Amphiphilic gemini-iridium (III) complex for rapid and selective detection of picric acid in water and intracellular

Inspired by the structure and properties of gemini surfactant, a novel amphiphilic gemini-iridium complex (GIC-Ir) has been developed, which can spontaneously form vesicles by self-assembly and exhibit excellent dispersibility and high emission intensity in water. The emission of GIC-Ir can be rapidly and selectively quenched by picric acid (PA) due to the aromatic groups and two long-chain quaternary ammonium (QA) groups with positive charge, which endow GIC-Ir vesicles outstanding capability to capture negatively charged PA, and greatly promote the interaction between GIC-Ir and PA. Theoretical calculations and spectral studied indicated that the photoinduced electron transfer and resonance energy transfer may be responsible to the emission quenching. Furthermore, the real water samples and in vitro studies further prove that GIC-Ir can be used as a promising chemosensor for the detection of PA both in water and intracellular.