Viscoelastic Behavior of Environmentally Sensitive Biomimetic Polymer Matrices

Abstract

By incorporating polysaccharide−peptide interactions into poly(ethylene glycol) hydrogels, we created a unique polymer matrix exhibiting characteristics imparted by both covalent and physical cross-links. Dynamic mechanical testing revealed that the properties of this system were sensitive to temperature changes and thermally reversible. At lower temperatures and higher frequencies, the elastic response was dominated by physical cross-links created by associations between heparin and heparin binding peptides; the matrices were stabilized by covalent cross-links at higher temperatures. Furthermore, the strength of the physical cross-links depended on the relative affinity between heparin and heparin binding peptides. This system could serve as a model to investigate how the presence of both physical and covalent cross-links influences the viscoelastic behavior of biomimetic polymeric materials.