Study On Regulating Osteogenic Behavior Of Nano Calcium Phosphate Mineral Collagen Composite Biomaterials

With the intensification of population aging,orthopedic diseases have attracted widespread attention,and bone repair materials have become one of the focuses and hotspots of research.However,the applicability and repair efficiency of materials need to be improved.Collagen and calcium phosphate are the main components of natural bone tissue and are also important materials for the preparation of bone tissue engineering scaffolds.However,the low mechanical strength of collagen and the difficulty of controlling the surface morphology of calcium phosphate materials limit its large-scale application.This paper focuses on collagen and calcium phosphate,and a variety of technologies in interface material engineering are used to prepare a series of bone repair and osteoinductive materials with porous properties,piezoelectric activity,and antibacterial activity,including those with porous interface structure.Osteoinductive coating,piezoelectric active osteoinductive scaffold,and antibacterial bone repair film with porous mineralized coating,and carried out research on osteogenic behaviors.(1)Through layer-by-layer self-assembly and in-situ biomineralization technology,a collagen calcium phosphate mineralized film is prepared on a titanium alloy substrate,and the thickness of the film is controlled by layer-by-layer self-assembly to precisely control the porous calcium phosphate surface.The composition and porous surface of the calcium mineralized coating effectively promote the osteogenic differentiation of cells,and can promote ectopic bone formation in animals.(2)The interface mineralization coating is combined with the piezoelectric dielectric film to prepare an osteoinductive interface that uses the piezoelectric effect to promote the release of active factors.Use PEI to reduce GO to obtain rGO-PEI,and then prepare rGO-PEI/PVDF-HFP composite piezoelectric film by casting method,and modify the piezoelectric film with collagen calcium phosphate mineralized coating for drug loading and release.The composite piezoelectric film has excellent piezoelectric properties.The collagen calcium phosphate mineralized coating can promote the release of drugs and maintain protein activity under piezoelectric response.The released BMP-2 protein effectively promotes the osteogenic differentiation of cells.(3)The piezoelectric coating and the microporous mineralized structure are integrated and prepared on a porous polyurethane scaffold to obtain an osteoinductive scaffold with piezoelectric activity;piezoelectric signals are generated by body movement to promote intracellular Ca2+influx,thereby promoting osteogenic differentiation of cells,and promote ectopic bone formation in animals.(4)The self-assembly technology of shear flow driving force is used to assemble collagen calcium phosphate mineralized film and chitosan/poly acrylic acid film on both sides of the biodegradable biofilm substrate.At the same time,the antibacterial function of the film and the function of repairing bone defects are realized.