ATMOSPHERIC PRESSURE INFRARED MALDI MASS SPECTROMETRY

我们建议的主要目的是开发一种新的基质辅助激光/解吸（MALDI）质谱（MS）样品导入界面，不仅可以彻底简化样品处理系统，还可以实现高通量分析。与在真空系统中形成离子的传统MALDI相比，将使用常压（AP）红外（IR） MALDI离子源，其中离子在正常大气压下产生。AP-MALDI最近使用紫外（UV）激光进行了演示，显示出与传统MALDI相当的灵敏度，对激光能量有很大的耐受性，并且分析物离子的碎裂最小。AP-UV-MALDI的一个缺点是分析物基质团簇的形成概率很高。为了克服这个问题，我们将使用一种微型可调谐lR激光器，它也被证明比UV-MALDI产生更少的碎片。鉴于在lR光谱范围内有机化合物的良好吸收，该提议使液体分离技术与MALDI质谱分析仪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离子源可以是传统离子源的最佳替代方案，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 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.