An interface system between planar gel electrophoresis and mass spectrometry is described that includes a means of rapid electrophoretic gel disruption, concentration of extracted sample in a pre-column, and transfer of the sample molecules to the continuous flow FAB source of a mass spectrometer. Spatial resolution achieved on the surface of the gel is on the order of 2 mm diameter for a spot, and 4 mm2for a band. Sensitivities to 50 picomoles have been demonstrated for the analysis of small peptides with continuous-flow fast atom bombardment mass spectrometry.