Preparation And Characterization Of Magnetic Nano Bio-Composite

The basic reseach of magnetic biomaterial have already proved that magnetism can significantly accelerate the growth of cell. Magnetite (Fe₃O₄) is widely used in biomedicine area because of its well superpara magnetism and good biocompatibility. In this paper, we respectively compounded magnetite into chitin film, PLA (poly -lactic acid) nano fiber, and porous HA scaffold to prepare magnetic nano bio-composit.Firstly, surfactant-mediated approach was used to prepare highly stabilized magnetic particles. Soudium oleated (SD) and poly-ethylene glycol (PEG) were used as the surfactants in the co-precipitation procedure. The results indicate that, magnetite prepared by surfactant-mediated approach is qualified with good superpara magnetism and better compatibility, which can be used for clinics.Secondly, sol-gel method was introduced to prepare magnetic chitin compound film. The results indicate that the uniform magnetic film is qualified with well superpara magnetism and better mechanical property than pure chitin film.Thirdly, electro-spinning was introdueced to prepare magnetic nano fiber. The results indicate that magnetic nano fiber is qualified with well superpara magnetism and better mechanical property than pure PLA fiber. The magnetic nano particles which introduced to PLA fiber can strengthen the fiber; and meanwhile, it speeds up the degradation process of the fiber when soaking in PBS.Fourthly, by dipping HA scaffold in magnetic PLA slurry, magnetic porous scaffold was prepared. The results indicate that the slurry can produce a uniform magnetic PLA film on the surface of HA scaffold, and it has good superpara magnetism and better mechanical property because of well dispersed nano magnetic particles. During soaking in 2×SBF, small cave appeared on the surface provides the channel for HA to grow inside the coating. Under magnetic field, a few HA-like mineral deposite on the surface of the coating of magnetic scaffold. Duiring soaking, the magnetic scaffold degradats faster, and the magnetic field speeds up the process.Lastly, the biocompatibility of all the materials was studied using cell culture analysis. The results indicate that all the magnetic compounds show better biomcompatilbility than their pure matrix material, but the biocompatibility would decrease when the magnetite content is over too much.