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1.
梁晓东 《质谱学报》2002,23(4):234-234
回顾了质谱在新药研究中的一些应用 ,包括新药合成、化学结构确证、质量控制以及药物代谢物的鉴定等。综述了基质辅助激光解吸电离 \飞行时间质谱 ( Matrix-assistant laser desorption ionization time-of-flight mass spectrometry,MALDI/ TOFMS)、电喷雾电离质谱 ( Electrode spray ionization m ass spectrome-try,ESI-MS)等仪器及其联用技术在生物大分子药物研究 ,包括蛋白质组学、肽图谱、氨基酸序列、核苷酸分析等方面的进展 ,展望了质谱在未来生命科学中广阔的应用前景。  相似文献   

2.
综述了近 2 0年来富勒烯及其衍生物的质谱研究进展。概述了激光解吸飞行时间质谱 ( LD-TOFMS)、化学电离质谱 ( CIMS)、解吸化学电离质谱 ( DCIMS)、解吸电子轰击质谱 ( DEIMS)、电喷雾电离质谱 ( ESIMS)、傅立叶变换离子回旋共振质谱 ( FT-ICRMS)等质谱技术在富勒烯及其衍生物的表征、生成机理及结构研究、富勒烯气相离子化学及反应活性研究等中发挥的重要作用。由于 C60 等富勒烯及其衍生物的难挥发性及强紫外光吸收能力 ,L D-TOFMS特别适用于富勒烯及其衍生物的分析。结合其它技术 ,LD-TOFMS对富勒烯的生成机理及构型构象异构提供了大量的信息。各种质谱技术与离子化技术结合 ,揭示了不同富勒烯及富勒烯衍生物单分子的解离模式 ,证明了富勒烯的“超芳香性”和“超烯性”等各种反应活性  相似文献   

3.
Huang R  Yu Q  Li L  Lin Y  Hang W  He J  Huang B 《Mass spectrometry reviews》2011,30(6):1256-1268
This article reviews the development of and applications for high irradiance laser ionization orthogonal time-of-flight mass spectrometry (LI-O-TOFMS). LI-O-TOFMS has solved the bottleneck problems in traditional high irradiance laser ionization mass spectrometry, which allows the instrument to acquire explicit spectra with high resolution. A buffer-gas-assisted ion source effectively reduces the kinetic energy of the ions and suppresses the multiply charged ion interference. The pulse train data acquisition technique was applied to reduce the spectrum interference from multiply charged ions and polyatomic ions according to the temporal profiles of different ion packets in the repelling region. Relatively high laser irradiance (≥10(10) W/cm(2)) is preferable for achieving uniform relative sensitivities for different elements in the samples of different matrices. LI-O-TOFMS has been used in the standardless, semiquantitative analysis of solids, which is proved to be a fast and convenient technique for solid sample analysis. By increasing the laser irradiance and reducing the buffer gas pressure, the determination of nonmetallic elements in solids can also be achieved without losing spectral explicity. Recent applications, such as elemental analysis of a single egg cell and acquiring elemental, fragmental, and molecular information of chemicals, were given to demonstrate the potential of the new technique. All of these results reveal that LI-O-TOFMS is an advanced tool in the elemental analysis of solids in terms of modern mass spectrometry.  相似文献   

4.
近年来,挥发性有机物(VOCs)快速、在线分析的应用需求促进了各类VOCs在线分析质谱仪的发展。本研究自行研制基于膜进样技术的小型紫外光电离飞行时间质谱仪,并阐述设计原理、性能表征及其对工作场所VOCs的检测应用。仪器采用聚二甲基硅氧烷(PDMS)作为进样界面,既保证了仪器的真空,又起到富集VOCs并降低检出限的作用。电离源使用发射10.6 eV光子的氪灯作为光源,可电离低于10.6 eV电离能的VOCs,并产生分子离子峰,这一特性便于谱图识别与高通量分析。飞行时间质量分析器采用小型化设计,总长度小于360 mm。结果表明,该仪器在m/z 170处全高半峰宽(FWHM)分辨率为2 000,苯、甲苯、对二甲苯的检出限在5×10-10~3×10-9 mol/mol之间。将该仪器用于工作场所中苯系物成分分析,取得了良好的靶向分析结果。  相似文献   

