A novel interface for on-line coupling of liquid capillary chromatography with matrix-assisted laser desorption/ionization detection

A novel interface has been developed which should allow the direct on-line coupling of liquid capillary chromatography with matrix-assisted laser deso rption/ionization (MALDI) mass spectrometry detection. The interface employ s continuous analyte/matrix co-crystallization onto a porous frit installed at a capillary end which is used as the target for MALDI, After separation , the analyte effluent is premixed with the MALDI matrix solution and intro duced into the interface. The analyte/matrix mixture is co-crystallized ont o the frit surface in the vacuum environment of the mass spectrometer, Cont inuous matrix/analyte crystallization and interface regeneration is accompl ished by a combination of solvent flushing and laser ablation, The memory e ffect is negligible over a dynamic range of ca, 200, Several applications, including analysis of small peptides and combination with gel permeation ch romatography (GPC), have indicated that the on-line MALDI interface does no t sacrifice chromatographic or mass spectral resolution, and have demonstra ted the possibility of a reliable LC-MALDI system. Copyright (C) 1999 John Wiley & Sons, Ltd.