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Chinese Chemical Letters 2023年第3期34卷 245-249页

作者： Xinqi Chang Nina Wang Depeng Jiang Hong-Yuan Chen Dechen Jiang State Key Laboratory of Analytical Chemistry for Life Science School of Chemistry and Chemical EngineeringNanjing UniversityNanjing 210093China Department of Respiratory Medicine The Second Affiliated HospitalChongqing Medical UniversityChongqing 400010China

Angiotensin-converting enzyme 2(ACE2) is not only an enzyme but also a functional receptor on cell membrane for severe acute respiratory syndrome coronavirus 2(SARS-CoV-2). Here, the activity of ACE2 in single living cell is firstly determined using a nanokit coupled electrospray ionization mass spectrometry(nanokit-ESI-MS). Upon the insertion of a micro-capillary into the living h ACE2-CHO cell and the electrochemical sorting of the cytosol, the target ACE2 enzyme hydrolyses angiotensin II inside the capillary to generate angiotensin 1-7. After the electrospray of the mixture at the tip of the capillary, the product is differentiated from the substrate in molecular weight to achieve the detection of ACE2 activity in single cells. The further measurement illustrates that the inflammatory state of cells does not lead to the significant change of ACE2 catalytic activity, which elucidates the relationship between intracellular ACE2 activity and inflammation at single cell level. The established strategy will provide a specific analytical method for further studying the role of ACE2 in the process of virus infection, and extend the application of nanokit based single cell analysis.

关键词： Nanokit electrospray ionization mass spectrometry Single cell analysis The enzymatic activity ACE2

Effects of Temperature and Energy on Stability of Oligomeric Enzyme Probed on electrospray ionization mass spectrometry

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Chemical Research in Chinese Universities 2008年第6期24卷 771-777页

作者： LI Zhi-li Institute of Basic Medical Sciences Chinese Academy of Medical Sciences ＆ Peking Union Medical College Beijing 100005 P. R. China

Escherichia coli 3-Deoxy-D-manno-octulosonate 8-phosphate（KDO8P） synthase catalyzed the condensation reaction between D-arabinose 5-phosphate（A5P） and phosphoenolpyruvate（PEP） to form KDO8P and inorganic phosphate（Pi）. The noncovalent tetrameric association ofKDO8P synthase was observed and dissociated in gas phase by means of electrospray ionization mass spectrometry under the very ＂soft＂ conditions. The results indicate that PEP-bound enzyme generated abundant tetrameric species as well as monomeric species at the ＂soft＂ conditions, whereas, the unbound enzyme favored the formation of a dimeric species. The mass spectra of the mixture of the enzyme with one of substrates, PEP, and A5P or one of products, KDO8P and Pi show that the complex of the unbound enzyme with PEP or Pi was prone to the formation of a monomeric species, whereas, that of the unbound enzyme with A5P or KDO8P was similar to the unbound enzyme. The intensity of the dimeric species increased with the increase of temperature at a collision voltage of 10 V. Taken together, the results presented here suggest that mass spectrometry will be a powerful tool to explore subtile conformational changes and/or subunit-subunit interactions of multiprotein assembly induced by ligand-binding and/or the changes of environmental conditions.

关键词： electrospray ionization mass spectrometry 3-Deoxy-D-manno-octulosonate 8-phosphate(KDO8P) syn- thase Oligomeric stability

Simultaneous determination of quetiapine and three metabolites in human plasma by high-performance liquid chromatography-electrospray ionization mass spectrometry

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Acta Pharmacologica Sinica 2004年第1期 112-116页

作者： Kun-yan LI, Ze-neng CHENG, Xin LI, Xue-lian BAI, Bi-kui ZHANG, Feng WANG, Huan-de LIClinical Pharmaceutical Research Institute, Xiangya Second Hospital, Central South University, Changsha 410011, China

AIM: To develop a high performance liquid chromatography-electrospray mass spectrometry (HPLC-MS/ESI) method for simultaneous determination of quetiapine and its sulfoxide-, 7-hydroxy-, 7-hydroxy-N-dealkyl-metabo-lites in human plasma. METHODS: The HPLC separation of the compounds was performed on a Kromasil C18, (5 urn, 4.6 mm×150 mm) column, using water (formic acid: 1.70 mmol/L, ammonium acetate: 5.8 mmol/L)-acetoni trile (65:35) as mobile phase, with a flow-rate of 0.95 mL/min. The compounds were ionized in the electrospray ionization (ESI) ion source of the mass spectrometer and detected in the selected ion recording (SIR) mode. The samples were extracted using solid-phase extraction columns. RESULTS: The calibration curves were linear in the ranges of 10-2000 μg/L for quetiapine, 1-200 μg/L for its metabolites, respectively. The average extraction recoveries for all the four samples were above 85 %.

