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Stepped-up development of accelerator mass spectrometry method for the detection of ^(60)Fe with the HI-13 tandem accelerator 被引量:1
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作者 Yang Zhang Sheng-Quan Yan +36 位作者 Ming He Qing-Zhang Zhao Wen-Hui Zhang Chao-Xin Kan Jian-Ming Zhou Kang-Ning Li Xiao-Fei Wang Jian-Cheng Liu Zhao-Hua Peng Zhuo Liang Ai-Ling Li Jian Zheng Qi-Wen Fan Yun-Ju Li You-Bao Wang Zhi-Hong Li Yang-Ping Shen Ding Nan Wei Nan Yu-Qiang Zhang Jia-Ying-Hao Li Jun-Wen Tian Jiang-Lin Hou Chang-Xin Guo Zhi-Cheng Zhang Ming-Hao Zhu Yu-Wen Chen Yu-Chen Jiang Tao Tian Jin-Long Ma Yi-Hui Liu Jing-Yu Dong Run-Long Liu Mei-Yue-Nan Ma Yong-Shou Chen Wei-Ping Liu Bing Guo 《Nuclear Science and Techniques》 SCIE EI CAS CSCD 2024年第4期136-143,共8页
The Moon provides a unique environment for investigating nearby astrophysical events such as supernovae.Lunar samples retain valuable information from these events,via detectable long-lived“fingerprint”radionuclides... The Moon provides a unique environment for investigating nearby astrophysical events such as supernovae.Lunar samples retain valuable information from these events,via detectable long-lived“fingerprint”radionuclides such as^(60)Fe.In this work,we stepped up the development of an accelerator mass spectrometry(AMS)method for detecting^(60)Fe using the HI-13tandem accelerator at the China Institute of Atomic Energy(CIAE).Since interferences could not be sufficiently removed solely with the existing magnetic systems of the tandem accelerator and the following Q3D magnetic spectrograph,a Wien filter with a maximum voltage of±60 kV and a maximum magnetic field of 0.3 T was installed after the accelerator magnetic systems to lower the detection background for the low abundance nuclide^(60)Fe.A 1μm thick Si_(3)N_(4) foil was installed in front of the Q3D as an energy degrader.For particle detection,a multi-anode gas ionization chamber was mounted at the center of the focal plane of the spectrograph.Finally,an^(60)Fe sample with an abundance of 1.125×10^(-10)was used to test the new AMS system.These results indicate that^(60)Fe can be clearly distinguished from the isobar^(60)Ni.The sensitivity was assessed to be better than 4.3×10^(-14)based on blank sample measurements lasting 5.8 h,and the sensitivity could,in principle,be expected to be approximately 2.5×10^(-15)when the data were accumulated for 100 h,which is feasible for future lunar sample measurements because the main contaminants were sufficiently separated. 展开更多
关键词 Accelerator mass spectrometry Wien filter Isobar separation SUPERNOVAE Chang'e-5 lunar samples
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Improved isochronous mass spectrometry with tune measurement
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作者 Han-Yu Deng Yuan-Ming Xing +5 位作者 Xu Zhou Yu-Hu Zhang Xin-Liang Yan Jin-Yang Shi Ting Liao Meng Wang 《Nuclear Science and Techniques》 SCIE EI CAS CSCD 2024年第11期174-181,共8页
In conventional isochronous mass spectrometry(IMS)performed on a storage ring,the precision of mass measurements for short-lived nuclei depends on the accurate determination of the revolution times(T)of stored ions.Ho... In conventional isochronous mass spectrometry(IMS)performed on a storage ring,the precision of mass measurements for short-lived nuclei depends on the accurate determination of the revolution times(T)of stored ions.However,the resolution of T inevitably deteriorates due to the magnetic rigidity spread of the ions,limiting the mass-resolving power.In this study,we used the betatron tunes Q(the number of betatron oscillations per revolution)of the ions and established a correlation between T and Q.From this correlation,T was transformed to correspond to a fixed Q with higher resolution.Using these transformed T values,the masses of ^(63)Ge,^(65)As,^(67)Se,and ^(71)Kr agreed well with the mass values measured using the newly developed IMS(Bρ-IMS).We also studied the systematics of Coulomb displacement energies(CDEs)and found that anomalous staggering in CDEs was eliminated using new mass values.This method of T transformation is highly effective for conventional IMS equipped with a single time-of-flight detector. 展开更多
