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Determination of Voriconazole in Human Plasma by Liquid Chromatography Tandem Mass Spectrometry: Application in Therapeutic Drug Monitoring
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作者 Waleed Alhussaini Ezzeldeen Ghanem +4 位作者 Magd Alsahly Amani Kurdi Eman Alharbi Imadul Islam Majed Aljeraisy 《American Journal of Analytical Chemistry》 2023年第9期378-389,共12页
A sensitive, accurate and robust Liquid Chromatography Tandem Mass Spectrometry method has been developed and validated to measure voriconazole trough levels in human plasma. The plasma samples were mixed with flucona... A sensitive, accurate and robust Liquid Chromatography Tandem Mass Spectrometry method has been developed and validated to measure voriconazole trough levels in human plasma. The plasma samples were mixed with fluconazole as an Internal Standard and directed to protein precipitation and drug extraction. An aliquot of 1 μl was injected into the chromatographic system and separated by the Acquity BEH C18 column at a flow rate of 0.30 ml/min in a gradient mobile phase consisting of acetonitrile, Ultrapure water (UPW), methanol and formic acid. Voriconazole was detected by a Triple Quadrupole Detector (TQD) operating on Multiple Reaction Monitoring (MRM) and a positive ion mode Electrospray ionization (ESI) Q1 mass: 350.1 m/z, Q3 mass: 281.1 m/z. Method linearity of the calibration curve (0.10 - 8.00 μg/ml) indicated a correlation coefficient r ≥ 0.99. The intra and inter-assay accuracy was within 85% - 115% and the intra and inter-assay precision was ≤5.76%. Voriconazole recovery percentage was between 97.69 - 119.62%. The method was successively applied in routine voriconazole TDM. 展开更多
关键词 VORICONAZOLE Human Plasma Liquid chromatography tandem mass spectrometry Therapeutic Drug Monitoring
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Determination of sterols in tobacco leaves by gas chromatography-tandem mass spectrometry
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作者 CHEN Qiansi LIU Pingping +7 位作者 ZHAI Niu ZHENG Qingxia XU Guoyun WANG Chen FAN Kai JIN Lifeng ZHANG Hui ZHOU Huina 《烟草科技》 EI CAS CSCD 北大核心 2018年第A01期25-32,共8页
The purpose of the study was to establish an analytical method to simultaneously determine multiple sterols in tobacco leaves rapidly and accurately.In this gas chromatography-triple quadruple tandem mass spectrometry... The purpose of the study was to establish an analytical method to simultaneously determine multiple sterols in tobacco leaves rapidly and accurately.In this gas chromatography-triple quadruple tandem mass spectrometry(GC-MS/MS)based method,various conditions for sterols extraction were assessed and the instrumental operation parameters were optimized with 5α-cholane as an internal standard.Using this method,eight plant sterols,namely lanosterol,campesterol,chenodeoxycholic acid,cholesterol,β-sitosterol,stigmasterol,dihydrotachysterol and ergosterol,were separated in less than 30 min.The linear correlation coefficients were over 0.998 9,the low detection limits were in the range of 0.010 3-0.141 4 μg/g.The recoveries were from 87.30% to 115.60%,with low standard deviations.In conclusion,this method demonstrates good repeatability,accuracy,and high sensitivity,and is best suited for rapid analysis of multiple sterols in tobacco leaves. 展开更多
关键词 TOBACCO STEROL gas chromatography-triple QUADRUPOLE tandem mass spectrometry
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The Detection of THCA Using 2-Dimensional Gas Chromatography-Tandem Mass Spectrometry in Human Fingernail Clippings: Method Validation and Comparison with Head Hair
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作者 Joseph Jones Mary Jones +1 位作者 Charles Plate Douglas Lewis 《American Journal of Analytical Chemistry》 2013年第10期1-8,共8页
Marijuana use as well as abuse is a significant public health and public safety concern in the United States and using hair to identify marijuana users and abusers has been gaining acceptance in a number of venues inc... Marijuana use as well as abuse is a significant public health and public safety concern in the United States and using hair to identify marijuana users and abusers has been gaining acceptance in a number of venues including workplace, court ordered, and substance abuse treatment monitoring. After the presentation of a fully validated 2-dimensional gas chromatography-tandem mass spectrometry method for the detection of 11-nor-9-carboxy-Δ9-tetrahydrocannabinol (THCA), the chief metabolite of the main psychoactive compound in marijuana, Δ9-tetrahydrocannabinol (THC), we evaluated the usefulness of fingernail clippings as an alternative