Convergent solid-phase peptide synthesis. 12. Chromatographic techniques for the purification of protected peptide segments.

The purification of a range of protected peptide segments has been carried out using modified reversed-phase chromatographic techniques in which DMF was added to the water and acetonitrile mixtures used as eluents. The purity of the recovered peptides was excellent and recoveries were high in all cases, even for longer hydrophobic segments. In several cases purifications were carried out on the hundreds of milligrams scale. For protected peptide segments containing Met, protection as the sulfoxide avoids its unwanted alkylation and oxidation, and the increased overall polarity can be useful in the purification of protected peptides incorporating this residue.