Leveraging bacterial survival mechanism for targeting and photodynamic inactivation of bacterial biofilms with red natural AIEgen

Abstract

Different from bacterial individuals, bacteria that live in a multicellular lifestyle with biofilm protection exert more severe and harmful attacks on human health. Such bacterial communities are hard to tackle with external agents, including antibiotics and bactericides. Therefore, developing versatile agents to detect and prevent bacterial biofilm is a simultaneously urgent yet challenging task. Herein, we report a naturally occurring red aggregation-induced emission luminogen (AIEgen), Tanshinone IIA, which is capable of specifically targeting bacterial biofilms, remarkably promoting bacterial aggregation, as well as effectively eliminating biofilm bacteria by means of photodynamic therapy. By conveying the concept of utilizing natural resources to battle environmental bacterial problems, this work demonstrates the ability of natural red-emissive AIEgen as a simple, cost-effective, bacterial biofilm-targeting and -erasing dual-functional agent, as well as providing a blueprint for a new direction of innovating environmental bactericides. • A naturally occurring red-emitting aggregation-induced emission luminogen is exploited • Targeting specificity to bacterial biofilm and promotion of bacterial aggregation • Effective elimination of biofilm bacteria by photodynamic therapy • New concept of natural resources as a simple and efficient biofilm inactivation agent Exploring versatile materials for simultaneous bacterial biofilm detection and inactivation is challenging. Lee et al. report a red-emissive natural AIEgen called Tanshinone IIA and its applications in biofilm staining, bacterial aggregation, and photodynamic bacterial inactivation. The study provides insights for fluorescent nano-aggregates and bacteria interaction.