Matrix-assisted UV laser desorption of biopolymers: influence of the interactions in the target

Laboratoire de physique et chimie biomoléculaire, CNRS URA 198, Institut Curie et université Pierre-et Marie-Curie, 11, rue Pierre-et-Marie-Curie, 75231 Paris Cedex 05, France.

Abstract

The influence of the nature of the matrix and of the macroscopic structure of the target on the MALD spectra of proteins has been systematically studied for matrices such as 2,5-dihydroxybenzoic acid, 3,5-dimethoxy-4-hydroxycinnamic acid, 3-hydroxy-4-methoxycinnamic acid and α-cyano-4-hydroxycinnamic acid. Only 3,5-dimethoxy-4-hydroxycinnamic has been found to give homogeneous targets and reproducible spectra. The neutral contribution to the protein molecular and cluster peaks, which depends on the the laser fluence and on the mass of the protein, also strongly depends on the nature of the matrix.