Coaxial continuous flow fast atom bombardment in conjunction with tandem mass spectrometry for the analysis of biomolecules

Abstract
The capability of interfacing coaxial continuous flow fast atom bombardment (CF-FAB) with tandem mass spectrometry (MS/MS) is demonstrated. The goal of this research is to demonstrate the ability of obtaining on-the-fly (i.e. chromatographic real time) MS/MS spectra of biomolecules and to demonstrate the feasibility of using open tubular CF-FAB as a means of introducing and maintaining a constant flux of analyte into the mass spectrometer over long periods of time. On-the-fly MS/MS spectra of a tripeptide, Met-Leu-Phe, were obtained on a 220-pg injection and a 22-pg injection. With a total acquisition time of 2 s, fragment ions resulting from common backbone cleavages were observed. With a 50 .mu.m i.d. packed microcapillary column, the separation of a mixture was obtained and the MS/MS spectra were acquired as the analytes were eluting from the column. Through the use of the coaxial CF-FAB interface to deliver a constant flow of analyte, MS/MS spectra of a variety of compounds, including peptides, sugars, fatty acids, phospholipids, and steroids, were obtained as well as an MS/MS/MS spectrum of a tetrapeptide.