Abstract:
A goal of our research is to develop multi-dimensional separations techniques that will allow us to increase chemical information content using mass spectrometry based proteomics. For example, we have combined off-line capillary electrophoresis (CE) with matrix assisted laser desorption/ionization (MALDI) - mass spectrometry (MS) to facilitate peptide identification and compositional information, viz. determining the number of basic amino acid residues in a peptide.1 We also developed a novel isoelectric point (pI) based separation device termed membrane separated wells for isoelectric focusing and trapping (MSWIFT) which allows for quick in-solution separations of ampholytes.2 In addition, we have used MSWIFT in combination with CE-MALDI-MS for rapid analysis of protein mixtures and mixtures of protein proteolytic digests. Lastly, we have combined CE-MALDI-MS and MSWIFT-CE-MALDI-MS with ion mobility-mass spectrometry (IM-MS) to enhance protein ID, determination of post-translational modification, and information content for applications of imaging mass spectrometry of lipid bilayers. This presentation will focus on analytical figures-of-merit for extensive hyphenation of analytical methodologies as well as presentation of results that underscore the utility of these experimental approaches.
References:
(1) Williams, B. J.; Russell, W. K.; Russell, D. H. Analytical Chemistry 2007, 79, 3850-3855.
(2) Lim, P.; North, R.; Vigh, G. Electrophoresis 2007, 28, 1851-1859.