysis via an elution head-based TLC-MS interface. Sudan I and IV, 808 Scarlet, and Orange II were successfully detected in eight batches of TCM. The proposed method could be applied as a reliable technology for the screening of chemical dyes in TCM.

A high-throughput robotic sample preparation system and HPLC-MS/MS for measuring urinary anatabine, anabasine, nicotine and major nicotine metabolites.

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Wei, Binnian; Feng, June; Rehmani, Imran J; Miller, Sharyn; McGuffey, James E; Blount, Benjamin C; Wang, Lanqing

2014-09-25

Most sample preparation methods characteristically involve intensive and repetitive labor, which is inefficient when preparing large numbers of samples from population-scale studies. This study presents a robotic system designed to meet the sampling requirements for large population-scale studies. Using this robotic system, we developed and validated a method to simultaneously measure urinary anatabine, anabasine, nicotine and seven major nicotine metabolites: 4-Hydroxy-4-(3-pyridyl)butanoic acid, cotinine-N-oxide, nicotine-N-oxide, trans-3'-hydroxycotinine, norcotinine, cotinine and nornicotine. We analyzed robotically prepared samples using high-performance liquid chromatography (HPLC) coupled with triple quadrupole mass spectrometry in positive electrospray ionization mode using scheduled multiple reaction monitoring (sMRM) with a total runtime of 8.5 min. The optimized procedure was able to deliver linear analyte responses over a broad range of concentrations. Responses of urine-based calibrators delivered coefficients of determination (R(2)) of >0.995. Sample preparation recovery was generally higher than 80%. The robotic system was able to prepare four 96-well plate (384 urine samples) per day, and the overall method afforded an accuracy range of 92-115%, and an imprecision of labor-saving for sample preparation, making it efficient and practical for routine measurements in large population-scale studies such as the National Health and Nutrition Examination Survey (NHANES) and the Population Assessment of Tobacco and Health (PATH) study. Published by Elsevier B.V.

Simultaneous Analysis of Saccharides between Fresh and Processed Radix Rehmanniae by HPLC and UHPLC-LTQ-Orbitrap-MS with Multivariate Statistical Analysis

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Shujuan Xue

2018-02-01

Full Text Available Radix Rehmanniae (RR is a kind of herb which is widely used in the clinical and food processing industry. There are four forms of RR used in traditional Chinese medicine practice, which include fresh RR (FRR, raw RR (RRR, processed RR (PRR, and another processed RR (APRR, in which the APRR was processed by nine cycles of repeated steaming and drying. There are a large number of saccharides in RR. However, the differences in content were shown by different processing methods. In this study, an effective method using high-performance liquid chromatography (HPLC and high-performance liquid chromatography-mass spectrometry (LC-MS coupled with multivariate statistical analysis to rapidly distinguish different RR samples and validate the proposed chemical conversion mechanism. The datasets of the content of saccharides were subjected to principal component analysis (PCA and one-way analysis of variance. The results showed that there different changes occurred in the contents of saccharides corresponding to the different processing methods, in which the contents of monosaccharides—namely arabinose, glucose, mannose, and galactose—had an increasing trend or remained relatively stable. However, the contents of fructose and oligosaccharides, including manninotriose, melibiose, sucrose, and raffinose, first increased and then reduced, or gradually decreased, yet the content of stachyose gradually decreased. The MSn data indicated that manninotriose, melibiose, and some monosaccharides were produced by the hydrolysis of oligosaccharides. In addition, the fragmentation pathways of 1-phenyl-3-methyl-5-pyrazolone (PMP derivatization of monosaccharides were also found that its glycosidic bond was first broken and subsequently its inside ring broke, and the characteristic fragment ions were produced at m/z 511.22, 493.20, 373.16, and 175.08 in the PMP derivatization of monosaccharides. In conclusion, this study illustrates the change and chemical conversion

Quality Evaluation of the Traditional Medicine Majun Mupakhi ELA via Chromatographic Fingerprinting Coupled with UHPLC-DAD-Quadrupole-Orbitrap-MS and the Antioxidant Activity In Vitro.

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Reheman, Ayinuer; Aisa, Haji Akber; Ma, Qing Ling; Nijat, Dilaram; Abdulla, Rahima

2018-01-01

By merging a high-performance liquid chromatography diode array detector (HPLC-DAD) method with high-performance thin-layer chromatography (HPTLC), an assay was developed for chemical fingerprinting and quantitative analysis of traditional medicine Majun Mupakhi ELA (MME), and constituent compounds were identified using HPLC coupled with UHPLC-DAD-Quadrupole-Orbitrap-MS method. In addition, the antioxidant capacity of MME was assessed based on the ability of components to scavenge radicals using in vitro method. Using a HPLC-DAD method with HPTLC easily validated the chemical fingerprinting results and quantified three characteristic components, namely, gallic acid (1), daidzein (2), and icariin (3), in commercial MMEs. The three compounds presented excellent regression values ( R 2 = 0.9999) in the ranges of the test and the method recovery was in the range from 100.49% to 100.68%. The fingerprints had 27 common characteristic peaks, of which 13 were verified by rapid UHPLC-DAD-Q-Orbitrap-MS analysis. In vitro antioxidant assays rapidly assessed and contrasted antioxidant activity or the free radical scavenging activity of the main polyphenolic classes in MMEs, and the antioxidant capacity was mostly affected by the presence of gallic acid. Thus, this study establishes a powerful and meaningful approach for MME quality control and for assessing in vitro antioxidant activity.

Hyphenation of solid-phase extraction with liquid chromatography and nuclear magnetic resonance: application of HPLC-DAD-SPE-NMR to identification of constituents of Kanahia laniflora.

Science.gov (United States)

Clarkson, Cailean; Staerk, Dan; Hansen, Steen Honoré; Jaroszewski, Jerzy W

2005-06-01

The introduction of on-line solid-phase extraction (SPE) in HPLC-NMR has dramatically enhanced the sensitivity of this technique by concentration of the analytes in a small-volume NMR flow cell and by increasing the amount of the analyte by multiple peak trapping. In this study, the potential of HPLC-DAD-SPE-NMR hyphenation was demonstrated by structure determination of complex constituents of flower, leaf, root, and stem extracts of an African medicinal plant Kanahia laniflora. The technique was shown to allow acquisition of high-quality homo- and heteronuclear 2D NMR data following analytical-scale HPLC separation of extract constituents. Four flavonol glycosides [kaempferol 3-O-(6-O-alpha-l-rhamnopyranosyl)-beta-d-glucopyranoside; kaempferol 3-O-(2,6-di-O-alpha-l-rhamnopyranosyl)-beta-d-glucopyranoside; quercetin 3-O-(2,6-di-O-alpha-l-rhamnopyranosyl)-beta-d-glucopyranoside (rutin); and isorhamnetin, 3-O-(6-O-alpha-l-rhamnopyranosyl)-beta-d-glucopyranoside] and three 5alpha-cardenolides [coroglaucigenin 3-O-6-deoxy-beta-d-allopyranoside; coroglaucigenin 3-O-(4-O-beta-d-glucopyranosyl)-6-deoxy-beta-d-glucopyranoside; 3'-O-acetyl-3'-epiafroside] were identified, with complete assignments of 1H and 13C resonances based on HSQC and HMBC spectra whenever required. Confirmation of the structures was provided by HPLC-MS data. The HPLC-DAD-SPE-NMR technique therefore speeds up the dereplication of complex mixtures of natural origin significantly, by characterization of individual extract components prior to preparative isolation work.

Quality Control of Selected Pesticides with HPLC

Energy Technology Data Exchange (ETDEWEB)

Karasali, H. [Benaki Phytopathological Institute Laboratory of Physical and Chemical Analysis of Pesticides, Ekalis (Greece)

2009-07-15

Laboratory data obtained on two different HPLC separation columns and detection by UV and DAD under repeatability conditions are presented and discussed. The behaviour of pesticides on different HPLC columns under gradient and isocratic conditions is evaluated concerning the applicability of respective methodologies. Representative chromatograms of real formulations and “empty” formlants are given for illustration. (author)

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

Science.gov (United States)

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

2016-07-01

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

Ultra high performance liquid chromatography with ion-trap TOF-MS for the fast characterization of flavonoids in Citrus bergamia juice.

Science.gov (United States)

Sommella, Eduardo; Pepe, Giacomo; Pagano, Francesco; Tenore, Gian Carlo; Dugo, Paola; Manfra, Michele; Campiglia, Pietro

2013-10-01

We have developed a fast ultra HPLC with ion-trap TOF-MS method for the analysis of flavonoids in Citrus bergamia juice. With respect to the typical methods for the analysis of these matrices based on conventional HPLC techniques, a tenfold faster separation was attained. The use of a core-shell particle column ensured high resolution within the fast analysis time of only 5 min. Unambiguous determination of flavonoid identity was obtained by the employment of a hybrid ion-trap TOF mass spectrometer with high mass accuracy (average error 1.69 ppm). The system showed good retention time and peak area repeatability, with maximum RSD% values of 0.36 and 3.86, respectively, as well as good linearity (R(2) ≥ 0.99). Our results show that ultra HPLC can be a useful tool for ultra fast qualitative/quantitative analysis of flavonoid compounds in citrus fruit juices. © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Detection of nonsterol isoprenoids by HPLC-MS/MS

NARCIS (Netherlands)

Henneman, Linda; van Cruchten, Arno G.; Denis, Simone W.; Amolins, Michael W.; Placzek, Andrew T.; Gibbs, Richard A.; Kulik, Willem; Waterham, Hans R.

