Metamorphosis of HPLC
We present the further development and fine-tuning of an efficient, economic (<3 molar excess) and environmentally friendly (6 ml organic waste/cycle) procedure for peptide synthesis, using fast amino acid coupling cycles (1.7 min/cycle). The designed setup can assist the synthesis of highly pure (>80%) raw materials even for long (up to 30 aa.) and/or difficult sequences. The significant reduction of the coupling time by using the effective PyAOP and DIC/HOBt coupling reagents was achieved and virtually racemization free (L-His/D-His <1-5 %) peptides can now be synthesized, even at high column temperate: T = 70 °C. The purity of the product and the efficacy of the synthesis were evaluated using different solid phase supports and protocols. We successfully completed the synthesis of “difficult sequences” (e.g. Insulin B-chain, Cecropin A(1-7)-Melittin (2-9) hybrid peptide) wasting only a fraction of the organic solvents compared to other methods, furthering peptide chemistry toward a greener approach.