Porous photo-crosslinked hybrid networks based on poly(trimethylene carbonate-co-ε-caprolactone) and recombinant human-like collagen

Hybrid hydrogel networks were prepared from recombinant human-like collagen (rh-collagen) and poly(trimethylene carbonate-co-ε-caprolactone) (P (TMC-co-ε-CL)) to overcome the mechanical and bioactivity limitations associated with the respective individual networks. Both polymers were functionalised with methacrylic anhydride to yield photo-crosslinkable materials. Porous hybrid networks of different compositions were prepared by photo-crosslinking frozen mixtures of solutions of the functionalized polymers in acidified DMSO. After extraction with water, the obtained networks had the intended compositions, high porosities and gel content. Upon equilibration in water, the total water content was found to increase with increasing collagen content. The tensile properties and suture retention strength (SRS) of the hybrids were improved compared to a rh-collagen network. In particular, the 17:83 wt% rh-collagen:P(TMC-co-ε-CL) network had considerably higher toughness and SRS, showing promise as a hybrid hydrogel network to be further investigated for tissue engineering purposes.