2008-01-01

Isoprenoids constitute an important class of biomolecules that participate in many different cellular processes. Most available detection methods allow the identification of only one or two specific nonsterol isoprenoid intermediates following radioactive or fluorescent labeling. We here report a

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

Science.gov (United States)

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

2003-02-01

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

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

International Nuclear Information System (INIS)

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

2003-01-01

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

HPLC-DAD-ELSD Combined Pharmacodynamics and Serum Medicinal Chemistry for Quality Assessment of Huangqi Granule.

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Huaguo Chen

Full Text Available To more scientifically and reasonably control the quality of Huangqi Granules, preliminary studies on the pharmacodynamics and serum pharmacochemistry of this medicine were performed. DPPH and MTT experiments showed that water extracts of Huangqi Granules had good antioxidant activity and increased immunity. Timed blood samples collected 5 min, 15 min, and 30 min after oral administration of a set amount of Huangqi Granules were collected and tested using UPLC-ESI-MS/MS. As a result, calycosin-7-O-β-D-glucoside, ononin, calycosin, astragaloside IV, and formononetin were found to exist in rat blood after dosing, indicating that the five chemical compounds might have pharmacological activity, and based on this result, they were designated biomarkers for quality control of Huangqi Granules. Consequently, a simple, rapid and efficient method was developed in the present study for the simultaneous determination of the five characteristic compounds in Huangqi Granules using HPLC-DAD-ELSD.The separation was performed using an Agilent Hypersil ODS column (4.6 × 250 mm, 5 μm at 30 ℃. The mobile phase was composed of water (solvent A and acetonitrile (solvent B with a flow rate of 1 mL/min. The drift tube temperature of the ELSD system was set to 85 ℃, and the nitrogen pressure was 3.5 bar.All five characteristic compounds had good linear behavior with r2 values greater than 0.9972. The recoveries varied from 96.31% to 101.22%. Subsequently, the developed method was applied to evaluate the quality of Huangqi Granules from different batches, and hierarchical clustering analysis (HCA was used to analyze the classification of the samples based on the values of the five compounds.The established HPLC method combined with HCA proved to be effective to evaluate the quality of Huangqi Granules.

[Studies on HPLC-FPS of the saponins from Semen Ziziphi Spinosae].

Science.gov (United States)

Wu, He-zhen; Chen, Jing; Liu, Yan-wen

2006-09-01

To establish a method of HPLC-fingerprint spectrum (HPLC-FPS) for the active part in Semen Ziziphi Spinosae (SZS) in order to control the quality of SZS from different places. The gradient elution mode was applied in chromatographic separation, and data were analysed by" Similarity Evaluation software" to compare the HPLC-FPS of SZS from different places. The conditions for HPLC analysis of SZS were established and the FPS of samples from different habitats showed some differences. All components in the spectrum were separated well and the HPLC fingerprint method is repeatable. The method can be used in quality assessment of SZS.

LC-MS-MS Measurements of Urinary Creatinine and the Application of Creatinine Normalization Technique on Cotinine in Smokers’ 24 Hour Urine

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Hongwei Hou

2012-01-01

Full Text Available A simple and sensitive high performance liquid chromatography-tandem mass spectrometry (HPLC-ESI-MS-MS method was developed and validated for the quantification of creatinine in human urine. The analysis was carried out on an Agilent Zorbax Eclipse XDB-C18 column (2.1×150 mm, 3.5 μm. The mobile phase was 0.1% formic acid in water and 0.1% formic acid in acetonitrile (50/50, v/v. Linear calibration curves were obtained in the concentration range of 1–2000.0 ng/mL, with a lower limit of quantification of 0.99 ng/mL. The intra- and interday precision (RSD values were below 3%. The method was successfully applied to a bioequivalence study of creatinine in Chinese smokers and nonsmokers. The total cotinine in 24 h urine and cotinine : creatinine ratio were also positively associated (Pearson R=0.942, P<0.0001. However, cotinine : creatinine ratio varied significantly across smoking groups for the difference of individual. 24 h urinary cotinine was more appropriate for expressing correlation with tar than cotinine : creatinine ratio.

A novel UPLC-MS/MS method for sensitive quantitation of boldine in plasma, a potential anti-inflammatory agent: application to a pharmacokinetic study in rats.

Science.gov (United States)

Zeng, Rong-Jie; Li, Yu; Chen, Jian-Zhong; Chou, Gui-Xin; Gao, Yu; Shao, Jing-Wei; Jia, Lee; Wu, Sheng-Dong; Wu, Shui-Sheng

2015-03-01

Boldine is a potential anti-inflammatory agent found in several different plants. Published bioanalytical methods using HPLC with ultraviolet and fluorescent detection lacked enough sensitivity and required tedious sample preparation procedures. Herein, we describe the development of a novel ultra-high performance LC with MS/MS for determination of boldine in plasma. Boldine in plasma was recovered by liquid-liquid extraction using 1 mL of methyl tert-butyl ether. Chromatographic separation was performed on a C18 column at 45°C, with a gradient elution consisting of acetonitrile and water containing 0.1% (v/v) formic acid at a flow rate of 0.3 mL/min. The detection was performed on an electrospray triple-quadrupole MS/MS by positive ion multiple reaction monitoring mode. Good linearity (r(2) > 0.9926) was achieved in a concentration range of 2.555-2555 ng/mL with a lower limit of quantification of 2.555 ng/mL for boldine. The intra- and inter-day precisions of the assay were 1.2-6.0 and 1.8-7.4% relative standard deviation with an accuracy of -6.0-8.0% relative error. This newly developed method was successfully applied to a single low-dose pharmacokinetic study in rats and was demonstrated to be simpler and more sensitive than the published methods, allowing boldine quantification in reduced plasma volume. Copyright © 2014 John Wiley & Sons, Ltd.

Quantitative analysis of unconjugated and total bisphenol A in human urine using solid-phase extraction and UPLC-MS/MS: method implementation, method qualification and troubleshooting.

Science.gov (United States)

Buscher, Brigitte; van de Lagemaat, Dick; Gries, Wolfgang; Beyer, Dieter; Markham, Dan A; Budinsky, Robert A; Dimond, Stephen S; Nath, Rajesh V; Snyder, Stephanie A; Hentges, Steven G

2015-11-15

The aim of the presented investigation was to document challenges encountered during implementation and qualification of a method for bisphenol A (BPA) analysis and to develop and discuss precautions taken to avoid and to monitor contamination with BPA during sample handling and analysis. Previously developed and published HPLC-MS/MS methods for the determination of unconjugated BPA (Markham et al. Journal of Analytical Toxicology, 34 (2010) 293-303) [17] and total BPA (Markham et al. Journal of Analytical Toxicology, 38 (2014) 194-203) [20] in human urine were combined and transferred into another laboratory. The initial method for unconjugated BPA was developed and evaluated in two independent laboratories simultaneously. The second method for total BPA was developed and evaluated in one of these laboratories to conserve resources. Accurate analysis of BPA at sub-ppb levels is a challenging task as BPA is a widely used material and is ubiquitous in the environment at trace concentrations. Propensity for contamination of biological samples with BPA is reported in the literature during sample collection, storage, and/or analysis. Contamination by trace levels of BPA is so pervasive that even with extraordinary care, it is difficult to completely exclude the introduction of BPA into biological samples and, consequently, contamination might have an impact on BPA biomonitoring data. The applied UPLC-MS/MS method was calibrated from 0.05 to 25ng/ml. The limit of quantification was 0.1ng/ml for unconjugated BPA and 0.2ng/ml for total BPA, respectively, in human urine. Finally, the method was applied to urine samples derived from 20 volunteers. Overall, BPA can be analyzed in human urine with acceptable recovery and repeatability if sufficient measures are taken to avoid contamination throughout the procedure from sample collection until UPLC-MS/MS analysis. Copyright © 2015 The Authors. Published by Elsevier B.V. All rights reserved.

HPLC MS/MS method for quantification of meprobamate in human plasma: application to 24/7 clinical toxicology.

Science.gov (United States)

Delavenne, Xavier; Gay-Montchamp, Jean Pierre; Basset, Thierry

2011-01-15

We described the development and full validation of rapid and accurate liquid chromatography method, coupled with tandem mass spectrometry detection, for quantification of meprobamate in human plasma with [(13)C-(2)H(3)]-meprobamate as internal standard. Plasma pretreatment involved a one-step protein precipitation with acetonitrile. Separation was performed by reversed-phase chromatography on a Luna MercuryMS C18 (20 mm×4 mm×3 μm) column using a gradient elution mode. The mobile phase was a mix of distilled water containing 0.1% formic acid and acetonitrile containing 0.1% formic acid. The selected reaction monitoring transitions, in electrospray positive ionization, used for quantification were 219.2→158.2 m/z and 223.1→161.1m/z for meprobamate and internal standard, respectively. Qualification transitions were 219.2→97.0 and 223.1→101.1 m/z for meprobamate and internal standard, respectively. The method was linear over the concentration range of 1-300 mg/L. The intra- and inter-day precision values were below 6.4% and accuracy was within 95.3% and 103.6% for all QC levels (5, 75 and 200 mg/L). The lower limit of quantification was 1 mg/L. Total analysis time was reduced to 6 min including sample preparation. The present method is successfully applied to 24/7 clinical toxicology and demonstrated its usefulness to detect meprobamate poisoning. Copyright © 2010 Elsevier B.V. All rights reserved.

