Nanotexturization of Ti-based implants in simulated body fluid: Influence of synthesis parameters on coating properties and kinetics of drug release

In the present study, TiO2NT coatings grown on simulated body fluid-based electrolyte were investigated as drug delivery devices. Nanotubes (NTs) were grown over commercially pure Ti and Ti6Al4V alloy. Morphology analysis showed that NTs in alloy samples present an inner diameter of 10 nm smaller in average than NTs grown over pure Ti. The surface wettability in water decreased with the anodizing time for both substrates. The application of coatings as drug delivery devices has been studied through the incorporation of ciprofloxacin. To control the drug release, collagen was used as the diffusional barrier. It was observed the drug release follows a Fick's kinetics. Bioactivity assays showed the absence of hemolytic activity. The concentration of the drug during the release interval remained below the toxic concentration limit, presenting a bacteriostatic activity. All coatings prepared presented a high antibacterial activity, being the area of inhibition of bacterial growth above 13 times the area of the implant.