Preparation Of The Orthopedic Titanium Plates With Iodine Coating And The Antimicrobial Test In Vitro

Background and Purpose: With the widespread use of internal fixation materials for fractures,the presence of bacterial biofilms on implants has attracted more and more attention due to the difficulty in eliminating bacteria attached with implants and the following infection.Because the surface of implants allows bacteria to grow and reproduce,implantation-related infection has become a major risk for orthopedic surgery.Therefore,the development of anti-infective internal fixation materials to prevent and treat implantation-ralated infection will have clinical advantages.The coating containing povidone iodine was prepared on titanium substrate by anodic oxidation technique,which was used to prevent and treat implant-related infection.It is of great clinical significance to prevent implant-associated infection.Methods: Coating Titanium Plate with povidone iodine by anodizing technique: 1.The experimental orthopedic titanium plate was dissected,polished,deoiled,cleaned and dried.2.Four different concentrations of povidone iodine electrolytes were prepared,the concentrations were 1000 ppm,2200ppm,3000 ppm and 4000 ppm respectively.3.A 2cm space lies between the anode titanium plate and cathode platinum plate,which wereconnected with wire.Set the 200 v voltage and 30 minutes for electrolysis as well as 25 ℃surrounding temperature for electrolyte..Flush the product with deionized water after reaction and Concussion with ultrasound for 10 minutes.Dry at room temperature.Determination of iodine content in titanium plates: the determination of the iodine content of titanium plates in different concentrations of polyvidone iodine electrolyte(1000ppm,2000 ppm,3000ppm,4000ppm)by EDS.Grouping for antimicrobial test: Control group: Ten polished titanium plates with no iodine coat.Experiment group:Group A: 10 titanium plates prepared in povidone iodine electrolyte with concentration of 1000ppm;Group B: 10 titanium plates prepared in povidone iodine electrolyte with concentration of 2000ppm;Group C: 10 titanium plates prepared in the solution of povidone iodine at concentration of 3000ppm;D group: 10 titanium plates prepared in the concentration of 4000 ppm in povidone iodine electrolyte.1* 106 cfu Escherichia coli is respectively inoculated on thess plates in 37 ℃ for 6 hours..Titanium plates were taken out with aseptic tweezers,the then washed with 20 ml saline.Collect the flushing fluid and then spread 100 ul flushing fluid on agar medium.Finally,the Agar medium was cultured in 37 ℃ incubator for 24 hours and the colony number was counted.Results: 1.The irregular structure on the surface of iodine coating titanium plate producted by electrophoresis could be observed by scanning electron microscope,which may result from corrosion of electrolyte Through changing experiment parameters,the iodine content could top 14% under the analysis of energy spectrometer 2..The number of colonies in the five groups was compared with that of the control group and each experimental group by lsd method.The p value of the five groups was less than 0.05,the difference was statistically significant.Conclusion: 1.The surface morphology of the iodine coating titanium prodcted by anodic xidation was observed by scanning electron microscope.Together with the results of analysis of energy spectrometer,We could quantitatively confirm iodine coating is successful even with a top 14 % content.2.According to results of antibacterial test on Escherichia coli in vitro,iodine coating titanium plate has showed t bacteriostatic effect on G-bacteria represented by Escherichia coli.