specimen type to hair by the analysis of a set of 60 matched pairs of head hair and fingernail clippings. The limit of detection was 10 fg/mg, the limit of quantitation was 20 fg/mg, and the assay was linear from 20 fg/mg to 500 fg/mg. The intra- and inter-assay imprecision and bias studies at 4 different concentrations (50, 100, 500, and 1000 fg/mg) were acceptable where all % Target observations were within 16% of their expected concentrations and all %CV calculations were less than 13.5%. THCA was detectable in more fingernail specimens (53.3%) than hair specimens (46.7%) and the mean concentrations in nails were on average 4.9 times higher than in hair (1813 fg/mg and 364 fg/mg, respectively). The THCA concentrations in hair and nail were strongly associated (r = 0.974, P < 0.01, n = 60) and the association was significant. The study demonstrated that fingernail clippings are a suitable alternative specimen type to hair to monitor for marijuana use and abuse. 展开更多
关键词 11-Nor-9-Carboxy-Δ9-Tetrahydrocannabinol THCA Carboxy-THC HAIR Fingernail 2D-GC-MS/MS 2-Dimensional gas chromatography tandem mass spectrometry
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Pyrolysis-Gas Chromatography/Mass Spectrometry for Microstructure and Pyrolysis Pathway of Polyester-Polyether Multiblock Copolymer
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作者 罗爱芹 叶玲 +2 位作者 傅若农 谢桂阳 王显伦 《Journal of Beijing Institute of Technology》 EI CAS 2001年第1期45-50,共6页
The composition and sequence distribution of monomeric units in polyester polyether multiblock copolymer were studied by pyrolysis? gas chromatography (PGC) and pyrolysis gas chromatography/mass spectrometry (PGC/M... The composition and sequence distribution of monomeric units in polyester polyether multiblock copolymer were studied by pyrolysis? gas chromatography (PGC) and pyrolysis gas chromatography/mass spectrometry (PGC/MS). PGC was applied to study the F t curve of the multiblock copolymer and PGC/MS was used to separate and identify the pyrolyzates. DTA experiment was used to study the decomposition temperature. The results show that the beginning point of elastomer’s decomposition was about 300?℃ and the decomposition temperature of most of the sample was 550?℃. Many pyrolyzates were produced because of the breaking of weak bonds in the sample. The possible microstructure was verified and the pyrolysis pathway of the copolymer was investigated. 展开更多
关键词 thermoplastic elastomer polyester polyether multiblock copolymer pyrolysis gas chromatography/mass spectrometry copolymer pyrolysis pathway MICROSTRUCTURE pyrolyzates
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Metabolomics of gastric cancer metastasis detected by gas chromatography and mass spectrometry 被引量:13
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作者 Jin-Lian Chen,Jun-Duo Hu,Jing Fan,Jing Hong,Department of Gastroenterology,Shanghai Sixth People’s Hospital,Shanghai Jiao Tong University,Shanghai 200233,China Hui-Qing Tang,Jian-Zhong Gu,Shanghai Laboratory Animal Center,Chinese Academy of Sciences,Shanghai 201615,China 《World Journal of Gastroenterology》 SCIE CAS CSCD 2010年第46期5874-5880,共7页
AIM:To elucidate the underlying mechanisms of metastasis and to identify the metabolomic markers of gastric cancer metastasis.METHODS:Gastric tumors from metastatic and nonmetastatic groups were used in this study.Met... AIM:To elucidate the underlying mechanisms of metastasis and to identify the metabolomic markers of gastric cancer metastasis.METHODS:Gastric tumors from metastatic and nonmetastatic groups were used in this study.Metabolites and different metabolic patterns were analyzed by gas chromatography,mass spectrometry and principal components analysis (PCA),respectively.Differentiation performance was validated by the area under the curve (AUC) of receiver operating characteristic curves.RESULTS:Twenty-nine metabolites were differentially expressed in animal models of human gastric cancer.Of the 29 metabolites,20 were up-regulated and 9 were down-regulated in metastasis group compared to non-metastasis group.PCA models from the metabolite profiles could differentiate the metastatic from the nonmetastatic specimens with an AUC value of 1.0.These metabolites were mainly involved in several metabolic pathways,including glycolysis (lactic acid,alaline),serine metabolism (serine,phosphoserine),proline metabolism (proline),glutamic acid metabolism,tricarboxylic acid cycle (succinate,malic acid),nucleotide metabolism (pyrimidine),fatty acid metabolism (docosanoic acid,and octadecanoic acid),and methylation(glycine).The serine and proline metabolisms were highlighted during the progression of metastasis.CONCLUSION:Proline and serine metabolisms play an important role in metastasis.The metabolic profiling of tumor tissue can provide new biomarkers for the treatment of gastric cancer metastasis. 展开更多
