Preparation Of Magnetic Porous Scaffolds And Study On Osteogenic Properties And Antitumor Properties

At present bone tumors is a thorny issue of clinical medicine.For the treatment of bone tumors,the only way is to remove it depengding on surgery.However the surgery of removing bone tumors can result in large bone defect,In addition to surgery,the radiation and chemotherapy before or after the surgery is not only killing tumor cells but also killing normal tissue cells.Therefore,it is urgent to find a new kind of multi-functional biological material which can not only repair the large area of bone defect while also inhibiting the growth of tumor cells.In the content of this paper,the following two parts are mainly studied.1.Using mechanical agitation and freeze drying technology can prepare the mesoporous bioglass/strontium ferrite/chitosan magnetic porous bioglass scaffolds?MBCS?perfectly.Also we resort to test means to analyse the phase and morphology of porous scaffolds.The properties of materials are explored through vivo and in vitro experiments in terms of?1?the osteogenesis for cell proliferation,signal pathways and the effect for large skull defect and repair;and?2?the anti-tumor,in which the MBCS material is used to the media.Let the scaffold explore the 808nm near-infrared to study the inhibition effect of on tumor cells and the volume change of tumor inhibition in vivo.2.Mixing and freeze drying method is used to prepare mesoporous silicate/strontium ferrite/chitosan magnetic mesoporous bioglass porous scaffolds?MCSC?.And the MCSC were characterized by XRD,VSM,FESEM and TEM and so on.Cell experiments in vitro and animal experiments are combined to explore MCSC material for osteoblasts promoting,the roles of skull defect repair and for the inhibition of tumor cells and inhibit the increase of tumor in vivo effect.Alkali catalyzed inorganic self-assembly method and etching reaction successfully let BGS convert to MBGS.MBGS present globular,and the diameter of each globular is between 200 nm.At the same time,the co-precipitation method can be used to prepare the laminated structure with a thickness of about 30nm,and the width between 50-150 nm of SrFe₁₂O₁₉.By combining mechanical agitation and freeze-drying,the pore diameter of MBCS was mainly distributed between70³00mm,and the porosity was more than 90%.MBCS has excellent magnetic properties and good ultraviolet visible absorption.By in vitro cell experiments and animal experiments show that MBCS doped with magnetic particles strength the ability of cell proliferation and differentiation.In MBCS,magnetic content in MBCS1:3 is most.The BMD,BV/TV and the new bone area of MBCS1:3 are 0.564±0.074 g/cm³,63±4%and 53±3%respectively,so The effect of skull repair is most significant in vivo of MBCS1:3.Moreover,under the condition of near infrared light,MBCS material as the medium of light conversion,2 min later MBCS is able to reach 43?,which is higher than that of tumor cells survive to achieve the purpose of anti-tumor.Because the magnetic content in MBCS1:3 is the most,near infrared absorbing ability stronger,tumor inhibition effect of MBCS1:3 is most obvious.