Hydrolytic and Enzymatic Degradation of Photocurable Polymer Networks Comprising Ester-Urethane Building Block, PEGylated Fibrinogen and Catechol Units

Hydrophobic telechelic macromonomers derived from vegetable oil (VO) comprising ester-urethane linkages can be successfully photopolymerized after functionalization with methacrylic termini. While featuring hydrophobicity, they can be combined with PEGylated fibrinogen and methacrylated catecholamine to balance hydrophobic-hydrophilic properties. In this work, we performed hydrolytic and enzymatic degradation studies of amphiphilic (hybrid) UV-cured polymer networks in the presence of lipase . The degradation process was monitored by assessing structural changes via Fourier transform infrared spectroscopy, determining water uptake and weight loss, and revealing changes in surface morphology by micro-computed tomography. Incorporation of hydrophilic components into hydrophobic core contributed to accelerated degradation after 4 weeks due to better penetration of water molecules into the amphiphilic network as manifested by increased water uptake up to 50 wt.% and mass loss of 9 wt.%, respectively. We demonstrated that lipase is active towards ester bonds cleavage in amphiphilic hybrids. Importantly, polymer networks did not release acidic degradation products in an amount that could cause acidification of the medium. This study reveals that tailoring the molecular structure allows for customization of the susceptibility of cross-linked polymers to degradation, depending on the needs.