关键词 Isochronous mass spectrometry Storage ring TUNE Natural chromaticity Nuclear mass measurement
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Mass Spectrometry-based Deep Coverage Proteome:Evaluation of Cellular Protein Extraction Methods
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作者 XU Xia QIN Weida +3 位作者 LI Ruomeng WANG Qianqian LIU Ning LI Gongyu 《高等学校化学学报》 SCIE EI CAS CSCD 北大核心 2024年第11期98-107,共10页
The current study comprehensively evaluates four different protein extraction methods based on urea,sodium dodecyl sulfate(SDS),anionic surfactants(BT),and total RNA extractor(Trizol),aiming to optimize the sample pre... The current study comprehensively evaluates four different protein extraction methods based on urea,sodium dodecyl sulfate(SDS),anionic surfactants(BT),and total RNA extractor(Trizol),aiming to optimize the sample preparation workflow for mass spectrometry-based proteomics.Using HeLa cells as an example,we found that the method employing the mass spectrometry-compatible surfactant BT reagent significantly reduces the total time consumed for protein extraction and minimizes protein losses during the sample preparation process.Further integrating the four protein extraction methods,we identified over 7000 proteins from HeLa cells without relying on pre-fractionation techniques,and 2990 of them were quantified using label-free quantification.It is worth noting that the BT and SDS methods demonstrate higher efficiency in extracting membrane proteins,while the Urea and Trizol methods are more effective in extracting proteins from nuclear and cytoplasmic fractions.In summary,this study provides a novel solution for deep proteome coverage,particularly in the context of cellular protein extraction,by integrating mass spectrometry-compatible surfactants with traditional extraction methods to effectively enhance protein identification numbers. 展开更多
关键词 SURFACTANT Protein extraction PROTEOMICS mass spectrometry
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Bacterial Protein Profiling——Comparison of Three Mass Spectrometry Methodologies
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作者 JIANG Yan CHEN Yanlin +4 位作者 SONG Gaoyu CHEN Yanyan BAI Jing ZHU Yingdi LI Juan 《高等学校化学学报》 SCIE EI CAS CSCD 北大核心 2024年第11期158-173,共16页
Profiling the protein composition of bacteria is essential for understanding their biology,physiology and interaction with environment.Mass spectrometry has become a pivotal tool for protein analysis,facilitating the ... Profiling the protein composition of bacteria is essential for understanding their biology,physiology and interaction with environment.Mass spectrometry has become a pivotal tool for protein analysis,facilitating the examination of expression levels,molecular masses and structural modifications.In this study,we compared the performance of three widely-used mass spectrometry methods,i.e.,matrix-assisted laser desorption/ionization(MALDI)protein fingerprinting,top-down proteomics and bottom-up proteomics,in the profiling of bacterial protein composition.It was revealed that bottom-up proteomics provided the highest protein coverage and exhibited the greatest protein profile overlap between bacterial species.In contrast,MALDI protein fingerprinting demonstrated superior detection reproducibility and effectiveness in distinguishing between bacterial species.Although top-down proteomics identified fewer proteins than bottom-up approach,it complemented MALDI fingerprinting in the discovery of bacterial protein markers,both favoring abundant,stable,and hydrophilic bacterial ribosomal proteins.This study represents the most systematic and comprehensive comparison of mass spectrometry-based protein profiling methodologies to date.It provides valuable guidelines for the selection of appropriate profiling strategies for specific analytical purposes.This will facilitate studies across various fields,including infection diagnosis,antimicrobial resistance detection and pharmaceutical target discovery. 展开更多
关键词 BACTERIA Protein profiling mass spectrometry
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Determination of Ten Kinds of Alpha-2 Agonists Residues in Animal Derived Food by UHPLC-Triple Quadrupole/Composite Linear Ion Trap Mass Spectrometry
