This Technical Note describes the peptide hydrolysis procedures that lead to successful determinations of amino acid composition using AAA-Direct. Results for the amino analysis of two peptides, Melanocyte Stimulating Hormone (MSH) and Luteinizing Hormone-Releasing Hormone (LH-RH), using both hydrochloric acid and methanesulfonic acid (MSA) as hydrolyzing reagents are presented to demonstrate the performance of this method.
This application note shows that AAA-Direct can be used to determine peptides with lysine hydroxylation. All common amino acids, including hydroxylysine (Hyl), were separated by AAA-Direct, and the presence or absence of Hyl in the fractions confirmed peak identities. The techniques described in this application note show several ways that peptides can be evaluated for identity and purity, how peptides can be desalted, and how much desalting is needed for successful AAADirect amino acid analysis.