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

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Ćirić Biljana

2010-01-01

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

Comprehensive speciation of low-molecular weight selenium metabolites in mustard seeds using HPLC-electrospray linear trap/Orbitrap tandem mass spectrometry.

Science.gov (United States)

Ouerdane, Laurent; Aureli, Federica; Flis, Paulina; Bierla, Katarzyna; Preud'homme, Hugues; Cubadda, Francesco; Szpunar, Joanna

2013-09-01

An analytical methodology based on high-resolution high mass accuracy electrospray ionization (ESI) tandem MS assisted by Se-specific detection using inductively coupled plasma mass spectrometry (ICP MS) was developed for speciation of selenium (Se) in seeds of black mustard (Brassica nigra) grown on Se-rich soil. Size-exclusion LC-ICP MS allowed the determination of the Se distribution according to the molecular mass and the control of the species stability during extraction. The optimization of hydrophilic interaction of LC and cation-exchange HPLC resulted in analytical conditions making it possible to detect and characterize over 30 Se species using ESI MS, including a number of minor (<0.5%) metabolites. Selenoglucosinolates were found to be the most important class of species accounting for at least 15% of the total Se present and over 50% of all the metabolites. They were found particularly unstable during aqueous extraction leading to the loss of Se by volatilization as methylselenonitriles and methylselenoisothiocyanates identified using gas chromatography (GC) with the parallel ICP MS and atmospheric pressure chemical ionization (APCI) MS/MS detection. However, selenoglucosinolates could be efficiently recovered by extraction with 70% methanol. Other classes of identified species included selenoamino acids, selenosugars, selenosinapine and selenourea derivatives. The three types of reactions leading to the formation of selenometabolites were: the Se-S substitution in the metabolic pathway, oxidative reactions of -SeH groups with endogenous biomolecules, and chemical reactions, e.g., esterification, of Se-containing molecules and other biomolecules through functional groups not involving Se.

Site-specific glycoprofiling of N-linked glycopeptides using MALDI-TOF MS: strong correlation between signal strength and glycoform quantities

DEFF Research Database (Denmark)

Thaysen-Andersen, Morten; Mysling, Simon; Højrup, Peter

2009-01-01

Site-specific glycoprofiling of N-linked glycopeptides using matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) is an emerging technique, but its quantitative accuracy lacks documentation. Thus, a systematic study of widely different glycopeptides was perf......Site-specific glycoprofiling of N-linked glycopeptides using matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) is an emerging technique, but its quantitative accuracy lacks documentation. Thus, a systematic study of widely different glycopeptides...... was performed to determine the relationship between the relative abundances of the individual glycoforms and the MALDI-TOF MS signal strength. Glycopeptides derived from glycoproteins containing neutral glycans (ribonuclease B, IgG, and ovalbumin) were initially profiled and yielded excellent and reproducible...... quantitation (correlation coefficient r = 0.9958, n = 5) when evaluated against a normal phase HPLC 2-AB glycan profile. Similarly, precise quantitation was observed for various forms of N-glycans (free, permethylated, and fluorescence-labeled) using MS. In addition, three different sialoglycopeptides from...

Vergelijking van HPLC-methoden voor de bepaling van pentachloorfenol in houtmonsters

NARCIS (Netherlands)

Goewie; C.E.; Berkhoff; C.J.

1986-01-01

Een vergelijkend onderzoek is verricht naar de bruikbaarheid van verschillende detectiemethoden in combinatie met HPLC voor de analyse van pentachloorfenol in hout. In het onderzoek wordt RP-HPLC met UK en amperometrische detectie beschreven, evenals NP-HPLC met elektroneninvangdetectie. In

Analysis of sesquiterpene lactones, lignans, and flavonoids in wormwood (Artemisia absinthium L.) using high-performance liquid chromatography (HPLC)-mass spectrometry, reversed phase HPLC, and HPLC-solid phase extraction-nuclear magnetic resonance.

Science.gov (United States)

Aberham, Anita; Cicek, Serhat Sezai; Schneider, Peter; Stuppner, Hermann

2010-10-27

Today, the medicinal use of wormwood (Artemisia absinthium) is enjoying a resurgence of popularity. This study presents a specific and validated high-performance liquid chromatography (HPLC)-diode array detection method for the simultaneous determination and quantification of bioactive compounds in wormwood and commercial preparations thereof. Five sesquiterpene lactones, two lignans, and a polymethoxylated flavonoid were baseline separated on RP-18 material, using a solvent gradient consisting of 0.085% (v/v) o-phosphoric acid and acetonitrile. The flow rate was 1.0 mL/min, and chromatograms were recorded at 205 nm. The stability of absinthin was tested exposing samples to light, moisture, and different temperatures. Methanolic and aqueous solutions of absinthin were found to be stable for up to 6 months. This was also the case when the solid compound was kept in the refrigerator at -35 °C. In contrast, the colorless needles, when stored at room temperature, turned yellow. Three degradation compounds (anabsin, anabsinthin, and the new dimer 3'-hydroxyanabsinthin) were identified by HPLC-mass spectrometry and HPLC-solid-phase extraction-nuclear magnetic resonance and quantified by the established HPLC method.

On-line radioactivity detector for HPLC

International Nuclear Information System (INIS)

Kessler, M.J.

1986-01-01

Over the last ten years the technique of high performance liquid chromotography (HPLC) has become extensively employed for the separation and quantitation of various biological, organic, and inorganic substances. The use of HPLC for the separation of various metabolic compounds has become routine. The major problem of analyzing the metabolism process is that the quantitation is accomplished by the use of radioactive substrates. Until recently the only method to quantitate these radioactive compounds eluting from the HPLC was by collecting fractions at preset times, removing aliquots and quantitating in a liquid scintillation counter. Once the radioactivity present in each fraction was determined, the results were plotted on a graph and the area of each of the radioactive peaks was determined. This entire process required from 3-20 hours. The introduction of the flow through radioactivity detector enable the investigator to directly quantitate the radioactive peaks as they elute from the HPLC in real time and at about one-tenth the original cost of the previous methods. The detection limits of this technique are dependent on the residence time of the sample in the flow cell and the type of flow cell used for the analysis. Using a 2.5 ml liquid flow cell, (mixing with liquid scintillation solution), base line resolution can be obtained for peaks 1.5 minutes apart, and a sensitivity of 70 dpm for tritium and 30 dpm for carbon-14 can be achieved

Optimized LC-MS/MS Method for the High-throughput Analysis of Clinical Samples of Ivacaftor, Its Major Metabolites, and Lumacaftor in Biological Fluids of Cystic Fibrosis Patients.

Science.gov (United States)

Schneider, Elena K; Reyes-Ortega, Felisa; Li, Jian; Velkov, Tony

2017-10-15

Defects in the cystic fibrosis trans-membrane conductance regulator (CFTR) are the cause of cystic fibrosis (CF), a disease with life-threatening pulmonary manifestations. Ivacaftor (IVA) and ivacaftor-lumacaftor (LUMA) combination are two new breakthrough CF drugs that directly modulate the activity and trafficking of the defective CFTR-protein. However, there is still a dearth of understanding on pharmacokinetic/pharmacodynamic parameters and the pharmacology of ivacaftor and lumacaftor. The HPLC-MS technique for the simultaneous analysis of the concentrations of ivacaftor, hydroxymethyl-ivacaftor, ivacaftor-carboxylate, and lumacaftor in biological fluids in patients receiving standard ivacaftor or ivacaftor-lumacaftor combination therapy has previously been developed by our group and partially validated to FDA standards. However, to allow the high-throughput analysis of a larger number of patient samples, our group has optimized the reported method through the use of a smaller pore size reverse-phase chromatography column (2.6 µm, C8 100 Å; 50 x 2.1 mm) and a gradient solvent system (0-1 min: 40% B; 1-2 min: 40-70% B; 2-2.7 min: held at 70% B; 2.7-2.8 min: 70-90% B; 2.8-4.0 min: 90% B washing; 4.0-4.1 min: 90-40% B; 4.1-6.0 min: held at 40% B) instead of an isocratic elution. The goal of this study was to reduce the HPLC-MS analysis time per sample dramatically from ~15 min to only 6 min per sample, which is essential for the analysis of a large amount of patient samples. This expedient method will be of considerable utility for studies into the exposure-response relationships of these breakthrough CF drugs.

Development and validation of an LC-MS/MS method for the quantification of tiamulin, trimethoprim, tylosin, sulfadiazine and sulfamethazine in medicated feed.

