Precise control for the aggregation and deaggregation with the aid of a tetraphenylethylene derivative: Luminescence modulation and sensing performance

Abstract The versatility of the organic fluorophores enables us to track its emission curves and sharp luminescence changes under controllable conditions. A tetraphenylethylene-based fluorescent probe (1-methyl-4-(4-(1,2,2-triphenylvinyl)styryl)pyridin-1-ium iodide, abbreviated as TPE-py-I) has been synthesized and yields efficient red emission in organic phase (DMSO). The incorporation of ClO− in its DMSO solution triggers efficient “on-off” quenching effect due to ions exchange from iodide to hypochlorite. The inactivation of the original red luminescence can be also realized by the addition of water and the typical aggregation-caused-quenching (ACQ) has been observed. Unexpectedly, such ACQ process will be suppressed and lead to an aggregation-induced-emission (AIE) effect, providing distinct fluorescent read-out from pale-red to bright yellow in the presence of hypochlorite. The limit of detection (LOD) has been calculated to be 0.25 μM via ratiometric operation with an excellent linear range from 1 μM to 50 μM. This non-invasive and in-situ detection of ClO− via AIE modes can be employed as an indicator for the evaluation of ions responses in real environments.