Development of a biodegradable bioadhesive containing urethane groups

Surgical adhesives consist on an attractive alternative to suturing or stapling since they can accomplish other tasks, such as haemostasis and the ability to seal air leakages. The application of adhesives would also reduce the surgeries procedure time since they represent an easier and faster method to establish tissue adhesion. The aim of this work was the development of a biodegradable urethane pre-polymer that presents the capacity of reacting with the amino groups present in the biological molecules. Urethanes based on polycaprolactone diol (PCL) were synthesized by reaction of the molecule either with isophorone diisocyanate (IPD-isocyanate) or hexamethylene diisocyanate (HDI-isocyanate). The characterization of the materials was accomplished by: ATR-FTIR (Attenuated Total Reflectance-Fourier Transform Infrared), determination of swelling capacity, stability of NCO groups in the presence of humidity conditions, reaction with aminated substrates (as a simulation of the living tissues) and determination of surface energy by contact angle measurement. The haemocompatibility of the PU was also evaluated by thrombosis and haemolysis tests.