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作者 Fang LI Xuemei LI +3 位作者 Xiangang LI Sining LIU Sha LIU Ying WANG 《Plant Diseases and Pests》 2024年第1期28-32,共5页
[Objectives]The paper was to establish an ultra high performance liquid chromatography-quadrupole/linear ion trap complex mass spectrometry for the determination of 10 kinds ofα2-receptor agonists in animal derived f... [Objectives]The paper was to establish an ultra high performance liquid chromatography-quadrupole/linear ion trap complex mass spectrometry for the determination of 10 kinds ofα2-receptor agonists in animal derived food.[Methods]The samples were extracted with sodium carbonate buffer solution and ethyl acetate,and analyzed by mass spectrometry after solid phase extraction and high performance liquid chromatography separation.[Results]Ten kinds ofα2-receptor agonists showed a good linear relationship in the range of 1-100μg/mL,with the average recovery of over 69%and the relative standard deviation less than 8.32%.The detection limit of 10 kinds of α_(2)-receptor agonists was up to 1μg/kg.[Conclusions]The method has good selectivity and strong anti-interference ability,and can meet the requirements of 10 kinds ofα2-receptor agonists residues in animal derived food. 展开更多
关键词 Animal derived food α_(2)-receptor agonist Solid-phase extraction Ultra-high performance liquid phase-triple quadrupole/linear ion trap composite mass spectrometry
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Research on the Upper Limit of Accuracy for Predicting Theoretical Tandem Mass Spectrometry
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作者 Changjiu He Xiaoyu Wang +1 位作者 Mingming Lyu Xinye Bian 《Journal of Computer and Communications》 2024年第3期184-195,共12页
In recent years, numerous theoretical tandem mass spectrometry prediction methods have been proposed, yet a systematic study and evaluation of their theoretical accuracy limits have not been conducted. If the accuracy... In recent years, numerous theoretical tandem mass spectrometry prediction methods have been proposed, yet a systematic study and evaluation of their theoretical accuracy limits have not been conducted. If the accuracy of current methods approaches this limit, further exploration of new prediction techniques may become redundant. Conversely, a need for more precise prediction methods or models may be indicated. In this study, we have experimentally analyzed the limits of accuracy at different numbers of ions and parameters using repeated spectral pairs and integrating various similarity metrics. Results show significant achievements in accuracy for backbone ion methods with room for improvement. In contrast, full-spectrum prediction methods exhibit greater potential relative to the theoretical accuracy limit. Additionally, findings highlight the significant impact of normalized collision energy and instrument type on prediction accuracy, underscoring the importance of considering these factors in future theoretical tandem mass spectrometry predictions. 展开更多
关键词 Tandem mass spectrometry Spectral Prediction Theoretical Limit
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Study on Methanol Oxidation at Pt and PtRu Electrodes by Combining in situ Infrared Spectroscopy and Differential Electrochemical Mass Spectrometry 被引量:1
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作者 陶骞 陈微 +2 位作者 姚瑶 Ammar Bin Yousaf 陈艳霞 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 2014年第5期541-547,I0003,共8页
Methanol oxidation reaction (MOR) at Pt and Pt electrode surface deposited with various amounts of Ru (denoted as PtxRuy, nominal coverage y is 0.17, 0.27, and 0.44 ML) in 0.1 mol/L HClO4+0.5 mol/L MeOH has been ... Methanol oxidation reaction (MOR) at Pt and Pt electrode surface deposited with various amounts of Ru (denoted as PtxRuy, nominal coverage y is 0.17, 0.27, and 0.44 ML) in 0.1 mol/L HClO4+0.5 mol/L MeOH has been studied under potentiostatic conditions by in situ FTIR spectroscopy in attenuated-total-reflection con guration and di erential electro-chemical mass spectrometry under controlled flow conditions. Results reveal that (i) CO is the only methanol-related adsorbate observed by IR spectroscopy at all the Pt and PtRu electrodes examined at potentials from 0.3 V to 0.6 V (vs. RHE); (ii) at Pt0.56Ru0.44, two IR bands, one from CO adsorbed at Ru islands and the other from COL at Pt substrate are detected, while at other electrodes, only a single band for COL adsorbed at Pt is observed; (iii) MOR activity decreases in the order of Pt0.73Ru0.27〉Pt0.56Ru0.44〉Pt0.83Ru0.17〉Pt; (iv) at 0.5 V, MOR at Pt0.73Ru0.27 reaches a current e ciency of 50% for CO2 production, the turn-over frequency from CH3OH to CO2 is ca. 0.1 molecule/(site sec). Suggestions for further improving of PtRu catalysts for MOR are provided. 展开更多
