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本文采用FDMS和DElMS对4种新型火药进行了质谱分析,均得到了很强的分子离子峰和特征碎片峰,并对样品A进行了DEIMS的亚稳分析,得出了该类化合物的裂解规律为:M-n(NO),M-n(O),M-n(NO_2),M-n(HNO_2),M-n(OH)等。 相似文献
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面对大气、河流、土壤等化学污染,各种突发性爆炸事故和化学泄漏事件,以及生化武器滥用等等社会问题,迫切需要对源头进行现场原位检测分析.质谱(MS)以其检测速度快、灵敏度高、检测样品量少、可对未知物定性定量检测等特点,非常适合应用于这些现场的分析检测.然而实验室用MS的体积、重量、功耗等较大,不便于搬运,无法实现现场的原位检测.近年来,便携式质谱仪的出现,使得现场原位质谱分析成为可能,并且随着人们对原位质谱分析的要求越来越高,便携式质谱仪从质量分析器、迸样方法,以及真空系统等方面进行了不断改进,并在临床诊断、食品质量控制、法医学、环境学等多个领域发挥了重要作用.文章对近年来便携式质谱仪的发展进行了梳理,并对仪器及其相关部件的未来发展趋势进行了展望. 相似文献
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该文对质谱鉴定技术及其与色谱联用的分析方法(包括直接进样质谱分析、气相色谱质谱联用技术、超临界流体与质谱联用技术和液相色谱质谱联用技术)在甘油三酯分析方面的应用进行了综述,评述了各类分析方法的优缺点,对常用的脂质分析数据库进行了介绍,并对甘油三酯分析方法的发展及应用作了展望. 相似文献
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电喷雾解吸电离质谱法用于临床尿样的直接分析 总被引:3,自引:1,他引:2
将电喷雾解吸电离质谱(DESI-MS)用于临床尿样的分析, 优化了电喷雾溶剂流速、电喷雾电压和喷雾锥距离等重要参数. 采用普通滤纸作为样品载体, 在不需要样品预处理的前提下同时快速测定了临床尿样中的钾、钠、尿素、尿酸、丙酮酸和肌苷等多种成分, 并对各种成分的主要离子进行了串联质谱鉴定. DESI-MS在进行多组分同时测定时不需要进行样品预处理, 缩短了测定时间, 单个样品的分析时间不到1 min. 同时, 采用内标法对所测定组分进行了半定量分析. 相似文献
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烷基苯磺酸盐的电喷雾离子化质谱和碰撞活化解离质谱-质谱分析 总被引:4,自引:0,他引:4
用正,负电喷雾电离(ESI)并结合碰撞活化解离(CAD)质谱法对烷基苯磺酸盐(ABS)进行鉴定,无论正,负离子化过程中均不出现快原子轰击质谱常见的碎片峰,由于没有复杂碎片峰的干扰,ESI-MS对分析ABS试样大为有利,正离子ESI-MS对支化ABS鉴定的灵敏度远低于负离子ESI-MS,用CAD-MS对ESI-ME谱各主要峰进行了归属,线型与支化ABS相对含量可以用负离子ESI-MS求出,负离子化ESI-MS是快速,有效和可靠的鉴定,ABS的方法。 相似文献
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现代质谱技术在天然药物结构和药物代谢物研究中的应用概述 总被引:1,自引:0,他引:1
天然药物结构研究是一项重要的项目。从天然药物中分离得到的单体,如果结构不清楚,即使具有很强的活性和较大的安全性,也无法进一步开展其药效学和毒理学研究,也就谈不上进行高质量的新药研究开发,也不可能进行人工合成或结构修饰、改造等工作,其应用价值将大大降低。在天然药物结构研究中,在通过理化方法对化合物类型初步断定后,还需通过谱学方法对其相对分子质量、官能团、不饱和度、分子式等进行进一步研究。质谱可用于确定相对分子质量及求算分子式和提供其它结构信息。此外,在一定条件下化合物的碎裂遵循一定的规律,通过比较试样与标准品在同一装置,同一条件下测得的质谱图,可以鉴定是否为同一化合物。对于未知化合物,可由分子离子丢失的碎片大小或由碎片离子的m/z值及碎裂特征推定或者复核分子的部分结构。 相似文献
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Mengxi Wu Haoyang Wang Guoqing Dong Brian D. Musselman Charles C. Liu Yinlong Guo 《中国化学》2015,33(2):213-219
A method for rapid identification and quantification of phthalate plasticizers in beverages was developed. A number of 15 phthalate plasticizers which covered all the phthalates concerned in the US Consumer Product Safety Improvement Act (CPSIA), European Union legislations and Chinese national standards (GB) were analyzed. By a combined solid‐phase micro‐extraction (SPME) and direct analysis in real time mass spectrometry (DART‐MS) approach, phthalates at sub‐ng·mL?1 levels can be qualitatively and quantitatively analyzed in a short time. The use of ultrahigh‐resolving power and the accurate mass measurement capacity naturally provided by Fourier transform ion cyclotron resonance mass spectrometry (FT‐ICR‐MS) minimizes the matrix interferences and thus enables the evaluation of phthalates in a complex matrix without extensive sample handlings or preparations. The limits of quantification (LOQs) were estimated to be at 0.3–5.0 ng·mL?1, lower than the Maximum Residue Limit (MRL) regulated by the European Union legislations (2007/19/EC) in foods, beverages, food packaging and toys (0.3–30 ng·mL?1). This rapid and easy‐to‐use SPME‐DART‐FT‐ICR‐MS method provided a relatively high‐throughput and powerful analytical approach for quick testing and screening phthalates in beverages and water samples to ensure food safety. 相似文献
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Julia L. Rummel Amy M. McKenna Alan G. Marshall John R. Eyler David H. Powell 《Rapid communications in mass spectrometry : RCM》2010,24(6):784-790
