A comparative study of laser spray and electrospray

Abstract

A comparative study of electrospray and laser spray has been undertaken from various aspects. In general, laser spray gave stronger ion signals than electrospray, for solutions with the sample concentration of </=10(-5)M. For an aqueous solution of arginine, ion intensities of the cluster ions H(+)(arginine)(n) with larger n were observed by laser spray than by electrospray. This may be due to the enrichment of the sample concentration by the selective vaporization of the solvent from the meniscus of the sample solution effusing out of the stainless steel capillary by the laser irradiation. For an H(2)O/CH(3)OH (1:1, v/v) solution of 10(-5) M Arg-Lys-Arg-Ala-Arg-Lys-Glu, laser spray gave stronger ion signals than electrospray while the most highly charged ion observed was [M + 4H](4+) for laser spray and [M + 5H](5+) for electrospray. Laser spray was found to be the most suitable for the analyses of aqueous solutions. Copyright 2000 John Wiley & Sons, Ltd.