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Simultaneous determination of five anti-epilepsy drugs in human plasma using liquid chromatography-mass spectrometry

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Science China Chemistry 2010年第11期53卷 2373-2378页

作者： STEFANIE WeiBig Institute of Pharmaceutical Analysis College of PharmacyWuhan University

A new liquid chromatography-mass spectrometry method for the determination of carbamazepine,clonazepam,alprazolam,estazolam and phenytoin in human plasma has been developed by using diazepam as an internal standard.Chromatographic separation was performed on a Zorbax SB-C18 column(30 mm × 2.1 mm,3.5 ?m) with a mobile phase consisting of methanol and aqueous 25 mM ammonium acetate using gradient elution.A diethyl ether extraction method was used for the extraction of five anti-epilepsy drugs.The final extract was injected for analysis by LC-MS/MS.The method was validated within the concentration range of 50-5000 ng mL-1 for five anti-epilepsy drugs.The precision of the assay(RSD%) was less than 10% at all concentration levels within the tested range.The method recoveries for all samples were more than 90%.The results indicate that the method is specific,sensitive and accurate,and suitable to study the pharmacokinetics,to adjust the dosage for individual administration,and to monitor the drug-concentration and drug abuse of the five anti-epilepsy drugs.

关键词： liquid chromatography-mass spectrometry anti-epilepsy drugs plasma concentration

Performances of different efficiency calibration methods of high-purity-germanium gamma-ray spectrometry in an inter-comparison exercise

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Nuclear Science and Techniques 2019年第3期30卷 9-14页

作者： Bao-Lu Yang Qiang Zhou Jing Zhang Shuai-Mo Yao Ze-Shu Li Wen-Hong Li Fei Tuo Key Laboratory of Radiological Protection and Nuclear Emergency National Institute for Radiological ProtectionChinese Center for Disease Control and Prevention

This study reports the performances of efficiency calibrations for high-purity-germanium gamma-ray spectrometry using the source-, Laboratory Sourceless Object Calibration Software(LabSOCS)-and ANGLE-based methods in an inter-comparison exercise. Although the results of LabSOCS and ANGLE for ^(241)Am emitting lowenergy gamma rays were not very satisfactory, all of the three efficiency calibration methods passed acceptance criteria. The results confirmed the reliability of the calculation codes ANGLE and LabSOCS as alternative efficiency calibration methods in high-purity-germanium gamma spectrometry. This study is likely to promote the further application of the ANGLE and LabSOCS calculation codes in radioactivity measurements.

关键词： Efficiency calibration ANGLE Laboratory Sourceless Object Calibration Software (LabSOCS) Gamma-ray spectrometry

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

Metabolomic Fingerprint of the Model Ciliate, Tetrahymena thermophila Determined by Untargeted Profiling Using Gas Chromatography-Mass spectrometry

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Journal of Ocean University of China 2019年第3期18卷 654-662页

作者： XU Jing BO Tao SONG Weibo WANG Wei Institute of Evolution & Marine Biodiversity Ocean University of China Qingdao 266003 China Key Laboratory of Chemical Biology and Molecular Engineering of Ministry of Education Institute of Biotechnology Shanxi University Taiyuan 030006 China

The ciliate Tetrahymena is a valuable model organism in the studies of ecotoxicology. Changes in intracellular metabolism are caused by exogenous chemicals in the environment. Intracellular metabolite changes signify toxic effects and can be monitored by metabolomics analysis. In this work, a protocol for the GC-MS-based metabolomic analysis of Tetrahymena was established. Different extraction solvents showed divergent effects on the metabolomic analysis of Tetrahymena thermophila. The peak intensity of metabolites detected in the samples of extraction solvent Formula 1(F1) was the strongest and stable, while 61 metabolites were identified. Formula 1 showed an excellent extraction performance for carbohydrates. In the samples of extraction solvent Formula 2(F2), 66 metabolites were characterized, and fatty acid metabolites were extracted. Meanwhile, 57 and 58 metabolites were characterized in the extraction with Formula 3(F3) and Formula 4(F4), respectively. However, the peak intensity of the metabolites was low, and the metabolites were unstable. These results indicated that different extraction solvents substantially affected the detected coverage and peak intensity of intracellular metabolites. A total of 74 metabolites(19 amino acids, 11 organic acids, 2 inorganic acids, 11 fatty acids, 11 carbohydrates, 3 glycosides, 4 alcohols, 6 amines, and 7 other compounds) were identified in all experimental groups. Among these metabolites, amino acids, glycerol, myoinositol, and unsaturated fatty acids may become potential biomarkers of metabolite set enrichment analysis for detecting the ability of T. thermophila against environmental stresses.

