An ESIPT active coumarin-diphenyl azine-based AIEgen: Nanomolar Cu2+ ion sensing, Latent Fingerprinting, live-cell imaging, and real sample analysis
Abhinav Jain, Soumik De, Pranjal Saraswat, Jebiti Haribabu, Juan F. Santibáñez, Pranjit Barman
Abstract
Designing economical and sensitive chemosensors for detecting important metal ions, like Cu 2+ ions, is essential and remains a hot topic worldwide. In this investigation, we extended our investigation to design a specific diphenyl-azine-based skeletal system for the selective and sensitive detection of Cu 2+ ions. We reported a coumarin-diphenyl-azine-based AIEgen (C-1) using an improvised methodology with a large Stoke's shift (∼245 nm) for precisely sensing copper ions in solid, solution, and biological cells. The AIE-ESIPT properties of C-1 were validated using various sophisticated techniques. C-1 was found to be a promising selective and sensitive sensor of Cu 2+ ions (nanomolar LOD value ∼10.38 nM) via colorimetric and TURN OFF fluorometric ways. The practical applicability of C-1 was analyzed via real-time estimation of copper ions in water samples (obtained from three varied locations) and in biological samples (urine and serum). The satisfactory recovery with a low RSD value indicates the potential of C-1 in detecting copper ions in actual samples. Estimating copper ions in urine and blood samples demonstrates the usefulness of C-1 in diagnosing disorders like Wilson's disease, which is caused by high concentrations of copper ions in the body. Additionally, we have detected Cu 2+ ions in live cells (HeLa cells) and carried out Latent Fingerprinting (Level 1 and Level 2) to validate its versatility in physiological and forensic applications. Overall, the proposed C-1 AIEgen is an ultrasensitive Cu 2+ ions sensor with innumerable applications in the physical world.