Direct Analysis in Real Time (DART) is an ambient ionization technique for mass spectrometry that provides rapid and sensitive analyses with little or no sample preparation. DART has been reported primarily for mass analyzers of low to moderate resolving power such as quadrupole ion traps and time‐of‐flight (TOF) mass spectrometers. In the current work, a custom‐built DART source has been successfully coupled to two different Fourier transform ion cyclotron resonance (FT‐ICR) mass spectrometers for the first time. Comparison of spectra of the isobaric compounds, diisopropyl methylphosphonate and theophylline, acquired by 4.7 T FT‐ICR MS and TOF MS, demonstrates that the TOF resolving power can be insufficient for compositionally complex samples. 9.4 T FT‐ICR MS yielded the highest mass resolving power yet reported with DART ionization for 1,2‐benzanthracene and 9,10‐diphenylanthracene. Polycyclic aromatic hydrocarbons exhibit a spatial dependence in ionization mechanisms between the DART source and the mass spectrometer. The feasibility of analyzing a variety of samples was established with the introduction and analysis of food products and crude oil samples. DART FT‐ICR MS provides complex sample analysis that is rapid, highly selective and information‐rich, but limited to relatively low‐mass analytes. Copyright © 2010 John Wiley & Sons, Ltd. 相似文献
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Nayara A. dos Santos Clebson J. Macrino Joo Francisco Allochio Filho Fernanda F. Gonalves Camila M. Almeida Fabiana Agostini Tainara Guizolfi Sidnei Moura Valdemar Lacerda Paulo R. Filgueiras Rafael S. Ortiz Wanderson Romo 《Journal of mass spectrometry : JMS》2020,55(10)
The consumption of design drugs, frequently known as new psychoactive substances (NPS), has increased considerably worldwide, becoming a severe issue for the responsible governmental agencies. These illicit substances can be defined as synthetic compounds produced in clandestine laboratories in order to act as analogs of schedule drugs mimetizing its chemical structure and improving its pharmacological effects while hampering the control and making regulation more complicated. In this way, the development of new methodologies for chemical analysis of NPS drugs is indispensable to determine a novel class of drugs arising from the underground market. Therefore, this work shows the use of high‐resolution mass spectrometry Fourier transform ion cyclotron resonance mass spectrometry (FT‐ICR MS) applying different ionization sources such as paper spray ionization (PSI) and electrospray ionization (ESI) in the evaluation of miscellaneous of seized drugs samples as blotter paper (n = 79) and tablet (n = 100). Also, an elucidative analysis was performed by ESI(+)MS/MS experiments, and fragmentation mechanisms were proposed to confirm the chemical structure of compounds identified. Besides, the results of ESI(+) and PSI(+)‐FT‐ICR MS were compared with those of GC–MS, revealing that ESI(+)MS showed greater detection efficiency among the methodologies employed in this study. Moreover, this study stands out as a guide for the chemical analysis of NPS drugs, highlighting the differences between the techniques of ESI(+)‐FT‐ICR MS, PSI(+)‐FT‐ICR MS, and GC–MS. 相似文献
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采用改进的碱液萃取方法分离杜巴原油中的酸性化合物(主要是环烷酸),通过高分辨质谱分析萃取过程中不同组分酸性化合物组成,以研究碱萃取前后酸性化合物的分布与组成特征。实验结果表明,电喷雾傅立叶变换离子回旋共振高分辨质谱(ESI-FT-ICR-MS)是分析原油中酸性化合物的强有力的手段;酸性化合物分布于碱萃取前后的各个组分中,但其组成有明显的差异,碱液萃取出的石油酸主要是相对分子质量小于500的酸性组分,增加反萃取溶剂的用量和极性有利于脱除萃取物中的非碱性氮化合物,对石油羧酸的组成影响不大。 相似文献
