The product is a slide coated with silica colloidal crystals to combine protein electrophoresis with matrix- assisted laser desorption/ionization mass spectrometry (MALDI-MS) detection, giving superior performance in both. The Phase II proposal will be to develop an instrument for facile application of the slide in proteomics of intat glycoproteins. This proposal is a collaboration between the Wirth group at Purdue, who have developed new media for protein separations that can be coupled with MALDI-MS, and LI-COR, Biosciences, whose core competency is the commercialization of instruments for bioanalysis. Preliminary results using a modified silica colloidal crystalline surface as a MALDI-MS substrate show a reduction in adduct formation, and an increase in mass resolution. Additionally, the silica colloidal crystalline surface is a medium to separate proteins using isoelectric focusing. Combining the ability to both separate and detect proteins using a single thin layer crystalline surface that enables high resolution protein separation and improved MALDI-MS detection will expand the utility of using MALDI-MS for identifying novel biomarkers based on post translational modifications. The phase I specific aims are to optimize the silica crystal propertie, to characterize the applicable molecular weight range, to study the enhanced resolution and the reduction in adduct formation as a direct result of using this substrate, and to combine protein separation techniques with MALDI-MS detection on a single silica colloidal crystalline surface.
This project focuses on developing a glass slide coated with silica colloidal crystals that can serve as both an electrophoretic separation medium, and an improved matrix- assisted laser desorption/ionization mass spectrometry (MALDI-MS) target surface. The crystalline surface integrates the methods of separating proteins by isoelectric focusing with MALDI-MS detection, producing a system that has both improved capabilities and improved peak resolution. Advances in MALDI-MS detection will aid in the analysis of post-translational modifications and the discovery of novel biomarkers.