Light-activated antimicrobial coatings: the great potential of organic photosensitizers

Abstract

Contamination of inanimate surfaces with microorganisms is considered one of the routes for transmission of pathogens, which is a matter of concern not only in healthcare-related facilities, but also in public areas. Durable antimicrobial coatings have emerged as the one of most promising strategies for reducing the accumulation of microorganisms on high-touch surfaces. Light-activated antimicrobial layers are of particular interest for such a purpose, as they generate singlet oxygen and other reactive oxygen species that are effective against a broad spectrum of bacteria, viruses, and fungi. In this review, the antimicrobial coatings containing organic photosensitizers are discussed, focusing on the recent advances in the strategies for PSs' immobilization on solid surfaces. The review attempts to assess the advantages and limitations of those systems, and the challenges that still need to be overcome.