The bactericidal and mildew-proof activity of a TiO2-chitosan composite

The current study combines the TiO2 photo-catalysis and the bactericidal activity of chitosan (CS), incorporated into a novel bactericidal and mildew-proof fabric (BMF) through immobilization of TiO2-CS composite on cotton fibers. The optimum preparation conditions of BMF were determined. The bactericidal activities of samples were evaluated by the inactivation of three strains, Escherichia coli, Staphylococcus aureus and A. niger. The results showed that the bactericidal yields of BMF for E. coli, S. aureus and A. niger reached respectively 99.9%, 99.9% and 97.4% after 12 h visible light irradiation. The long-lasting bactericidal ability of BMF is stable due to most of E. coli, S. aureus and A. niger being completely killed or broken by the micrograph of cell debris. The UV-vis transmission spectra show a strong absorption that spans the visible light spectral region. A possible explanation of the photo-catalytic action of BMF is proposed.