Photoacidolysis-Mediated Iridium(III) Complex for Photoactive Antibacterial Therapy

Photoactive antibacterial therapy is one of the novel
therapeutic
methods that has great application potential and prospects for curbing
bacterial infections. In this work, a photoactivated iridium complex
(Ir–Cl) is synthesized for photoactive antibacterial
research. Ir–Cl exhibits photoacidolysis, which
can generate H+ and be converted into a photolysis product Ir–OH under blue light irradiation. At the meantime,
this process is accompanied by 1O2 generation.
Notably, Ir–Cl can selectively permeate S. aureus and exhibit excellent photoactive antibacterial
activity. Mechanism studies show that Ir–Cl can
ablate bacterial membranes and biofilms under light irradiation. Metabolomics
analysis proves that Ir–Cl with light exposure
mainly disturbs some amino acids’ degradation (e.g., valine,
leucine, isoleucine, arginine) and pyrimidine metabolism, which indirectly
causes the ablation of biofilms and ultimately produces irreversible
damage to S. aureus. This work provides guidance
for metal complexes in antibacterial application.