Electrospray Mass Spectrometry and Multiple Sequence Analysis of Synthetic Peptide Libraries

The determination of the composition and purity of synthetic combinatorial libraries of free peptides requires analytical techniques that are especially suited for the challenging task of mixture analysis. Qualitative and semi-quantitive information on the composition of complex mixtures can be obtained by electrospray mass spectrometry with a maximum of reliability, accuracy, and fastness. Especially in combination with tandem mass spectrometry, contaminations with by-products (e.g., peptides with uncleaved side-chain protecting groups) can be easily revealed. Multiple sequence analysis based on Edman degradation allows a quantitative determination of the composition of libraries as well as the determination of coupling efficiencies during the synthesis of a library.