Photodissociation for Ion Trap Mass Spectrometry

化学系的分析和表面化学项目将支持德克萨斯大学奥斯汀分校Jennifer Broadbelt教授的研究项目。Broadbelt教授在质谱领域的研究项目将包括在四极离子阱质谱仪中使用红外和紫外激光对离子进行光解离，以及使用新的化学衍生化方法来增加化学选择性或提高分子的吸收率。当离子受到红外或紫外光子照射时，离子吸收能量导致键断裂，从而形成诊断碎片离子。这些碎片模式提供了分子的“指纹”，从而可以自信地识别肽和其他生物学相关分子。光子的吸收对于这种分析方法的成功至关重要，因此分子的吸收率可以通过附加不同的化学基团来调节，称为“发色团”，以增强光子的吸收。该研究的目的是通过一系列衍生化策略通过附加发色团来提高目标分析物的光子吸收效率。Broadbelt教授和她的学生将在生物分子上添加化学基团，以促进气相中的光激活反应，例如在光激活时以特定位点、可预测的方式选择性地切割多肽骨干。所提出的工作对整个社会的潜在好处包括培训和教育未来的科学家，特别是在生物质谱领域，发展创新的基于激光的生物分子结构表征方法，以及实施新的离子激活策略，这些策略在许多领域的质谱分析中都很重要。从蛋白质组学到理解生物大分子相互作用的复杂性。

The Analytical and Surface Chemistry program in the Division of Chemistry will support the research program of Prof. Jennifer Broadbelt of the University of Texas at Austin. Prof. Broadbelt's research program in the area of mass spectrometry will involve the use of both infrared and ultraviolet lasers for photo dissociation of ions in a quadrupole ion trap mass spectrometer, along with novel chemical derivatization methods to add chemical selectivity or enhance absorptivities of molecules. Upon irradiation of ions with infrared or ultraviolet photons, the ions absorb energy that leads to bond cleavages, resulting in formation of diagnostic fragment ions. These fragmentation patterns provide a "fingerprint" of the molecules, thus allowing confident identification of peptides and other biologically relevant molecules. The absorption of photons is essential for the success of this analytical method, and thus the absorptivity of molecules can be modulated by attaching different chemical groups, termed "chromophores", that enhance the absorption of photons. The objective of the study is to increase the photon absorption efficiencies of targeted analytes by appending chromophores via an array of derivatization strategies. Prof. Broadbelt and her students will append chemical groups to biomolecules that promote photoactivated reactions in the gas phase, such as the selective cleavage of polypeptide backbones in a site-specific, predictable manner upon photoactivation. The potential benefits of the proposed work to society at large include the training and education of future scientists, especially in the area of biological mass spectrometry, the development of innovative laser-based methods for structural characterization of biological molecules, and implementation of new ion activation strategies that are expected to be important in mass spectrometric analysis in many areas, ranging from proteomics to understanding the complexities of interactions of biological macromolecules.