关键词： Tetrahymena thermophila metabolomics ecotoxicology gas chromatography-mass spectrometry

Protein conformation in solution by three-dimensional fluorescence spectrometry

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Science China Chemistry 1996年第5期39卷 527-535页

作者：鄢远许金钩陈国珍 Department of Chemistry Nanchang University Nanchang 330047 China. Department of Chemistry Xiamen University Xiamen 361005 China

The conformations of bovine serum albumin (USA) and egg albumin (EA) in solution and their conformation changes under different conditions were studied by using three-dimensional fluorescence spectrometry (TDFS) such as three-dimensional fluorescence (TDF) spectra and three-dimensional fluorescence polarization (TDFP) spectra with tryptophan residues in protein molecules as an intrinsic fluorescent probe. The results show that the microenvironment of tryptophan residues of protein molecules in various solutions can be directly indicated and TDFS is an effective tool for studying protein conformation in solution. Meantime, some valuable results were obtained.

关键词： three-dimensional fluorescence spectrometry bovine serum albumin egg albumin protein conformation.

High-precision timing of the Quaternary standard samples with thermal ionization mass spectrometry (TIMS) U-series method

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Chinese Science Bulletin 1998年第4期43卷 333-336页

作者： Peng Zicheng Wang Zhaorong Sun Weidong Ma Zhibang Xia Ming Zhang Chenhui Chen Wenji Zhang Zhonglu An Zhisheng Univ Sci & Technol China Dept Earth & Space Sci Hefei 230026 Peoples R China Chinese Acad Sci Inst Geol Beijing 100029 Peoples R China State Seismol Bur Inst Geol Beijing 100029 Peoples R China State Key Lab Loess & Quaternary Geol Xian 710054 Peoples R China

Two national stalagmite standard （GBW04412, GBW04413） and one international coral standard （RKM4） have been determined by using thermal ionization mass spectrometry （TIMS） method. The values of （ 234 U/ 238 U） act , （ 230 Th/ 234 U） act and age are all consistent in error range with the standard values obtained by using α spectrometry.

关键词： thermal ionization mass spectrometry (TIMS) U_series method standard samples stalagmite and coral age determination.

Identification of secondary organic aerosols based on aerosol mass spectrometry

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中国科学：化学英文版 2010年第12期53卷 2593-2599页

作者： HUANG XiaoFeng 1,ZHAO QianBiao 1,2,HE LingYan 1,HU Min 2,BIAN QiJing 3,XUE Lian 1 & ZHANG YuanHang 2 1 Key Laboratory for Urban Habitat Environmental Science and Technology School of Environment and Energy,Peking University Shenzhen Graduate School,Shenzhen 518055,China 2 State Key Joint Laboratory of Environmental Simulation and Pollution Control College of Environmental Sciences and Engineering,Peking University,Beijing 100871,China 3 Division of Environment,Hong Kong University of Science & Technology,Hong Kong,China Key Laboratory for Urban Habitat Environmental Science and Technology School of Environment and Energy Peking University Shenzhen Graduate School Shenzhen China State Key Joint Laboratory of Environmental Simulation and Pollution Control College of Environmental Sciences and Engineering Peking University Beijing China Division of Environment Hong Kong University of Science & Technology Hong Kong China

