Catalytic peptide/hemin complex from ester-amide exchange reaction mediated by deep eutectic solvents.

The functions of peptides often emerge upon their self-assembly or binding with other co-factors. However, the synthetic complexity makes these functional peptides intractable. Here, we utilize the ester-amide exchange reaction in deep eutectic solvents to generate peptide libraries from unactivated amino acids. This strategy leads to peptide mixtures that exhibit hemin-binding capability and peroxidase-like activity.