关键词： quetiapine high pressure liquid chromatography electrospray ionization mass spectrometry metabolism

Identification of cadmium containing metabolites in HepG2 cells after treatment with cadmium-selenium quantum dots

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Chinese Chemical Letters 2023年第1期34卷 564-568页

作者： Beibei Chen Lu Peng Man He Chuan Wang Bin Hu Department of Chemistry Wuhan UniversityWuhan 430072China

The transformation of quantum dots(QDs)by organisms has attracted broad attention but remains *** of the metabolites helps to reveal the transformation pathway of *** containingmetallothionein(MT)are the main species formed by Cd released from CdSe QDs in HepG2 cells,while speciation analysis of Cd containing MTs remains a challenge because MTs has several subisoforms and can bind with several ***,we built a hyphenated platform for speciation analysis of QDs in HepG2 cells after treatment with CdSe/ZnS *** Cd-containing MTs were separated in reversed phase high performance liquid chromatography(RP-HPLC)and subsequently online detected by inductively coupled plasma mass spectrometry(ICP-MS)and electrospray ionization quadrupole time-of-flight mass spectrometry(ESI-Q-TOF-MS)*** groups of Cd-containing metabolites were found by detecting Cd in *** structures were identified in ESI-Q-TOF-MS and further confirmed with standards of four subisoforms of MT,including N-terminal acetylation MT2a,N-terminal acetylation MT1e,N-terminal acetylation MT1g and *** group of them contains various stoichiometry of Cd/*** metabolites of QDs remain same while the concentrations of each metabolite and its stoichiometry of Cd/Zn vary for different incubation concentration/*** work provides a new parallel hyphenation technique of HPLC-ICP-MS/ESI-MS with high separation resolution and powerful detection ability,and the obtained results provide detailed metabolism information of QDs in HepG2 cells after treatment of CdSe/ZnS QDs,contributing to deep exploration of the functional mechanisms of QDs in organisms.

关键词： CdSe/ZnS quantum dots Cd speciation Metallothionein Cells High performance liquid chromatography Inductively coupled plasma mass spectrometry electrospray ionization mass spectrometry

Characterization of Acute Renal Allograft Rejection by Human Serum Proteomic Analysis

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Journal of Huazhong University of Science and Technology(Medical Sciences) 2009年第5期29卷 585-591页

作者：高英吴轲徐逸周鸿敏何文涛张维娜蔡兰军林星光方泽民雒真龙郭晖陈忠华 Institute of Organ Transplantation Tongji HospitalTongji Medical CollegeHuazhong University of Science and TechnologyKey Laboratory of Organ TransplantationMinistry of EducationMinistry of Health

To identify acute renal allograft rejection biomarkers in human serum, two-dimensional differential in-gel electrophoresis （2-D DIGE） and reversed phase high-performance liquid chromatography （RP-HPLC） followed by electrospray ionization mass spectrometry （ESI-MS） were used. Serum samples from renal allograft patients and normal volunteers were divided into three groups： acute rejec- tion （AR）, stable renal function （SRF） and normal volunteer （N）. Serum samples were firstly processed using Multiple Affinity Removal Column to selectively remove the highest abundance proteins. Differentially expressed proteins were analyzed using 2-D DIGE. These differential protein spots were excised, digested by trypsin, and identified by RP-HPLC-ESI/MS. Twenty-two differentially expressed proteins were identified in serum from AR group. These proteins included complement C9 precursor, apolipoprotein A-IV precursor, vitamin D-binding protein precursor, beta-2-glycoprotein 1 precursor, etc. Vitamin D-binding protein, one of these proteins, was confirmed by ELISA in the independent set of serum samples. In conclusion, the differentially expressed proteins as serum biomarker candidates may provide the basis of acute rejection noninvasive diagnosis. Confirmed vitamin D-binding protein may be one of serum biomarkers of acute rejection. Furthermore, it may provide great insights into understanding the mechanisms and potential treatment strategy of acute rejection.

