Electrochemical Study Of Legal System For Mixing Magnesium Hydroxyapatite

The composition of Hydroxyapatite [Ca₁₀（PO₄）₆（OH）₂, referred to as HAP or HA]is close to the inorganic components of bone tissue in the organism, and it has a verygood biocompatibility. Titanium and titanium alloys have been the most widely used asimplant materials in clinical. Therefore, the HAP coating based on titanium material hasthe high strength of metallic materials and high toughness. Meanwhile it has goodbiological activity. The inorganic components of natural bone is HAP crystallization,and it also contains a variety of other trace elements. For example, magnesium has agreat influence on the nature of bone matrix outside the cells, which determines thebrittleness of the bone matrix. The reduction of magnesium affects the metabolism ofbone, such as the end of skeletal growth, reducing the activity of osteoblasts and soon.Therefore, how much amount of Mg should be mixed in the artificial bone materialsso as to improve the biological activity of the implant cause the extensive attention fromresearchers.In this paper, HAP-Mg coating based on pure titanium was prepared by theelectrochemical deposition method to improve the biocompatibility. In addition，itscombination strength also increased. It indicated that the uniform and exquisiteHAP-Mg coating could be formed on Ti substrates by electric deposition method withcontrolling the different experimental parameters, and HAP-Mg coating was morecompact than HAP coating. Meanwhile, there was a certain degree of porosity, whichwas beneficial for the adhesion of bone cells. XRD, EDS, and FTIR analysis showedthat the magnesium ion did not change the composition of the coating after sintering,but it affected the growth of HAP.The biological activity of samples was tested in physiological fluid environment,mainly on the ability of biological remineralization. The biological remineralization ofHAP coating and HAP-Mg composite coating was found in SBF experiments. Thecomparison shows that adding magnesium ions to form dense coatings in theelectrodeposition could slow down the dissolution of hydroxyapatite in body fluids, andit helped to prolong the life of the implant. Through the immersion test in CPBSsolution, It can be found that the HAP-Mg coating had a certain solubility. Because HAP-Mg coating is dense, it had a better corrosion resistance than HAP.