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Detection of Serine Octamer by Desorption Electrospray Ionization Mass Spectrometry in Resultant Mixture of Aspartic Acid Exposed to Sunshine Under Natural Conditions

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Chemical Research in Chinese Universities 2007年第6期23卷 650-653页

作者： chen huan-wen LI Ming JIN Wei JIN Qin-han ZHENG Jian College of Chemistry Jilin Province Research Center of Engineering and Technology for Spectral Instruments Jilin University Changchun 130021 P. R. China Applied Chemistry Department East China University of Technology Fuzhou 344000 P. R. China College of Information Science and Engineering Zhejiang University Hangzhou 310027 P. R. China Beijing Physical and Chemical Analysis Center Beijing 100089 P. R. China

Serine, one of the nonessential amino acids, is of principal interest because of its capability to form magic-number ionic clusters, which provide a remarkable preference for homochirality. With L-aspartic acid as the precursor, this study provides experimental evidence for serine formation in weak acidified aqueous solutions in the presence of iron, with exposure to sunlight, which simulates the natural conditions of the prebiotic aqueous environment. The resultant mixture is directly analyzed via desorption electrospray ionization mass spectrometry（ DESI-MS）, without any sample preseparation. The serine monomer is successfully detected as protonated molecules, giving a peak at m/z 106, which is confirmed by the MS/MS fragments. Protonated serine octamer（ m/z 841 ） is also observed with significant abundance in the MS spectra and is confirmed by the MS/MS data, which shows the formation of the serine octamer by a synthesized serine in the resultant mixture. It is also found that the serine octamer yielded equivalent abundance in the DESI mass spectra in a wide pH range（pH = 1-5 ）, and that existence of ferrous salt and sunshine are essential for the conversion of aspartic acid to serine in the acidic water solution.

关键词： Serine octamer Aspartic acid Photocatalysis DESI Mass spectrometry

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Iodine Determination by Microwave Plasma Torch Atomic Emission Spectrometer Coupled with Online Preconcentration Vapor Generation Technique

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Chemical Research in Chinese Universities 2008年第5期24卷 546-549页

作者： FEI Yan-qun LUO Gui-min FENG Guo-dong chen huan-wen FEI Qiang huan Yan-fu JIN Qin-han Key Laboratory for Molecular Enzymology and Engineering of Ministry of Education Institute of Analytical Science School of Chemistry Jilin Province Research Center for Engineering and Technology of Spectral Analytical Instruments Jilin University Changchun 130021 P R. China

This article focuses on iodine determination by microwave plasma torch atomic emission spectrometry （MPT-AES） coupled with online preconcentration vapor generation method. A new desolvation device, multistrand Nafion dryer, was used as the substitute for condenser desolvation system. Some experimental conditions, such as preconcentration time, acidity of sample solution, rinsing solution acidity and dynamic linear range were investigated and optimized. The new desolvation system eliminates the problem of decreasing emission intensity of I（I） 206.238 nm line with the increase of working time on a conventional condenser desolvation system, thus greatly improving the reproducibility.

关键词： MPT-AES On-line preconcentration Vapor generation Nation dryer Membrane desolvation

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Mass Spectrometric Detection of Lysine and Royal Demolition Explosive on Large Surfaces

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Journal of Chinese Mass Spectrometry Society 2017年第5期38卷 515-520页

作者： Li, Yi Zhu, Teng-Gao Wang, Guo-Feng chen, huan-wen Jiangxi Key Laboratory for Mass Spectrometry and Instrumentation East China Institute of Technology Nanchang 330013 China

