Joseph Michalewsky

Preparative high-performance liquid chromatography applied to peptide synthesis☆

A variety of protected synthetic peptides were purified by high-performance liquid chromatography on pre-packed silica gel columns. The compounds varied in protecting groups, amino acid composition and molecular weight. Flow-rates of two to four column volumes per hour were employed, with resultant back pressure of less than 150 p.s.i. A typical column load of 0.2-5 g was purified in 2-5 h.

Analysis of DNA derivatives. II. High-pressure liquid anion-exchange chromatography of deoxyribonucleotides.

Abstract A procedure for assaying deoxyribomononucleotides released by diesterase digestion of oligomers is reported. The method is based on high-pressure anion-exchange chromatography on Zipax SAX at ambient temperature using a single buffer of low ultraviolet absorption. A simple procedure for determining peak overlap is included.

Isolation of Thymosin α1 from Thymosin Fraction 5 by High Performance Liquid Chromatography

Abstract An HPLC system for quickly isolating individual peptides from thymus extract is described. A series of reversed phase separations followed by ion-exchange HPLC produces pure peptides with minimal chromatographic time. A 2.4 gram column load of crude extract was carried through to the isolation of 4 mg of pure thymosin α1 within 6–8 hours of chromatography.