Protein-Surface Interactions: MALDI MS Based Fundamental Studies and Bioselective Probe Development

德克萨斯大学阿灵顿分校的加里·金塞尔（Gary Kinsel）教授在分析和表面化学项目的支持下，系统地探索蛋白质与表面相互作用作为基质辅助激光解吸/电离质谱（MALDI）性能的基本决定因素。PI寻求了解表面特性如何影响MALDI以及如何使用这些特性来增强其生物分析效用。 通过PI先前的CAREER奖，已经定量证明了表面效应对肽和蛋白质的MALDI信号的重要性，并得出结论，MALDI的检测限（LOD）至少部分受蛋白质-表面相互作用的调节。在与Richard Timmons教授的合作中，PI将检查通过射频等离子体聚合产生的各种无污染表面，以进一步降低MALDI LOD。 从CAREER Award结果得出的第二个结论是，表面化学可用于选择性地调节肽和蛋白质信号。在这里，金属浸渍的表面将探索作为一种手段，选择性地分离磷酸肽，这是目前蛋白质组学社区的极大兴趣。他们还建议使用表面电荷作为浓缩分析物的手段;表面电荷可以作为pH值的函数而变化，这将允许选择特定的pI级分进行浓缩并随后释放用于MALDI分析。MALDI是肽和聚合物测序的重要方法，但影响灵敏度和响应的基本过程和因素尚未完全了解。 这项工作将通过提高MALDI分析的灵敏度和特异性来推进分析技术的发展。它还将进一步发展材料科学和分析化学之间的接口，通过展示如何将专门定制的材料和表面快速集成到分析方法中。最后，它将继续开发研究蛋白质-表面相互作用的新工具，这在许多领域都很重要，例如，在理解细胞表面生物学和开发生物传感器方面。 PI已经为进一步开发MALDI MS技术的应用（包括药物发现和疾病生物分析检测）提供了工业支持和正在进行的工业合作，证明了拟议计划的实际重要性。

Professor Gary Kinsel of the University of Texas Arlington is supported by the Analytical and Surface Chemistry Program to systematically explore protein-surface interactions as a fundamental determinant of the performance of matrix assisted laser-desorption/ionization mass spectrometry (MALDI). The PI seeks an understanding of how surface properties affect MALDI and how these properties can be used to enhance its bioanalytical utility. Through the PI's previous CAREER Award, the importance of surface effects on MALDI signal for peptides and proteins has been quantitatively demonstrated, and has lead to the conclusion that the limit of detection (LOD) for MALDI is at least in part regulated by protein-surface interactions. In collaboration with Prof. Richard Timmons, the PI will examine a variety of non-fouling surfaces produced by rf plasma polymerization in an effort to further lower the MALDI LOD. A second conclusion drawn from the CAREER Award results is that surface chemistry can be used to selectively modulate peptide and protein signals. Here, metal impregnated surfaces will be explored as a means to selectively isolate phosphopeptides, which are currently of great interest in the proteomics community. They also propose to use surface charge as a means to concentrate analytes; surface charge can be varied as a function of pH, which will allow for the selection of specific pI fractions to be concentrated and later released for MALDI analysis.MALDI is an important approach for the sequencing of peptides and polymers, but the fundamental processes and factors that affect sensitivity and response are not fully understood. This work will advance the state of the analytical art by improving sensitivity and specificity in MALDI analyses. It will also further develop the interface between materials science and analytical chemistry, by showing how specifically tailored materials and surfaces can be rapidly integrated into analytical methods. Finally, it will continue to develop new tools for the study of protein-surface interactions, which are important in many areas, for example, in the understanding of cell surface biology and the development of biosensors. The practical importance of the proposed program is demonstrated by the industrial support and ongoing industrial collaborations that the PI already has in place for the further development of MALDI MS technology for applications including drug discovery and bioanalytical testing for disease.