Reversed-phase preparative chromatography of [D-Ala1]-peptide T amide

[D-Ala1]peptide T amide is a metabolically stable and more potent analogue of peptide T, a proposed inhibitor of human immunodeficiency viral infectivity of human T-cell lymphocytes. The peptide was synthesized by solid-phase methods to provide amounts of several grams. The product was purified by chromatography on a 25 cm x 2 in. column of DuPont Zorbax Pro-10 C8 (10 micron) packing. Sample loads of 100-450 mg were chromatographed isocratically in 0.1% trifluoroacetic acid and 5% acetonitrile at a flow-rate of 110 ml/min. Under these conditions, the pure peptide fraction was eluted reproducibly between 15 and 22 min. After solvent removal and lyophilization, the recovery of pure peptide was 50% by weight.