Secondary organic aerosol (SOA) is one of the major components of aerosols in the atmosphere and has not been well understood so far.Due to the complex chemical composition of organic aerosols,the identification of SOA has been a hotspot and difficult issue in the field of aerosol study.This study attempts to quantitatively identify SOA in winter of Shenzhen based on positive matrix factorization (PMF) analysis.Major sources were resolved and SOA was identified subsequently according to the characteristic ion fragments measured by highly time-resolved aerosol mass spectrometer measurement.It showed that in the winter of Shenzhen the average SOA concentration was 9.41±6.33 g/m 3,accounting for 39.9±21.8% of the total organic mass.Compared with primary organic aerosol (POA),the SOA concentrations had no large variation,suggestive of characteristics of regional secondary pollutants.The ratio of SOA/BC had pronounced diurnal variation,similar to that of O x (O3+NO2),indicating SOA formation was significantly controlled by activity of photochemistry in the atmosphere.The most effective period for SOA formation was from 9 am～3 pm since the SOA/BC ratio increased by 122% during this period.This study provides a new technical method and a new idea for SOA investigation.

关键词： secondary organic aerosol aerosol mass spectrometry positive matrix factorization (PMF)

Profiling of Ubiquitination Modification Sites in Talin in Colorectal Carcinoma by Mass spectrometry

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Chemical Research in Chinese Universities 2019年第3期35卷 377-381页

作者： WANG Ke QIAO Lu LI Xiaoou LI Shimeng WANG Yimin XU Xuesong HE Chengyan FANG Ling China-Japan Union Hospital Jilin UniversityChangchun 130033P.R.China Tumor Hospital of Jilin Province Changchun 130012P.R.China

Talin protein was partially purified from human colorectal carcinoma tissues, which was subject to tryptic digestion. Immunoaffinity precipitation with specific antibodies that recognize diglycyl-lysine(Lys) remnants from tryptic digestion of ubiquitinated peptides was used to enrich ubiquitinated sites in talin. Mass spectrometry coupled with capillary reverse-phase high-performance liquid chromatography was used to analyze tlie enriched peptides. Specifically, four peptides containing diglycyl-Lys remnants from talin, namely, TAK(ub)VLVEDTK, QQQYK(ub) FLPSELRDEH, K(ub)STVLQQQYNR, and EGILK(ub)TAK can be determined using mass spectrometric data. This study provides an analytical method for further study in tlie relationship between ubiquitination modification of talin and its biological activity in colorectal cancer tissues with different pathological processes.

关键词： Talin Ubiquitination Colorectal carcinoma Mass spectrometry

Determination of ethanol content in ethanol-gasoline based on derivative absorption spectrometry and information fusion

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Optoelectronics Letters 2018年第6期14卷 442-446页

作者：周昆鹏白旭芳毕卫红 School of Physics and Electronic Information Inner Mongolia University for Nationalities The Key Laboratory for Special Fiber and Fiber Sensor of Hebei Province School of Information Science and Engineering Yanshan University

The ethanol content in ethanol-gasoline is respectively detected by the first-order derivative UV/vis absorption spectrum, the first-order derivative near infrared(NIR) absorption spectrum and the information fusion method. The backward interval partial least squares(BiPLS) algorithm is used as the feature extraction method, which is established by the partial least squares(PLS) regression model. Based on the information fusion theory, the low level data fusion(LLDF) and mid-level data fusion(MLDF) models are established by the first-order derivative UV/vis and NIR spectra. The analytical results are compared with the related textual references. Thereby, the single-spectral model based on the first-order derivative NIR absorption spectrum has the optimal results, where R_p^2 =0.999 1 and RMSEP=0.324 5, while the LLDF after vector normalization(LLDF-VN2) is the optimal multi-spectral fusion model, where R_p^2 =0.998 3 and RMSEP=0.498 2. The proposed method can be used to detect the ethanol content in ethanol-gasoline rapidly and provides a better choice for the component detection in mixed oils.

关键词： derivative absorption spectrometry information fusion ethanol-gasoline