Hydrothermally synthesized titanium/hydroxyapatite as photoactive and antibacterial biomaterial

The present work investigated hydrothermal synthesis of titanium/hydroxyapatite (Ti/HA) nanocomposite at varied Ti content. The synthesis was performed by coprecipitation method using CaO, ammonium dihydrogen phosphate and titanium oxide chloride precursor with the additional cetyl trimethyl ammonium chloride as templating agent, followed by hydrothermal treatment at 150 °C. The derived materials were characterized by x-ray diffraction, x-ray photoelectron spectroscopy, scanning electron microscopy, transmission electron microscopy analyses. The photocatalytic properties of materials were tested on methyl violet (MV) photocatalytic oxidation, meanwhile the antibacterial testing was performed against Escherichia coli, Staphylococcus aureus, Klebsiella pneumonia, and Streptococcus pyogenes. In addition, cytotoxicity evaluation of the materials as potential biomaterial was also conducted. The results showed that physicochemical character of Ti/HA exhibits exhibit the excellent properties to be photocatalyst along with antibacterial activity. From the detail study of effect of varied titanium content ranging from 5 to 10 %wt., the increasing crystallite size of anatase phase of about 25.81 nm and 38.22 nm for Ti content of 5 and 10 % wt., respectively. In other side, the band gap energy value increases as the increasing Ti content, i.e. the values are 3.08; 3.18; and 3.20 eV for Ti content of 5, 10, 20 % wt., respectively. The band gap energy is correlated with the photocatalytic activity which the highest MV degradation was 96.46% over Ti/HA with 20% wt. of Ti (Ti20/HA). The nanocomposites also express the antibacterial activity with comparable minimum inhibitory concentration (MIC) with other similar Ti/HA nanocomposites. The MIC values of Ti20/HA against E. coli, S. aureus, K. pneumonia, and S. pyogenes are 25; 25; 50 and 50 μg/mL, respectively. In addition, the cytotoxicity test revealed the potency to be a biomimetic material as shown by severe toxicity.