A ratiometric fluorescent system for carboxylesterase detection with AIE dots as FRET donors

A ratiometric fluorescent system for CaE detection with AIE dots as the FRET donors was designed. Upon enzymatic reaction, electrostatic interaction between the cationic TPE-N+ dots and the enzymatic reaction product - the negatively charged fluorescein molecules allows the FRET process to proceed, thus affording the ratiometric fluorescence CaE assay.