Ruthenium(II) polypyridyl complexes as emerging photosensitisers for antibacterial photodynamic therapy

J Inorg Biochem. 2024 Jan:250:112425. doi: 10.1016/j.jinorgbio.2023.112425. Epub 2023 Nov 7.

Abstract

Photodynamic therapy (PDT) has recently emerged as a potential valuable alternative to treat microbial infections. In PDT, singlet oxygen is generated in the presence of photosensitisers and oxygen under light irradiation of a specific wavelength, causing cytotoxic damage to bacteria. This review highlights different generations of photosensitisers and the common characteristics of ideal photosensitisers. It also focuses on the emergence of ruthenium and more specifically on Ru(II) polypyridyl complexes as metal-based photosensitisers used in antimicrobial photodynamic therapy (aPDT). Their photochemical and photophysical properties as well as structures are discussed while relating them to their phototoxicity. The use of Ru(II) complexes with recent advancements such as nanoformulations, combinatory therapy and photothermal therapy to improve on previous shortcomings of the complexes are outlined. Future perspectives of these complexes used in two-photon PDT, photoacoustic imaging and sonotherapy are also discussed. This review covers the literature published from 2017 to 2023.

Keywords: Antibacterial; Metals in medicine; Photodynamic therapy; Photosensitisers; Ruthenium(II) polypyridyl complexes.

Publication types

  • Review
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Anti-Bacterial Agents / pharmacology
  • Coordination Complexes* / chemistry
  • Coordination Complexes* / pharmacology
  • Photochemotherapy* / methods
  • Photosensitizing Agents / chemistry
  • Photosensitizing Agents / pharmacology
  • Photosensitizing Agents / therapeutic use
  • Ruthenium* / chemistry
  • Ruthenium* / pharmacology

Substances

  • Photosensitizing Agents
  • Ruthenium
  • Coordination Complexes
  • Anti-Bacterial Agents