Ultramicroanalysis of peptide profiles in biological samples using MALDI mass spectrometry.

In the past few years, matrix-assisted laser desorption/ionization (MALDI) mass spectrometry has emerged as a powerful tool for the direct analysis of peptide profiles contained in single neuroendocrine cells, tissue biopsies, as well as in releasates (after a simple sample clean-up). These studies were performed in both invertebrate (the pond snail) and vertebrate (xenopus and rat) species. The present article provides an overview of these data with a special emphasis on the sample handling required for each application.