Use of the catalytic complex TiO₂/red cabbage anthocyanins to reduce the biofilm formation by planktonic bacteria

The bacterial cells dwelling within the biofilm usually develop resistance against common disinfectants. In this current study, to improve the effectiveness of photocatalytic treatment, a natural sensitizer in combination with unsupported titanium dioxide nanoparticles (TiO₂-NPs) was used to optimize the absorbance of NPs in the visible region and, to enhance the catalytic activity of the semiconductor. Different kinetic parameters were determined according to the first-order and the biphasic models to evaluate the ability of tested bacteria to form biofilm under different photocatalytic treatment conditions. As a result, the addition of red cabbage anthocyanins (RCA) as photosensitizer allows the enhancement of biocide activity of TiO₂-NPs and the reduction of biofilm formation by tested bacteria.