Isocyanate-terminated urethane prepolymer as bioadhesive material: evaluation of bioadhesion and biocompatibility, in vitro and in vivo assays

Attempts have been made to evaluate the degree of bioadhesion and biocompatibility of a synthesized urethane prepolymer with specially tailored microstructure. Wetting behaviour and extent of interfacial adhesion of the prepared prepolymer towards biological substrates were examined by in vitro methods. The former was carried out by measuring the contact angle between drops of the prepolymer liquid and a biological surface, while the latter was determined from the force between the prepolymer and tissue model or mucus. The obtained results exhibited good tissue wettability and bioadhesion by the prepolymer. Preliminary evaluation of biocompatibility for the uncatalytically cured prepolymer films was performed by cytotoxicity and histotoxicity experiments. Results showed a significant growth for the adhered L929 fibroblast cells within a period of 5 days incubation. Also, no severe inflammatory tissue response towards the samples implanted in rabbit for 16 weeks was seen. These observations can support the potentiality of the designed urethane prepolymer to be applied as hemostatic agent.