A new nano-TiO2 immobilized biodegradable polymer with self-cleaning properties

This study concentrated on the direct immobilization of anatase nano titanium dioxide particles (TiO2, 10nm particle size) into or onto a biodegradable polymer, polycaprolactone, by solvent-cast processes. The self-cleaning, namely photocatalytic properties of the produced materials were tested by photocatalytic removal of methylene blue as model compound and antimicrobial properties were investigated using Candida albicans as model microorganism. Produced TiO2 immobilized polymer successfully removed methylene blue (MB, 1×10−5 M) from aqueous solution without additional pH arrangement employing a UV-A light (365 nm) source. Almost 83.2% of dye was removed or decomposed by 5 wt% TiO2 immobilized into PCL (0.08 g) and removal percentage reached to 94.2% with 5 wt% TiO2 immobilized onto PCL after a 150 min exposure period. Although removal percentage decrease with increased ionic strength and usage of a visible light source, produced materials were still effective. TiO2 immobilized onto PCL (5 wt%) was quite effective killing almost 54% of C. albicans (2×106 CFU/mL) after only 60 min exposure with a near visible light source. Control experiments employing PCL alone in the presence and absence of light were ineffective under the same condition.