Tunable Functionality and toxicity studies of Titanium Dioxide Nanotube Layers

TL;DR

This study developed scalable titanium dioxide nanotube layers with tunable properties, characterized their structure and wettability, assessed their photocatalytic activity, and evaluated their toxicity using a protozoan model, finding no adverse biological effects.

Contribution

The paper presents a cost-effective method to produce titanium dioxide nanotube layers with adjustable functionality and demonstrates their photocatalytic efficiency and biocompatibility.

Findings

Higher photocatalytic activity at increased current density.

Surface wettability varies with anodization time.

No observed toxicity effects on T. pyriformis.

Abstract

In this work, we have developed economic process to elaborate scalable titanium dioxide nanotube layers which show a tunable functionality. The titanium dioxide nanotube layers was prepared by electrochemical anodization of Ti foil in 0.4 wt% hydrofluoric acid solution. The nanotube layers structure and morphology were characterized using x-ray diffraction and scanning electron microscopy. The surface topography and wettability was studied according to the anodization time. The sample synthesized while the current density reached a local minimum displayed higher contact angle. Beyond this point, the contact angles decrease with the anodization time. Photo-degradation of acid orange 7 in aqueous solution was used as a probe to assess the photo-catalytic activity of titanium dioxide nanotube layers under UV irradiation. We obtained better photocatalitic activity for the sample elaborate at higher current density. Finally we use the Ciliated Protozoan T. pyriformis, an alternative cell model used for in vitro toxicity studies, to predict the toxicity of titanium dioxide nanotube layers in biological system. We did not observe any characteristic effect in the presence of the titanium dioxide nanotube layers on two physiological parameters related to this organism, non-specific esterases activity and population growth rate.