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Zhongqi He Rachel L. Sleighter Patrick G. Hatcher Shasha Liu Fengchang Wu Haixuan Zou O. Modesto Olanya 《Journal of mass spectrometry : JMS》2019,54(8):655-666
Soluble extractives in wood function to protect living trees from destructive agents and also contribute to wood color and fragrance. Some extractive components have biological activities with medical applications. They also play important roles in wood processing and related applications. To increase the knowledge of wood chemistry, maple and oak were extracted by water. Ultraviolet/visible (UV/vis) spectroscopy indicated the presence of a phenolic compound, resorcinol, in maple extractives having higher molecular mass and more aromatic components than oak extractives. Negative and positive electrospray ionization Fourier transform ion cyclotron resonance mass spectrometry (ESI FT‐ICR‐MS) identified thousands of formulas in the two samples in the m/z range of 200 to 800. They mainly fall into the lignin‐like, carbohydrate‐like, and tannin‐like compound categories. The top 25 peaks (ie, formulas) with the highest relative magnitude in negative ESI represented nearly 50% of the summed total spectral magnitude of all formulas assigned in the maple and oak extractives. Furthermore, the base peak (ie, most abundant peak) accounted for about 14% of the total abundance in each wood sample. Literature comparisons identified 17 of 20 formulas in the top five peaks of the four spectra as specific bioactive compounds in trees and other plants, implying the potential to explore utilization of maple and oak extractives for functional and medicinal applications. The various profiling of the top 25 peaks from the two samples also suggested the possible application of FT‐ICR‐MS for detecting chemical markers useful in profiling and identification of wood types and sources. 相似文献
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Abayomi D. Olaitan Behrooz Zekavat Touradj Solouki 《Journal of mass spectrometry : JMS》2016,51(1):12-19
Radio‐frequency ionization (RFI) is a novel ionization method coupled to mass spectrometry (MS) for analysis of semi‐volatile and volatile organic compounds (VOCs). Despite the demonstrated capabilities of RFI MS for VOC analysis in both positive‐ and negative‐ion modes, mechanism of RFI is not completely understood. Improved understanding of the ion generation process in RFI should expand its utility in MS. Here, we studied the possibility of electron emission in RFI using both direct charged particle current measurements and indirect electron detection in a 9.4‐T Fourier transform‐ion cyclotron resonance (FT‐ICR) mass spectrometer. We show that RF‐generated electrons can be trapped in the ICR cell and, subsequently, reacted with neutral hexafluorobenzene (C6F6) molecules to generate C6F6●?. Intensity of observed C6F6●? species correlated with the number of trapped electrons and decreased as a function of electron quenching period. We also measured the electron attachment rate constant of hexafluorobenzene using a post‐RF electron trapping experiment. Measured electron attachment rate constant of hexafluorobenzene (1.19 (±0.53) × 10?9 cm3 molecule?1 s?1) for post‐RF FT‐ICR MS agreed with the previously reported value (1.60 (±0.30) × 10?9 cm3 molecule?1 s?1) from low‐pressure ICR MS measurements. Experimental results from direct and indirect electron measurements suggest that RFI process involves RF‐generated electrons under ultrahigh vacuum conditions. Copyright © 2015 John Wiley & Sons, Ltd. 相似文献
