E. coli Bacteriostatic Action Using TiO₂ Photocatalytic Reactions

Abstract

This experimental research comparatively investigates the Escherichia coli (E. coli) bacterial inactivation of the TiO 2 photocatalytic thin films fabricated by the sol-gel dip-coating (SG) and low-temperature spray-coating (SP) techniques, with low-intensity (12 μW·cm . Moreover, the essential physical characteristics of the SG-TiO 2 and SP-TiO 2 photocatalytic thin films were determined prior to the experimental bacterial inactivation. The findings showed that both photocatalytic thin films possessed the ideal physical characteristics, especially the SP-TiO 2 thin film. In addition, the viable cell counts, the cell morphology, and the bioluminescence-based adenosine triphosphate (ATP) indicated that both SG-TiO 2 and SP-TiO 2 thin films under UVA could effectively inhibit the proliferation of the E. coli cells in both NB and 0.85% NaCl.

Preliminary Study on Light-Activated Antimicrobial Agents as Photocatalytic Method for Protection of Surfaces with Increased Risk of Infections

“…(2017) demonstrated, for the first time, the effectiveness of the light-activated antimicrobial surface against yeast, viruses, filamentous fungi, and fungus-like organisms [59]. Research results regarding the inactivation of Escherichia coli by photocatalysis involving TiO 2 nanoparticles alone or in transparent coatings (varnishes) were recently published [60,61]. The antibacterial activity of TiO 2 was evaluated through two types of experiments under UV irradiation: (i) in slurry with physiological water (stirred suspension); and (ii) in a drop deposited on a glass plate.…”

Effects of Initial Nitrate Concentrations and Photocatalyst Dosages on Ammonium Ion in Synthetic Wastewater Treated by Photocatalytic Reduction

“…Ag-TiO 2 Photocatalyst Preparation and Characteristics. In this research, 1.0%Ag-TiO 2 photocatalyst was prepared by composite colloid deposition under alkaline condition, following Doudrick et al [4,9] with minor modifications. In the experiment, 12 g of TiO 2 nanopowder was dispersed in 500 mL deionized water and purged with nitrogen gas (N 2 ) for 30 min to remove O 2 .…”

“…However, those light sources have disadvantages that include high energy consumption, potential human health hazard, and generating high heat [7,8]. For those reasons, the UVA light bulb is chosen for this process because it overcomes those disadvantages and is powerful enough for this process [9][10][11].…”

Recyclable ferroferric oxide@titanium dioxide@molybdenum disulfide with enhanced enzyme-like activity under visible light for effectively inhibiting the growth of drug-resistant bacteria in sewage

“…Titanium dioxide (TiO 2 ) is an interesting semiconductor material, which has been extensively studied for environmental applications due to its characteristics of chemical inertness, powerful oxidation capability, cost-effectiveness, and long-term stability against both light and chemical corrosion. 13 Its wide bandgap energy (E g ) of 3.0-3.2 eV enables the creation of electrons (e À ) and holes (h + ), as well as the absorption of UV radiation, thus providing favorable conditions for redox reactions. 14,15 Many attempts, including the use of surface deposition, [16][17][18][19] ion doping, [20][21][22][23] and heterojunction methods corresponding to fast electron-hole separation, 24 have been made to increase the photocatalytic effectiveness of TiO 2 -based catalysts.…”