No abstract

Multidrug resistance (MDR) bacteria pose a serious threat to human health. The development of alternative treatment modalities and therapeutic agents for treating MDR bacteria-caused infections remains a global challenge. Herein, a series of near-infrared (NIR) anion-𝝅 + photosensitizers featuring aggregation-induced emission (AIE-PSs) are rationally designed and successfully developed for broad-spectrum MDR bacteria eradication. Due to the strong intramolecular charge transfer (ICT) and enhanced highly efficient intersystem crossing (ISC), these electron-rich anion-𝝅 + AIE-PSs show boosted type I reactive oxygen species (ROS) generation capability involving hydroxyl radicals and superoxide anion radicals, and up to 99% photodynamic killing efficacy is achieved for both Methicillin-resistant Staphylococcus aureus (MRSA) and multidrug resistant Escherichia coli (MDR E. coli) under a low dose white light irradiation (16 mW cm −2 ). In vivo experiments confirm that one of these AIE-PSs exhibit excellent therapeutic performance in curing MRSA or MDR E. coli-infected wounds with negligible side-effects. The study would thus provide useful guidance for the rational design of high-performance type I AIE-PSs to overcome antibiotic resistance.

Novel antibacterial agents are urgently needed to control the infections induced by multidrug‐resistant (MDR) bacteria. Herein, we rationally designed and facilely synthesized a new D‐π‐A type luminogen with strong red/near‐infrared fluorescence emission, great aggregation‐induced emission (AIE) features, and excellent reactive oxygen species (ROS) production. The newly developed molecule TTTh killed the methicillin‐resistant Staphylococcus aureus (MRSA) by triggering the ROS accumulation in bacteria and interrupting the membrane integrity. Moreover, TTTh specifically targeted the lysosomes and potentiated their maturation to accelerate the clearance of intracellular bacteria. Additionally, reduced bacterial burden and improved healing were observed in TTTh‐treated wounds with negligible side effects. Our study expands the biological design and application of AIE luminogens (AIEgens), and provides new insights into discovering novel antibacterial targets and agents.

Threats posed by recalcitrant bacterial biofilms have been continuously challenging the public health due to the dramatically magnified antibiotic resistance resulted from the complicated biofilm microenvironment. Urgent demands on effective biofilm combating have propelled the rapid exploration of high‐performance antibiofilm systems. Thanks to the distinguished features of aggregation‐intensified fluorescence and aggregation‐enhanced generation of reactive oxygen species, aggregation‐induced emission luminogens (AIEgens) are becoming increasingly eye‐catching in the field of biofilm combating by serving as excellent fluorescence imaging probes or theranostic agents. This review aims to, for the first time, outline the current progress of AIEgens in bacterial biofilm imaging and antibiofilm theranostics. The up‐to‐date advancements of AIEgens in enzyme‐responsive biofilm imaging, discriminative imaging of Gram‐positive bacterial biofilm, as well as biofilm viability monitoring are summarized at first. Subsequently, the antiadhesion intervention‐mediated prevention of biofilm formation and photodynamic therapy‐involved eradication of preexisting biofilms are detailedly elucidated. Finally, a brief conclusion as well as a discussion on the current challenges and future expectations is presented.