Fast atom bombardment mass spectrometric analysis of arginine-containing neuropeptides.

A new procedure using fast atom bombardment mass spectrometry for the determination of arginine residues in neuropeptides is described. The technique is based on the modification of the arginine side-group with 1,2-cyclohexanedione. This novel procedure may have a potential use in the study of neuropeptides and their processing and degrading enzymes.