微波等离子体炬质谱法对金属元素的分析研究及其拓展应用

发布时间：2018-04-09 01:35

本文选题：微波等离子体炬　切入点：质谱　出处：《东华理工大学》2017年硕士论文

【摘要】：在无需样品预处理的情况下,常压质谱分析方法是一种原位、高通量、低耗损、实时在线、高灵敏度的质谱学方法。随着,常压质谱技术广泛应用,快速分析物质的方法变得极其重要。本文主要采用微波等离子体炬电离质谱(MPT-MS)新技术对金属元素进行分析研究,并开拓MPT-MS直接分析有机物的其它应用(如食品安全、刑事侦查、环境分析等)。本文主要研究内容包括以下五个方面,主要内容为:1.系统地介绍了几种常压等离子体技术的基本原理、方法和装置,重点对微波等离子体炬质谱分析技术在药物、石材、食品及环境等领域的典型应用进行了述评。2.采用新型微波等离子体炬四极杆质谱(MPT-Q-MS)为实验平台,对四极杆质谱仪样机进行性能测试,同时进行离子源电离机理的初步分析。在此基础之上,发展了针对固、液、气态样品的不同进样方式。3.利用微波等离子体炬(MPT)软电离、无Ar背景的特性,在四极杆质谱仪(Q-MS)和线性离子阱质谱仪(LTQ-MS)上进行对比实验。根据Q-MS仪器的特性,对20多种金属元素进行分析研究,并得到水质中金属元素在Q-MS仪器上的初步规律;但因Q-MS仪器无串联质谱功能,为了更好的对水质中金属元素进行分析研究,采用LTQ-MS仪器,在正/负离子模式下对金属元素进行分析研究。研究结果表明:Q-MS仪器对金属元素定量分析的检出限(LOD)能达到商用LTQ-MS仪器相同的数量级(ng·L-1);在Q-MS仪器上金属元素呈现的质谱峰主要为[M]+、[MOH]+、[MO]+,而在LTQ-MS仪器上主要为[M(NO3)a(H2O)b](a-1)+,且LTQ-MS仪器的负离子模式比正离子模式更适合水质中金属元素的定量分析。4.为了拓展MPT源的应用范围,结合MPT高温热效应及电离效应。在无需样品处理的前提下,采用MPT-LTQ-MS对食品领域的大米中黄曲霉毒素进行快速分析,并对多种市售大米品质进行评价,结果表明:该方法线性范围在0.5-20μg·L-1,LOD为0.12μg·L-1。而通过对毒物的分析研究发现,MPT-LTQ-MS方法能为刑事侦查提供一种快速定性分析的手段。为了进一步扩大该方法的应用领域,本文还对农产品中蜂蜜里的四环素进行检测,检测的四种市售蜂蜜中四环素含量均在国标允许范围类。因此,该方法为直接分析有机样品提供了一种新的质谱分析方法。5.总结了微波等离子体炬质谱新技术的应用成果,展望了其以后的发展和应用。
[Abstract]:In the absence of sample pretreatment, atmospheric mass spectrometry is an in-situ, high-throughput, low-loss, real-time on-line, high-sensitivity mass spectrometry method.With the wide application of atmospheric mass spectrometry, rapid analysis of substances has become extremely important.In this paper, a new technique of microwave plasma torch ionization mass spectrometry (MPT-MS) is used to analyze metal elements, and other applications such as food safety, criminal investigation, environmental analysis and so on are developed for direct analysis of organic matter by MPT-MS.The main content of this paper includes the following five aspects, the main content is 1: 1.The basic principles, methods and devices of several atmospheric pressure plasma techniques are introduced systematically. The typical applications of microwave plasma torch mass spectrometry in the fields of medicine, stone, food and environment are reviewed.Using a new type of microwave plasma torch quadrupole mass spectrometry (MPT-Q-MS) as the experimental platform, the performance of the quadrupole mass spectrometer was tested and the ionization mechanism of the ion source was analyzed.On this basis, different sampling methods for solid, liquid and gas samples have been developed.By using the characteristics of microwave plasma torch (MPT) soft ionization without ar background, a comparative experiment was carried out on a quadrupole mass spectrometer (Q-MS) and a linear ion trap mass spectrometer (LTQ-MS).According to the characteristics of Q-MS instrument, more than 20 kinds of metal elements were analyzed and studied, and the preliminary rules of metal elements in water quality on Q-MS instrument were obtained, but because Q-MS instrument had no series mass spectrometry function,In order to better analyze and study metal elements in water, LTQ-MS instrument was used to analyze metal elements in the mode of positive and negative ions.The results show that the detection limit for quantitative analysis of metal elements by the: Q-MS instrument can reach the same order of magnitude as that of commercial LTQ-MS instruments, and the mass spectra peaks of metal elements in Q-MS instruments are mainly [M], [MOH], [MO], and [M(NO3)a(H2O)b] a-1 in LTQ-MS instruments.The anion mode of LTQ-MS instrument is more suitable for quantitative analysis of metal elements in water than that of positive ion mode.In order to expand the application of MPT source, the high temperature thermal effect and ionization effect of MPT are combined.Without sample processing, aflatoxin in rice in food field was analyzed quickly by MPT-LTQ-MS. The results showed that the linear range of this method was 0.5-20 渭 g / L ~ (-1) and the linear range was 0.12 渭 g / L ~ (-1).It is found that MPT-LTQ-MS method can provide a rapid qualitative analysis method for criminal investigation.In order to further expand the application field of this method, the tetracycline in the honey of agricultural products is also detected. The tetracycline contents in the four kinds of marketable honey are all within the allowable range of the national standard.Therefore, this method provides a new mass spectrometry method for direct analysis of organic samples.The application of microwave plasma torch mass spectrometry is summarized, and its future development and application are prospected.
【学位授予单位】：东华理工大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：O657.63

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