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Science China Chemistry 2009年第12期52卷 2264-2268页

作者： LIU LiHong CHEN ZiLin Department of Pharmaceutical Analysis College of PharmacyWuhan UniversityWuhan 430072China

Peptidomics has emerged as a new discipline in recent years. Mass spectrometry (MS) is the most universal and efficient tool for structure identification of proteins and peptides. However,there is a limitation for the identification of peptides with the same amino acid composition but different se-quences because these peptides have identical mass spectra of molecular ions. This paper presents a high performance liquid chromatography-electrospray ionization-mass spectrometry (HPLC-ESI-MS) method for the separation of small molecular peptides with the same amino acid composition but dif-ferent sequences. Two tripeptides of Gly-Ser-Phe and Gly-Phe-Ser were used as a model sample. The separation behavior has been investigated and the separation conditions have been optimized. Under the optimum conditions,good repeatability was achieved. The developed method could provide a helpful reference for the separation of other peptides with the same amino acid composition but different sequences in the study of proteomics and peptidomics.

关键词： reversed-phase chromatography mass spectrometry peptides amino acid

Mass spectrometry analysis of melanoma related O-glycans in sera

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Science China Chemistry 2010年第4期53卷 807-811页

作者： BAI Chen1,4, WU Gang1 & ZHAO Liang2,3 1Department of Life Science, Fudan University, Shanghai 200433, China 2Department of Chemistry, Fudan University, Shanghai 200433, China 3Institutes of Biomedical Sciences, Fudan University, Shanghai 200433, China 4Department of Food Science, Shanghai Business School, Shanghai 200235, China Department of Life Science Fudan University Shanghai China Department of Food Science Shanghai Business School Shanghai China Department of Chemistry Fudan University Shanghai China Institutes of Biomedical Sciences Fudan University Shanghai China

Glycomics comparison was carried out by screening melanoma serum biomarkers between C57 mice with and without B16 implanted. O-glycans were released from 10 μL sera by β-elimination, purified by Graphitized Carbon Cartridge Solid Phase Extraction (GCC-SPE) and analyzed by MALDI-QIT-TOF-MS. MS raw data were acquired and exported by Launchpad software. MATLAB was then applied for further data analysis. 10 Glycans were considered to have stable changes after B16 implantation and 5 of them were under structural analysis via MS/MS.

关键词： mass spectrometry glycomics melanoma biomarkers

On-line trapping/capillary hydrophilic-interaction liquid chromatography/mass spectrometry for sensitive determination of RNA modifications from human blood

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Chinese Chemical Letters 2019年第3期30卷 553-557页

作者： Chubo Qi Hanpeng Jiang Jun Xiong Bifeng Yuan Yuqi Feng Key Laboratory of Analytical Chemistry for Biology and Medicine (Ministry of Education) Department of Chemistry Wuhan University Hubei Cancer Hospital Tongji Medical College Huazhong University of Science and Technology

RNA modification has recently been proposed to play important roles in biological regulation. The detection and quantification of RNA modifications generally are challenging tasks since most of the modifications exist in low abundance in vivo. Here we developed an on-line trapping/capillary hydrophilic-interaction liquid chromatography/electrospray ionization-mass spectrometry(on-line trapping/cHILIC/MS) method for sensitive and simultaneous quantification of RNA modifications of N^6-methyladenosine(m^6A) and 5-methylcytosine(5-mC) from human blood. The hydrophilic organic-silica hybrid monolith was prepared using sol-gel combined with "thiol-ene" click reaction for the separation of nucleosides. A poly(MAA-co-EGDMA) monolithic capillary was used as the on-line trapping column.With the developed on-line trapping/cHILIC/MS analytical platform, the detection limits of m^6A and 5-mC can reach to 0.06 fmol and 0.10 fmol. We then investigated the contents of m^6A and 5-mC in human blood RNA from healthy persons at the age of 6-14 and 60-68 years. Our results showed that both m^6A and 5-mC contents were significantly decreased in elder persons, suggesting the RNA modifications of m^6A and 5-mC are correlated to aging.

