Biocompatibility of magnetic chitosan microspheres / 中国组织工程研究

ABSTRACT

BACKGROUND:Chitosan modification for magnetic iron oxide nanoparticles can improve the agglomeration and stability of magnetic iron oxide nanoparticles, and in addition, it can be used for tumor hyperthermia and gene therapy in the future. OBJECTIVE:To explore the biocompatibility of magnetic chitosan microspheres which have the potential application in tumor hyperthermia and gene therapy. METHODS:Magnetic iron oxide nanoparticles were prepared using the modified chemical precipitation. Phacoemulsification method was used to add chitosan into magnetic iron oxide nanoparticles in the preparation of magnetic chitosan microspheres. Then, the fol owing tests were performed. (1) Cytotoxicity testL-929 cells were cultured in 1640 medium, polyacrylamide monomer solution, 100%, 75%, 50%, 25%of magnetic chitosan microsphere extracts. (2) Hemolysis testMagnetic chitosan microspheres leaching solution, saline and distil ed water were added. (3) Micronucleus testKunming mice were intraperitoneal y injected with magnetic chitosan microspheres suspension containing 5, 3.75, 2.5, 1.25 g/kg iron oxide magnetic fluid, cyclophosphamide and saline, respectively. RESULTS AND CONCLUSION:Magnetic chitosan microspheres of 200-300 nm in diameter had an increased dispersion effect. The result of 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay showed that the toxicity of the material on L-929 celllines belonged to no cytotoxicity. In the hemolysis test, the hemolysis rate of magnetic chitosan microspheres was 0.69%far less than 5%. In the micronucleus test, magnetic chitosan microspheres suspension did not cause DNA fragmentation and aneuploidy, and did not result in genetic toxicological effects produced by micronuclei. The magnetic chitosan microspheres did not appear with cacogenesis and mutagenesis. From the results, magnetic chitosan microspheres are a kind of high biocompatibility material.