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Sniffing with mass spectrometry

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Science Bulletin 2018年第20期63卷 1351-1357页

作者： Miao-Miao Chen Hai-Feng Su Ying Xie Li-Fang He Shui-Chao Lin Mei-Lin Zhang Cheng Wang Su-Yuan Xie Rong-Bin Huang Lan-Sun Zheng State Key Laboratory for Physical Chemistry of Solid Surfaces Collaborative Innovation Center of Chemistry for Energy Materials Department of Chemistry College of Chemistry and Chemical Engineering Xiamen University School of Information Science and Engineering Xiamen University

Gaseous compounds are usually on-line detectable on sensors. The limitations of conventional sensors are suffering from incapability for exactly identifying multiple components as well as incompatibility to possible toxicants in every odor sample. Herein, we discuss an inlet modification to the laboratory standard mass spectrometer, inspired by the sensitive olfactory systems of animals, for direct sniffing,established by connecting a mini pump to the nebulizer gas tubing. The modified mass spectrometry method—sniffing-mass spectrometry(sniffing-MS)—can acquire detailed fingerprint spectra of mixed odors and shows high tolerance to toxicants. Furthermore, the method has a low limit of detection in the order of parts per trillion and is a ‘sampling-free' technique for analyzing various gaseous compounds simultaneously, thus offering versatility for smelling daily commodities, tracking diffusion, and locating position of odors. Sniffing-MS can mimic or even surpass the olfaction of animals and is applicable for analyzing gaseous/volatile compounds, especially those polar compounds, in a simple manner depending on the intrinsic molecular mass-to-charge ratio.

关键词： Ambient mass spectrometry Volatile compounds Gas source locating On-line monitoring Olfaction

A liquid chromatography with tandem mass spectrometry method for quantitating total and unbound ceritinib in patient plasma and brain tumor

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Journal of Pharmaceutical Analysis 2018年第1期8卷 20-26页

作者： Xun Bao Jianmei Wu Nader Sanai Jing Li Karmanos Cancer Institute Wayne State University Barrow Neurological Institute St. Joseph's Hospital& Medical Center

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.

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

Optimization of Gas Chromatography-electron Ionization-tandem Mass spectrometry for Determining Toxic Non-ortho Polychlorinated Biphenyls in Breast Milk

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Biomedical and Environmental Sciences 2020年第1期33卷 58-61页

作者： Iva Simic Gordana Jovanovic Snjezana Herceg Romanic Darija Klincic Marijana Matek Saric Aleksandar Popovic Institute for Medical Research and Occupational Health Ksaverska cesta 2PO Box 29110001 ZagrebCroatia Institute of Physics Belgrade National Institute of the Republic of SerbiaUniversity of BelgradePregrevica 11811080 BelgradeSerbia Department of Health Studies University of ZadarSplitska 123000 ZadarCroatia Faculty of Chemistry University of BelgradeStudentski trg 12-1611000 BelgradeSerbia

One of the most commonly used non-invasive methods for assessing human exposure to pollution is the analysis of human milk.Human milk analyses help estimate the exposure of infants[1].This is why breast milk is receives scientific interest,and various methods for determining different pollutants from the environment are being developed[2,3].

关键词： Optimization Gas Chromatography-electron Ionization-tandem Mass spectrometry Determining Toxic Non-ortho Polychlorinated Biphenyls Breast Milk

Simultaneous determination of amino acids in different teas using supercritical fluid chromatography coupled with single quadrupole mass spectrometry

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Journal of Pharmaceutical Analysis 2019年第4期9卷 254-258页

作者： Yang Huang Tiejie Wang Marianne Fillet Jacques Crommen Zhengjin Jiang Institute of Pharmaceutical Analysis College of Pharmacy Jinan University Guangzhou 510632 China Shenzhen Institute for Drug Control Shenzhen China Department of Pharmaceutics State Key Laboratory of Natural Medicines China Pharmaceutical University Nanjing China Laboratory for the Analysis of Medicine Department of Pharmaceutical Sciences CIRM University of Liege CHU B36 B-4000 Liege Belgium

Tea is a widely consumed beverage and has many important physiological properties and potential health benefits. In this study, a novel method based on supercritical fluid chromatography coupled with mass spectrometry (SFC-MS) was developed to simultaneously determine 11 amino acids in different types of tea (green teas, Oolong tea, black tea and Pu-erh tea). The separation conditions for the analysis of the selected amino acids including the column type, temperature and backpressure as well as the type of additive, were carefully optimized. The best separation of the 11 amino acids was obtained by adding water (5%, v/v) and trifluoroacetic acid (0.4%, v/v) to the organic modifier (methanol). Finally, the developed SFC-MS method was fully validated and successfully applied to the determination of these amino acids in six different tea samples. Good linearity (r ≥ 0.993), precision (RSDs≤ 2.99%), accuracy (91.95%-107.09%) as well as good sample stability were observed. The limits of detection ranged from 1.42 to 14.69 ng/mL, while the limits of quantification were between 4.53 and 47.0 ng/mL. The results indicate that the contents of the 11 amino acids in the six different tea samples are greatly influenced by the degree of fermentation. The proposed SFC-MS method shows a great potential for further investigation of tea varieties.