关键词： N^6-Methyladenosine 5-Methylcytosine Hydrophilic-interaction liquid chromatography Capillary monolithic column Mass spectrometry

Construction of on-line supercritical fluid extraction with reverse phase liquid chromatography–tandem mass spectrometry for the determination of capsaicin

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Chinese Chemical Letters 2019年第1期30卷 99-102页

作者： Naoki Hamada Yuki Hashi Satoshi Yamaki Yanli Guo Lin Zhang Haifang Li Jin-Ming Lin Beijing Key Laboratory of Microanalytical Methods and Instrumentation MOE Key Laboratory of Bioorganic Phosphorous Chemistry & Chemical BiologyDepartment of Chemistry Tsinghua University China MS Center Shimadzu (China) Co. Beijing Branch

A novel on-line system composed of supercritical fluid extraction(SFE), dilution line and reverse phase liquid chromatography/mass spectrometry(RPLC/MS) was constructed for on-line extraction and reverse phase separation of some fat-soluble components in foods. Three columns including a trap column,concentration column and analytical column were used for trapping the fat-soluble components, on-line enrichment and reverse phase separation, respectively. Capsaicinoids were on-line extracted by a CO_2 supercritical fluid, then concentrated and separated by using the C_(18) columns, finally detected by mass spectrometry(MS). Capsaicin eluted at 10.1 min and limit of detection(LOD, S/N=3) for the standard solution is 0.55pg. The linearity was calculated with a value of coefficient of determination(R^2)≥0.998 in the range of 1.1–8.5 ng. Concentrations of capsaicin in the green, yellow, and red bell peppers were determined to be 60.33 ng/g, 31.79 ng/g, 35.38ng/g, respectively.

关键词： Supercritical fluid extraction Liquid chromatography-mass spectrometry Column-switching system Capsaicin

Identification of two-dimensional electrophoresis-separated proteins in human hepatoma cell by electrospray ion trap mass spectrometry

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Chinese Science Bulletin 2000年第16期45卷 1509-1514页

作者： Rong Zeng Lirong Yu Xiaoxia Shao Qichang Xia Chinese Acad Sci Shanghai Inst Biochem Shanghai 200031 Peoples R China

As one of the most important analytical methods in proteome research, mass spectrometry was utilized to identify proteins separated by two-dimensional electrophoresis in the human hepatoma cell line BEL-7404. The protein spots were excised from the gel, followed by in-gel digestion, and the peptide mappings were analyzed by liquid chromatography electrospray ion trap mass spectrometer. Nine proteins were identified via database searching, according to the molecular weights and amino acid sequences of peptides, among which two proteins have not been identified in the other liver-cell database. The sequence coverage was 21% -72%. Furthermore, the relationship between the expressed proteins and the liver carcinoma was discussed.

关键词： ion trap mass spectrometry liver hepatoma cell proteome.

Study on fragmentation behavior of taxoids by tandem mass spectrometry

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Chinese Science Bulletin 2000年第8期45卷 688-698页

作者： Zeper Abliz Mitsuo Takayama Institute of Materia Medica Chinese Academy of Medical Sciences & Peking Union Medical CollegeBeiging 100050.ChinaFaculty of Pharmaceutical SciencesToho University2-2-1 MiyamaFunabashiChiba 274Japan

We have studied the fragmentation behavior of positive and negative ions of taxoi and 6/8/6 type taxoids, the influence of different substituents on fragmentation, and the correlativity between fragmentation patterns and structure by MS/MS technique with different ionization methods such as FAB-MS, ESI-MS, ete. We have also investigated in detail the fragmentation of various molecular-related ions, such as [M+H]+, [M+Na]+ and [M-H] ions, and the formation pathways of characteristic fragment ions. It has been found that there exists some competing reaction between the loss of C-13 side chain and decomposition by loss of acetic acid. In addition, by comparing CID spectra obtained with low- and high-energy collision, it is seen that CID-MS/MS with low-energy collision is more suitable for the study of the structural analysis of small molecules and drug metabolites. The experimental results demonstrate that MS/MS spectra can reflect more effectively the slight difference of structure between the related

关键词： taxol taxoids tandem mass spectrometry fragmentation behavior.