关键词 gasTRIC cancer METASTASIS METABOLITE Metabolomics gas chromatography and mass spectrometry
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Gas chromatography/mass spectrometry based metabolomic study in a murine model of irritable bowel syndrome 被引量:8
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作者 Lei-Min Yu Ke-Jia Zhao +2 位作者 Shuang-Shuang Wang Xi Wang Bin Lu 《World Journal of Gastroenterology》 SCIE CAS 2018年第8期894-904,共11页
AIM To study the role of microbial metabolites in the modulation of biochemical and physiological processes in irritable bowel syndrome(IBS).METHODS In the current study, using a metabolomic approach, we analyzed the ... AIM To study the role of microbial metabolites in the modulation of biochemical and physiological processes in irritable bowel syndrome(IBS).METHODS In the current study, using a metabolomic approach, we analyzed the key metabolites differentially excreted in the feces of control mice and mice with IBS, with or without Clostridium butyricum(C. butyricum) treatment. C57 BL/6 mice were divided into control, IBS, and IBS + C. butyricum groups. In the IBS and IBS + C. butyricum groups, the mice were subjected to water avoidance stress(WAS) for 1 h/d for ten days. Gas chromatography/mass spectrometry(GC-MS) together with multivariate analysis was employed to compare the fecal samples between groups. RESULTS WAS exposure established an appropriate model of IBS in mice, with symptoms of visceral hyperalgesia and diarrhea. The differences in the metabolite profiles between the control group and IBS group significantly changed with the progression of IBS(days 0, 5, 10, and 17). A total of 14 differentially excreted metabolites were identified between the control and IBS groups, and phenylethylamine was a major metabolite induced by stress. In addition, phenylalanine metabolism was found to be the most relevant metabolic pathway. Between the IBS group and IBS + C. butyricum group, 10 differentially excreted metabolites were identified. Among these, pantothenate and coenzyme A(Co A) biosynthesis metabolites, as well as steroid hormone biosynthesis metabolites were identified as significantly relevant metabolic pathways.CONCLUSION The metabolic profile of IBS mice is significantly altered compared to control mice. Supplementation with C. butyricum to IBS mice may provide a considerable benefit by modulating host metabolism. 展开更多
关键词 IRRITABLE BOWEL syndrome METABOLITE gas chromatography/mass spectrometry CLOSTRIDIUM butyricum
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Rapid analysis of fifteen sulfonamide residues in pork and fish samples by automated on-line solid phase extraction coupled to liquid chromatography–tandem mass spectrometry 被引量:7
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作者 Junmei Ma Sufang Fan +3 位作者 Lei Sun Liangna He Yan Zhang Qiang Li 《Food Science and Human Wellness》 SCIE 2020年第4期363-369,共7页
The aim of this work was to develop an automated on-line solid phase extraction(SPE)with liquid chromatography-tandem mass spectrometry method for the detection of fifteen sulfonamides in pork and fish samples.Samples... The aim of this work was to develop an automated on-line solid phase extraction(SPE)with liquid chromatography-tandem mass spectrometry method for the detection of fifteen sulfonamides in pork and fish samples.Samples were extracted with 0.2%formic acid acetonitrile solution,purified by on-line SPE device with HLB column,then separated by XBridge C18 column,using 0.1%formic acid solution and acetonitrile as the mobile phase.Mass spectrometric data was acquired under multiple reaction monitoring(MRM)mode using positive ionization electrospray.Internal standard method was used in the quantification,good linear relationship was got in range of 0.1–100 ng/mL and correlation coefficient was higher than 0.9990.The limits of detection were in the range of 0.125–2.00g/kg and the limits of quantitation were in the range of 0.250–5.00g/kg.Recoveries of the method were in range of 78.3%–99.3%,relative standard deviation were lower than 10%.The method was simple,sensitivity,and could be used for routine supervision and analysis of fifteen sulfonamides in pork and fish. 展开更多
关键词 Liquid chromatographytandem mass spectrometry On-line solid phase extraction SULFONAMIDES Internal standard quantification
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Determination of urine catecholamines and metanephrines by reversed-phase liquid chromatography-tandem mass spectrometry 被引量:6
