Osteogenic Activity And Antibacterial Property Of Porous Zinc-incorporated Coating Prepared By Plasma Electrolytic Oxidation

Part I Preparation of porous zinc-incorporated coating by plasma electrolytic oxidationObjective: To prepare porous zinc-incorporated coating by plasma electrolytic oxidation technique,and to detect the characterization of the novel coacting.Method: Electrolyte zinc acetate was Introduced in the plasma electrolysis oxidation,and to prepare porous and copper-incorporated Ti O2 coating injected Zn by plasma electrolytic oxidation,then the chemical composition of the microporous nano coating,appearance characteristics,mechanical strength and ionic dissolution material were characterized.Result: Through the introduction of zinc ions in the PEO electrolyte solution,it can successfully inject Zn in nanoscale porous titanium surface containing zinc coating;after the injection of zinc ion of PEO coating surface morphology,phase composition,mechanical strength,elastic modulus,hydrophilic did not have a significant impacted.After the injection of zinc ions,the calcium and the phosphorus ion were reduced.When Zinc-PEO soaking was in buffer solution,it can release plasma zinc,phosphorus and calcium in the buffer solution.Conclusion: It can successfully inject zinc ions in microporous nano coating on the surface of Ti O2 by plasma electrolytic oxidation process of nano coating on titanium surface microporous at the same time.After the injection of zinc ions,it did not have been significantly changed the microporous nano coating surface morphology,phase composition,mechanical strength,elastic modulus and hydrophilicity.It Showed that the porous zinc-incorporated coating prepared by plasma electrolytic oxidation may be a better surface material for its low dissolution rate.Part II The influence of porous zinc-incorporated coating prepared by plasma electrolytic oxidation on osteoblastic bioactivityObjective: To explore the influence of porous zinc-incorporated coating prepared by plasma electrolytic oxidation on osteoblastic bioactivity.Method: The Zn-Ti O2 sample was as the experimental group,with the Ti O2 group as the control one,inoculated development respectively,according to a certain density of MG63 cells.CCK 8 method was having been detected the adhesion and proliferation of MG63 cells on the surface of the coating;Scanning electron microscopy(SEM)scanning was having been detected the spreading of MG63 cells on the surface of the coating;Inverted fluorescence microscope was having been detected the expression of cytoskeletal protein(Actin)to MG63 cells;It had been detected alkaline phosphatase(ALP)activity by P-nitrophenyl phosphate R substrate method;Related gene expression was having been detected by RT-PCR method.Result: CCK8 method showed that Zn-Ti O2 group in 6,9 and 12 hours after the surface adhesion of MG63 cells significantly more than Ti O2 group,the difference was statistically significant(p < 0.05);Zn-Ti O2 group was in 3,5and 7 days proliferation of MG63 cells significantly more than the Ti O2 surface groups,the difference was statistically significant(p < 0.05).After 12 hours,the electron microscope scanning showed that the Zn-Ti O2 group of osteoblast which spreaded out was better than that of the Ti O2 group.The study of Inverted fluorescence microscope showd that the Zn-Ti O2 group was better than that of the Ti O2 group.The Zn-Ti O2 group were significantly higher than that of the Ti O2 group,The difference was statistically significant(p < 0.05);In the seven day,The Zn-Ti O2 group was still higher than that of the Ti O2 group with the activity of alkaline phosphatase,but it was no statistical significance(p > 0.05).Two groups of the ALP,Col 1and OC gene expression were increased with the extension of incubation time;the Ti O2 group was obviously higher than that of the Ti O2 group,Which the ALP gene was in three and five days,the Col 1 gene was in three,five and seven days,the OC gene was in seven days;it has statistical significance(P < 0.05).Conclusion: By plasma electrolytic oxide the porous zinc-incorporated coating material could effectively promote the osteoblast adhesion in the surface of the Joint prosthesis.The proliferation and differentiation of MG63 cells may be related to the coating material release of zinc ions.It Showed that the porous nano the coating has strong activity to lead to bone-formation by plasma electrolytic oxide doped zinc which was in the joint prosthesis.It can promote the bone bonding and the bone ingrowth with the host bone tissue to the joint prosthesis,Which will be conformed to the requirements of the development of the new joint prosthesis materials.Part III The antibacterial property of porous zinc-incorporated coating prepared by plasma electrolytic oxidationObjective: To explore the antibacterial property of porous zinc-incorporated coating prepared by plasma electrolytic oxidation.Method: The Zn-Ti O2 sample was as the experimental group,with the Ti O2 group as the control one,which would be inoculated development respectively,Escherichia coli(ATCC25922)and Staphylococcus aureus strains(ATCC25923)were as the experimental strains to study.According to the bacteriostatic ring method(Halo),which was the antibacterial performance of qualitative tests;The plate count method was used to be the antibacterial properties of quantitative test;The fluorescent staining method was used to evaluate two groups of sample to the adhesion of bacteria sterilization ability.Result: According to the bacteriostatic ring;after twenty-four hours,it could see that the coating had been obvious widely around the trace of bacteriostatic ring in the Zn-Ti O2 group.According to the plate count method: In the seven day,the Ti O2 group had no antiseptic effect,bacteria growth and reproduction.The Zn-Ti O2 group for escherichia coli and staphylococcus aureus showed the strong sterilization ability;the Zn-Ti O2 group in 1,3,5,7days for staphylococcus aureus antibacterial rate reached 98.94%,83.76%,83.76% and 77.47% respectively;For e.coli antibacterial rate reached 96.95%,86.35%,82.96% and 72.98% respectively,and their antibacterial ability decreased with the extension of time.Fluorescent staining observation: In the one day,the Ti O2 group which adhered to the surface of the bacteria was mostly live and the Zn-Ti O2 activity of surface adhesion of bacteria have been lost.Conclusion: By plasma electrolytic oxide the porous zinc-incorporated coating has good antibacterial property to the staphylococcus aureus and e.coli.It can be used as a new kind of method to call for the preparation of the joint implants.