P131-M Performance Evaluation of a New 6-Channel, Small-Scale Peptide Synthesizer.

Protein Technologies has developed a new parallel peptide synthesizer able to perform efficient synthesis at scales from 10 to 350 μmoles. A bench-top model, the Prelude incorporates several desirable features, including extra solvent and amino acid bottle positions, ‘single-shot option’ for specialty amino acids, and an effective mechanism for improved solvent washes. Our objective was to field test the performance at the lower scale range of this instrument, evaluate the quality peptides with diverse sequences, including modified amino acids and derivitization, and to compare the results with those obtained from parallel syntheses on other instruments. We synthesized approx. 80 peptides. The sequences were anionic, cationic and hydrophobic, linear and branched. Some contained phosphorylated amino acids, and some of the peptides were derivitized with biotin or fluorescein. Three quarters of the peptides had a crude purity greater than 50%, many of those exhibited purities that were better than 80%. Seven extra amino acid reservoirs permitted unattended synthesis (no manual additions) of peptides containing phosphoserine and phosphotyrosine as well as several pseudoprolines. Derivitizations also proceeded automatically, as did hydrazinolysis of [(4,4-dimethyl-2,6-dioxycyclohex-1-ylidene)ethyl] (Dde) protective groups. High performance liquid chromatography and matrix-assisted laser desorption ionization mass spectrometry will illustrate the conclusions.