Pulsed Laser Desorption in Supersonic Beam Spectroscopy/ Mass Spectrometry

这个项目是在一般地区的分析和表面 化学以及激光光谱学和质量的子领域 光谱法 这项实验活动的主旨是 开发新的、高选择性的分析方法， 非挥发性的、热不稳定的分子，主要是生物学上的 有意思的 为了达到这个目的，中性分子是 从表面解吸到气相中， 通过超音速喷射膨胀冷却， 内在能量 一旦冷却，这些分子表现出相当大的 特征鲜明的电子光谱 这些尖锐的特征使得 共振双光子电离的高选择性应用 这些技术用于将这些分子用于随后的 通过飞行时间质谱分析。 这种激光解吸，超音速喷射膨胀， 共振双光子电离和质谱提供了一个 高灵敏度、高选择性的分析工具， 和对广谱样品的定量表征。 虽然这种混合方法将主要集中在 具有药学和临床意义的生物分子的分析 例如儿茶酚胺、吲哚胺和小多肽， 这项研究的结果预计将产生广泛的影响， 化学、生物和材料科学。

This project is in the general area of analytical and surface chemistry and in the subfields of laser spectroscopy and mass spectrometry. The thrust of this experimental activity is the development of new, highly selective methods of analysis for nonvolatile, thermally labile molecules, primarily biologically interesting ones. To accomplish this end, neutral molecules are desorbed from surfaces into the gas phase whereupon they are cooled through supersonic jet expansion which reduces their internal energy. Once cooled, these molecules exhibit quite sharp-featured electronic spectra. These sharp features enable the highly selective application of resonant two-photon ionization techniques which are used to ionize these molecules for subsequent analysis by time-of-flight mass spectrometry. This combination of laser desorption, supersonic jet expansion, resonant two-photon ionization, and mass spectrometry affords a sensitive, highly selective analytical tool for the qualitative and quantitative characterization of a broad spectrum of samples. Whereas this hybrid approach will be primarily focussed on the analysis of biomolecules of pharmaceutical and clinical interest such as catecholamines, indolamines, and small polypeptides, the results of this research are can be expected to impact broadly in the chemical, biological, and materials sciences.