Cationic Conjugated Oligomers for Efficient and Rapid Antibacterial Photodynamic Therapy via Both Type I and Type II Pathways

Comprehensive Summary Recently, photodynamic therapy (PDT) has attracted wide attention due to its less susceptibility to drug resistance, broad‐spectrum biocidal activity and biosafety in normal tissues. However, the traditional photosensitizers (PSs) face the disadvantage of poor therapeutic efficacy due to the requirement of an aerobic environment to generate 1 O 2 through Type ІI pathway. Herein, we designed and synthesized a novel cationic conjugated oligomer oligo(phenylene vinylene) (OPV) and studied its antibacterial photodynamic activity against both Gram‐negative Escherichia coli ( E. coli ) and Gram‐positive bacteria methicillin‐resistant Staphylococcus aureus (MRSA). Importantly, the OPV can rapidly produce reactive oxygen species (ROS) through double pathways, Type I and II mechanism under white light irradiation, and efficiently kill E. coli and MRSA at a nanomolar level. The dual type photosensitizing capability makes OPV promising for enhanced PDT to treat pathogens and tumors in complex environments.