Biocompatibility and biodegradability of implantable drug delivery matrices based on novel poly(decane-co-tricarballylate) photocured elastomers

Abstract

Visible light photo-cross-linked biodegradable amorphous elastomers based on poly(decane-co-tricarballylate) (PDET) with different cross-linking densities were synthesized, and their cytotoxicity, biocompatibility, and biodegradability were reported. Cytotoxicity of PDET extracts of the elastomers was assessed for mitochondrial succinate dehydrogenase activity by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT assay) and inhibition of [3H] thymidine incorporation into DNA of epithelial cells. The in vivo biocompatibility and biodegradability were determined by subcutaneous implantation of PDET microcylinders in 25 male Sprague-Dawley rats over a period of 12 weeks. The in vivo changes in physical and mechanical parameters of the implants were compared with those observed in vitro. The treated epithelial cells revealed no signs of cytotoxicity, and the elastomer degradation products caused only a slight stimulation to both mitochondrial activity and DNA replication. The implants did not exhibit any macroscopic signs of inflammation or adverse tissue reactions at implant retrieval sites. The retrieved implanted microcylinders maintained their original geometry and extensibility in a manner similar to those observed in vitro. These new elastomers have excellent biocompatibility and are considered promising biomaterials for controlled drug delivery and tissue engineering applications. © SAGE Publications 2011.