Biological safety of silk fibroin/nano-hydroxyapatite composites / 中国组织工程研究

ABSTRACT

BACKGROUND:Silk fibroin has excel ent biocompatibility, biodegradability and unique mechanical properties. Its composite, silk fibroin/nano-hydroxyapatite, can simulate the composition and structure of nature bone tissue, contributing to remedying the insufficient mechanical properties of nano-hydroxyapatites. OBJECTIVE:To observe the biological safety of silk fibroin/nano-hydroxyapatite composites. METHODS:Silk fibroin/nano-hydroxyapetite composite biomaterial was synthesized by the coprecipitation method using silk fibroin, calcium chloride and diammonium phosphate as raw materials. According to the demands of International Standard Organization (ISO10993) and Technical Evaluation Standards of Biomedical Materials and Medical Instruments promulgated by Chinese Board of Health (GB/T 16886), experiments of cel toxicity in vitro, acute toxicity and hemolysis were investigated to evaluate the biocompatibility of silk fibroin/nano-hydroxyapetite composite. RESULTS AND CONCLUSION:L929 cel s co-cultured with silk fibroin/nano-hydroxyapatite composite leaching liquor had good cel morphology, metabolism and proliferation. The leaching extract of silk fibroin/nano-hydroxyapatite composite injected into mice intraperitoneal y had no significant adverse reactions. And silk fibroin/nano-hydroxyapatite composite extracts caused 2.39%blood hemolysis, less than the international standards 5%. These experimental results on cel toxicity test in vitro, acute toxicity and hemolysis met the demands of ISO10993 and GB/T, which show the biological safety of the silk fibroin/nano-hydroxyapatite composite for clinical application.