关键词： Amino acids Teas Supercritical fluid chromatography with single quadrupole mass spectrometry (SFCMS)

Simultaneous analysis of allopurinol and oxypurinol using a validated liquid chromatography–tandem mass spectrometry method in human plasma

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Journal of Pharmaceutical Analysis 2017年第1期7卷 56-62页

作者： Dhiraj M. Rathod Keyur R. Patel Hiren N. Mistri Arvind G. Jangid Pranav S. Shrivastav Mallika Sanyal Department of Chemistry Kadi Sarva Vishwavidyalaya Gandhinagar Ahmedabad 382015 India Bioanalytical Research Department Accutest Research Lab Bodakdev Ahmedabad 380059 India Department of Chemistry School of Sciences Gujarat University Ahmedabad 380009 India Department of Chemistry St. Xavier's College Navrangpura Ahmedabad 380009 India

The present study describes a simple, reliable and reproducible liquid chromatography–tandem mass spectrometry method(LC–MS/MS) for the simultaneous determination of allopurinol and its active metabolite,oxypurinol in human plasma for a pharmacokinetic/bioequivalence study. After protein precipitation(PPT) of100 μL plasma sample with 1.0% formic acid in acetonitrile, the recovery of the analytes and allopurinol-d2 as an internal standard ranged from 85.36% to 91.20%. The analytes were separated on Hypersil Gold(150 mm×4.6 mm, 5 μm) column using 0.1% formic acid-acetonitrile(98:2, v/v) as the mobile phase.Quantification was done using electrospray ionization in the positive mode. The calibration concentration range was established from 60.0 to 6000 ng/m L for allopurinol and 80.0–8000 ng/m L for oxypurinol. Matrix effect in human plasma, expressed as IS-normalized matrix factors ranged from 1.003 to 1.030 for both the analytes. The developed method was found suitable for a clinical study with 300 mg allopurinol tablet formulation in healthy subjects.

关键词： Allopurinol Oxypurinol Liquid chromatography–tandem mass spectrometry Bioequivalence study

Effect of pediatric tuina on hypothalamic metabolites in young rabbits using liquid chromatography-mass spectrometry

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Journal of Traditional Chinese Medical Sciences 2022年第2期9卷 188-196页

作者： Zhifeng Liu Yi Jiao Tianyuan Yu Yingqi Zhang Di Liu Hourong Wang Yajing Xu Qian Guan Taotao Lv Jian Shu School of Acupuncture-Moxibustion and Tuina Beijing University of Chinese MedicineBeijing102488China Department of Acupuncture Dongfang Hospital Beijing University of Chinese MedicineBeijing100078China Shu Acupuncture Clinic FayettevilleNY13066USA

Objective: To investigate the changes in the hypothalamic metabolites of lipopolysaccharide(LPS) febrile young rabbits after the treatment with pediatric tuina.Methods: A total of 30 young rabbits were randomly assigned into three groups: the normal group, the model group, and the tuina group. Both the model group and the tuina group were injected intravenously with LPS. “Six antipyretic manipulations”(pushing Tianmen, pushing Kangong, kneading Taiyang,kneading Erhougaogu, clearing Tianheshui, and pushing Jizhu) were administered 1 h after the LPS injection in the tuina group. The rectal temperatures of the young rabbits were monitored during the experiment to explore the antipyretic effect. Three hours after the injection, the content of interleukin-1β(IL-1β), tumor necrosis factor(TNF)-a, and prostaglandin E;(PGE;) in the serum was detected. In addition, liquid chromatography-mass spectrometry(LC-MS) was used for the hypothalamus metabolomics.Results: Compared with the model group, the rectal temperature of the tuina group was decreased at 2 h and 3 h after the LPS injection(P =.04, P =.03, respectively), and the content of IL-1β, TNF-a, and PGE2was decreased(P =.03, P =.003, and P =.008, respectively). The metabolomics results showed that there were 23 potential biomarkers after the tuina intervention, enriching 27 pathways. Lipid metabolites,especially glycerophospholipids, were a majority of the altered metabolites. The primary metabolic pathways affected by tuina included the arachidonic acid metabolism, the GABAergic synapse, D-glutamine and D-glutamate metabolism, and the glutamatergic synapse.Conclusion: Pediatric tuina reduced the temperature of the febrile rabbits and downregulated the expression of IL-1β, TNF-a, and PGE2, and the antipyretic mechanism may be related to changes in metabolites and metabolic pathways in the hypothalamus.

