Characterization of deamidated peptide variants by micro-preparative capillary electrophoresis and mass spectrometry.
Capillary electrophoresis (CE) was compared with reversed-phase liquid chromatography for its ability to separate native and deamidated peptides. CE is shown to provide superior resolution of these peptides due to its charge-based separation mechanism. Fraction collection performed using a standard CE instrument equipped with a 96-well plate permits subsequent characterization by nanospray mass spectrometric (MS) analysis. Additional in-depth analysis by MS/MS is able to provide the location of the deamidation site based on y-ion mass shifts of 1Da.
Gennaro
Lynn A
LA
Protein Analytical Chemistry, Genentech, Inc., South San Francisco, CA 94080, USA.
Salas-Solano
Oscar
O