Time-of-flight mass spectrometry of biomolecules using particle and laser induced desorption

基因技术的巨大发展，以及包括人类在内的各种生物基因组序列的完成，为快速和灵敏地确定蛋白质的特性和功能提供了前所未有的机会。在这一蛋白质组学领域，质谱学发挥着举足轻重的作用，这是由于该领域同样戏剧性的发展，其中许多是在物理实验室。在80年代后期，两种新的电离技术--基质辅助激光解吸电离(MALDI)和电喷雾电离(ESI)的发明在很大程度上克服了有限的质量范围和灵敏度。2002年诺贝尔化学奖就是因为这些进展而获奖的。 我们研究的广泛目标是研究、开发和应用大分子，特别是生物分子的质谱学方法。我们的实验室首次展示了正交注射MALDI TOF和相应的使用四极杆/TOF构型的MS/MS的应用，并已成为蛋白质组学研究的标准技术。该项目的重点是研究激光解吸和粒子解吸大分子的物理机制，并开发改进的生物组织质量选择成像方法。最近在分析MALDI产生的离子方面的许多改进，如延迟提取和正交注入，都严重依赖于对射出动力学的了解，无论有没有引出场，我们建议继续使用轴向和正交注入TOF仪器进行此类研究。

The dramatic developments in gene technology, and the completion of genome sequences for a variety of organisms, including humans, provide unprecedented opportunities for rapid and sensitive determination of the identity and function of proteins. In this field of proteomics, mass spectrometry plays a pivotal role, due to similarly dramatic developments in this field, many of them in physics laboratories. In the late 80s, limited accessible mass range and sensitivity were largely overcome by the invention of two new ionization techniques, matrix-assisted laser desorption/ionization (MALDI), and electrospray ionization (ESI). The 2002 Nobel prize in Chemistry was awarded in part for these developments. The broad objectives of our research are to study, develop, and apply methods of mass spectrometry for large molecules, particularly biomolecules. Orthogonal-injection MALDI TOF and the corresponding application of MS/MS using a quadrupole/TOF geometry, were first demonstrated in our laboratory, and have become standard techniques in proteomics research. The particular focus of this project is to study the physical mechanisms involved in the desorption of large molecules by laser and particle desorption and to develop improved methods for mass selected imaging of biological tissue. Many of the recent improvements in analyzing ions produced by MALDI, such as delayed extraction and orthogonal-injection depend critically on knowledge of the ejection dynamics, with and without an extraction field, and we propose to continue our work on such studies using both axial and orthogonal injection TOF instruments.