关键词 Differential electrochemical mass spectrometry Electrochemical in situ infrared spectroscopy Methanol oxidation PtRu electrode Current efficiency
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Using Matrix-assisted laser desorption/ionization time-of-flight mass spectrometry to analyze differentially expressed brain polypeptides in scrapie strain 22L-infected BALB/c mice 被引量:1
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作者 Xiangyu Liao Jiayu Wan +7 位作者 Wensen Liu Xin Tang Wufei Zhu Na XU Jing Xu Nan Li Yaping Chang Chuanjing Ju 《Neural Regeneration Research》 SCIE CAS CSCD 2011年第23期1801-1805,共5页
Differentialiy expressed polypeptides in the brain of a BALB/c mouse model infected with scrapie strain 22L were analyzed by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry. The results sh... Differentialiy expressed polypeptides in the brain of a BALB/c mouse model infected with scrapie strain 22L were analyzed by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry. The results showed that 21 peptides were down-regulated, with peptides of mass-to-charge ratio 758.772 5 and mass-to-charge ratio 5 432.206 9, demonstrating the most significant decreases. These finding suggest that these peptides are candidate biomarkers and may play an important role in the pathogenesis of prion disease. 展开更多
关键词 prion diseases misfolded prion protein imaging mass spectrometry PEPTIDES biological markers 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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Studies on Fragmentation Pathways of N-Ethoxy(phenyl) phosphoryl Amino Acids by Electrospray Ionization Tandem Mass Spectrometry
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作者 CAO Shu-xia LI Hong-wei +2 位作者 GUO Yan-chun LIAO Xin-cheng ZHAO Yu-fen 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 2006年第5期598-601,共4页
The positive and negative ESI-MS/MS spectra of N-ethoxy(phenyl) phosphoryl amino acids(EPP-AA) were investigated by electrospray ionization(ESI) ion trap mass spectrometry. The fragmentation pathways of [ M + N... The positive and negative ESI-MS/MS spectra of N-ethoxy(phenyl) phosphoryl amino acids(EPP-AA) were investigated by electrospray ionization(ESI) ion trap mass spectrometry. The fragmentation pathways of [ M + Na]^+ and [ M - H]^- ions are proposed and rationalized. The observation may have some potential applications in the interpretation of the MS/MS spectra of novel N-phosphoryl compounds. The complexity of MS/MS spectra of EPP-AA [ M + Na]^+ ions is decreased compared with that of N-dialkyloxyphosphoryl amino acid. Therefore, the new phosphonamidate method may be considered one of the superior methods that can be used in sequencing peptides and proteins extensively. 展开更多
关键词 N-Ethoxy(phenyl) phosphoryl amino acid Electrospray ionization ion trap mass spectrometry Tandem mass spectrometry
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Analyzing Brazilian Driver’s License Authenticity by Easy Ambient Sonic-Spray Ionization Mass Spectrometry
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作者 Deleon Nascimento Correa Eduardo Morgado Schmidt +6 位作者 Marcos Fernando Franco Jorge Jardim Zacca Werickson Fortunato de Carvalho Rocha Antony de Paula Barbosa Rodrigo Borges Wanderley de Souza Marcos Nogueira Eberlin 《American Journal of Analytical Chemistry》 2016年第4期342-350,共9页
