Degradation of Candida albicans on TiO2 and Ag-TiO2 thin films prepared by sol–gel and nanosuspensions

In this study, both suspensions and thin films of TiO2 and silver loaded TiO2 (Ag-TiO2) were used in the photocatalytic degradation/disinfection of C. albicans. In the case of thin films coated materials, both microscope slides and steel pieces of similar dimensions were dip coated using sol–gel solutions prepared from titanium isopropoxide. Surface analysis of the materials confirmed that thin film formation had been succesful. After set periods of irradiation in the presence of suspension or thin film coated material, 10 lL aliquots of the solution were withdrawn and directly cultivated on sabouraud dextrose agar for 24 h at 37 �C. The number of living colonies was counted. The results show that both the suspensions and the thin films displayed superior antimicrobial properties towards C. albicans. In particular the Ag-TiO2 catalyst was extremely active even in the dark, for disinfection of C. albicans. The degradation percentage over TiO2 and Ag-TiO2 thin films coated on the steel substrate was higher than those coated on glass achieving 80 and 97.9%, respectively, using the 365 nm, near visible region light source.