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作者 CHEUK Man-Yung LO Yun-Chuen POON Wing-Tat 《色谱》 CAS CSCD 北大核心 2017年第10期1042-1047,共6页
The measurement of urine catecholamine and metanephrine concentrations is important for biochemical screening and diagnosis of pheochromocytoma.The goal of this work was to develop a simple liquid chromatography-tande... The measurement of urine catecholamine and metanephrine concentrations is important for biochemical screening and diagnosis of pheochromocytoma.The goal of this work was to develop a simple liquid chromatography-tandem mass spectrometry(LC-MS/MS)method for determining catecholamines and metanephrines in urine to replace an existing liquid chromatographic method using electrochemical detection.Urine samples were prepared using Oasis weak-cation-exchange cartridges.The eluate was analyzed on an Agilent ZORBAX Eclipse Plus Phenyl-Hexyl column in 3 min.Adrenaline,noradrenaline,dopamine,metanephrine,normetanephrine,and their deuterated internal standards were monitored in positive electrospray ionization mode by multiple reaction monitoring(MRM).No evidence of ion suppression was observed.The assay was linear up to 5μmol/L for adrenaline,5μmol/L for noradrenaline,6.1μmol/L for dopamine,5.6μmol/L for metanephrine,and 34.6μmol/L for normetanephrine,with lower limits of quantification of 5,5,12,6 and 7nmol/L,respectively.The intra-day and inter-day precisions for all analytes ranged from 0.59%to 4.64%and1.98%to 4.80%,respectively.External quality assurance samples were assayed and showed excellent agreement with the target values.This simple method provides an improved assay for determining urine catecholamines and metanephrines. 展开更多
关键词 liquid chromatography-tandem mass spectrometry (LC-MS/MS) METANEPHRINES CATECHOLAMINES PHEOCHROMOCYTOMA URINE
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Extraction of essential oil from shaddock peel and analysis of its components by gas chromatography-mass spectrometry 被引量:2
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作者 周尽花 周春山 +1 位作者 蒋新宇 谢练武 《Journal of Central South University of Technology》 EI 2006年第1期44-48,共5页
Essential oil, with more than thirty kinds of compounds separated and identified by gas chromatography-mass spectrometry, was extracted from Shatian shaddock peel and Sweet shaddock peel by squeeze-steam distillation ... Essential oil, with more than thirty kinds of compounds separated and identified by gas chromatography-mass spectrometry, was extracted from Shatian shaddock peel and Sweet shaddock peel by squeeze-steam distillation and direct steam distillation method. Among their composition, the main components are terpene compounds, which account for 93.926% (mass fraction, the same below) and 85.843% of essential oils extracted from Shatian shaddock peel and Sweet shaddock peel, respectively. Although nootkatone is the major contributor of shaddock characteristic scent, and its contents are 1.069% and 1.749% of essential oils from Sweet shaddock peel and Shatian shaddock peel, respectively. The results show that squeeze-steam distillation gives higher yield and good quality of essential oil and the compositions of essential oils from two kinds of shaddock peels are different, but the main contributors of the shaddock scent are the same. 展开更多
关键词 essential oil Shatian shaddock Sweet shaddock gas chromatography - mass spectrometry nootkatone EXTRACTION
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A liquid chromatography with tandem mass spectrometry method for quantitating total and unbound ceritinib in patient plasma and brain tumor 被引量:1
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作者 Xun Bao Jianmei Wu +1 位作者 Nader Sanai Jing Li 《Journal of Pharmaceutical Analysis》 SCIE CAS CSCD 2018年第1期20-26,共7页
A rapid, sensitive, and robust reversed-phase liquid chromatography with tandem mass spectrometry method was developed and validated for the determination of total and unbound ceritinib, a secondgeneration ALK inhibit... A rapid, sensitive, and robust reversed-phase liquid chromatography with tandem mass spectrometry method was developed and validated for the determination of total and unbound ceritinib, a secondgeneration ALK inhibitor, in patient plasma and brain tumor tissue samples. Sample preparation involved simple protein precipitation with acetonitrile. Chromatographic separation was achieved on a Waters ACQUITY UPLC BEH C_(18) column using a 4-min gradient elution consisting of mobile phase A(0.1% formic acid in water) and mobile phase B(0.1% formic acid in acetonitrile), at a flow rate of 0.4 m L/min. Ceritinib and the internal standard([^(13)C_6]ceritinib) were monitored using multiple reaction monitoring mode under positive electrospray ionization. The lower limit of quantitation(LLOQ) was 1 n M of ceritinib in plasma. The calibration curve was linear over ceritinib concentration range of 1–2000 n M in plasma. The intra-and interday precision and accuracy were within the generally accepted criteria for bioanalytical method( o15%).The method was successfully applied to assess ceritinib brain tumor penetration, as assessed by the unbound drug brain concentration to unbound drug plasma concentration ratio, in patients with brain tumors. 展开更多