Fast and unequivocal methods of questioned document analysis are essential in forensic science. Here, a desorption/ionization technique, EASI-MS, was assessed for its ability to investigate questioned driver’s licens... Fast and unequivocal methods of questioned document analysis are essential in forensic science. Here, a desorption/ionization technique, EASI-MS, was assessed for its ability to investigate questioned driver’s licenses (DL). Two suspects DL, displaying the same personal data in the proper fields (name and ID numbers), but with different individual photos, showing similar impressions on microscopic analysis, and authentic standards documents specimens were used as test cases. Profiles from authentic DL surface were dominated by a set of few minor ions, mainly from the plasticizers bis(2-ethylhexyl)phthalate and dibutylphthalate. The seized suspect counterfeit DL on points from personal data and photo were, however, dominated by abundant diagnostic ions of m/z 463, 507, 551, 595, 639, 683, which confirmed counterfeiting. Surfynol<sup>&reg;</sup> and Nonoxynol-9<sup>&reg;</sup>, which are common constituents of inkjet printing, were detected in the counterfeiting areas by high-accuracy EASI(+)-FT-ICR MS. The EASI-MS technique is shown therefore to offer an attractive tool for forensic investigation of questioned documents. 展开更多
关键词 Forensic Sciences Questioned Documents Ambient mass spectrometry Easy Ambient Sonic-Spray Ionization mass spectrometry EASI-MS
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Dissociative Electron Attachment to 1,2-Dichlorobenzene using Mass Spectrometry with Phosphor Screen
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作者 宣传进 王旭东 +3 位作者 夏磊 吴斌 李浩 田善喜 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 2014年第6期628-630,I0003,共4页
Anion mass spectrometry is developed on the basis of our home-made anion velocity map imaging apparatus. The Cl^-; product efficiency curve for dissociative electron attachment to 1,2-dichlorobenzene is obtained from ... Anion mass spectrometry is developed on the basis of our home-made anion velocity map imaging apparatus. The Cl^-; product efficiency curve for dissociative electron attachment to 1,2-dichlorobenzene is obtained from 0.2 to 8 eV, meanwhile the sliced images of this anion are recorded at 1.2 and 6.0 eV corresponding to two peak positions of the product efficiency curve. 展开更多
关键词 Dissociative electron attachment 1 2-Dichlorobenzene Anion mass spectrometry
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Detection of 36 antibiotics in coastal waters using high performance liquid chromatography-tandem mass spectrometry 被引量:13
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作者 那广水 顾佳 +4 位作者 葛林科 张蓬 王震 刘春阳 张琳 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2011年第5期1093-1102,共10页
Among pharmaceuticals and personal care products released into the aquatic environment, antibiotics are of particular concern, because of their ubiquity and health effects. Although scientists have recently paid more ... Among pharmaceuticals and personal care products released into the aquatic environment, antibiotics are of particular concern, because of their ubiquity and health effects. Although scientists have recently paid more attention to the threat of antibiotics to coastal ecosystems, researchers have often focused on relatively few antibiotics, because of the absence of suitable analytical methods. We have therefore developed a method for the rapid detection of 36 antibiotic residues in coastal waters, including tetracyclines (TCs), sulfanilamides (SAs), and quinolones (QLs). The method consists of solid-phase extraction (SPE) and liquid chromatography-tandem mass spectrometry (LC-MS/MS) analysis, using electrospray ionization (ESI) in positive mode. The SPE was performed with Oasis HLB and Oasis MCX cartridges. Chromatographic separation on a Cr8 column was achieved using a binary eluent containing methanol and water with 0.1% formic acid. Typical recoveries of the analytes ranged from 67.4% to 109.3% at a fortification level of 100 ng/L. The precision of the method, calculated as relative standard deviation (RSD), was below 14.6% for all the compounds. The limits of detection (LODs) varied from 0.45 pg to 7.97 pg. The method was applied to detemaine the target analytes in coastal waters of the Yellow Sea in Liaoning, China. Among the tested antibiotics, 31 were found in coastal 'waters, with their concentrations between the LOD and 212.5 ng/L. These data indicate that this method is valid for analysis of antibiotics in coastal waters. The study first reports such a large number of antibiotics along the Yellow Sea coast of Liaoning, and should facilitate future comprehensive evaluation of antibiotics in coastal ecosystems 展开更多
