Supramolecular Peptide Gels: Influencing Properties by Metal Ion Coordination and Their Wide-Ranging Applications

Supramolecular gels have been an area of interest in many research fields. They provide a means to understand assembly of nanostructures, and through the use of amino acid- and peptide-based gelators they can give insights into the similar assembly pathways of their more complex structural counterparts. Bio-inspired metal coordination, such as histidine-copper coordination, in the supramolecular assembly of these gelators is one method for furthering our understanding and development of these materials. Metal-gelator coordination mimics biologically relevant metal-peptide coordination, thus influencing hydrogel self-assembly and mechanical properties, including biodegradability, biocompatibility, tunability, and recyclablity, while the metal coordination can functionalize the gels to allow for widespread applications in biomedical industries (e.g., drug delivery), waste management, and catalysis. This review aims to discuss recent insights into the supramolecular assembly of gels involving metal ions, as well as a few key areas of application using metal interactions and incorporation.