Biocompatible and degradable poly(2-hydroxyethyl methacrylate) based polymers for biomedical applications

The present work provides a new, well characterized hydroxyl functionalized biocompatible and degradable polymer that could be suitable for many different biomedical applications. Poly(2-hydroxyethyl methacrylate) (PHEMA) is a widely used and researched biocompatible polymer, but lacks degradability. In this work, degradable and less toxic PHEMA with ester linkages in the backbone could be successfully made by radical copolymerization with cyclic ketene acetal. The protection-deprotection chemistry at the hydroxyl group of HEMA was necessary for the formation of targeted polymers. The structure of the resulting polymers was unambiguously proved by 2D NMR techniques. The polymers were significantly less toxic with cell viabilities of more than 80% even for very high polymer concentrations (100 mg mL(-1)). The polymers were hydrolytically degradable under basic conditions and also showed surface and bulk degradation using macrophages. We also demonstrated promising positive results for the use of such polymers as sustained drug delivery systems.