Laser desorption mass spectrometry.

The examples presented indicate that MALDI-MS is a useful tool for evaluating the progress of peptide synthesis at all the necessary levels: automated assembly, cleavage and deprotection chemistries, RP-HPLC analyses and purifications, and structural validation of the final product. The technique, if judiciously applied, permits the evaluation of complex peptide mixtures and often provides a semiquantitative overview. We have found that the availability of this method has enabled the provision of high-quality peptide reagents for use in the local research environment. The integration of this methodology into our peptide synthesis facility has also enabled and encouraged us to undertake more challenging synthetic problems such as phosphopeptide synthesis, peptide cyclizations, and peptide modification chemistries that would not ordinarily be offered if the laboratory lacked this technology. MALDI-MS is one of the more versatile and readily integrable mass spectrometric methods that can be incorporated into the average peptide synthesis laboratory.