Biological evaluation of poly-l-lactic acid composite containing bioactive glass

Abstract

Biodegradable and biocompatible materials are the basis for medical application. As an initial step for developing bone internal fixation materials, the biological evaluation of poly-l-lactic acid/bioactive glass (PLLA/BG) composite in vitro and in vivo, including the hemolysis test, pyrogen test, acute systemic toxicity test, genetic toxicity test, anaphylaxis test, MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) test, direct cell culture and in vivo implant experiment, was performed. The results indicated that PLLA/BG composite showed no acute systemic toxicity, genetic toxicity, anaphylaxis reaction, and pyrogen reaction, and the hemolysis ratio was 0.39%. MTT assay indicated that no cytotoxic effect was observed for the PLLA/BG composite, and in addition, a significant increase in cellular activity compared to the negative control group was found. Excellent adhesion between fibroblast and PLLA/BG material was observed, the fibroblasts cultured on the PLLA/BG composite substrates revealed a higher proliferation and differentiation rate than those on the pure PLLA substrates. In vivo implant experiment showed that the PLLA/BG composite could maintain the mechanical properties during the course of fracture therapy, and the malleolar fracture of rabbits was healed in 8 weeks on the whole. Therefore, PLLA/BG composites have a promising biological response as a potential implant material.