Coupling of capillary zone electrophoresis and capillary liquid chromatography with coaxial continuous-flow fast atom bombardment tandem sector mass spectrometry.

The coaxial continuous-flow fast atom bombardment (FAB) system has proven to be very useful for interfacing capillary liquid chromatography and capillary zone electrophoresis (CZE) with sector mass spectrometry (MS). The interface can be used for the acquisition of both MS and MS-MS spectra from femtomole levels of non-volatile and/or thermally labile analytes while maintaining separation efficiencies of hundreds of thousands of plates. The use of coaxial fused-silica capillary columns to independently deliver the microcolumn effluent and the FAB matrix to the tip of the FAB probe offers the following advantages: the composition and flow-rates of the two liquid streams can be independently optimized; the FAB matrix does not effect the microcolumn separation process; peak broadening is minimized since the two liquid streams do not mix until they reach the tip of the FAB probe where ion desorption occurs; and, with CZE, active electrophoretic transport delivers the analytes directly to the FAB probe tip. These features combine to make this coaxial continuous flow fast atom bombardment interface particularly well suited for use with microcolumn separation methods.