ATMOSPHERIC PRESSURE INFRARED MALDI MASS SPECTROMETRY

我们的建议的主要目的是开发一种新的样品引入接口基质辅助激光/解吸（MALDI）质谱（MS），以实现不仅从根本上简化的样品处理系统，但也高通量分析。与在真空系统内形成离子的常规MALDI相比，将使用在正常大气压下产生离子的大气压（AP）红外（IR）MALDI离子源。最近使用紫外（UV）激光器证明的AP-MALDI显示出与传统MALDI相当的灵敏度，对激光能量的大耐受性，以及分析物离子的最小碎片。AP-UV-MALDI的缺点是分析物基质簇形成的可能性高。为了克服这个问题，我们将使用微型可调谐IR激光器，其也被证明产生比UV-MALDI显著更少的碎片。考虑到有机化合物在IR光谱范围内的优异吸收，该提议使得液体分离技术与MALDI质量分析仪的直接耦合成为可能，因此，在同一质量分析仪上具有用于液体分析的MALDI和电喷雾离子源两者的前景变得非常可行。拟议的商业应用：大气压IR-MALDI离子源可以作为传统离子源的最佳替代品，用于质谱仪与液体分离技术的接口以及离线分析。该方法在研究实验室、医院、工业和国防中具有许多生物和生物医学应用，其中利用蛋白质、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.