5.
An overview is given on pesticide-residue determination in environmental and food samples by liquid chromatography/mass spectrometry/mass spectrometry (LC/MS/MS). Pesticides comprise a large number of substances that belong to many completely different chemical groups, the only common characteristic is that they are effective against pests. They still constitute a challenge in MS because there is no collective pathway for fragmentation. A brief introduction to the theory of tandem MS permits a discussion of which parameters influence the ionization efficiency when the ions are subjected to different actions. Emphasis is placed on the different tandem MS instruments: triple and ion-trap quadrupoles, and hybrid quadrupole time-of-flight (Q-TOF), including advantages and drawbacks, typical detection limits, and ion signals at low concentrations. The instrumental setup, as well as LC and mass spectrometric experimental conditions, must be carefully selected to increase the performance of the analytical system. The capacity of each instrument to provide useful data for the identification of pesticides, and the possibility to obtain structural information for the identification of target and non-target compounds, are discussed. Finally, sample preparation techniques and examples of applications are debated to reveal the potential of the current state-of-the-art technology, and to further promote the usefulness of tandem MS.  相似文献   

6.
The design and performance of two orthogonal extraction time-of-flight mass spectrometers are reported that were adapted to existing focused ion beam microscopes for secondary ion mass spectrometry. The performances of these designs were compared to that of a prototype previously described by our group. The differences include newly designed transfer ion optics and in the use of a larger microscope chamber. The two new prototypes allow a mass resolving power of either 600 Th/Th (compact design) or 3000 Th/Th (high resolution design) while simultaneously achieving a lateral spatial resolution of less than 50 nm. The spectrometers and their performance (effective ion yield, mass resolving power, lateral, and depth resolution) are described and compared. Additionally, example applications are presented with multivariate statistical methods to visualize the data sets. Both time-of-flight mass analyzers use orthogonal extraction which avoids the need to pulse the primary ion beam, and the of use monoisotopic gallium to preserve the mass resolution. The goal of the design was a cost-effective accessory to augment typical focused ion beam-scanning electron microscopy applications as an alternative to the cost of a dedicated secondary ion mass spectrometer. The modified instrument allows excellent non destructive imaging and easy sample access, and benefits from the presence of complementary non destructive analytical and imaging techniques that exploit the presence of an electron microscope.  相似文献   

7.
Microfabrication of analytical devices is currently of growing interest and many microfabricated instruments have also entered the field of mass spectrometry (MS). Various (atmospheric pressure) ion sources as well as mass analyzers have been developed exploiting microfabrication techniques. The most common approach thus far has been the miniaturization of the electrospray ion source and its integration with various separation and sampling units. Other ionization techniques, mainly atmospheric pressure chemical ionization and photoionization, have also been subject to miniaturization, though they have not attracted as much attention. Likewise, all common types of mass analyzers have been realized by microfabrication and, in most cases, successfully applied to MS analysis in conjunction with on‐chip ionization. This review summarizes the latest achievements in the field of microfabricated ion sources and mass analyzers. Representative applications are reviewed focusing on the development of fully microfabricated systems where ion sources or analyzers are integrated with microfluidic separation devices or microfabricated pums and detectors, respectively. Also the main microfabrication methods, with their possibilities and constraints, are briefly discussed together with the most commonly used materials. © 2009 Wiley Periodicals, Inc., Mass Spec Rev 29:351‐391, 2010  相似文献   

8.
刘成园  潘洋 《质谱学报》2021,42(4):514-531
原位质谱技术具有原位、微量、实时、在线、无需样品预处理的特点.近年来,基于不同电离原理开发的原位离子化技术相继问世.原位光电离是一种基于大气压光电离的离子化技术,具有无电离极性歧视、电离碎片少以及抗基质效应强等优点.原位光电离通常需引入掺杂剂以增强离子化效率,待测物既可通过光致直接电离,亦可通过光电离诱导的离子分子反应...  相似文献   