关键词 Ceritinib REVERSED-PHASE liquid chromatography with tandem mass spectrometry (LC–MS/MS) FRACTION unbound in PLASMA FRACTION unbound in BRAIN tissue BRAIN tumor penetration Unbound brain-to-plasma partition coefficient
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Determination of 8 Diuretics and Probenecid in Human Urine by Gas Chromatography-Mass Spectrometry: Confirmation Procedure 被引量:2
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作者 Olga Zaporozhets Iuna Tsyrulneva Mykola Ischenko 《American Journal of Analytical Chemistry》 2012年第4期320-327,共8页
A fast and sensitive method for determination of 8 diuretics (acetazolamide, bendroflumethiazide, bumetanide, chlorthalidone, furosemide, hydrochlorothiazide, metolazone, triamterene) and masking agent (probenecid) in... A fast and sensitive method for determination of 8 diuretics (acetazolamide, bendroflumethiazide, bumetanide, chlorthalidone, furosemide, hydrochlorothiazide, metolazone, triamterene) and masking agent (probenecid) in human urine using gas-chromatography with mass spectrometric detection is described. The extraction of the substances as function of the nature of organic solvent, mixing time and pH of aqueous phase was studied. The tandem mass spectrometry was used to increase selectivity of diuretics determination due to elimination of background interferences. Fragmentation reactions were studied for each compound and their collision energies were optimized to obtain the best selectivity. The results of method’s validation demonstrate its suitability in routine analysis for confirmation purposes. 展开更多
关键词 DIURETICS URINE gas chromatography tandem mass spectrometry CONFIRMATION
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Stereoselective separation and determination of quizalofopethyl in tobacco by ultra-performance convergence chromatography with tandem mass spectrometry 被引量:1
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作者 YANG Fei TANG Gangling +5 位作者 FAN Ziyan WANG Ying LIU Shanshan DENG Huimin BIAN Zhaoyang LI Zhonghao 《烟草科技》 EI CAS CSCD 北大核心 2018年第A01期38-46,共9页
The purpose of this study was to develop and validate a novel and sensitive method for simultaneous enantiomeric analysis of quizalofop-ethyl in tobacco using ultra-performance converge nee chromatography with tandem ... The purpose of this study was to develop and validate a novel and sensitive method for simultaneous enantiomeric analysis of quizalofop-ethyl in tobacco using ultra-performance converge nee chromatography with tandem mass spectrometry(UPC-MS/MS).Sample preparation prior to UPC^2-MS/MS analysis followed a QuEChERS(quick,easy,cheap,effective,rugged and safe)method.The UPC^2-MS/MS method used an Acquity UPC2 Trefoil CEL2 column with a mobile phase of CO2 and methanol.The injection volume was 2 μL and run-time was 6 min with the mobile phase running at 2.0 mL/min flow rate.Column temperature,auto back pressure regulator pressure(ABPR),and modifier solvent were optimized for separation efficiency.Under the optimal conditio ns,the recoveries for all the ena ntiomers were 81.3%-94.8% with relative standard deviations(RSD)less than 5.0% at 0.1,1.0 and 2.0 mg/kg levels,respectively.Good coefficients of determination(R^2≥0.993 7)were achieved for all the studied enantiomers in the tobacco over the concentration range of 10-250 ng/mL.The limits of detection(LODs)varied from 0.02 mg/kg to 0.04 mg/kg,and the limits of quantification(LOQs)were ≤ 0.13 mg/kg.The results confirm that the proposed method is green,convenient and reliable for the enantioselective determination of the enantiomers of quizalofop-ethyl in tobacco. 展开更多
关键词 QUIZALOFOP-ETHYL STEREOSELECTIVE separation HERBICIDE tandem mass spectrometry Ultraperformance CONVERGENCE chromatography
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Liquid chromatography tandem mass spectrometry method for the estimation of lamotrigine in human plasma:Application to a pharmacokinetic study 被引量:4
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作者 Santosh Ghatol Vatsal Vithlani +3 位作者 Sanjay Gurule Arshad Khuroo Tausif Monif Pankaj Partani 《Journal of Pharmaceutical Analysis》 SCIE CAS 2013年第2期75-83,共9页