关键词 ANTIBIOTICS high performance liquid chromatography-tandem mass spectrometry SOLID-PHASEEXTRACTION coastal waters
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Offline two-dimensional liquid chromatography coupled with ion mobility-quadrupole time-of-flight mass spectrometry enabling fourdimensional separation and characterization of the multicomponents from white ginseng and red ginseng 被引量:9
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作者 Tiantian Zuo Chunxia Zhang +7 位作者 Weiwei Li Hongda Wang Ying Hu Wenzhi Yang Li Jia Xiaoyan Wang Xiumei Gao Dean Guo 《Journal of Pharmaceutical Analysis》 SCIE CAS CSCD 2020年第6期597-609,共13页
Inherent complexity of plant metabolites necessitates the use of multi-dimensional information to accomplish comprehensive profiling and confirmative identification.A dimension-enhanced strategy,by offline two-dimensi... Inherent complexity of plant metabolites necessitates the use of multi-dimensional information to accomplish comprehensive profiling and confirmative identification.A dimension-enhanced strategy,by offline two-dimensional liquid chromatography/ion mobility-quadrupole time-of-flight mass spectrometry(2 D-LC/IM-QTOF-MS)enabling four-dimensional separations(2 D-LC,IM,and MS),is proposed.In combination with in-house database-driven automated peak annotation,this strategy was utilized to characterize ginsenosides simultaneously from white ginseng(WG)and red ginseng(RG).An offline 2 DLC system configuring an Xbridge Amide column and an HSS T3 column showed orthogonality 0.76 in the resolution of ginsenosides.Ginsenoside analysis was performed by data-independent high-definition MSE(HDMSE)in the negative ESI mode on a Vion?IMS-QTOF hybrid high-resolution mass spectrometer,which could better resolve ginsenosides than MSEand directly give the CCS information.An in-house ginsenoside database recording 504 known ginsenosides and 58 reference compounds,was established to assist the identification of ginsenosides.Streamlined workflows,by applying UNIFI?to automatedly annotate the HDMSEdata,were proposed.We could separate and characterize 323 ginsenosides(including 286 from WG and 306 from RG),and 125 thereof may have not been isolated from the Panax genus.The established 2 D-LC/IM-QTOF-HDMSEapproach could also act as a magnifier to probe differentiated components between WG and RG.Compared with conventional approaches,this dimensionenhanced strategy could better resolve coeluting herbal components and more efficiently,more reliably identify the multicomponents,which,we believe,offers more possibilities for the systematic exposure and confirmative identification of plant metabolites. 展开更多
关键词 Dimension-enhanced strategy Multicomponent characterization GINSENOSIDE Offline two-dimensional liquid chromatography Ion mobility-quadrupole time-of-flight mass spectrometry In-house database
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Determination of trace elements in high purity nickel by high resolution inductively coupled plasma mass spectrometry 被引量:11
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作者 聂西度 梁逸曾 +1 位作者 唐有根 谢华林 《Journal of Central South University》 SCIE EI CAS 2012年第9期2416-2420,共5页
The contents ofMg, Al, Si, Ti, Cr, Mn, Fe, Co, Cu, Ga, As, Se, Cd, Sb, Pb and Bi in high purity nickel were determined by high resolution inductively coupled plasma mass spectrometry (HR-ICP-MS). The sample was diss... The contents ofMg, Al, Si, Ti, Cr, Mn, Fe, Co, Cu, Ga, As, Se, Cd, Sb, Pb and Bi in high purity nickel were determined by high resolution inductively coupled plasma mass spectrometry (HR-ICP-MS). The sample was dissolved in HNO3 and HCI by microwave digestion. Most of the spectral interferences could be avoided by measuring in the high resolution mode. The matrix effects because of the presence of excess HC1 and nickel were evaluated. Correction for matrix effects was made using Sc, Rh and T1 as internal standards. The optimum conditions for the determination were tested and discussed. The detection limits range from 0.012 to 1.76 ~tg/g depending on the type of elements. The applicability of the proposed method is also validated by the analysis of high purity nickel reference material (NIST SRM 671). The relative standard deviation (RSD) is less than 3.3%. Results for determination of trace elements in high purity nickel were presented. 展开更多