Studies on extracting solutions of endohedral rare-earth metallofullerenes by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry

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Science China Chemistry 1997年第6期40卷 590-599页

作者：孙大勇刘志强刘子阳郭兴华徐文国刘淑莹 The Key Laboratory of Applied Spectroscopy Changchun Institute of Applied ChemistryChinese Academy of SciencesChangchun 130022China

Thirteen extracting solutions of rare-earth metallofullerenes containing La,Ce,Pr,Nd Sm,Eu,Gd,Tb,Dy,Ho,Er,Tm and Yb respectively have been investigated by means of matrix-assisted laser desorpuon/ ionization time-of-flight mass spectrometry.The influences of the positive-ion/negative-ion mode,laser intensity,ma trix and mass discrimination to the analytical results are studied,based on which the optimal analytical conditions have been determined.The results show that the extracting solutions contain large quantities of rare-earth metallofullerenes besides empty fullerenes.On the basis of comparing their relative intensities,the different structure stabilities and solubilities of metallofullerenes with different rare-earth metals encapsulated into the fullerene cages,as well as some possible reasons to those differences,are discussed.

关键词： metallofullerenes fullerenes laser desorption/ionization time-of-flight mass spectrometry

Simultaneous determination of 15 pesticide residues in Chinese cabbage and cucumber by liquid chromatography-tandem mass spectrometry utilizing online turbulent flow chromatography

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Food Science and Human Wellness 2021年第1期10卷 78-86页

作者： Sufang Fan Junmei Ma Meirong Cao Juan Wang Leilei Zhang Yan Zhang Qiang Li Jia Chen Hebei Key Laboratory of Forensic Medicine College of Forensic MedicineHebei Medical UniversityShijiazhuang 050017China Hebei Food Safety Key Laboratory Hebei Food Inspection and Research Institute050227ShijiazhuangChina College of Food Science and Technology Hebei Agricultural University071001BaodingChina

In this experiment,a liquid chromatography tandem mass spectrometry method was built to determine 15 pesticide residues in Chinese cabbage and cucumber samples based on online turbulent flow chromatography purification.After modified quick,easy,cheap,effective,rugged,and safe(QuEChERS)extraction,extracts were directly injected to the TLX(TurboFlow Liquid Xcalibur)system and brought to TurboFlow™columns for on-line purification and then transferred to analytical column for further separation and analysis.TurboFlow™columns types,transfer flow rate,and transfer time were optimized.Limits of detection and limits of quantification of the method obtained for 15 pesticide residues were ranged between 0.2–1.0μg/kg and 0.5–2.0μg/kg in Chinese cabbage and cucumber samples.Recoveries of pesticide residues were in range of 75.3%–103.7%.Matrix effects for 15 pesticides were in range of 5.6%–106.6%.The developed method has been successfully used for the determination of 15 pesticide residues in real samples.

关键词： Pesticide residues Online turbulent flow chromatography Liquid chromatography-tandem mass spectrometry

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

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Food Science and Human Wellness 2020年第4期9卷 363-369页

作者： Junmei Ma Sufang Fan Lei Sun Liangna He Yan Zhang Qiang Li Hebei Key Laboratory of Forensic Medicine College of Forensic MedicineHebei Medical UniversityShijiazhuang 050017China Hebei Food Safety Key Laboratory Hebei Food Inspection and Research InstituteShijiazhuang 050227China

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.

关键词： Liquid chromatography–tandem mass spectrometry On-line solid phase extraction Sulfonamides Internal standard quantification

Genotoxic effects of low-dose exposure to pirimicarb studied with accelerator mass spectrometry

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Chinese Science Bulletin 1997年第19期42卷 1662-1664页

作者： Shi, JY Wang, HF Wu, XH Li, XS Liu, YF Li, K Lu, XY Wang, JJ Liu, KX BEIJING UNIV DEPT TECH PHYSBEIJING 100871PEOPLES R CHINA

SINCE 1990 a few papers presented by researchers at the Lawrence Livermore National Labora-tory(LLNL)have shown the great promise of accelerator mass spectrometry(AMS) inthe quantification of biological macromolecular adducts resulting from exposure to the exotictrace chemicals or toxins. For instance, they first successfully detected a carcinogen, 2-amino-3,8-dimethyl-imidazo (4, 5-f) quinoxaline (MeIQx), covalently bound to DNA by AMS.

关键词： pirimicarb DNA adduction accelerator mass spectrometry (AMS).