Influence of amino acid and N-terminal protection residue structures on peptide p-nitroanilide adsorption on polystyrene-based support.

Polystyrene-based support Bio-Beads® SM-2 was employed for desalting peptide-p-nitroanilides from Oxone®. Neither tosyl, 9-fluorenyl(methoxycarbonyl), p-nitroanilide groups nor indolyl or p-hydroxyphenyl side-chains of Trp and Tyr ensured an efficient adsorption of peptide-p-nitroanilides onto Bio-Beads® SM-2. Only unsubstituted phenyl-containing protection groups (carbobenzoxy or benzoyl) and Phe residues provided the adsorption of peptides on Bio-Beads® SM-2 and their efficient desalting. This support is well suitable for multiple parallel phenyl group-containing peptide derivative separations and high-throughput screenings.