Science.gov (United States)

Patyra, Ewelina; Nebot, Carolina; Gavilán, Rosa Elvira; Cepeda, Alberto; Kwiatek, Krzysztof

2018-01-22

A new multi-compound method for the analysis of veterinary drugs, namely tiamulin, trimethoprim, tylosin, sulfadiazine and sulfamethazine was developed and validated in medicated feeds. After extraction, the samples were centrifuged, diluted in Milli-Q water, filtered and analysed by high performance liquid chromatography coupled to tandem mass spectrometry. The separation of the analytes was performed on a biphenyl column with a gradient of 0.1% formic acid in acetonitrile and 0.1% formic acid in Milli-Q water. Quantitative validation was done in accordance with the guidelines laid down in European Commission Decision 2002/657/EC. Method performances were evaluated by the following parameters: linearity (R 2  tiamulin, tylosin and sulfamethazine were detected at the concentration levels declared by the manufacturers. The developed method can therefore be successfully used to routinely control the content and homogeneity of these antibacterial substances in medicated feed. Abbreviations AAFCO - Association of American Feed Control Officials; TYL - tylosin; TIAM - tiamulin fumarate; TRIM - trimethoprim; SDZ - sulfadiazine; SMZ - sulfamethazine; UV - ultraviolet detector; FLD - fluorescence detector; HPLC - high performance liquid chromatography; MS/MS - tandem mass spectrometry; LOD - limit of detection; LOQ - limit of quantification; CV - coefficient of variation; SD - standard deviation; U - uncertainty.

Identification, characterization and quantification of new impurities by LC-ESI/MS/MS and LC-UV methods in rivastigmine tartrate active pharmaceutical ingredient.

Science.gov (United States)

Thomas, Saji; Shandilya, Sanjeev; Bharati, Amber; Paul, Saroj Kumar; Agarwal, Ashutosh; Mathela, Chandra S

2012-01-05

Six impurities were detected at trace level in rivastigmine tartrate drug substance by a newly developed high performance liquid chromatography method. Three impurities were characterized rapidly and three impurities were found to be unknown. The unknown impurities were enriched and identified with a combination of semi-preparative HPLC and LC/MS/MS techniques. Proposed structures were further confirmed by characterization using NMR, FT-IR, and EA techniques of impurity standards. Based on the spectroscopic, spectrometric and elemental analysis data unknown impurities were characterized as 3-[1-(dimethylamino)ethyl]phenyl N-ethyl-N-methyl carbamate N-oxide, ethyl-methyl-carbamic acid 4-(1-dimethylamino-ethyl)-phenyl ester and ethyl-methyl-carbamic acid 2-(1-dimethylamino-ethyl)-phenyl ester. A plausible mechanism for the formation of these impurities is also proposed. The method was validated according to ICH guidelines for fourteen impurities to demonstrate specificity, precision, linearity, accuracy and stability indicating nature of the method. Regression analysis showed correlation coefficient value greater than 0.999 for rivastigmine tartrate and its impurities. Accuracy of the method was established based on the recovery obtained between 93.41 and 113.33% for all impurities. Copyright © 2011 Elsevier B.V. All rights reserved.

Speciation of selenoamino acids, selenonium ions and inorganic selenium by ion exchange HPLC with mass spectrometric detection and its application to yeast and algae

DEFF Research Database (Denmark)

Larsen, Erik Huusfeldt; Hansen, M.; Fan, T.

2001-01-01

Cation and anion exchange HPLC were used to separate a mixture of 12 selenium species comprising selenoamino acids, selenonium ions and inorganic selenium. The cationic species were separated from each other and from the co-injected anions using a cation exchange column with gradient elution...... by aqueous pyridinium formate at pH similar to 3 as the mobile phase. The anionic species were separated using an anion exchange column with isocratic elution by an aqueous salicylate-TRIS mobile phase at pH 8.5. The separated selenium species were detected as Se-80 by ICP-dynamic reaction cell (DRC...... acid extract of Chlorella algae contained dimethylselenonium propionate (DMSeP), which was verified by HPLC-ES-MS. Se-allylselenocysteine and selenoethionine was detected at the low ng g(-1) concentration level based on co-chromatography with the standard substances spiked to the algal extract....

Comparison of VOC measurements made by PTR-MS, adsorbent tubes-GC-FID-MS and DNPH derivatization-HPLC during the Sydney Particle Study, 2012: a contribution to the assessment of uncertainty in routine atmospheric VOC measurements

Science.gov (United States)

Dunne, Erin; Galbally, Ian E.; Cheng, Min; Selleck, Paul; Molloy, Suzie B.; Lawson, Sarah J.

2018-01-01

Understanding uncertainty is essential for utilizing atmospheric volatile organic compound (VOC) measurements in robust ways to develop atmospheric science. This study describes an inter-comparison of the VOC data, and the derived uncertainty estimates, measured with three independent techniques (PTR-MS, proton-transfer-reaction mass spectrometry; GC-FID-MS, gas chromatography with flame-ionization and mass spectrometric detection; and DNPH-HPLC, 2,4-dinitrophenylhydrazine derivatization followed by analysis by high-performance liquid chromatography) during routine monitoring as part of the Sydney Particle Study (SPS) campaign in 2012. Benzene, toluene, C8 aromatics, isoprene, formaldehyde and acetaldehyde were selected for the comparison, based on objective selection criteria from the available data. Bottom-up uncertainty analyses were undertaken for each compound and each measurement system. Top-down uncertainties were quantified via the inter-comparisons. In all seven comparisons, the correlations between independent measurement techniques were high with R2 values with a median of 0.92 (range 0.75-0.98) and small root mean square of the deviations (RMSD) of the observations from the regression line with a median of 0.11 (range 0.04-0.23 ppbv). These results give a high degree of confidence that for each comparison the response of the two independent techniques is dominated by the same constituents. The slope and intercept as determined by reduced major axis (RMA) regression gives a different story. The slopes varied considerably with a median of 1.25 and a range of 1.16-2.01. The intercepts varied with a median of 0.04 and a range of -0.03 to 0.31 ppbv. An ideal comparison would give a slope of 1.00 and an intercept of 0. Some sources of uncertainty that are poorly quantified by the bottom-up uncertainty analysis method were identified, including: contributions of non-target compounds to the measurement of the target compound for benzene, toluene and isoprene by

Analytical developments in ICP-MS for arsenic and selenium speciation. Application to granitic waters

International Nuclear Information System (INIS)

Garraud, Herve

1999-01-01

Nuclear waste storage in geological areas needs the understanding of the physico-chemistry of groundwaters interactions with surrounding rocks. Redox potential measurements and speciation, calculated from geochemical modelling are not significant for the determination of water reactivity. We have thus chosen to carry out experimental speciation by developing sensitive analytical tools with respect of specie chemical identity. We have studied two redox indicators from reference sites (thermal waters from Pyrenees, France): arsenic and selenium. At first, we have determined the concentrations in major ions (sulphide, sulphate, chloride, fluoride, carbonate, Na, K, Ca). Speciation was conducted by HPLC hyphenated to quadrupole ICP-MS and high resolution ICP-MS. These analyses have shown the presence of two new arsenic species in solution, in addition of a great reactivity of these waters during stability studies. A sampling, storage and analysis method is described. (author) [fr

Direct 13C NMR Detection in HPLC Hyphenation Mode

DEFF Research Database (Denmark)

Wubshet, Sileshi Gizachew; Johansen, Kenneth; Nyberg, Nils

2012-01-01

Solid phase extraction (SPE) was introduced as a crucial step in the HPLC-SPE-NMR technique to enable online analyte enrichment from which proton-detected NMR experiments on submicrogram amounts from complex mixtures were possible. However, the significance of direct-detected (13)C NMR experiments...... application of HPLC-SPE-NMR analysis using direct-detected (13)C NMR spectra. HPLC column loading, accumulative SPE trappings, and the effect of different elution solvents were evaluated and optimized. A column loading of approximately 600 mug of a prefractionated triterpenoid mixture, six trappings...

A clinical assay for the measurement of milrinone in plasma by HPLC mass spectrometry.

Science.gov (United States)

Chihoho, B; Sage, A B; Smolenski, R T; Vazir, A; Rose, M L; Banner, N R; Leaver, N V

2012-05-01

Milrinone is a bipyridine phosphodiesterase inhibitor with positive inotropic and vasodilatory effects. As interest in longer term use of intravenous therapy increases, it becomes essential to monitor its plasma concentration owing to a narrow therapeutic range, an increased half-life in renal failure and toxicity associated with high levels. A high-performance liquid chromatography (HPLC) method with mass (MS) detection using a triple quadrupole mass spectrometer is presented. The method was compared with the UV/HPLC method and validated according to current international guidelines. Coefficients of variation of less than 7.5% were obtained across the therapeutic range and 18.3% at 2.4 ng/mL, the lower limit of quantitation. Plasma from 13 cardiac surgery patients receiving standard intravenous doses of milrinone were measured. Eight patients achieved therapeutic milrinone levels within 3-4 h post start of infusion, one was borderline sub-therapeutic and four patients achieved levels that were above the upper limit of the therapeutic range and potentially toxic. This method offers high sensitivity, is rapid, easy to use and requires minimal amount of sample. We believe this method could become the reference procedure for clinical monitoring of milrinone and help to improve the safety of the use of this drug in patients with cardiac failure. Copyright © 2011 John Wiley & Sons, Ltd.

