Microbore high-performance liquid chromatography-mass spectrometry for the analysis of proteolytic digests by continuous-flow fast-atom bombardment mass spectrometry.

Microbore high-performance liquid chromatographic (HPLC) techniques have been combined with fast atom bombardment mass spectrometry (FAB-MS) for the mass-specific detection of mixtures of peptides produced by proteolytic hydrolysis of proteins. The continuous-flow FAB interface has been utilized for direct coupling of the microbore HPLC system and the mass spectrometer. Conditions are reported for the effective separation of 100 pmol of peptides at flow-rates of 5 microliters/min with acetonitrile gradients and 1-mm I.D. C8 columns. A comparison is also made between columns of 5 and 25 cm lengths for the separation of peptide mixtures. Data are presented for the separation of peptides on a slurry-packed C18 fused-silica capillary column with the continuous-flow HPLC-FAB-MS interface at flow-rates of 3 microliters/min.