Seeing is Believing: Facile Amphiphilic AIEgen Unveils Selective and Ultrafast Wash-Free Dead Cell Imaging

Abstract

The differentiation between live and dead cells is essential for both pharmacological and pathological research. However, current fluorescence probes face challenges due to their cumbersome methodologies and a lack of real-time imaging capabilities. In this study, we introduce an amphiphilic aggregation-induced emission luminogen (AIEgen) that incorporates two ammonium salts with the AIE building block of squaraine dyes. The resulting compound, SQ-N, exhibits negligible emission in aqueous and organic solvents as well as in the solid state, while displaying vivid orange fluorescence specifically in glycerol. This AIEgen has demonstrated the ability to selectively ‘light up’ dead cells with rapid, wash-free kinetics within seconds at room temperature, thereby presenting an ultrafast and user-friendly staining protocol. Additionally, the superior biocompatibility, long-term retention, and photostability of SQ-N render it more suitable for real-time and in situ monitoring of cell viability, thus serving as an effective alternative to commercial probes. Our work offers new insights into the amphiphilic AIEgen and its potential for the development of cellular imaging probes.