Atmospheric Pressure Infrared MALDI Mass Spectrometry

本文的主要目的是开发一种新的接口，用于使用常压（AP）红外（IR）基质辅助激光解吸/电离（MALDI）方法将液体分离技术在线耦合到质谱仪（MS）上。与传统MALDI相反，离子是在真空系统中形成的。在AP MALDI中，它们是在正常大气压下产生的。AP MALDI首先使用紫外（UV）激光进行演示，随后进行商业化。它的灵敏度与传统的MALDI相当，对激光能量有很大的耐受性，分析物离子的碎片化最小。AP MALDI与离子阱mas光谱仪接口，为MALDI分析带来了独特的串联质谱（或MS/MS）能力。由于AP UV-MALDI主要使用固体有机基质，它像传统的UV-MALDI通常只允许离线分析。红外激光的使用将允许人们使用大量的基质进行质谱分析，包括液体基质。鉴于AP IR-MALDI对红外光谱范围内有机化合物的良好吸收，使得液体分离技术与质谱的直接耦合成为可能，因此，在同一台质谱分析仪上同时使用MALDI和电喷雾离子源进行液体分析的前景变得非常可行。建议的商业应用：大气压IR-MALDI用于连接质谱与液体分离技术以及离线分析。该方法在研究实验室，医院，工业和国防中有许多生物和生物医学应用，其中使用了蛋白质，肽，DNA和RNA的分析。SESI将该方法商业化是直截了当的。

The main purpose of this proposal is to develop a novel interface for on- line coupling of liquid separation techniques to a mass spectrometer (MS) using an atmospheric pressure (AP) infrared (IR) matrix-assisted laser desorption/ionization (MALDI) method. In contrast to conventional MALDI where ions are formed inside a vacuum system. In AP MALDI they are produced at normal atmospheric pressure. AP MALDI was first demonstrated and later commercialized using an ultraviolet (UV) laser. It showed sensitivity comparable to that of conventional MALDI, a large tolerance to the laser energy, and minimal fragmentation of analyte ions. AP MALDI interfaced with an ion trap mas spectrometer brings unique capability off tandem MS (or MS/MS) to MALDI analysis. Since AP UV-MALDI uses mostly solid organic matrices it like conventional UV- MALDI usually allows off-line analysis only. The use of an IR laser will allow one to use significantly larger number of matrices for MS analysis including liquid ones. Given excellent absorption or organic compounds in the IR spectral range the AP IR-MALDI makes possible direct coupling of liquid separation techniques =to MS, thus, the perspective of having both MALDI and electrospray ion sources for liquid analysis on the same mass analyzer becomes very feasible. PROPOSED COMMERCIAL APPLICATIONS: Atmospheric Pressure IR-MALDI for interfacing mass spectrometers to liquid separation techniques as well as for off-line analysis. This method has many biological and biomedical applications in research labs, hospitals, industry, and defense where analysis of proteins, peptides, DNA & RNA is utilized. Commercialization of the method by SESI is straightforward.