Introducing lactide-based biodegradable tissue adhesives

Lactide-based low molecular weight copolymers were synthesized and investigated as tissue adhesives. The oligomers were composed of di or trifunctional central connecting segments and lateral PLA blocks. Copolymers with glass transition temperatures in the 20-25 °C range, were found to perform better. Strong connection was found between the length of the PLA blocks, the glass transition temperature (T_g) and the Adhesive Failure Strength of the different materials. Flexible ε-caprolactone (CL) molecules were inserted into the PLA blocks, to produce longer biodegradable chains and improve the adhesive strength of the oligomers, while keeping their T_g within the appropriate temperature interval. Branched oligomers consisting of a trimethylolpropane central molecule and three LA-CL segments, displayed enhanced in vitro adhesive properties.