关键词： Fever Pediatric tuina Metabolomics Liquid chromatography coupled with mass spectrometry Hypothalamus Interleukin-1b Tumor necrosis factor-a Prostaglandin E_(2)

Determination of thyreostats in bovine urine using ultra-high performance liquid chromatography-tandem mass spectrometry

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色谱 2017年第10期35卷 1048-1054页

作者： Lech RODZIEWICZ Jolanta MASLOWIECKA Anna SADOWSKA Halina CAR Laboratory of Chemical Examination of Foodstuffs Department of Veterinary Hygiene Department of Experimental Pharmacology Medical University of Bialystok

Five thyreostats(TSs),namely tapazole,thiouracil,methylthiouracil,propylthiouracil,and phenylthiouracil,were determined in bovine urine using ultra-high performance liquid chromatography-tandem mass spectrometry(UHPLC-MS/MS)in positive electrospray ionization mode.Extraction and clean-up were achieved using a ChemElut cartridge with tert-butyl methyl ether,without a derivatization step.Separation was achieved on an Acquity UPLC SS T3 column.The mobile phase was acetonitrile and water containing 0.2%(v/v)formic acid.The mass spectrometer was operated in multiple reaction monitoring mode.Urine samples were spiked with TS solution at levels corresponding to 5,10,15,and 20μg/L.The accuracy(internal standard corrected)ranged from 92%to 107%,with a repeatability precision(relative standard deviation,RSD)less than 15%for all five analytes.The RSDs within-laboratory reproducibility was less than 26%.The decision limits(CCα)and detection capabilities(CCβ)were obtained from a calibration curve and were in the ranges of 3.1-6.1μg/L and 4.0-7.4μg/L,respectively.The CCαand CCβvalues were below the recommended concentration,which was set at 10μg/L.The results show that the described method is suitable for the direct detection of TSs in bovine urine.This method can also be used to determine TSs in porcine urine.

关键词： ultra-high performance liquid chromatography-tandem mass spectrometry (UHPLC-MS/MS) thyreostats (TSs) urine

Unraveling enhanced membrane lipid biosynthesis in Chlamydomonas reinhardtii starchless mutant sta6 by using an electrospray ionization mass spectrometry-based lipidomics method

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Journal of Oceanology and Limnology 2020年第3期38卷 783-794页

作者： ZANG Zhengrong LI Yanhua HU Qiang HAN Danxiang Center for Microalgal Biotechnology and Biofuels Institute of HydrobiologyChinese Academy of SciencesWuhan 430072China Key Laboratory for Algal Biology Institute of HydrobiologyChinese Academy of SciencesWuhan 430072China University of Chinese Academy of Sciences Beijing 100049China State Key Laboratory of Freshwater Ecology and Biotechnology Institute of HydrobiologyChinese Academy of SciencesWuhan 430072China Laboratory for Marine Biology and Biotechnology Qingdao National Laboratory for Marine Science and TechnologyQingdao 266071China Beijing Key Laboratory of Algae Biomass Microalgae Biotechnology CenterSDIC Biotech Investment Co.Ltd.State Development&Investment Corp.Beijing 100142China

The unicellular green alga Chlamydomonas reinhardtii,a well-established model organism,has been widely used in dissecting glycerolipid metabolism in oxygenating photosynthetic organisms.In previous studies,it has been found that shunting carbon precursors from the starch synthesis pathway can lead to a 10-fold increase in TAG content as compared to the wild type,but it is unknown whether inactivation of AGPase may affect membrane lipids biosynthesis.The study aims to investigate global changes in lipid metabolism and homeostasis in the starchless mutant C.reinhardtii sta6.By utilizing an electrospray ionization/mass spectrometry(ESI/MS)-based lipidomics approach,a total of 105 membrane lipid molecules of C.reinhardtii were resolved,including 16 monogalactosyldiacylglycerol(MGDG),16 digalactosyldiacylglycerol(DGDG),11 phosphatidylglycerol(PG),6 sulfoquinovosyldiacylglycerol(SQDG),49 diacylglyceryl-N,N,N-trimethylhomoserine(DGTS),2 phosphatidylethanolamine(PE),and 5 phosphatidylinositol(PI)molecules.The quantitative results indicated that the membrane lipid profiles were similar between the two C.reinhardtii strains grown under both low-and high-light conditions,but the cellular contents of a great number of lipids were altered in sta6 due to the defect in starch biosynthesis.Under low-light conditions,sta6 accumulated more PI,MGDG,DGDG but less amounts of DGTS as compared to WT.Under high light,sta6 cells contained higher content membrane lipids than cc-124,except for PG,which is more or less similar in both strains.Our results demonstrate that the cellular membrane lipid homeostasis underwent profound changes in the starchless mutant,and thereby its physiological impact remains to be explored.

关键词： Chlamydomonas reinhardtii chloroplast lipidomes extraplastidic lipidomes electrospray ionization mass spectrometry

Determination of urine catecholamines and metanephrines by reversed-phase liquid chromatography-tandem mass spectrometry

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色谱 2017年第10期35卷 1042-1047页

作者： CHEUK Man-Yung LO Yun-Chuen POON Wing-Tat Department of Pathology Pamela Youde Nethersole Eastern Hospital

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.

关键词： liquid chromatography-tandem mass spectrometry (LC-MS/MS) metanephrines catecholamines pheochromocytoma urine