A reliable,selective and sensitive liquid chromatography tandem mass spectrometry method was developed and validated for the quantification of lamotrigine in human plasma using lamotrigine13C3,d3 as an internal standa... A reliable,selective and sensitive liquid chromatography tandem mass spectrometry method was developed and validated for the quantification of lamotrigine in human plasma using lamotrigine13C3,d3 as an internal standard.Analyte and internal standard were extracted from human plasma by solid-phase extraction and detected in positive ion mode by tandem mass spectrometry with electrospray ionization(ESI) interface.Chromatographic separation was performed on a Chromolith s SpeedROD;RP-18e column(50-4.6 mm i.d.) using acetonitrile:570.1 mM ammonium formate solution(90:10,v/v) as the mobile phase at a flow rate of 0.500 mL/min.The calibration curves were linear over the range of 5.02-1226.47 ng/mL with the lower limit of quantitation validated at 5.02 ng/mL.The analytes were found stable in human plasma through three freeze(-20℃)-thaw(ice-cold water bath) cycles and under storage on bench-top in ice-cold water bath for at least 6.8 h,and also in the mobile phase at 10℃ for at least 57h.The method has shown good reproducibility,as the intra-and inter-day precisions were within 3.0%,while the accuracies were within 76.0% of nominal values.The validated LC-MS/MS method was applied for the evaluation of pharmacokinetic and bioequivalence parameters of lamotrigine after an oral administration of 50mg lamotrigine tablet to thirty-two healthy adult male volunteers. 展开更多
关键词 Lamotrigine Liquid chromatography/tandem mass spectrometry Solid phase extraction Pharmacokinetic study
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Determination of Sex Hormones in Antler Velvet by High Performance Liquid Chromatography Tandem Mass Spectrometry 被引量:1
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作者 LU Chun-mei WANG Ming-tai +4 位作者 MU Jun BAI Yu-ping DU Jian-shi ZHANG Han-qi WANG Jian-wei 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 2012年第2期191-194,共4页
Eighteen sex hormones in antler velvet were determined by high performance liquid chromatography tandem mass spectrometry.The solid phase extraction was applied to eliminating the matrix effect.The experimental condit... Eighteen sex hormones in antler velvet were determined by high performance liquid chromatography tandem mass spectrometry.The solid phase extraction was applied to eliminating the matrix effect.The experimental conditions were examined and optimized.Under the optimal conditions,the proposed method provides the good linearities and determination limits(0.2―1.0 μg/kg) of the analytes investigated.The recoveries ranging from 72.3% to 149.5% were obtained for the target analytes at two concentration levels.This method was applied to the determination of eighteen sex hormones in different kinds of antler velvet samples and the obtained results are satisfactory.The results indicate that the proposed method is suitable for the determination of sex hormones in antler velvet samples. 展开更多
关键词 Antler velvet Liquid chromatography tandem mass spectrometry Sex hormone Solid-phase extraction
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Uncertainty Evaluation of Determination of Microcystin MC-LR in Environmental Samples by Solid Phase Extraction-Ultra Performance Liquid Chromatography-Tandem Mass Spectrometry 被引量:1
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作者 Zhao Bin Zhang Min Zhang Fuhai 《Meteorological and Environmental Research》 CAS 2016年第6期54-57,共4页
To assess uncertainty of determination of MC-LR in environmental samples by solid phase extraction- ultra performance liquid chromatography- tandem mass spectrometry,the sources of the uncertainty were evaluated first... To assess uncertainty of determination of MC-LR in environmental samples by solid phase extraction- ultra performance liquid chromatography- tandem mass spectrometry,the sources of the uncertainty were evaluated firstly,and the expanded uncertainty was calculated finally.The results show that when MC-LR concentration in the water samples was 0.50 μg/L,the expanded uncertainty was 0.00628 μg/L(k=2). 展开更多
关键词 Uncertainty SOLID phase extraction Ultra performance liquid chromatography tandem mass spectrometry MICROCYSTIN MC-LR China
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Analyzing crude oils from the Junggar Basin(NW China) using comprehensive two-dimensional gas chromatography coupled with time-of-flight mass spectrometry(GC×GC-TOFMS) 被引量:1
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作者 Yuce Wang Wanyun Ma +2 位作者 Ni Zhou Jiangling Ren Jian Cao 《Acta Geochimica》 EI CAS CSCD 2017年第1期66-73,共8页