9.
何妙洪  杭纬  黄本立 《质谱学报》2014,35(3):193-288
对于传统的高功率激光质谱存在的关键问题,如离子动能分散、多价离子和多原子离子干扰、基体效应和分馏效应等,高功率激光电离飞行时间质谱(LI-TOF MS)通过仪器结构设计及实验条件的优化等可以很好地解决。目前,LI-TOF MS的应用包括地质和金属样品中元素的定性和无标样半定量分析、非金属元素的测定、元素表面成像分析和薄层的深度剖析、液体残渣分析、复杂生物材料中元素组成的确定,甚至对于有机金属化合物也可以同时获得分子、碎片和元素信息。本工作综述了LI-TOF MS技术的发展历程,分析了其在不同领域中的优势,并对其应用领域拓展的新方向和仪器的改进目标进行了展望。  相似文献   

10.
傅里叶变换离子回旋共振质谱的最新进展和展望   总被引:1,自引:0,他引:1  
对傅里叶变换离子回旋共振(FT-ICR)质谱的基本原理进行了简要介绍,从离子回旋频率、回旋半径、离子速度、离子能量等几个方面阐明其基本概念,阐述了离子激发、检测原理.对离子同旋共振质谱与近年来新兴的常压离子化技术联用的最新进展进行了评述,对其发展趋势进行展望.由于常压离子化技术能够将复杂样品进行直接离子化,无需样品预处理或只需少量样品处理过程,常压离子化方法与FT-ICR质谱的联用必将拓宽其应用领域并成为质谱技术研究的新热点.  相似文献   

11.
This review article will give an up-to-date and exhaustive overview on the efficient use of electron ionization (EI) to couple liquid chromatography and mass spectrometry (LC-MS) with an innovative interface called Direct-EI. EI is based on the gas-phase ionization of the analytes, and it is suitable for many applications in a wide range of LC-amenable compounds. In addition, thanks to its operating principles, it prevents unwelcome matrix effects (ME). In fact, although atmospheric pressure ionization (API) methodologies have boosted the use of LC-MS, the related analytical methods are sometime affected by inaccurate quantitative results, due to unavoidable and unpredictable ME. In addition, API's soft ionization spectra always demand for costly and complex tandem mass spectrometry (MS/MS) instruments, which are essential to acquire an "information-rich" spectrum and to obtain accurate quantitative information. In EI a one-stage analyzer is sufficient for a qualitative investigation and MS/MS detection is only used to improve sensitivity and to cut chemical noise. The technology illustrated here provides a robust and straightforward access to classical, well-characterized EI data for a variety of LC applications, and readily interpretable spectra for a wide range of areas of research. The Direct-EI interface can represent the basis for a forthcoming universal LC-MS detector for small molecules.  相似文献   

12.
综述了基质辅助激光解吸电离飞行时间质谱(MALDI-TOF-MS)的基本原理,基质选择和样品制备方法、分析离子化试剂等因素对实验结果的影响,以及造成质量歧视的原因。并阐述了MALDI技术在确定聚合物相对分子质量分布,聚合物末端基团,共聚物组成和推断反应及降解机理上的应用。  相似文献   

13.
高立本  董玉杰 《质谱学报》2017,38(3):349-360
质谱技术发展初期主要用于与核工业相关的无机同位素丰度的测定,随着核工业的兴起与发展,质谱技术被广泛应用于核燃料与核材料中杂质分析、核燃料燃耗测定以及核素分析等领域。本工作从质谱技术用于高温气冷堆运行中产生的氚检测、乏燃料中痕量钚(Pu)和镎(Np)测定以及乏燃料中14C测定的原理及应用、研究方法的优缺点三方面展开论述,阐述了用于高温气冷堆及其乏燃料中核素分析方面的气体同位素质谱仪(GIMS)、电感耦合等离子体质谱仪(ICP-MS)、激光共振电离质谱仪(LRIMS)以及加速器质谱仪(AMS)的研制及应用现状,分析了仪器本身及其应用方面存在的问题及发展趋势,讨论了未来相关质谱技术的发展方向,并提出可能的解决方案。为了使质谱技术能够更加有效地应用于高温气冷堆的研究,迫切需要发展体积小、结构简单、便于操作的智能化仪器。  相似文献   

14.
季怡萍  张红明 《质谱学报》2006,27(Z1):81-82
Different structural anthracene oligomers containing acetylene were characterized by laser desorption ionization time-of-flight mass spectrometry (LDI-TOF-MS). The samples were dissolved in chloroform and the data were recorded by positive ion mode. LDI-TOF-MS is very effective for the analysis of the novel meatl tetraazaporphrins including tetra-(naphthalene)-tetraazaporphyrin.  相似文献   

