Influence of tunable diameter on the electrochemical behavior and antibacterial activity of titania nanotube arrays for biomedical applications

Abstract

The conventional bone implants based on titanium metals requires long time treatment process. Since the osteoporosis become a common chronic disease, rapid osseointegration of bone implants will help to shorten the period of treatment and enhance the comfort of patients. The fabrication of nanostructured bone implants resembles like native bone promotes rapid osseointegration. Here we studied the influence of tunable diameter of titanium nanotube arrays for bio implant applications. A facile electrochemical anodization process was performed to fabricate array of nanotube structures on Ti surface using the mixture of glycerol and ammonium fluoride electrolyte containing water. The diameter of the nanotubes was controlled by varying water content and studied their surface morphology, corrosion behavior and antibacterial activity. The morphological studies revealed an increase in nanotube diameter and reduction in length with increasing addition of water. X-ray diffraction analysis showed that the intensity of anatase peak increases with the addition of water. Wettability measurements revealed that the formed titania nanotubes were hydrophilic in nature. The study examined the adhesion of Staphylococcus aureus on substrate and anodized specimens by bacterial viability test and the results showed that the anodized specimens showed higher percentage of inhibition compared to substrate. The decrease in icorr value observed for TNTA specimens obtained from the potentiodynamic polarization studies was attributed to the variation in tube diameter and intertubular spaces with varying water content. The results of electrochemical impedance spectroscopy studies in Hanks' solution also have endorsed the structural changes occurred in the nanotube morphology by the variation of water content influenced the electrochemical properties.