As a new technology of analyzing crude oils, comprehensive two-dimensional gas chromatography cou- pled with time-of-flight mass spectrometry (GCxGC- TOFMS) has received much research attention. Here we present a ca... As a new technology of analyzing crude oils, comprehensive two-dimensional gas chromatography cou- pled with time-of-flight mass spectrometry (GCxGC- TOFMS) has received much research attention. Here we present a case study in the Junggar Basin of NW China. Results show that the hydrocarbons, including saturates and aromatics, were all well-separated without large co- elution, which cannot be realized by conventional one-dimensional GC-MS. The GC×GC technique is especially effective for analyzing aromatics and low-to-middle- molecular-weight hydrocarbons, such as diamondoids. The geochemical characteristics of crude oils in the study area were investigated through geochemical parameters extracted by GC×GC-TOFMS, improving upon the understanding obtained by GC-MS. Thus, the work here represents a new successful application of GC×GC- TOFMS, showing its broad usefulness in petroleum geochemistry. 展开更多
关键词 Comprehensive two dimensional gas chromatography coupled with time of flight mass spectrometry (GCxGC TOFMS) Petroleum geochemistry Biomarkers Diamondoid Junggar Basin
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Fast and Sensitive Chiral Analysis of Amphetamines and Cathinones in Equine Urine and Plasma Using Liquid Chromatography Tandem Mass Spectrometry 被引量:1
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作者 Caroline C. Wang Petra Hartmann-Fischbach +5 位作者 Tim R. Krueger Alisha Lester Aaron Simonson Terry L. Wells Max O. Wolk Nick J. Hidlay 《American Journal of Analytical Chemistry》 2015年第13期995-1003,共9页
A simple, rapid, sensitive and reproducible method for enantiomer analysis of methamphetamine, amphetamine, cathinone and methcathinone was developed and validated. The compounds were extracted from equine plasma and ... A simple, rapid, sensitive and reproducible method for enantiomer analysis of methamphetamine, amphetamine, cathinone and methcathinone was developed and validated. The compounds were extracted from equine plasma and urine using a fast liquid-liquid extraction procedure. Only one milliliter plasma and one hundred microliter urine sample is needed for analysis. The extraction procedure had good recovery (>70%) and the matrix effect was negligible. Enantiomer differentiation and confirmation were achieved using liquid chromatography with chiral stationary phase and mass spectrometry detection. The method demonstrated excellent reproducibility with intra-day and inter-day precision of lower than 5%. The lower limits of detection for all of the compounds studied here were at low pg/mL level for both plasma and urine. This is the first report of the analysis of four chiral compounds in equine plasma and urine. Routine application was demonstrated for (S)- and (R)-enantiomer differentiation. 展开更多
关键词 AMPHETAMINES and CATHINONES EQUINE PLASMA and URINE Chiral Analysis Liquid chromatography tandem mass spectrometry
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Headspace Solid-Phase Micro-Extraction Gas Chromatography/Mass Spectrometry(HS-SPME-GC/MS)-Based Untargeted Metabolomics Analysis for Comparing the Volatile Components from 12 Panax Herbal Medicines 被引量:1
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作者 Simiao Wang Xiaohang Li +8 位作者 Meiting Jiang Xinlong Wu Yuying Zhao Meiyu Liu Xiaoyan Xu Huimin Wang Hongda Wang Heshui Yu Wenzhi Yang 《Phyton-International Journal of Experimental Botany》 SCIE 2022年第7期1353-1364,共12页
Quality control of ginseng currently is mainly based on ginsenoside analysis,but rarely focuses on the volatile organic components.In the current work,an untargeted metabolomics approach,by headspace solid-phase micro... Quality control of ginseng currently is mainly based on ginsenoside analysis,but rarely focuses on the volatile organic components.In the current work,an untargeted metabolomics approach,by headspace solid-phase micro-extraction gas chromatography/mass spectrometry(HS-SPME-GC/MS),was elaborated and further employed to holistically compare the compositional difference of the volatile components simultaneously from 12 Panax herbal medicines,which included P.ginseng(PG),P.quinquefolius(PQ),P.notoginseng(PN),red ginseng(PGR),P.ginseng leaf(PGL),P.quinquefolius leaf(PQL),P.notoginseng leaf(PNL),P.ginseng flower(PGF),P.quinquefolius flower(PQF),P.notoginseng flower(PNF),P.japonicus(PJ),and P.japonicus var.major(PJvm).Chromatographic separation was performed on an HP-5MS elastic quartz capillary column using helium as the carrier gas,enabling good resolution within 1 h.We were able to characterize totally 259 volatile compounds,including 82 terpenes(T),46 alcohols(Alc),29 ketones(K),25 aldehydes(Ald),21 esters(E),and the others.By analyzing 90 batches of ginseng samples based on the untargeted metabolomics workflows,236 differential ions were unveiled,and accordingly 36 differential volatile components were discovered.It is the first report that simultaneously compares the compositional difference of volatile components among 12 Panax herbal medicines,and useful information is provided for the quality control of ginseng aside from the well-known ginsenosides. 展开更多
