The Role of Structural Hydrophobicity on Cationic Amphiphilic Aggregation-Induced Emission Photosensitizer-Bacterial Interaction and Photodynamic Efficiency

The aggregation-induced emission photosensitizer (AIEPS) has stoodout as an alternative and competent candidate in bacterial theranostics,particularly with the use of cationic AIE PS in bacterial discriminationand elimination. Most reported work emphasizes the role of electrostaticinteraction between cationic AIE PS and negatively charged bacterialsurfaces, enabling broad applications from bacterial discriminationto bacterial killing. However, the underlying targeting mechanismand the design rationale of the cationic AIE PS for effective bacteriallabeling remain poorly investigated. In this Article, we designedand synthesized a series of cationic amphiphilic AIE PSs with differentcalculated log P values. Then, we systemically studiedthe relationship between the hydrophobicity variation of AIE PS andbacterial targeting outcomes, the dose of AIE PS needed to label variousspecies of bacteria, and their photodynamic antibacterial efficiency.The findings in this work provide a better understanding of the unclearAIE PS-bacterial interaction mechanism and some insights intothe structural design strategies of cationic amphiphilic AIE PS forbetter development in bacterial theranostics.