Design of Photosensitizing Agents for Targeted Antimicrobial Photodynamic Therapy

• Published in: Molecules (Basel, Switzerland) Vol. 25; no. 22; p. 5239
• Main Authors: Klausen, Maxime, Ucuncu, Muhammed, Bradley, Mark
• Format: Journal Article
• Language: English
• Published: Switzerland MDPI 10.11.2020; MDPI AG
• Subjects: Animals; Anti-Infective Agents - pharmacology; antimicrobial peptides; antimicrobial resistance; Humans; Hydrogen-Ion Concentration; Liposomes - chemistry; Mice; Micelles; nanomaterials; Oligosaccharides - chemistry; Peptides - chemistry; Photochemotherapy - methods; photodynamic therapy; photosensitizer; Photosensitizing Agents - chemical synthesis; Photosensitizing Agents - pharmacology; Polymers - chemistry; reactive oxygen species; Review; Singlet Oxygen - chemistry; Static Electricity; Superoxides; nanomaterials; antimicrobial resistance; photodynamic therapy; antimicrobial peptides; reactive oxygen species; photosensitizer
• ISSN: 1420-3049; 1420-3049
• DOI: 10.3390/molecules25225239

Photodynamic inactivation of microorganisms has gained substantial attention due to its unique mode of action, in which pathogens are unable to generate resistance, and due to the fact that it can be applied in a minimally invasive manner. In photodynamic therapy (PDT), a non-toxic photosensitizer (PS) is activated by a specific wavelength of light and generates highly cytotoxic reactive oxygen species (ROS) such as superoxide (O , type-I mechanism) or singlet oxygen ( O *, type-II mechanism). Although it offers many advantages over conventional treatment methods, ROS-mediated microbial killing is often faced with the issues of accessibility, poor selectivity and off-target damage. Thus, several strategies have been employed to develop target-specific antimicrobial PDT (aPDT). This includes conjugation of known PS building-blocks to either non-specific cationic moieties or target-specific antibiotics and antimicrobial peptides, or combining them with targeting nanomaterials. In this review, we summarise these general strategies and related challenges, and highlight recent developments in targeted aPDT.