DURABLE GOLD-COATED FUSED-SILICA CAPILLARIES FOR USE IN ELECTROSPRAY MASS-SPECTROMETRY

A simple procedure for preparing gold-coated silica capillaries for us e in electrospray ionization mass spectrometry is described. The tip o f the capillary is mechanically tapered, to a fine point, and a thin f ilm of gold is vapor deposited on the outer surface following treatmen t with an organofunctional silane. The performance characteristics of these durable capillaries as continuous infusion sources are examined, and their utility in on-line capillary electrophoresis mass spectrome try is demonstrated.