15.
I. Introduction 88 II. Cap-EI Interface 90 A. Interface Performance 92 III. Direct-EI Interface 93 A. Interface Performance 97 IV. Conclusions 103 Acknowledgments 103 References 103 --Two recent approaches for coupling capillary scale liquid chromatography and electron ionization mass spectrometry are reviewed and discussed. The first one, Cap-EI, is the latest evolution of the micro-scale particle beam interface, in which the nebulizer has been optimized to overcome the limitations of the former approach, in terms of sensitivity and linearity. It can be easily hosted in pre-existing instruments without major modifications and can use helium and the less-expensive nitrogen to generate library-matchable electron ionization spectra. The second one is a miniaturized interface for nano- and micro-HPLC, in which the interfacing process takes place into a suitably modified ion source. Because the eluate from the column is completely transferred into the ion source for ionization, superior sensitivity, linearity, and reproducibility are obtained. No signs of chemical ionization are observed at flow rates up to 1.5 microL/min. These two interfaces demonstrate that electron ionization can be successfully used for the analysis of small-medium molecules of various polarities, and also at the trace level. The possibility to record library-matchable electron ionization spectra offers the analyst a powerful tool that can be particularly useful in real-world applications.Copyright 2001 John Wiley & Sons, Inc.  相似文献   

16.
17.
本工作介绍了实验室自制的热电离飞行时间质谱仪(TI-TOF-MS)的基本结构、仪器运行参数和性能特点等。离子源产生的离子在推斥电压作用下进入聚焦透镜,然后进入垂直引入反射式的飞行时间质量分析器,最后到达检测器。信号通过数据采集卡处理后传输给计算机,采用编写的LabVIEW软件采集信号和处理数据。结果表明:仪器可测量的质量范围为m/z 6~320,在m/z 208位置的质量分辨率可达2000,2 h质量稳定性为7.76×10-5,测量207Pb/206Pb、207Pb/206Pb和207Pb/206Pb同位素比值的精密度分别为0.85%、0.27%和0.55%。该仪器在研究热电离离子源电离行为、同位素比值测定和多原子离子信号监测等方面具有广泛的应用前景。  相似文献   

18.
何坚  余泉  杭纬  黄本立 《质谱学报》2010,31(5):264-269
介绍了两台自行研制的激光溅射离子源垂直引入式飞行时间质谱仪(LAI-oa-TOFMS),相比于其他固体样品直接分析法,该仪器具有样品预处理简单、样品更换速度快(数分钟)、可进行微区分析、谱图干扰峰少和绝对灵敏度高(10-15g级)等众多优点。两台质谱仪的最佳质量分辨率分别达到7 000和4 000(FWHM)。重点对比分析了不同样品的电离方式和离子传输系统对仪器性能的影响。  相似文献   

19.
杨芃原  朱晨鑫  刘凯  刘颖超  李顺祥  赵和玉  贾滨 《质谱学报》2020,41(2):101-109,I0003
四极杆和飞行时间质谱是液相色谱-质谱(LC/MS)、三重四极杆质谱(QQQ)和四极杆-飞行时间质谱(Q TOF)等质谱仪器中必备的核心部件,也是我国亟待研发的国产化仪器。目前,国内对质谱仪器的研制热情日益高涨,得到了国家相关部门的高度认可和广大研发人员的积极响应。本综述基于作者课题组多年的研制经验,从质谱仪器研发的角度介绍实现离子光学系统和电子学系统的技术原理。首先回顾四极杆的基本原理;然后着重讨论加工和装配精度对提高四极杆分辨率的重要性,以及四极杆尺寸选择对射频电压控制的影响;最后重点介绍四极杆串联振荡电子学系统以及在系统中起关键作用的阻抗匹配,希望能为质谱仪器研制提供参考。  相似文献   

20.
应用激光解吸飞行时间质谱对含有不同金属的五种四(萘)并四氮杂卟啉配合物进行表征。样品溶解在二甲基亚砜中,以正离子方式记录谱图,结果发现除产生一个失去氯原子的分子离子峰外,没有任何碎片峰。激光解吸电离飞行时间质谱是表征四(萘)并四氮杂卟啉配合物的有效方法。  相似文献   

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