HPLC bottom-up MS-based proteomics for mapping of specific proteins in several European spring barley varieties

Czech Academy of Sciences Publication Activity Database

Flodrová, Dana; Benkovská, Dagmar; Laštovičková, Markéta; Bobálová, Janette

2015-01-01

Roč. 73, č. 1 (2015), s. 71-77 ISSN 0361-0470 R&D Projects: GA ČR(CZ) GPP503/12/P395 Institutional support: RVO:68081715 Keywords : barley * gel electrophoresis * MALDI-TOF/TOF MS * protein profile * RP liquid chromatography Subject RIV: CB - Analytical Chemistry, Separation Impact factor: 0.492, year: 2015

Profiling LC-DAD-ESI-TOF MS method for the determination of phenolic metabolites from avocado (Persea americana).

Science.gov (United States)

Hurtado-Fernández, Elena; Carrasco-Pancorbo, Alegría; Fernández-Gutiérrez, Alberto

2011-03-23

A powerful HPLC-DAD-ESI-TOF MS method was established for the efficient identification of the chemical constituents in the methanolic extracts of avocado (Persea americana). Separation and detection conditions were optimized by using a standard mix containing 39 compounds belonging to phenolic acids and different categories of flavonoids, analytes that could be potentially present in the avocado extracts. Optimum LC separation was achieved on a Zorbax Eclipse Plus C18 analytical column (4.6×150 mm, 1.8 μm particle size) by gradient elution with water+acetic acid (0.5%) and acetonitrile as mobile phases, at a flow rate of 1.6 mL/min. The detection was carried out by ultraviolet-visible absorption and ESI-TOF MS. The developed method was applied to the study of 3 different varieties of avocado, and 17 compounds were unequivocally identified with standards. Moreover, around 25 analytes were tentatively identified by taking into account the accuracy and isotopic information provided by TOF MS.

Speciation of arsenic in water, sediment, and plants of the Moira watershed, Canada, using HPLC coupled to high resolution ICP-MS

Energy Technology Data Exchange (ETDEWEB)

Zheng, Jian; Hintelmann, Holger; Dimock, Brian; Dzurko, Mark Stephen [Department of Chemistry, Trent University, 1600 West Bank Drive, K9J 7B8, Peterborough, Ontario (Canada)

2003-09-01

High-performance liquid chromatography (HPLC) coupled with high-resolution sector field ICP-MS was applied to the speciation of arsenic in environmental samples collected from the Moira watershed, Ontario, Canada. Arsenic contamination in Moira River and Moira Lake from historic gold mine operations is of increasing environmental concern to the local community. In this study, the current arsenic contamination status in water, sediment, and plants was investigated. Elevated levels of arsenic in the surface water of up to 75 ng mL{sup -1} in Moira River and 50 ng mL{sup -1} in Moira Lake were detected, 98% of which was present as arsenate. High concentrations of arsenic (>300 ng mL{sup -1}), mainly present as arsenite, were detected in sediment porewaters. A sediment profile of As from the West basin of Moira Lake showed lower As concentrations compared with data from the 1990s. An optimized extraction procedure using a phosphoric acid-ascorbic acid mixture demonstrated that an unknown ''As-complex'' which may consist of As, sulfide and organic matter is potentially responsible for the release of arsenite from the sediment to the overlying water column. Arsenic concentrations in plant samples ranged from 2.6 to 117 mg kg{sup -1}, dry weight. Accumulation of arsenic was observed in submerged plants collected from Moira River and Moira Lake. Only a small part of the arsenic (6.3-16.1%) in the plants was extractable with methanol-water (9:1), and most of this arsenic (70-93%) was inorganic arsenic. A variety of organic arsenic compounds, including simple methylated compounds (methylarsonic acid and dimethylarsinic acid), trimethylarsine oxide, and tetramethylarsonium cation were detected at trace levels. No arsenobetaine and arsenocholine was found in any plant sample. An unknown compound, most probably an arsenosugar was detected in the two submerged plants, coontail (Ceratophyllum demersum) and long-stemmed waterwort (Elatine triandra). These

HPLC-HG-AFS determination of arsenic species in acute promyelocytic leukemia (APL) plasma and blood cells.

Science.gov (United States)

Guo, Meihua; Wang, Wenjing; Hai, Xin; Zhou, Jin

2017-10-25

Arsenic trioxide (ATO) has been successfully used in the treatment of acute promyelocytic leukemia (APL). To clarify the arsenic species in APL patients, high performance liquid chromatography-hydride generation-atomic fluorescence spectrometry (HPLC-HG-AFS) and HG-AFS methods were developed and validated to quantify the plasma concentrations of inorganic arsenic (As(III) and As(V)) and methylated metabolites (MMA and DMA), and the total amounts of arsenic in blood cells and plasma. Blood cells and plasma were digested with mixtures of HNO 3 H 2 O 2 and analyzed by HG-AFS. For arsenic speciation, plasma samples were prepared with perchloric acid to precipitate protein. The supernatant was separated on an anion-exchange column within 6min with isocratic elution using 13mM CH 3 COONa, 3mM NaH 2 PO 4 , 4mM KNO 3 and 0.2mM EDTA-2Na. The methods provided linearity range of 0.2-20ng/mL for total arsenic and 2.0-50ng/mL for four arsenic species. The developed methods for total arsenic and arsenic species determination were precise and accurate. The spiked recoveries ranged from 81.2%-108.6% and the coefficients of variation for intra- and inter-batch precision were less than 9.3% and 12.5%, respectively. The developed methods were applied successfully for the assay of total arsenic and arsenic species in 5 APL patients. The HPLC-HG-AFS may be a good alternative for arsenic species determination in APL patients with its simplicity and low-cost in comparison with HPLC-ICP-MS. Copyright © 2017 Elsevier B.V. All rights reserved.

72 - 80_Aminu_HPLC1

African Journals Online (AJOL)

pc

HPLC, Gymnema sylvestre, carbohydrate hydrolyzing enzymes, lipid a chronic .... Method. Test for Tannins and Flavonoids was by. Trease and Evans (2002). Soluble Starch ... Fenton reaction was quantified using 2- deoxyribose oxidative ...

Comparison of VOC measurements made by PTR-MS, adsorbent tubes–GC-FID-MS and DNPH derivatization–HPLC during the Sydney Particle Study, 2012: a contribution to the assessment of uncertainty in routine atmospheric VOC measurements

Directory of Open Access Journals (Sweden)

E. Dunne

2018-01-01

Full Text Available Understanding uncertainty is essential for utilizing atmospheric volatile organic compound (VOC measurements in robust ways to develop atmospheric science. This study describes an inter-comparison of the VOC data, and the derived uncertainty estimates, measured with three independent techniques (PTR-MS, proton-transfer-reaction mass spectrometry; GC-FID-MS, gas chromatography with flame-ionization and mass spectrometric detection; and DNPH–HPLC, 2,4-dinitrophenylhydrazine derivatization followed by analysis by high-performance liquid chromatography during routine monitoring as part of the Sydney Particle Study (SPS campaign in 2012. Benzene, toluene, C8 aromatics, isoprene, formaldehyde and acetaldehyde were selected for the comparison, based on objective selection criteria from the available data. Bottom-up uncertainty analyses were undertaken for each compound and each measurement system. Top-down uncertainties were quantified via the inter-comparisons. In all seven comparisons, the correlations between independent measurement techniques were high with R2 values with a median of 0.92 (range 0.75–0.98 and small root mean square of the deviations (RMSD of the observations from the regression line with a median of 0.11 (range 0.04–0.23 ppbv. These results give a high degree of confidence that for each comparison the response of the two independent techniques is dominated by the same constituents. The slope and intercept as determined by reduced major axis (RMA regression gives a different story. The slopes varied considerably with a median of 1.25 and a range of 1.16–2.01. The intercepts varied with a median of 0.04 and a range of −0.03 to 0.31 ppbv. An ideal comparison would give a slope of 1.00 and an intercept of 0. Some sources of uncertainty that are poorly quantified by the bottom-up uncertainty analysis method were identified, including: contributions of non-target compounds to the measurement of the target compound for

Quantitative analysis of iridoids, secoiridoids, xanthones and xanthone glycosides in Gentiana lutea L. roots by RP-HPLC and LC-MS.

Science.gov (United States)

Aberham, Anita; Schwaiger, Stefan; Stuppner, Hermann; Ganzera, Markus

2007-11-05

The here described HPLC-method enables the determination of all major, currently known bioactive compounds in gentian roots. A separation of iridoids (loganic acid), secoiridoids (swertiamarin, gentiopicroside, amarogentin, sweroside), xanthones (gentisin, isogentisin) and two xanthone glycosides (gentiosides) was possible on RP-18 column material, using 0.025% aqueous TFA, acetonitrile and n-propanol as mobile phase. The method is sensitive (LODlutea samples showed that gentiopicroside is the most dominant compound in the specimens (4.46-9.53%), followed by loganic acid (0.10-0.76%), swertiamarin (0.21-0.45%) and the xanthone glycosides. Gentisin and isogentisin were found in much lower concentrations between 0.02 and 0.11%, respectively.

