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

Publisher Website
Google Scholar
Abstract
A novel interface has been developed which should allow the direct on‐line coupling of liquid capillary chromatography with matrix‐assisted laser desorption/ionization (MALDI) mass spectrometry detection. The interface employs 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 introduced into the interface. The analyte/matrix mixture is co‐crystallized onto the frit surface in the vacuum environment of the mass spectrometer. Continuous matrix/analyte crystallization and interface regeneration is accomplished by a combination of solvent flushing and laser ablation. The memory effect is negligible over a dynamic range of ca. 200. Several applications, including analysis of small peptides and combination with gel permeation chromatography (GPC), have indicated that the on‐line MALDI interface does not sacrifice chromatographic or mass spectral resolution, and have demonstrated the possibility of a reliable LC‐MALDI system. Copyright © 1999 John Wiley & Sons, Ltd.