Coupling capillary zone electrophoresis and continuous-flow fast atom bombardment mass spectrometry for the analysis of peptide mixtures.

Abstract Combined capillary zone electrophoresis (CZE)—continuous-flow fast atom bombardment (CF-FAB) mass spectometry is described for the analysis of mixtures of peptides. A 90 cm × 50 μm I.D. fused-silica capillary column was used for electrophoretic separations and was connected to the CF-FAB probe via an interface which allows a total flow into the mass spectrometer of about 5 μl/min. Solutions of peptides were pneumatically loaded onto the CZE capillary, providing sample amounts of 0.1–20 pmol. The magnetic mass spectrometer was scanned over the desired mass range, usually between m/z 500 and 2500. Results are shown for separation and analysis of mixtures of synthetic peptides and also for protease digests of recombinant human growth hormone and horse heart cytochrome c .