Gas-phase hydrolysis of proteins and peptides

A simplified gas-phase hydrolysis procedure for proteins and peptides is described. The apparatus consists of a glass vacuum desiccator, a ceramic plate, and a Teflon ring. The method was shown to give reproducible compositions for hydrolysis of human serum albumin and microanalysis of alpha-melanocyte stimulating hormone including the quantitation of as little as one residue of tryptophan. It minimizes sample handling and allows for the simultaneous hydrolysis of a large number of samples.