Robust and Degradable Hydrogels from Poly(ethylene glycol) and Semi-Interpenetrating Collagen

Poly(ethylene glycol) (PEG) and interpenetrating collagen can be used to synthesize hydrogels that are elastomeric-like, can withstand reversible loadings, degrade, and are bioactive. Here we present the synthesis of a hydrogel system made of PEG modified with lactide and acrylate end groups and then photo cross-linked in the presence of type I collagen. The hydrogel precursor solutions are low viscous and the cross-linked hydrogels form elastomeric-like polymer networks. Mechanical properties of the hydrogels were found to depend predominantly on PEG concentration and less on collagen. This is possibly due to a balance of molecular interactions that reinforce and weaken the network structure. Hydrogel degradation times were strongly dependent on temperature. The experimental results from this project show how to generate robust, and degradable hydrogels containing bioactive collagen. The data show promise and show the versatility of making biotechnologically relevant soft materials from a few components.