Construction, Structure And Biological Properties Of Magnetic Mesoporous Bioglass Bone Scaffold

In this paper, the multifunctional magnetic mesoporous bioactive glass (MMBG) powder have been synthesized through a sol-gel method, and the magnetic mesoporous glass/chitosan composite with a3D scaffold have been built by using the template method. All these are prepared through introducing the magnetic Fe3O4nanoparticles as magnetic source. The phase structures, morphology, mesoporous structure and magnetic properties of as-prepared products were thoroughly characterized using X-ray diffraction (XRD), transmission electron microscope (TEM), automatic surface area and porosity analyzer (BET) and a vibrating sample magnetometer (VSM), respectively. In particular, the biocompatibility and drug delivery property, bactericidal property of the MMBG/CS scaffold have been detailed analyzed. The results are summarized as follows:1. By introducing the magnetic source (Fe3O4) into the traditional biological glass, the MMBG powder with highly ordered mesoporous structure was prepared with the non-ionic surfactant P123as the soft templates. Owing to the large surface area of385.50m2/g, pore diameter of4.98nm, high pore volume of0.60cm3/g, and its superparamagnetism with a saturation magnetizations (Ms) of1.44emu/g, the MMBG powder can be loaded with antibiotic drugs (gentamycin sulfate) to exhibit the drug delivery performance. The study found that it can continue to release more than144h effectively, which is very closed with the postoperative prophylactic antibiotics in the treatment cycle, while the slow release process of the traditional biological glass (NBG) was’t observed. Therefore, MMBG can offer ideal antibiotics and other drugs slow-release system for postoperative anti-infection treatment of bone repair.2. Then, the magnetic mesoporous bioglass/chitosan composite scaffold (MMBG/CS) was built through simulating the microstructure of natural bone. The3D scaffold are consisted of mesoporous (d=4.98nm) and macroporous (d=100-300μm), which providing the suitable space for the cell process of proliferation and metabolism. While the magnetic particles have made an impact on the growth orientation of hydroxyapatite crystal, the MMBG/CS transformed into flowers apatite at surface, explaining that the existence of the magnetic particles can not only help the in vivo biological mineralization, but also encourage the bone repair process.3. The cytocompatibility and bactericidal property of the MMBG/CS scaffold have been detailed analyzed with the nonmagnetic sample as control. The results show that the MMBG/CS has better biocompatibility and biological activity in vitro by promoting cell adhesion in the early stages, cell spreading and cell proliferation. MMBG/CS loaded with durgs showed more stabilize and more effective bacteriostasis, which may be contributed to the micro magnetic field generated by magnetic nanoparticles (Fe3O4). With good biocompatibility, biological activity and ideal anti-infection effect, MMBG/CS, therefore, can be used as a clinical compound system of bone fill and antibiotics controlled-release.