关键词： acute rejection two-dimensional differential in-gel electrophoresis reversed phase high-performance liquid chromatography electrospray ionization mass spectrometry ELISA serum

Study on the Structural Effect of Maltoligosaccharides on Cytochrome c Complexes Stabilities by Native mass spectrometry

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Natural Products and Bioprospecting 2018年第1期8卷 57-61页

作者： Quan Chi Ying-Zhi Liu Xian Wang Key Laboratory of Analytical Chemistry of the State Ethnic Affairs Commission College of Chemistry and Materials ScienceSouth-Central University for NationalitiesWuhanHubei 430074People’s Republic of China

Noncovalent interactions between ligands and targeting proteins are essential for understanding molecular mechanisms of *** this work,we investigated the interaction of Cytochrome c(Cyt c)with maltoligosaccharides,namely maltose(Mal Ⅱ),maltotriose(Mal Ⅲ),maltotetraose(Mal Ⅳ),maltopentaose(Mal Ⅴ),maltohexaose(Mal Ⅵ)and maltoheptaose(Mal Ⅶ).Using electrospray ionization mass spetrometry(ESI-MS)assay,the 1:1 and 1:2 complexes formed by Cyt c with maltoligosaccharide ligand were *** corresponding association constants were calculated according to the deconvoluted *** order of the relative binding affinities of the selected oligosaccharides with Cyt c were as MalⅢ>MalⅣ>MalⅡ>MalⅤ>MalⅥ>MalⅦ.The results indicated that the stability of noncovalent protein complexes was intimately correlated to the molecular structure of bound *** relevant functional groups that could form H-bonds,electrostatic or hydrophobic forces with protein’s amino residues played an important role for the stability of protein *** addition,the steric structure of ligand was also critical for an appropriate interaction with the binding pocket of proteins.

关键词： electrospray ionization mass spectrometry Maltoligosaccharides Cytochrome c complexes Structure-binding relationship

双链DNA与生物碱类化合物非共价作用的电喷雾质谱研究

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双链DNA与生物碱类化合物非共价作用的电喷雾质谱研究

中国有机质谱学第十三届全国学术大会

作者：宋凤瑞刘志强刘淑莹中国科学院长春应用化学研究所新药研究实验室长春质谱中心

据文献报道,临床上使用的很多抗癌药物都是以DNA为主要的作用靶点,通过与癌细胞的 DNA发生相互作用破坏其结构,进而影响基因调控与表达的功能,表现出抗癌活性。而随着中药抗恶性肿瘤研究的不断深入,其作用机理及活性筛选的方法学研究也... 详细信息

据文献报道,临床上使用的很多抗癌药物都是以DNA为主要的作用靶点,通过与癌细胞的 DNA发生相互作用破坏其结构,进而影响基因调控与表达的功能,表现出抗癌活性。而随着中药抗恶性肿瘤研究的不断深入,其作用机理及活性筛选的方法学研究也倍受关注。本文利用电喷雾质谱技术,以双链DNA为靶分子,通过对其与小檗碱类生物碱成分非共价复合作用的研究,探讨生物质谱方法作为药物筛选方法的可行性。

关键词： Oligodeoxynucleotide Alkaloid Non-covalent complex electrospray ionization mass spectrometry

纺锤菌素与双链及三链核酸相互作用的电喷雾质谱研究

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纺锤菌素与双链及三链核酸相互作用的电喷雾质谱研究

中国有机质谱学第十四届全国学术大会

作者：万翠红刘志强刘淑莹中国科学院长春应用化学研究所长春质谱中心

纺锤菌素作为一种特异的小沟结合剂,虽然太毒不能用于临床,但被广泛用于生物物理学研究,以阐明小沟结合药物的特异性原理。关于它与双链核酸的相互作用研究已经很深入了,但是它与三链核酸相互作用的研究还很有限。本研究利用电喷雾质谱... 详细信息

