Triphenylphosphonium cation: A valuable functional group for antimicrobial photodynamic therapy

Abstract

Light-mediated killing of pathogens by cationic photosensitisers is a promising antimicrobial approach that avoids the development of resistance inherent to the use of antimicrobials. In this study, we demonstrate that modification of different photosensitisers with the triphenylphosphonium cation yields derivatives with excellent photoantimicrobial activity against Gram-positive bacteria (ie, Staphylococcus aureus and Enterococcus faecalis). Thus, the triphenylphosphonium functional group should be considered for the development of photoantimicrobials for the selective killing of Gram-positive bacteria in the presence of Gram-negative species.

Keywords: antibiotic resistance; antimicrobial photodynamic therapy; cationic photosensitisers; phenalenone; photoantimicrobials; reactive oxygen species; singlet oxygen; triphenylphosphonium.