关键词 high resolution inductively coupled plasma mass spectrometry high purity nickel trace element matrix effect internal standard
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Quantification of trace amounts of impurities in high purity cobalt by high resolution inductively coupled plasma mass spectrometry 被引量:10
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作者 XIE Hualin HUANG Kelong +1 位作者 NIE Xidu TANG Yougen 《Rare Metals》 SCIE EI CAS CSCD 2007年第3期286-291,共6页
A An analytical method using high resolution inductively coupled plasma mass spectrometry (HR-ICP-MS) for rapid simultaneous determination of 24 elements (Be, Mg, A1, Ti, V, Cr, Mn, Fe, Ni, Cu, Zn, Ga, Ge, As, Se, ... A An analytical method using high resolution inductively coupled plasma mass spectrometry (HR-ICP-MS) for rapid simultaneous determination of 24 elements (Be, Mg, A1, Ti, V, Cr, Mn, Fe, Ni, Cu, Zn, Ga, Ge, As, Se, Mo, Ag, Cd, Sn Sb, Ba, Pt, Au, and Pb) in high purity cobalt was described. Sample digestions were performed in closed microwave vessels using HNO3 and HCI. The matrix effects because of the presence of excess HCI and Co were evaluated. The usefulness of high mass resolution for overcoming some spectral interference was demonstrated. The optimum conditions for the determination were tested and discussed. The standard addition method was employed for quantitative analysis. The detection limits were 0.016-1.50 ].tg·g^-1, the recovery ratios were 92.2%-111.2%, and the RSD was less than 3.6%. The method was accurate, quick, and convenient. It was applied to the determination of trace impurities in high purity cobalt with satisfactory results. 展开更多
关键词 high resolution inductively coupled plasma mass spectrometry high purity cobalt trace impurities matrix effect standard addition method
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Proteome analysis of round-headed and normal spermatozoa by 2-D fluorescence difference gel electrophoresis and mass spectrometry 被引量:9
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作者 Ting-Ting Liao Zhen Xiang Wen-Bing Zhu Li-Qing Fan 《Asian Journal of Andrology》 SCIE CAS CSCD 2009年第6期683-694,共12页
Globozoospermia is a severe form of teratozoospermia characterized by round-headed spermatozoa with an absent acrosome, an aberrant nuclear membrane and midpiece defects. Globozoospermia is diagnosed by the presence o... Globozoospermia is a severe form of teratozoospermia characterized by round-headed spermatozoa with an absent acrosome, an aberrant nuclear membrane and midpiece defects. Globozoospermia is diagnosed by the presence of 100% round-headed spermatozoa on semen analysis, and patients with this condition are absolutely infertile. The objective of this study was to investigate the differences in protein expression between human round- headed and normal spermatozoa. Two-dimensional (2-D) fluorescence difference gel electrophoresis (DIGE) coupled with mass spectrometry (MS) was used in this study. Over 61 protein spots were analysed in each paired normal/round-headed comparison, using DIGE technology along with an internal standard. In total, 35 protein spots identified by tandem mass spectrometry (MS/MS) exhibited significant changes (paired t-test, P 〈 0.05) in the expression level between normal and round-headed spermatozoa. A total of nine proteins were found to be upregulated and 26 proteins were found to be downregulated in round-headed spermatozoa compared with normal spermatozoa. The differentially expressed proteins that we identified may have important roles in a variety of cellular processes and structures, including spermatogenesis, cell skeleton, metabolism and spermatozoa motility. 展开更多
关键词 differential protein GLOBOZOOSPERMIA mass spectrometry (MS) two-dimensional difference gel electrophoresis (2-D DIGE)
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Determination of constituents of essential oil from Angelica sinensis by gas chromatographymass spectrometry 被引量:13
