HA/CuO/SrCO_(3)梯度复合涂层的制备及体外生物活性

Preparation and in vitro Bioactivity of HA/CuO/SrCO_(3) Gradiently Composite Coating

在羟基磷灰石(HA)悬浮液中,以正丁醇为分散介质,三乙醇胺为乳化剂,成骨微量元素化合物CuO和SrCO_(3)作为添加剂,Ti片为基材,壳聚糖(CS)为造孔剂,依次通过区带电泳分布并在反向电场作用下电泳沉积,得到HA/CS/CuO/SrCO_(3)复合涂层,经700℃高温煅烧2 h后,制得HA/CuO/SrCO_(3)复合涂层.通过X射线衍射(XRD)、傅里叶变换红外光谱(FTIR)、场发射扫描电子显微镜(FESEM)、能量色散光谱仪(EDS)、劳埃德万能材料试验机、电化学工作站、模拟体液培养和抑菌实验等手段对复合涂层进行测试与表征.结果表明,Ca,Cu和Sr元素含量在HA/CuO/SrCO_(3)复合涂层的径向上均呈现梯度分布;复合涂层与钛基材的结合强度达33.0MPa;循环伏安(CV)曲线和Tafel极化曲线测试表明,复合涂层在N-2-羟乙基哌嗪-N′-2-乙磺酸(HEPES)模拟体液(H-SBF)中电化学性能稳定,耐腐蚀性较强;在H-SBF中培养24 d后,复合涂层表面完全碳磷灰石化;抑菌实验发现,复合涂层粉末对大肠杆菌和金黄色葡萄球菌的抑菌率分别为81.82%和71.86%.

In hydroxyapatite(HA)suspension,n-butanol as dispersion medium,triethanolamine as emulsifier,two osteogenic trace element compounds CuO and SrCO_(3) as additives,Ti sheet as substrate,chitosan(CS)as porogen,an HA/CS/CuO/SrCO_(3) composite coating was obtained by zonal electrophoresis distribution and electrophoretic deposition under the action of reverse electric field.And then,an HA/CuO/SrCO_(3) composite coating was prepared after high temperature calcination at 700℃for 2 h.Some equipments and methods such as powder X-ray diffraction(XRD),Fourier transform infrared spectroscopy(FTIR),field emission scanning electron microscopy(FESEM),energy dispersive spectroscopy(EDS),Lloyd universal material testing machine,electrochemical workstation,culture in simulated body fluid and inhibition experiment,were used to test and characterize the composite coatings.The results show that all of the contents of Ca,Cu and Sr elements had presented a gradient distribution in the radial direction of the HA/CuO/SrCO_(3) composite coating.The bonding strength between the composite coating and the Ti substrate was 33.0 MPa.The composite coating possessed stable electrochemical performance and strong corrosion resistance in(N-(2-hydroxyethyl)piperazine)-N'-2-ethane sulfonic acid(HEPES)simulated body fluids(H-SBF)under tested by cyclic voltammetry(CV)curves and Tafel polarization curves.The surface of the composite coating was apatite-carbonated completely after cultured in H-SBF for 24 d.The inhibition rates of the composite coating powder against Escherichia coli and Staphylococcus aureus were 81.82%and 71.86%,respectively.