关键词 Headspace solid-phase micro-extraction gas chromatography/mass spectrometry PANAX volatile component untargeted metabolomics
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Rapid Quantitative Determination of Isoprene Monomer in Living Taraxacum kok-saghyz by Ultra-High Performance Liquid Chromatography Tandem Mass Spectrometry 被引量:1
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作者 Xiang Tong Guo Tianyang +5 位作者 Zhang Xi Chen Yunhan Dong Yiyang Zhang Jichuan Ma Qiang Zhang Liqun 《China Petroleum Processing & Petrochemical Technology》 SCIE CAS 2020年第2期30-36,共7页
Taraxacum kok-saghyz(TKS)is rich in natural rubber(NR),a natural organic macromolecular compound composed of cis-1,4-polyisoprene,and may become the second NR-bearing plant for biochemical engineering development.In t... Taraxacum kok-saghyz(TKS)is rich in natural rubber(NR),a natural organic macromolecular compound composed of cis-1,4-polyisoprene,and may become the second NR-bearing plant for biochemical engineering development.In this paper,a rapid and quantitative ultra-high performance liquid chromatography tandem mass spectrometry(UHPLCMS/MS)method was established for determination of macromolecular biosynthesis substrate(dimethylallyl pyrophosphate,DMAPP)and initiator(farnesyl pyrophosphate,FPP)contained in TKS.A Kromasil C18 chromatographic column was used for separation,and the multi-reaction monitoring mode(MRM)of triple quadrupole mass spectrometry was used for detection.Quantification was performed by external calibration method.The results showed that the limit of detection(LOD)and the limit of quantitation(LOQ)of DMAPP were 2.42μg/L and 7.26μg/L,respectively,and the LOQ and the LOD of FPP were 1.02μg/L and 3.05μg/L,respectively.At a concentration of 1—1000μg/L,both analytes had good determination coefficients(>0.999)of calibration curve.The recoveries of DMAPP and FPP were between 99.0%and 117.1%.In real samples detection,the contents of DMAPP and FPP in TKS samples were between 23.32—82.77μg/L and 12.03—85.67μg/L,respectively.Thus,this approach is a reliable method to quantify DMAPP and FPP in TKS. 展开更多
关键词 QUANTITATION Taraxacum kok-saghyz(TKS) ISOPRENOIDS ultra-high performance liquid chromatography tandem mass spectrometry(UHPLC-MS/MS) natural rubber(NR)
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Trace-Level Analysis of Hexavalent Chromium in Lake Sediment Samples Using Ion Chromatography Tandem Mass Spectrometry 被引量:2
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作者 Stefanie Mädler Fengrong Sun +9 位作者 Cindy Tat Nadya Sudakova Peter Drouin Robert J. Tooley Eric J. Reiner Teresa A. Switzer Richard Dyer H. M. Skip Kingston Matt Pamuku Vasile I. Furdui 《Journal of Environmental Protection》 2016年第3期422-434,共13页
The analysis of hexavalent chromium, Cr(VI), in soil and sediment samples has been predominantly carried out in materials containing elevated levels. Reliable analysis of trace-level of Cr(VI) in sediment samples rema... The analysis of hexavalent chromium, Cr(VI), in soil and sediment samples has been predominantly carried out in materials containing elevated levels. Reliable analysis of trace-level of Cr(VI) in sediment samples remains challenging. Cr(VI) analyses with multipoint calibration and speciated isotope dilution (SID) adapted from U.S. EPA method 6800 were used to measure lower-level Cr(VI) on an ion chromatograph coupled with a tandem mass spectrometer (IC-MS/MS). Lake sediment samples were collected from various locations in Northern Ontario and Cr(VI) was extracted using both alkaline digestion and ethylene diaminetetraacetic acid (EDTA) extraction. Certified reference materials were extracted and analyzed by IC-MS/MS and UV-VIS detection. The SID-MS approach allowed for the quantification of Cr(VI) in samples with concentration levels below 0.5 μg.g-1 wet weight. 展开更多
关键词 Trace-Level Analysis Ion chromatography tandem mass spectrometry Chromium Speciation Speciated Isotope Dilution
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