Abstract

The detection, identification, and analysis of biological materials in "real time" is of significant current interest in a number of fields. As with chemical materials, mass spectrometry holds great promise for such applications. We are presently engaged in a study of approaches to mass spectrometric analysis of biological materials, utilizing laser desorption/vaporization/ionization in conjunction with Fourier transform mass spectrometry. In this presentation, we focus on laser desorption/ionization applied to peptides. Although laser desorption can generate mass spectra with reasonably abundant molecular ion for relatively small peptides in the pure state, use of matrix-enhanced desorption techniques facilitates greatly the generation of molecular ion, We demonstrate this using examples of 248 nm laser desorption mass spectra of polypeptides. The nature of the substrate from which ions are desorbed is found also to be an important factor in the desorption/fragmentation processes through a study of a range of metallic supports. Thermal conductivity of the substrate appears to be the key parameter.

© 1992 Optical Society of America