The Influence of Peptioe Structure on the Retention of Small Chain Peptides on Reverse Stationary Phases

Abstract

Several characteristic structural features of peptides were considered in a study on the retention of small chain peptides on C₈ and polystyrene-divinylbenzene reverse stationary phases. These include the effects of subunit nonpolar, polar, acidic, and basic side chains, the influence of the location (terminal or interior) of a nonpolar subunit in the peptide chain, effects of two or more nonpolar subunits and their location (terminal or interior) in the peptide chain, and the effect of two chiral centers and their location (terminal and/or interior) in the peptide chain. LC data, which were collected in an acidic, zwitterion pH, and basic mobile phase where possible, indicated that location of the side chains in the peptide relative to the terminal charge sites is also an important factor in determining peptide retention. Peptides with side chains containing acidic or basic groups were studied as a function of mobile phase pH. Whether these groups are ionized or not and their location relative to the terminal charged sites strongly influences peptide retention.