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Hyo‐Jik Yang Kyu Hwan Park Dong Wan Lim Hyun Sik Kim Jeongkwon Kim 《Rapid communications in mass spectrometry : RCM》2012,26(6):621-630
A combination of methodologies using the extremely high mass accuracy and resolution of 15‐T Fourier transform ion cyclotron resonance (FT‐ICR) mass spectrometry (MS) was introduced for the identification of intact cancer cell phospholipids. Lipids from a malignant glioma cell line were initially analyzed at a resolution of >200 000 and identified by setting the mass tolerance to ±1 mDa using matrix‐assisted laser desorption/ionization (MALDI) 15‐T FT‐ICR MS in positive ion mode. In most cases, a database search of potential lipid candidates using the exact masses of the lipids yielded only one possible chemical composition. Extremely high mass accuracy (<0.1 ppm) was then attained by using previously identified lipids as internal standards. This, combined with an extremely high resolution (>800 000), yielded well‐resolved isotopic fine structures allowing for the identification of lipids by MALDI 15‐T FT‐ICR MS without using tandem mass spectrometric (MS/MS) analysis. Using this method, a total of 38 unique lipids were successfully identified. Copyright © 2012 John Wiley & Sons, Ltd. 相似文献
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Fourier-transform ion cyclotron resonance mass spectrometry has developed into one of the most powerful analytical techniques. This unique technique enables acquisition of high-resolution mass spectra with high accuracy, which in turn enables determination of the elemental composition of the analyzed compounds. Coupling with liquid chromatography affords a separation technique with a high-resolution detector which can be used to investigate very complex matrices. In this review some important instrumental developments are described and applications are presented; these show the advantages and disadvantages of this combination.Abbreviations CAD
Collision-activated dissociation
- CZE
Capillary zone electrophoresis
- ECD
Electron-capture dissociation
- FT
Fourier-transform
- MS
Mass spectrometry
- ICR
Ion cyclotron resonance
- IRMPD
Infrared multi-photon dissociation
- LC
Liquid chromatography
- LSIMS
Liquid secondary-ion mass spectrometry
- SORI
Sustained off-resonance irradiation
This contribution is dedicated to Professor Dr M.T. Reetz on the occasion of his 60th birthday. 相似文献
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This article provides a review of the use of modern mass spectrometry (MS) for quantitative and qualitative measurements of organic phosphorus compounds in nature. Included is a brief discussion of recent developments in large molecule mass spectrometry, focusing on time-of-flight (TOF) and ion cyclotron resonance (ICR) mass analysis techniques, as well as electrospray (ESI) and inductively coupled plasma (ICP) ionization. The use of ICP with high-resolution mass spectrometry for quantitative measurements of total phosphorus and as a detector coupled to HPLC and CE for defining organic phosphorus speciation is demonstrated using results from a study of phosphorus cycling in a treatment wetland. Qualitative identifications of individual phosphorus compounds by ultrahigh resolution Fourier-transform ion cyclotron resonance mass spectrometry (FT-ICR MS) is demonstrated using dissolved organic phosphorus isolated from this same wetland. 相似文献