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作者 吴名剑 孙贤军 +3 位作者 戴云辉 郭方遒 黄兰芳 梁逸曾 《Journal of Central South University of Technology》 EI 2005年第4期430-436,共7页
Gas chromatographymass spectrometry (GC-MS) coupled with chemometric resolution upon two- dimensional data was employed to analyze the constituents of essential oils of Angelica sinensis. Constituents in essential oil... Gas chromatographymass spectrometry (GC-MS) coupled with chemometric resolution upon two- dimensional data was employed to analyze the constituents of essential oils of Angelica sinensis. Constituents in essential oils of Angelica sinensis root were identified by GC-MS with the help of subwindow factor analysis (SFA) method resolving two-dimensional original data into mass spectra and chromatograms. 76 of 97 separated constituents in essential oil of Angelica sinensis root were identified and quantified, and they account for about 91.36% of the total content. The results show that ligustilide, butylene phthalide, 2-methoxy-4-vinylphenol, carvacrol, allo-ocimene,2,6,6-trimethylbicyclo-[3,1,1]hept-2-ene are the main constituents in essential oil of Angelica sinensis root. 展开更多
关键词 Angelica sinensis CHEMOMETRICS gas chromatography- mass spectrometry subwindow factor analysis
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Mass spectrometry-based serum peptide profiling in hepatocellular carcinoma with bone metastasis 被引量:8
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作者 Jian He Zhao-Chong Zeng +1 位作者 Zuo-Lin Xiang Ping Yang 《World Journal of Gastroenterology》 SCIE CAS 2014年第11期3025-3032,共8页
AIM: To investigate the potential of serum peptides as a diagnostic tool for hepatocellular carcinoma (HCC) with bone metastasis.
关键词 Hepatocellular carcinoma SERUM PEPTIDES Matrix-assisted laser desorption ionization-time of flight mass spectrometry Tumor biomarker
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Screening potential mitochondria-targeting compounds from traditional Chinese medicines using a mitochondria-based centrifugal ultrafiltration/liquid chromatography/mass spectrometry method 被引量:5
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作者 Xing-Xin Yang Yu-Zhen Zhou +5 位作者 Feng Xu Jie Yu Gegentana Ming-Ying Shang Xuan Wang Shao-Qing Cai 《Journal of Pharmaceutical Analysis》 SCIE CAS CSCD 2018年第4期240-249,共10页
Mitochondria regulate numerous crucial cell processes, including energy production, apoptotic cell death, oxidative stress, calcium homeostasis and lipid metabolism. Here, we applied an efficient mitochondria-based ce... Mitochondria regulate numerous crucial cell processes, including energy production, apoptotic cell death, oxidative stress, calcium homeostasis and lipid metabolism. Here, we applied an efficient mitochondria-based centrifugal ultrafiltration/liquid chromatography/mass spectrometry(LC/MS) method,also known as screening method for mitochondria-targeted bioactive constituents(SM-MBC). This method allowed searching natural mitochondria-targeting compounds from traditional Chinese medicines(TCMs), including Puerariae Radix(PR) and Chuanxiong Radix(CR). A total of 23 active compounds were successfully discovered from the two TCMs extracts. Among these 23 hit compounds, 17 were identified by LC/MS, 12 of which were novel mitochondria-targeting compounds. Among these, 6 active compounds were analyzed in vitro for pharmacological tests and found able to affect mitochondrial functions. We also investigated the effects of the hit compounds on Hep G2 cell proliferation and on loss of cardiomyocyte viability induced by hypoxia/reoxygenation injury. The results obtained are useful for in-depth understanding of mechanisms underlying TCMs therapeutic effects at mitochondria level and for developing novel potential drugs using TCMs as lead compounds. Finally, we showed that SM-MBC was an efficient protocol for the rapid screening of mitochondria-targeting constituents from complex samples such as PR and CR extracts. 展开更多
关键词 MITOCHONDRIA Bioactive constituents Traditional Chinese medicines Centrifugal ultrafiltration Liquid chromatography/mass spectrometry
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