ATMOSPHERIC PRESSURE INFRARED MALDI MASS SPECTROMETRY

我们建议的主要目的是开发一种新型的基质辅助激光解吸(MALDI)质谱仪的进样接口，不仅可以从根本上简化样品处理系统，还可以实现高通量分析。将使用常压(AP)红外(IR)MALDI离子源，其中离子在常压下产生，而传统的MALDI离子源中的离子在真空系统中形成。AP-MALDI最近使用紫外(UV)激光展示了与传统MALDI相当的灵敏度，对激光能量的巨大耐受性，以及分析物离子的最小碎裂。AP-UV-MALDI的一个缺点是分析物-基质簇的形成概率很高。为了克服这个问题，我们将使用一种微型的可调谐LR激光器，它产生的碎裂比UV-MALDI要小得多。鉴于有机化合物在LR光谱范围内的良好吸收，该建议使液体分离技术与MALDI质量分析仪直接耦合成为可能，因此，在同一质量分析仪上同时使用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：常压IR-MALDI离子源可作为传统离子源的最佳替代方案，用于质谱仪与液体分离技术的接口以及离线分析。这种方法在研究实验室、医院、工业和国防中有许多生物和生物医学应用，其中使用蛋白质、多肽、DNA和RNA的分析。通过SESI将该方法商业化是很简单的。

The main purpose of our proposal is to develop a novel sample introduction interface to matrix-assisted laser/desorption (MALDI) mass spectrometry (MS) to achieve not only a radical simplification of the sample handling system but also high throughput analysis. An atmospheric pressure (AP) infrared (IR) MALDI ion source in which ions are produced at normal atmospheric pressure will be used in contrast to conventional MALDI where ions are formed inside a vacuum system. AP-MALDI demonstrated recently using ultraviolet (UV) lasers has shown sensitivity comparable to that of conventional MALDI, a large tolerance to the laser energy, and minimal fragmentation of analyte ions. A drawback of AP-UV-MALDI was the high probability of formation of the analyte-matrix clusters. To overcome this problem we will use a miniature tunable lR laser which has also been shown to produce significantly lesser fragmentation than UV-MALDI. Given the excellent absorption of organic compounds in the lR spectral range the proposal makes possible direct coupling of liquid separation techniques to MALDI mass analyzers, 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 ion source can be the best alternative to the traditional ion sources 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.