Photoreactive Coating Material as an Effective and Durable Antimicrobial Composite in Reducing Bacterial Load on Surfaces in Livestock

Abstract

Titanium dioxide (TiO2) is a well-known photocatalytic compound that can be used to effectively reduce the presence of pathogens in human and animal hospitals via ROS release. The aim of this study was to investigate the efficacy of a polymer-based composite layer containing TiO2 and zinc oxide (ZnO) against Escherichia coli (E. coli) of animal origin. We showed that the photocatalyst coating caused a significant (p < 0.001) reduction in pathogen numbers compared to the control with an average reduction of 94% over 30 min. We used six light sources of different wattages (4 W, 7 W, 9 W, 12 W, 18 W, 36 W) at six distances (35 cm, 100 cm, 150 cm, 200 cm, 250 cm, 300 cm). Samples (n = 2160) were taken in the 36 settings and showed no significant difference in efficacy between light intensity and distance. We also investigated the influence of organic contaminant that resulted in lower activity as well as the effect of a water jet and a high-pressure device on the antibacterial activity. We found that the latter completely removed the coating from the surface, which significantly (p < 0.0001) reduced its antibacterial potential. As a conclusion, light intensity and distance does not reduce the efficacy of the polymer, but the presence of organic contaminants does.

Anti-Infective and Toxicity Properties of Carbon Based Materials: Graphene and Functionalized Carbon Nanotubes

“…Therefore, toxicity evaluation is very critical for the commercialization of CNTs as novel antimicrobial agents [131][132][133]. [134] TiO 2 (Titanium oxide) is one of the most expensive and widely used photocatalysts with bactericidal properties. Researchers tend to design a combination of TiO 2 and ZnO (Zinc oxide) and semiconductors to achieve high photosensitivity, redox potential, and photocatalytic activity with lower cost and toxicity [134].…”

“…[134] TiO 2 (Titanium oxide) is one of the most expensive and widely used photocatalysts with bactericidal properties. Researchers tend to design a combination of TiO 2 and ZnO (Zinc oxide) and semiconductors to achieve high photosensitivity, redox potential, and photocatalytic activity with lower cost and toxicity [134]. Researchers evaluated the stepby-step inactivation of E. coli by photocatalysis.…”

“…Takao et al suggested that the presence of a peptidoglycan layer increases the bactericide effect of photocatalysis. Rodríguez-González et al also described the existence of lesions in the bacterial cell wall caused by ROS molecules and metal particles [134]. Kerek et al showed that the photocatalyst coating of graphene with TiO 2 and ZnO caused a significant (p < 0.001) reduction in pathogen numbers compared to the control.…”

“…Kerek et al showed that the photocatalyst coating of graphene with TiO 2 and ZnO caused a significant (p < 0.001) reduction in pathogen numbers compared to the control. It is assumed that photocatalysis and titanium coatings of carbon-based material (CNTs and Graphene) would be a potential alternative to fighting antimicrobial resistance, which has significant bacterial reduction capacity against environmental pathogens [134].…”