Chirality Effect on Physical and Biological Properties of Peptide-Based Hydrogels

The self-assembly of peptide-based building blocks into ordered structures is widely exploited for the development of novel biomaterials, including hydrogels. In this review, we analyze the effect of chirality on the ability of peptides to form hydrogels. We describe systems composed of peptides of opposite chirality i.e. peptides composed of all L- or D-amino acids and peptides composed of amino acids with alternate chirality, i.e. one L- and D-amino acid or one block containing all L-amino acid followed by one block composed of all D-amino acids. Finally, we illustrate systems composed of mixtures of L- and D-peptides. The structural features of these compounds are discussed. We further compare the mechanical properties of hydrogels formed by homochiral and heterochiral peptides. Finally, we discuss the potential biological applications of these systems, focusing on the differences between hydrogels formed from peptides of opposite chirality or mixed chirality.