Multifunctional thermoresponsive designer peptide hydrogels.

Abstract

We report the synthesis and characterization of multifunctional peptides comprised of a hydrogel forming β-sheet peptide segment and a matrix metalloproteinase 2 substrate containing a propargylglycinyl linker that is further derivatized with an RGD peptide sequence via "click" chemistry. In contrast to currently known systems, these multifunctional peptides formed gels that are stiffer than those formed by their respective precursors. All the peptides showed reversible thermoresponsive properties, which render them as suitable lead systems for a variety of possible biomedical applications. In general, it has been frequently observed that chemical biofunctionalization of peptide hydrogels adversely affects peptide assembly, hydrogel formation or mechanical properties, which severely compromises their application. A functionalization protocol that allows to generate peptide hydrogels that display significantly improved mechanical properties over their unfunctionalized counterparts is reported in this work. These peptides also showed thermoresponsive viscoelastic characteristics, including an example of a peptide hydrogel that displays lower critical solution temperature behaviour.