纺锤菌素作为一种特异的小沟结合剂,虽然太毒不能用于临床,但被广泛用于生物物理学研究,以阐明小沟结合药物的特异性原理。关于它与双链核酸的相互作用研究已经很深入了,但是它与三链核酸相互作用的研究还很有限。本研究利用电喷雾质谱研究纺锤菌素对双链和三链核酸的结构选择性,以及其碱基序列选择性。

关键词： netropsin triplex DNA duplex DNA electrospray ionization mass spectrometry structure selectivity sequence selectivity

Rapid quantification of iridoid glycosides analogues in the formulated Chinese medicine Longdan Xiegan Decoction using high-performance liquid chromatography coulpled with mass spectromentry(LC/MS/MS)

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Rapid quantification of iridoid glycosides analogues in the ...

中华中医药学会中药分析分会第三届学术交流会

作者： Li Yang~a,Yun Wang~a,Longxing Wang~b,Hongbin Xiao~b,Zhengtao Wang~(a*),Zhibi Hu~a a Key Laboratory of Standardization of Chinese Medicines of Ministry of Education,Shanghai University of Traditional Chinese Medicine,1200 Cailun Road,Zhangjiang Hi-tech Park, Shanghai 201203,China b Dalian Institute of Chemical Physics,Chinese Academy of Sciences,457 Zhongshan Road, Dalian 116023,China

Longdan Xiegan Decoction(LXD) is a formulated preparation composed of ten ingredient herbs,with iridoids as one group of the main bioactive *** this study,a rapid,simple and reliable method of simultaneous determination of four iridoid glycosides in LXD using high-performance liquid chromatography(HPLC) coupled with electrospray ionization mass spectrometry(MS) was first developed and validatedThe four iridoid glycosides references were isolated from LXD extract and purified using a preparative HPLC chromatography(the purities of all four analytes≥98%for assay purpose).The sample preparation for quantification comprised of a simple ultrasonic extraction and the separation of four structurally similar iridoid glycosides was effected by HPLC(CAPCELL PAK C MGⅡcolumn,3μm,100 mm×2.0 mm) using an elution system of 10%methanol Satisfactory chromatographic separation of these analytes was obtained in less than three minutes and the concentrations of four iridoid glycosides in different batches of LXD and ingredient herbs were simultaneously determined by HPLC-MS/MS using a multiple reaction monitoring(MRM) *** method was validated with respect to the overall intra- and inter-day variation(RSD less than 8%) and the limits of quantification for the four iridoid glycosides were 35,20,37 and 33 ng/mL,respectively. The main result are shown in Figures 1-3 and tables 1-3.

关键词： iridoid glycosides Longdan Xiegan Decoction Gentianae Radix Gardeniae Fructus high performance liquid chromatography electrospray ionization mass spectrometry multiple reaction monitoring(MRM)

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皂甙化合物的氯加合负离子质谱研究

皂甙化合物的氯加合负离子质谱研究

中国质谱学会第七届会员代表大会暨学术报告会

作者：熊蕾赵镇文李小妹胡伟华辛斌熊少祥中国科学院化学研究所北京质谱中心长江生命科技有限公司

在质谱样品离子化过程中,由实验体系中存在的H、Na、K等离子与样品分子结合而形成加合物离子,是一个普遍的现象。该现象也成为应用快原子轰击(FAB)、电喷雾(ESI)、基质辅助激光解吸电离(MALDI)等进行质谱分析时使样品得以离子化的基础... 详细信息

在质谱样品离子化过程中,由实验体系中存在的H、Na、K等离子与样品分子结合而形成加合物离子,是一个普遍的现象。该现象也成为应用快原子轰击(FAB)、电喷雾(ESI)、基质辅助激光解吸电离(MALDI)等进行质谱分析时使样品得以离子化的基础。因此,在样品制备过程中,人为地加入某些碱金属或过渡金属的化合物作为离子化试剂,已成为提高信噪比,增强目标峰;抑制杂质峰,使样品得以检测的重要步骤。但是,目前人们利用和研究较多的是带正电荷的加合物离子,带负电荷的加合物离子却很少。本实验室在用电喷雾质谱负离子检测皂甙化合物时,发现Cl等卤素负离子可以非常容易地与样品结合,形成带负电荷的[M+X]加合物离子。本工作拟对此进行较为详细的研究。

关键词： chlorin adduct ion saponin electrospray ionization mass spectrometry