Ambient ionization mass spectrometry has significantly improved the efficiency of analysis complex matrix sample due to its high sensitivity, selectivity and throughput. At present, direct ionization sources coupled with mass spectrometer including desorption electrospray ionization (DESI), real time online (DART), matrix assisted laser desorption ionization (MALDI), laser ablation electrospray ionization (LAESI), desorption atmospheric pressure chemical ionization (DAPCI), extractive electrospray ionization (EESI) etc. are applied for the direct ionization targeting molecular followed by mass spectrometer characterization. A famous ionization technique namely DESI is the most representative ambient source, which can ionization the polar compounds with bulk solid surface focused on a large number of studies on the detection methods of explosives. However, DESI in the ionization of solid explosives is needed continuous scanning and a single sampling area can not exceeding 1 cm2, resulting in time-consuming and inaccurate enough results. In order to further improve the analysis rate of the large surface sample and decrease the number of scanning for a given sample surface, a novel mass spectrometry method with a single scan was established for detecting trace substance distributed in large sample surface of any position. Using artificial leather surface (length of a side: 4 cm×4 cm) added lysine and royal demolition explosive (RDX) as representative detection object, the triangular metal copper electrode (length of a side: 8.6 cm) which was applied the ionization regent with methanol-water (3:7, V/V) was closed to the sample surface, making the tip of the triangle metal copper electrode on the mass spectrometer entrance. The trace substance form into ions in triangle electrode tip towards mass spectrometry when applying +5.8 kV high voltage on the metal copper electrode. This experimental results show that the novel method with a single scan can detect randomly and no

关键词： Explosives

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Current Application Status of DART-MS in China

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Journal of Chinese Mass Spectrometry Society 2018年第1期39卷 120-128页

作者： Xu, Jia-Quan Xiao, Yi-Po chen, huan-wen Zhang, Xiao-Ping Jiangxi Key Laboratory for Mass Spectrometry and Instrumentation East China University of Technology Nanchang 330013 China

Ambient ionization mass spectrometry has become a hot area in the field of mass spectrometry due to its real-time and in situ analysis recently. As a typical kind of ambient ionization, direct analysis in real-time (DART) has attracted extensive attention since introduced in 2005. Great efforts have been applied in the research of the ionization mechanism and application of DART-MS. Penning ionization, proton transfer, electron capture and transient micro-environment mechanism have been reported involved in the DART ionization process. Due to its advantages of stability, operability, and analysis speed, DART-MS has been widely used in the environment monitoring, food and drug safety, biomedical analysis, and public security administration. Great achievement was inspiring, but several problems still remained, such as quantitative performance and direct analysis of analytes inside bulk sample. Therefore, in this paper, the mechanism of DART, the application of DART-MS in China were briefly summarized and discussed during the past two years, and the development tendency of DART-MS was prospected. © 2018, Editorial Board of Journal of Chinese Mass Spectrometry Society. All right reserved.

关键词： Mass spectrometry

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Study of Uranyl Tartrate Speciation in Aqueous Solution by Electrospray Ionization Tandem Mass Spectrometry

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Journal of Chinese Mass Spectrometry Society 2019年第5期40卷 467-476页

作者： Zeng, Kai chen, huan-wen Luo, Ming-Biao Zhang, Hui Yu, wen-Ting Yang, Ya-Xuan Jiangxi Key Laboratory for Mass Spectrometry and Instrumentation East China University of Technology Nanchang 330013 China Nanchang Key Laboratory of Quality and Safety Evaluation of Traditional Chinese Medicine Nanchang Institute for Food and Drug Control Nanchang 330012 China

As a nuclear fuel, uranium plays an important role in national defense and energy, however, the release of uranium into the natural environment from mining to radioactive waste disposal poses a severe threat to public health and environmental protection. Therefore, investigation of uranium in aqueous solution is one of the important research on geological disposal of high level waste. Electrospray ionization tandem mass spectrometry (ESI-MS/MS) has been applied for trace detection of uranyl complex in the last decade because of its characteristics of accurate qualitative and quantitative capability, strong anti-interference capability and high determination efficiency. In this work, uranyl complex were identified by ESI-MS/MS, where the cations were ionized by ESI, positive charged uranyl tartrate undergoes characteristic fragmentation in the gas phase. Target ions were bombarded to generate product ions at high collision energy of 200 V in collision-induced dissociation (CID) mode, energy of which is far beyond normal range. As [UO2]+ has special mass-to-charge ratio (m/z) compared with other substances and it was split apart hardly, product ion of [UO2]+(m/z 269.9) was the key basis to identify uranium-containing species in ESI-MS/MS. Pretreatment was unessential for the qualitative method which would not change speciation of original solution. It was found 14 kinds of uranyl tartrate and 5 kinds of inorganic uranyl speciation quickly in uranyl nitrate-tartaric acid solution, all of which could generate [UO2]+ signal significantly or even uniquely. Each uranyl group could bind a tartrate anion tightly and was able to complex two tartaric acid molecular maximum. Experiment results showed that clusters of uranyl tartrate such as [(UO2HTarH2Tar)2]2+ and [(UO2)3Tar(HTar)2(H2Tar)2]2+ were identified by ESI-MS/MS for the first time. Despite of losing the acid molecules, there was other mass fragmentation path of uranyl tartrate cluster ions that stable double bonds were

