Photo-Responsive Antimicrobial Nanocoatings in the Nosocomial Setting

Healthcare-associated infections (HAIs) are a source of constant risk for inpatients and healthcare workers and a serious challenge to human health services worldwide. Common surfaces, such as doorknobs, tables, and bedrails, can become contaminated and develop into a reservoir of pathogens; thus, common surfaces can play an important role in the fomite-mediated pathway through which HAIs are transmitted. Non-critical disinfection techniques are common practice in the nosocomial setting, aiming to reduce the bioburden of common surfaces and prevent the spread of HAIs. However, these techniques are limited by factors such as the need for frequent disinfectant reapplication and the potential recontamination that can occur at any moment after cleaning. Light-activated antimicrobial nanocoatings are an interesting alternative to overcome these issues, since these nanocoatings can confer self-disinfection capacities to nosocomial common surfaces, to supplement non-critical disinfection. Thus, this review aims to discuss the relevance of fomites and gaps in common disinfection strategies that favor the propagation of HAIs. In addition, nanotechnology-based antimicrobial coatings are considered, along with strategies for nanoparticle-based antimicrobial coating development. Furthermore, the use of titanium oxide nanoparticles to formulate photo-responsive antimicrobial nanocomposites/nanocoatings and concerns related to toxicity, environmental fate, and bacterial resistance development are discussed. Finally, emerging photo-responsive antimicrobial nanotechnologies and future perspectives are considered.