Simultaneous separation and identification of oligomeric procyanidins and anthocyanin-derived pigments in raw red wine by HPLC-UV-ESI-MSn.

Science.gov (United States)

Pati, S; Losito, I; Gambacorta, G; La Notte, E; Palmisano, F; Zambonin, P G

2006-07-01

Samples of raw red wine (Primitivo di Manduria, Apulia, Southern Italy) were analysed without any pre-treatment (except 1:2 dilution with water) using HPLC with detection based on UV absorbance and Electrospray Ionisation Sequential Mass Spectrometry (ESI-MSn, with n = 1-3) in a series configuration. In particular, absorbance at 520 nm was monitored for UV detection in order to identify pigments responsible for wine colour. On the other hand, two subsequent stages of MS detection based on positive ions were adopted. The first consisted of an explorative MS acquisition, aimed at the individuation of the m/z ratios for positively charged compounds; the second was based on fragmentation of the detected ions within an ion trap analyser, followed by MS/MS and, if required, MS3 acquisitions. The synergy between UV detection and MSn analysis led to the identification of 41 pigments, which can be classified into five groups: grape anthocyanins, pyranoanthocyanins, vinyl-linked anthocyanin-flavanol pigments, ethyl-bridged anthocyanin-flavanol pigments and flavanol-anthocyanin compounds. Many isomeric and oligomeric structures were found within each group. A further class of compounds, not absorbing in the visible spectrum, could be also characterised by ESI-MSn and corresponded to B-type procyanidins, i.e. proanthocyanidins arising from C4-->C8/C4-->C6 couplings between catechin or epicatechin units. In particular, oligomeric structures (from dimers to pentamers), often present with several isomers, were identified and their fragmentation patterns clarified.

Steroids in porcine follicular fluid: analysis by HPLC, capillary CG and capillary CG/MS after purification on SEP-PAK C18 and ion exchange chromatography.

Science.gov (United States)

Khalil, M W; Lawson, V

1983-04-01

Steroids in porcine follicular fluid have been concentrated by reverse phase chromatography in SEP-PAK C18 and purified further on the cation exchanger SP-Sephadex C-25. Fractionation into unconjugated neutral and phenolic steroids, glucuronides and sulfates was carried out on triethylaminohydroxypropyl Sephadex LH-20 (TEAP-LH-20). The unconjugated neutral fraction was analysed by high pressure liquid chromatography (HPLC) on a C18 radial cartridge 5 mm I.D.; 10 mu, or on a C18 5 mu RESOLVE column, and by capillary gas chromatography (GC) on a 12 M OV-1 cross linked fused silica column. Testosterone, progesterone and androstenedione were the major steroids detected by HPLC monitored at 254 nm, although 17- hydroxy-, 20 alpha-dihydro- and 20 beta-dihydroprogesterone were also present. Pregnenolone, pregnanediol, dehydroepiandrosterone, 17-hydroxypregnenolone and androsterone were detected by capillary CG as their 0-methyloxime trimethylsilyether derivatives. Further confirmation of structure was provided by complete mass spectral data or by selective ion monitoring (SIM).

A Modified LC/MS/MS Method with Enhanced Sensitivity for the Determination of Scopolamine in Human Plasma

Science.gov (United States)

Wang, Zuwei; Vaksman, Zalman; Putcha, Lakshmi

2008-01-01

Intranasal scopolamine is a choice drug for the treatment of motion sickness during space flight because of its quick onset of action, short half-life and favorable sideeffects profile. The dose administered usually ranges between 0.1 and 0.4 mg. Such small doses make it difficult to detect concentrations of scopolamine in biological fluids using existing sensitive LC/MS/MS method, especially when the biological sample volumes are limited. To measure scopolamine in human plasma to facilitate pharmacokinetic evaluation of the drug, we developed a sensitive LC/MS/MS method using 96 well micro elution plates for solid phase extraction (SPE) of scopolamine in human plasma. Human plasma (100-250 micro L) were loaded onto Waters Oasis HLB 96 well micro elution plate and eluted with 50 L of organic solvent without evaporation and reconstitution. HPLC separation of the eluted sample was performed using an Agilent Zorbax SB-CN column (50 x 2.1 mm) at a flow rate of 0.2 mL/min for 3 minutes. The mobile phase for separation was 80:20 (v/v) methanol: ammonium acetate (30 mM) in water. Concentrations of scopolamine were determined using a Micromass Quattro Micro(TM) mass spectrometer with electrospray ionization (ESI). ESI mass spectra were acquired in positive ion mode with multiple reaction monitoring for the determination of scopolamine m/z = 304.2 right arrow 138.1 and internal standard hyoscyamine m/z = 290.2 right arrow 124.1. The method is rapid, reproducible, specific and has the following parameters: scopolamine and the IS are eluted at about 1.1 and 1.7 min respectively. The linear range is 25-10000 pg/mL for scopolamine in human plasma with correlation coefficients greater than 0.99 and CV less than 0.5%. The intra-day and inter-day CVs are less than 15% for quality control samples with concentrations of 75,300, and 750 pg/mL of scopolamine in human plasma. SPE using 96 well micro elution plates allows rapid sample preparation and enhanced sensitivity for the LC/MS/MS

Reverse-phase HPLC analysis of human alpha crystallin.

Science.gov (United States)

Swamy, M S; Abraham, E C

1991-03-01

A rapid and highly sensitive reverse-phase HPLC (RP-HPLC) method was used to separate crystallin subunits from human alpha crystallin. Three distinct peaks were separated; by electrophoretic and immunological analyses the first and second peaks were identified as alpha B and alpha A respectively. On the other hand, peak 3 appeared to be a modified form of alpha crystallin. The ratio of alpha A and alpha B proteins was 3:1 in 1 day old lenses which gradually changed to 2:1 in 17 year old lenses and to 1:1 in the 50 and 82 year old whole lenses and 82 year old lens cortex, with a concomitant increase in the modified alpha, suggesting that alpha A subunits are relatively more involved in aggregation. Analysis of the 82 year old lens nucleus also supported this conclusion. The RP-HPLC analysis of the HMW aggregate fraction showed substantial enrichment of the modified alpha. The alpha A and alpha B subunits independently reassociated to form polymeric alpha crystallin whereas the modified alpha reassociated to form HMW aggregates as shown by molecular sieve HPLC. Hence it appears that the HMW aggregate peak was constituted by modified alpha crystallin. Only in the peak 3 material the 280 nm absorbance was about 2-fold higher than what was expected from the actual protein content. The data suggest that the changes induced by post-translational modifications may have some role in the formation of modified alpha. The present RP-HPLC method is useful in separating these modified alpha from the unmodified alpha A and alpha B subunits.

Optimizing Chromatographic Separation: An Experiment Using an HPLC Simulator

Science.gov (United States)

Shalliker, R. A.; Kayillo, S.; Dennis, G. R.

2008-01-01

Optimization of a chromatographic separation within the time constraints of a laboratory session is practically impossible. However, by employing a HPLC simulator, experiments can be designed that allow students to develop an appreciation of the complexities involved in optimization procedures. In the present exercise, a HPLC simulator from "JCE…

Development of a new rapid HPLC method for the fractionation of histones

International Nuclear Information System (INIS)

Gurley, L.R.; Valdez, J.G.; Prentice, D.A.; Spall, W.D.

1983-01-01

To study histone functions, it is necessary to fractionate the histones into their five classes (H1, H2A, H2B, H3 and H4) and then to subfractionate these classes into variants having slightly different primary structures and into different phosphorylated and acetylated forms. With the advent of high-performance liquid chromatography (HPLC), it was hoped that laborious and time-consuming conventional methods could be replaced by a simple, rapid, high-resolving HPLC method for fractionating histones. However, problems of irreversible adsorption of the histones to HPLC column packings discouraged this development. Our laboratory has now determined that the strong adsorption of histones to HPLC columns results from two different forces: (1) polar interactions between the histones and the silanol groups of silica-based HPLC column packing, and (2) hydrophobic interactions between the histones and the bound organic phase of the column packings. By minimizing these forces, we have succeeded in developing an HPLC method suitable for histone studies

Anthocyanins standards (cyanidin-3-O-glucoside and cyanidin-3-O-rutinoside isolation from freeze-dried açaí (Euterpe oleraceae Mart. by HPLC

Directory of Open Access Journals (Sweden)

Ana Cristina Miranda Senna Gouvêa

2012-03-01

Full Text Available Availability of analytical standards is a critical aspect in developing methods for quantitative analysis of anthocyanins. The anthocyanins cyanidin-3-O-glucoside and cyanidin-3-O-rutinoside were isolated from samples of freeze-dried açaí (Euterpe oleraceae Mart., which is a round and purple well-known palm fruit in Brazil, and then used as standards. The isolation of the anthocyanins was performed by High Performance Liquid Chromatography (HPLC, using an adapted six-channel selection valve. The identification of anthocyanin pigments in açaí was based on mass spectrometric data for molecular ions and MS-MS product ions and on previous published data. After the collection procedure, standards with a high purity grade were obtained and an external standard curve of each anthocyanin was plotted.