关键词： Uranium dioxide

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复杂样品质谱分析技术的原理与应用

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分析化学 2010年第8期38卷 1069-1088页

作者：陈焕文胡斌张燮东华理工大学化学生物与材料科学学院

原位、实时、在线、非破坏、高通量、低耗损的质谱学方法是质谱分析技术发展的重要趋势。在无需样品预处理的条件下对复杂基体样品中痕量待测物直接离子化技术的出现,极大地提高了质谱分析的效率,使实际样品的快速质谱分析成为可能。本... 详细信息

原位、实时、在线、非破坏、高通量、低耗损的质谱学方法是质谱分析技术发展的重要趋势。在无需样品预处理的条件下对复杂基体样品中痕量待测物直接离子化技术的出现,极大地提高了质谱分析的效率,使实际样品的快速质谱分析成为可能。本文着重综述了能够在无需样品预处理情况下对复杂基体样品离子化的新兴质谱技术及其应用研究,系统阐述了直接离子化技术的基本原理和方法,介绍了几种典型的常压直接离子化技术和装置,对直接离子化质谱分析技术在食品、药品、环境、活体分析、代谢组学、蛋白质组学以及生物组织质谱成像等领域的典型应用进行了述评,讨论了提高复杂样品快速质谱分析选择性的可能方法,并展望了常压直接离子化技术未来发展的可能趋势。

关键词：快速分析质谱直接离子化技术仪器装置评述

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溶液中蛋白质的气液荷电萃取电离质谱研究

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分析化学 2017年第12期45卷 1937-1943页

作者：寇伟张华 Konstantin Chingin 陈焕文吉林大学无机合成与制备化学国家重点实验室东华理工大学江西省质谱科学与仪器重点实验室

利用自主研制的气液荷电萃取电离装置实现了溶液中蛋白组分的荷电萃取电离直接质谱分析。系统考察了所用气体种类、气泡路径长度、溶液电压、气压等条件对溶液中溶菌酶等蛋白荷电萃取电离的影响,以期得到最佳蛋白质信号。在以CO;为萃取... 详细信息

利用自主研制的气液荷电萃取电离装置实现了溶液中蛋白组分的荷电萃取电离直接质谱分析。系统考察了所用气体种类、气泡路径长度、溶液电压、气压等条件对溶液中溶菌酶等蛋白荷电萃取电离的影响,以期得到最佳蛋白质信号。在以CO;为萃取气体、气泡路径长度32 cm、溶液电压+2 k V、气压0.05 MPa条件下,溶菌酶在水、纯水稀释200倍尿液、未稀释尿液中的浓度分别为1×10;mol/L、1×10;mol/L、1×10;mol/L时获得谱图信噪比（S/N≥3）类似,信号强度不受样品管内径大小影响,所用尿液最小体积为6 m L,但对珍稀样品可进一步减少用量。与ESI-MS相比,本方法获得更多低价态蛋白质离子,对溶液中的小分子基体、无机盐具有更强的耐受性,且辣根过氧化物酶经气液苛电萃取电离能保留53.9%活度。本方法具有无需复杂样品预处理、无化学试剂污染的特点,有望为分析复杂基质中蛋白质提供一种新方法。

关键词：蛋白样品气泡荷电萃取电离质谱分析

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甲基羟基铀酰离子与水的复分解反应

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高等学校化学学报 2008年第5期29卷 912-915页

