Complex Peptide Mixture Fractionation via Parallel Isoelectric Focusing for Direct LC-MS/MS Analysis (ASMS 2010)

Charge-based separation of peptides prior to LC-MS analysis has been hampered by long run times and the presence of components such as detergents and carrier ampholytes that interfere with MS (1). Cell Biosciences has developed a workflow using the digital ProteomeChip (dPC), that captures peptides in acrylamide gel plugs according to charge, with run times less than one hour (2,3) (figure 1). This workflow employs buffers and conditions that have been designed to be ìMS-friendly,î eliminating the need for postseparation sample clean-up and dramatically reducing artifacts introduced by the separation processes. Cell Biosciences ProteomeChips are available in three pH ranges: 3.5-4.5, 4.2-6.2 and 6.0-8.0, providing an overall pH range of 3.5-8.0.