Kvalitativní a kvantitativní analýza sacharidů v hroznech a vínu pomocí HPLC s MS a ELS detekcí

Czech Academy of Sciences Publication Activity Database

Čmelík, Richard; Flodrová, Dana

2014-01-01

Roč. 108, č. 8 (2014), s. 772-773 ISSN 0009-2770. [Sjezd chemických společností /66./. 07.09.2014-10.09.2014, Ostrava] Grant - others:GA AV ČR(CZ) R200311405 Institutional support: RVO:68081715 Keywords : carbohydrate * wine * HPLC Subject RIV: CB - Analytical Chemistry, Separation

Identification and quantification of stilbenes in some Tunisian red wines using UPLC-MS and HPLC-DAD

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Kamel Arraki

2017-06-01

Full Text Available Seven Tunisian red wines mainly from the Mornag appellation were analyzed for resveratrol and analogues. The wines of each variety were evaporated, concentrated, and then subjected to fractionation and purification using XAD16 and DOWEX column chromatography. In addition to resveratrol, seven stilbenes were identified by UPLC-MS. The stilbenes derived were shown to be piceatannol, piceid, a-viniferin, e-viniferin, hopeaphenol and isohopeaphenol. From the point of view of the presence of resveratrol derivatives, one wine, Sidi Zahia, was the richest qualitatively.

Fragment screening for drug leads by weak affinity chromatography (WAC-MS).

Science.gov (United States)

Ohlson, Sten; Duong-Thi, Minh-Dao

2018-02-23

Fragment-based drug discovery is an important tool for design of small molecule hit-to-lead compounds against various biological targets. Several approved drugs have been derived from an initial fragment screen and many such candidates are in various stages of clinical trials. Finding fragment hits, that are suitable for optimisation by medicinal chemists, is still a challenge as the binding between the small fragment and its target is weak in the range of mM to µM of K d and irrelevant non-specific interactions are abundant in this area of transient interactions. Fortunately, there are methods that can study weak interactions quite efficiently of which NMR, surface plasmon resonance (SPR) and X-ray crystallography are the most prominent. Now, a new technology based on zonal affinity chromatography, weak affinity chromatography (WAC), has been introduced which has remedied many of the problems with other technologies. By combining WAC with mass spectrometry (WAC-MS), it is a powerful tool to identify binders quantitatively in terms of affinity and kinetics either from fragment libraries or from complex mixtures of biological extracts. As WAC-MS can be multiplexed by analysing mixtures of fragments (20-100 fragments) in one sample, this approach yields high throughput, where a whole library of e.g. >2000 fragments can be analysed quantitatively within a day. WAC-MS is easy to perform, where the robustness and quality of HPLC is fully utilized. This review will highlight the rationale behind the application of WAC-MS for fragment screening in drug discovery. Copyright © 2018 Elsevier Inc. All rights reserved.

Taoistický pohled na trénování ve fotbalu a triatlonu

OpenAIRE

Skála, Tomáš

2009-01-01

Nazev: Taoisticky pohled na trenovani ve fotbalu a triatlonu Cile prace: Objasnit pojmy taoismus a Tao, pomoci jejich charakteristiky osvetlit taoisticke vnimani sebe sama, okolniho sveta a pohybove aktivity, s naslednou aplikaci na konkretni sporty fotbal a triatlon. Metody: Deskripce, analyza, spekulace Klicova slova: Taoismus, Tao, Cchi, Jin a Jang, Wu-Wej, fotbal, triatlon, zacatecnicka mysl SUMMARY Title: The taoistic view in the football and triatlon training Objective: To explain terms...

Comparison of high-performance liquid chromatography/tandem mass spectrometry and high-performance liquid chromatography/photo-diode array detection for the quantitation of carotenoids, retinyl esters, α-tocopherol and phylloquinone in chylomicron-rich fractions of human plasma.

Science.gov (United States)

Kopec, Rachel E; Schweiggert, Ralf M; Riedl, Ken M; Carle, Reinhold; Schwartz, Steven J

2013-06-30

Bioavailability of essential lipophilic micronutrients and carotenoids is of utmost interest for human health, as the consumption of these compounds may help alleviate major nutritional deficiencies, cardiovascular disease, and cancer. High-performance liquid chromatography/photo-diode array detection (HPLC-PDA) and high-performance liquid chromatography/tandem mass spectrometry (HPLC/MS/MS) were compared for the quantitative analysis of α- and β-carotene, β-cryptoxanthin, lutein, lycopene, α-tocopherol, phylloquinone, and several retinyl esters from chylomicron-containing triglyceride rich lipoprotein (TRL) fractions of human plasma obtained from two clinical trials. After selecting an efficient extraction method for the analytes, both the HPLC/PDA and the HPLC/MS/MS methods were developed and several parameters validated using an HP 1200 series HPLC system interfaced with a HP 1200 series diode-array detector (Agilent Technologies, Santa Clara, CA, USA) and a QTRAP 5500 (AB Sciex, Foster City, CA, USA) via an atmospheric pressure chemical ionization (APCI) probe operated in positive ion mode. For lycopene, α- and β-carotene, HPLC/MS/MS was up to 37 times more sensitive than HPLC-PDA. PDA detection was shown to be up to 8 times more sensitive for lutein. MS/MS signals were enhanced by matrix components for lutein and β-cryptoxanthin, as determined by referencing to the matrix-independent PDA signal. In contrast, matrix suppression was observed for retinyl palmitate, α-carotene, and β-carotene. Both detectors showed similar suitability for α-tocopherol, lycopene and retinyl palmitate (representing ~73% of total retinyl esters). MS/MS exclusively allowed the quantitation of minor retinyl esters, phylloquinone, and (Z)-lycopene isomers. HPLC/MS/MS was more sensitive than HPLC-PDA for six of the eight analytes and represents a powerful tool for the analysis of chylomicron samples and potentially other biological samples of limited sample size. When internal

Methods and applications of HPLC-AMS (WBio 5)

International Nuclear Information System (INIS)

Bucholz, B A; Clifford, A J; Duecker, S R; Lin, Y; Vogel, J S

1999-01-01

Pharmacokinetics of physiologic doses of nutrients, pesticides, and herbicides can easily be traced in humans using a(sup 14)C-labelled compound. Basic kinetics can be monitored in blood or urine by measuring the elevation in the(sup 14)C content above the control predose tissue and converting to equivalents of the parent compound. High Performance Liquid Chromatography (HPLC) is an excellent method for the chemical separation of complex mixtures whose profiles afford estimation of biochemical pathways of metabolism. Compounds elute from the HPLC systems with characteristic retention times and can be collected in fractions that can then be graphitized for AMS measurement. Unknowns are identified by coelution with known standards and chemical tests that reveal functional groupings. Metabolites are quantified with the(sup 14)C signal. Thoroughly accounting for the carbon inventory in the LC solvents, ion-pairing agents, samples, and carriers adds some complexity to the analysis. In most cases the total carbon inventory is dominated by carrier. Baseline background and stability need to be carefully monitored. Limits of quantitation near 10 amol of(sup 14)C per HPLC fraction are typically achieved. Baselines are maintained by limiting injected(sup 14)C activity and lt;0.17 Bq (4.5 pCi) on the HPLC column

Identification of flavonoids and hydroxycinnamic acids in pak choi varieties (Brassica campestris L. ssp. chinensis var. communis) by HPLC-ESI-MSn and NMR and their quantification by HPLC-DAD.

Science.gov (United States)

Harbaum, Britta; Hubbermann, Eva Maria; Wolff, Christian; Herges, Rainer; Zhu, Zhujun; Schwarz, Karin

2007-10-03

Twenty-eight polyphenols (11 flavonoid derivatives and 17 hydroxycinnamic acid derivatives) were detected in different cultivars of the Chinese cabbage pak choi ( Brassica campestris L. ssp. chinensis var. communis) by HPLC-DAD-ESI-MS(n). Kaempferol was found to be the major flavonoid in pak choi, glycosylated and acylated with different compounds. Smaller amounts of isorhamnetin were also detected. A structural determination was carried out by (1)H and (13)C NMR spectroscopy for the main compound, kaempferol-3-O-hydroxyferuloylsophoroside-7-O-glucoside, for the first time. Hydroxycinnamic acid derivatives were identified as different esters of quinic acid, glycosides, and malic acid. The latter ones are described for the first time in cabbages. The content of polyphenols was determined in 11 cultivars of pak choi, with higher concentrations present in the leaf blade than in the leaf stem. Hydroxycinnamic acid esters, particularly malic acid derivatives, are present in both the leaf blade and leaf stem, whereas flavonoid levels were determined only in the leaf blade.

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

NARCIS (Netherlands)

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

2016-01-01

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

[Study on the fingerprint of Morus alba from different habitats by HPLC].

Science.gov (United States)

Chen, Cheng; Li, Hong-Bo; Wang, Liu-Ping; Li, Yun-Rong; Xin, Ning

2012-12-01

To establish HPLC fingerprint of Morus alba from different habitats by HPLC and provide basis for its quality control. HPLC analysis was performed on an Agilent XDB C18 Column (4.6 mm x 250 mm, 5 microm), gradient eluted composed of acetonitrile and 0.3% phosphate acid. The column temperature was set at 35 degrees C and the flow rate was 0.5 mL/min. The detective wavelength was 290 nm. The HPLC fingerprint for 10 batches of Morus alba was studied on their similarity. There were twelve common peaks in the fingerprint. The similarity of 7 batches was above 0.9 and the other batches had low similarity. The HPLC fingerprint can be used for quality control of Morus alba with high characteristics and specificity.