作者：胡斌陈兰慧郇延富张燮李明梁华正陈焕文东华理工大学应用化学系抚州344000 东北师范大学化学学院功能材料研究所长春130024 吉林大学化学学院长春130021

以醋酸铀酰为主要试剂,在负离子检测模式下,采用电喷雾串联质谱法制备了甲基羟基铀酰负离子.实验发现,气相中的甲基羟基铀酰离子与水分子发生分子离子复分解反应,并用串联质谱法对反应产生的离子性产物进行了结构确认,提出了反应的可能... 详细信息

以醋酸铀酰为主要试剂,在负离子检测模式下,采用电喷雾串联质谱法制备了甲基羟基铀酰负离子.实验发现,气相中的甲基羟基铀酰离子与水分子发生分子离子复分解反应,并用串联质谱法对反应产生的离子性产物进行了结构确认,提出了反应的可能机理.热力学计算结果表明,该反应的ΔGReaction为-473.0kJ/mol,ΔHReaction为-236.5 kJ/mol,ΔSSystem为0.792 ***-1.K-1.该反应的速率常数为2.26 s-1.

关键词：气相复分解反应醋酸铀酰电喷雾质谱碰撞诱导解离分子离子反应

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组织样品大气压质谱分析研究

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分析化学 2020年第7期48卷 827-837页

作者：王雨芬卢海艳张华陈焕文吉林大学无机合成与制备化学国家重点实验室东华理工大学江西省质谱科学与仪器重点实验室

组织样品中含有丰富的生物分子信息,是代谢组学、脂质组学、蛋白质组学等研究的物质基础。近年来,大气压质谱分析(AMS)技术因具有无需样品预处理即可直接获取组织样品中生物分子种类及含量信息的能力,在组织样品分析中突显了高通量、高... 详细信息

组织样品中含有丰富的生物分子信息,是代谢组学、脂质组学、蛋白质组学等研究的物质基础。近年来,大气压质谱分析(AMS)技术因具有无需样品预处理即可直接获取组织样品中生物分子种类及含量信息的能力,在组织样品分析中突显了高通量、高灵敏度、高准确性、低样品耗量的特点,已逐渐成为分析组织样品不可或缺的手段。本文以常见的植物、动物和临床术后组织样品为代表,介绍了近年来AMS技术在组织样品分析中的应用进展,结合成像技术,讨论了组织样品AMS的发展趋势。

关键词：大气压质谱组织分析质谱成像评述

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羟基多环芳烃的电喷雾电离离子阱串联质谱检测

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高等学校化学学报 2013年第8期34卷 1840-1844页

作者：李雪方小伟李银萍陈焕文上海大学环境与化学工程学院环境污染与健康研究所上海200444 东华理工大学江西省质谱科学与仪器重点实验室南昌330013

采用电喷雾电离离子阱串联质谱检测了1-/2-羟基萘、2-羟基芴、2-/3-/4-/9-羟基菲、6-羟基屈和3-羟基苯并[a]芘等9种不同环数的羟基多环芳烃(OH-PAHs,2～5环),考察了碰撞诱导解离操作参数活化值Q和相对碰撞能量对羟基多环芳烃各单体碎片... 详细信息

采用电喷雾电离离子阱串联质谱检测了1-/2-羟基萘、2-羟基芴、2-/3-/4-/9-羟基菲、6-羟基屈和3-羟基苯并[a]芘等9种不同环数的羟基多环芳烃(OH-PAHs,2～5环),考察了碰撞诱导解离操作参数活化值Q和相对碰撞能量对羟基多环芳烃各单体碎片离子产率的影响.通过优化活化值Q和相对碰撞能量,得到了3-羟基苯并[a]芘的碎片离子,提高了1-羟基萘、2-羟基芴、3-/9-羟基菲和6-羟基屈碎片离子的产率,并发现活化值Q是电喷雾电离离子阱串联质谱检测不同环数PAHs的关键参数.

关键词：多环芳烃生物标志物羟基多环芳烃离子阱串联质谱碰撞诱导解离

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