Study On Antibacterial Modified Hydroxyapatite Whisker Porous Bone Tissue Engineering Scaffolds

With the development of medical materials,as a bone repair scaffold material,bioceramic materials have become more and more widely used.As a class of biomedical ceramic materials,hydroxyapatite whiskers have attracted much attention because of their good biocompatibility and osteoinductivity.However,the traditional hydroxyapatite whiskers have been affected to a certain extent as bone scaffold materials due to their lack of antibacterial properties.For example,in orthopedic surgery,patients often have difficulty in recovering after surgery due to bacterial infection problems or even failure.Studies have shown that some metal ions and nanoparticles,such as silver ions and nano-zinc oxide particles,have a strong broadspectrum antibacterial ability,making research on antibacterial modified hydroxyapatite whiskers and bone tissue engineering scaffolds meaningful The main research of this article is as follows:(1)Silver-doped hydroxyapatite whiskers(Ag-HAw)were successfully prepared by template-directed homogeneous precipitation method.With the incorporation of silver ions,the whisker morphology developed from needle to lath and appeared flowers The shape of hydroxyapatite whiskers and spherical materials also shortens,and the main distribution is between 60?m-160?m,the longest can reach more than169?m,and the aspect ratio is distributed between 5-40;according to XRD and TEM results With the incorporation of silver ions,the OCP phase appears in the product,the interplanar spacing increases,and the crystallinity decreases to a minimum of 72.95%;according to ICP-OES data,the incorporation ratio of silver ions increases with the incorporation amount Large and low,the mixing ratio is between 45%-73%;according to the cytotoxicity test,silver-doped hydroxyapatite whiskers have no cytotoxicity;according to antibacterial experiment results,silver-doped hydroxyapatite whiskers It has an inhibitory effect on Escherichia coli and Staphylococcus aureus,among which the inhibitory effect on E.coli is higher than that of Staphylococcus aureus.(2)Nano-zinc oxide composite silver-doped hydroxyapatite whiskers(ZnO / AgHAw)were prepared by the sol-gel method.Nano-zinc oxide particles with a diameter of 15-45 nm appeared on the surface of the whiskers.As the zinc oxide content increases,the particle diameter increases and agglomeration occurs.According to XRD results,the peak of zinc oxide appears in the spectrum,the product contains zinc oxide,the nanoparticles on the whisker surface are nano zinc oxide,and the OCP phase that appears during the preparation of silver-doped hydroxyapatite whiskers disappears and appears New calcium-zinc phosphate phase;surface scan and energy spectrum results show that ZnO / Ag-HAw contains silver,zinc and other elements,and its element distribution points are less than calcium and phosphorus;cytotoxicity results show that ZnO/Ag-HAw has no Cytotoxic,and the addition of nano-zinc oxide improves the cell proliferation rate,therefore,nano-zinc oxide improves the biocompatibility of whiskers;antibacterial results show that ZnO / Ag-HAw is antibacterial to E.coli and Staphylococcus aureus The effect,and the antibacterial ability of the whisker composite material against Staphylococcus aureus is improved.(3)The ZnO/Ag-HAw porous scaffold material was prepared by the pore-forming agent method.The actual porosity of the porous scaffold was 18.0%,34.3%,and 53.0%,and the corresponding compressive strength was 5.40 MPa,3.27 MPa,1.10 MPa.Through comprehensive comparison of the data,the scaffold with a porosity of 34.3%and a compressive strength of 3.27 MPa is more in line with the requirements of human bone scaffolds,and its pore size is between 30 ?m and 180 ?m.In vitro cytotoxicity experiments show that the cytotoxicity level of the scaffold material 0,showing no cytotoxicity.It can be seen from the results of cell adhesion experiments and scanning electron microscopy that the cells on the surface of the scaffold are irregularly flat and spherical,the cells grow pseudopodia,the shape is good,and the scaffold shows good cell compatibility and biological activity.