Larix decidua Bark as a Source of Phytoconstituents: An LC-MS Study

Directory of Open Access Journals (Sweden)

Valeria Baldan

2017-11-01

Full Text Available Larix decidua bark is a waste of the timber industry and is widely diffused in Northern Italy. This material can be considered a good source of antioxidants and phytoconstituents with possible use in cosmetic or nutraceutical products. In this study, simple extraction of larch bark was performed using mixtures of ethanol/water. Furthermore, the phytochemical composition of larch bark extract was studied using LC-MSn methods and the main constituents were identified as flavonoids, spiro-polyphenols, and procyanidins. To confirm the identification by LC-MS semi-preparative HPLC was performed in order to isolate the main constituents and verify the structures by 1H-NMR. Antioxidant properties were studied using an in vitro approach combining DPPH assay and LC-MS in order to establish different roles of the various classes of phytochemicasl of the extract. DPPH activity of some of the isolated compounds was also assessed. The overall results indicate this waste material as a good source of antioxidant compounds, mainly procyanidins, whichresulted the most active constituents in the DPPH assay.

75 FR 47036 - Small Business Size Standards: Waiver of the Nonmanufacturer Rule

Science.gov (United States)

2010-08-04

... Spectrometry (CS-MS) Systems, High Performance Liquid Chromatography (HPLC) Systems, Gas Chromatography Mass Spectrometry (GC-MS) Systems, and, Inductively Coupled Plasma Mass Spectrometry (ICP-MS) Systems under Product...-portable CS-MS, HPLC, GC-MS, and, ICP-MS Laboratory Equipment under PSC 6640 (Laboratory Equipment and...

HPLC-ESI-MS(n) Analysis, Fed-Batch Cultivation Enhances Bioactive Compound Biosynthesis and Immune-Regulative Effect of Adventitious Roots in Pseudostellaria heterophylla.

Science.gov (United States)

Wang, Juan; Li, Jing; Li, Hongfa; Wu, Xiaolei; Gao, Wenyuan

2015-09-01

A electrospray ionization tandem mass spectrometry (ESI-MS(n)) analysis was performed in order to identify the active composition in Pseudostellaria heterophylla adventitious roots. Pseudostellarin A, C, D, and G were identified from P. heterophylla adventitious roots on the basis of LC-MS(n) analysis. The culture conditions of adventitious roots were optimized, and datasets were subjected to a partial least squares discriminant analysis (PLS-DA), in which the growth ratio and some compounds showed a positive correlation with an aeration volume of 0.3 vvm and inoculum density of 0.15 %. Fed-batch cultivation enhanced the contents of total saponin, polysaccharides, and specific oxygen uptaker rate (SOUR). The maximum dry root weight (4.728 g l(-1)) was achieved in the 3/4 Murashige and Skoog (MS) medium group. PLS-DA showed that polysaccharides contributed significantly to the clustering of different groups and showed a positive correlation in the MS medium group. The delayed-type hypersensitivity (DTH) reaction on the mice induced by 2,4-dinitrofluorobenzene (DNFB) was applied to compare the immunocompetence effects of adventitious roots (AR) with field native roots (NR) of P. heterophylla. As a result, AR possessed a similar immunoregulation function as NR.

Finding of pesticides in fashionable fruit juices by LC-MS/MS and GC-MS/MS.

Science.gov (United States)

Tran, Kevin; Eide, David; Nickols, Susan M; Cromer, Michele R; Sabaa-Srur, Armando; Smith, Robert E

2012-10-15

Products labelled as containing extracts from two mushrooms (cordyceps plus reishi) and the juices from açaí, goji, mangosteen, noni, pomegranate, and sea buckthorn have been analysed for 174 different pesticides, using the validated QuEChERS method for sample preparation and electrospray LC-MS/MS in the positive ion mode for analysis. Pesticides were found in 10 of the 21 samples analysed. Most pesticides found were below the tolerance levels (1-6 μg/g, depending on the pesticide), but some were not. This included boscalid, dimethomorph, iprovalicarb, pyridaben, pyrimethanil, and imazalil, for which there is no tolerance reported or zero tolerance in any fruit. However, genuine açaí that was harvested in the state of Pará and lyophilised in Rio de Janeiro had no detectable pesticides, when analysed by both LC-MS/MS and GC-MS/MS, which can detect 213 more pesticides and industrial chemicals. Likewise no pesticides were found in one sample each of cordyceps plus reishi, sea buckthorn and noni. Published by Elsevier Ltd.

Measuring OVOCs and VOCs by PTR-MS in an urban roadside microenvironment of Hong Kong: relative humidity and temperature dependence, and field intercomparisons

Science.gov (United States)

Cui, Long; Zhang, Zhou; Huang, Yu; Lee, Shun Cheng; Blake, Donald Ray; Ho, Kin Fai; Wang, Bei; Gao, Yuan; Wang, Xin Ming; Kwok Keung Louie, Peter

2016-12-01

Volatile organic compound (VOC) control is an important issue of air quality management in Hong Kong because ozone formation is generally VOC limited. Several oxygenated volatile organic compound (OVOC) and VOC measurement techniques - namely, (1) offline 2,4-dinitrophenylhydrazine (DNPH) cartridge sampling followed by high-performance liquid chromatography (HPLC) analysis; (2) online gas chromatography (GC) with flame ionization detection (FID); and (3) offline canister sampling followed by GC with mass spectrometer detection (MSD), FID, and electron capture detection (ECD) - were applied during this study. For the first time, the proton transfer reaction-mass spectrometry (PTR-MS) technique was also introduced to measured OVOCs and VOCs in an urban roadside area of Hong Kong. The integrated effect of ambient relative humidity (RH) and temperature (T) on formaldehyde measurements by PTR-MS was explored in this study. A Poly 2-D regression was found to be the best nonlinear surface simulation (r = 0.97) of the experimental reaction rate coefficient ratio, ambient RH, and T for formaldehyde measurement. This correction method was found to be better than correcting formaldehyde concentrations directly via the absolute humidity of inlet sample, based on a 2-year field sampling campaign at Mong Kok (MK) in Hong Kong. For OVOC species, formaldehyde, acetaldehyde, acetone, and MEK showed good agreements between PTR-MS and DNPH-HPLC with slopes of 1.00, 1.10, 0.76, and 0.88, respectively, and correlation coefficients of 0.79, 0.75, 0.60, and 0.93, respectively. Overall, fair agreements were found between PTR-MS and online GC-FID for benzene (slope = 1.23, r = 0.95), toluene (slope = 1.01, r = 0.96) and C2-benzenes (slope = 1.02, r = 0.96) after correcting benzene and C2-benzenes levels which could be affected by fragments formed from ethylbenzene. For the intercomparisons between PTR-MS and offline canister measurements by GC-MSD/FID/ECD, benzene showed good agreement

Quantitative determination of the dual COX-2/5-LOX inhibitor tryptanthrin in Isatis tinctoria by ESI-LC-MS.

Science.gov (United States)

Danz, Henning; Baumann, Dietmar; Hamburger, Matthias

2002-02-01

Isatis tinctoria L. is an old European and Chinese dye plant and anti-inflammatory herb from which the potent cyclooxygenase-2 and 5-lipoxygenase inhibitor tryptanthrin (1) (indolo-[2,1-b]-quinazoline-6,12-dione) was recently isolated as one of the active principles. An HPLC method for the quantitative analysis of the compound in plant material was developed. Reproducible extraction was achieved by accelerated solvent extraction (ASE). Detection by UV at 254 and 387 nm and by electrospray-MS were compared. The low tryptanthrin content in the herb and possible interferences required isocratic high-performance liquid chromatography coupled with electrospray-MS in single ion mode. More than 70 Isatis samples of different origin were analyzed. The tryptanthrin content in leaf samples varied from 0.56 to 16.74 x 10(-3) %.

Lipophilization and MS characterization of the main anthocyanins purified from hibiscus flowers.

Science.gov (United States)

Grajeda-Iglesias, Claudia; Salas, Erika; Barouh, Nathalie; Baréa, Bruno; Figueroa-Espinoza, Maria Cruz

2017-09-01

Hibiscus sabdariffa flowers represent an interesting source of anthocyanins, one of the most important plant pigments, which are responsible of the intense red color of the calyces, and have potential as natural colorants for food applications. Nevertheless, anthocyanins are highly hydrosoluble and unstable compounds. On this basis, the aim of this work was to increase the lipophilicity of the hibiscus anthocyanins by lipophilization, in order to obtain amphiphilic colorants, which could be easily incorporated in lipid-rich food matrices. Octanoyl derivatives of delphinidin-3-O-sambubioside and cyanidin-3-O-sambubioside were chemically obtained for the first time, and characterized by means of HPLC-ESI-MS data. Copyright © 2017. Published by Elsevier Ltd.