Aggregation-Induced Emission Active Metal-Free Chemosensing Platform for Highly Selective Turn-On Sensing and Bioimaging of Pyrophosphate Anion

Abstract

We report the synthesis of a metal-free chemosensor for highly selective sensing of pyrophosphate (PPi) anion in physiological medium. The novel phenylbenzimidazole functionalized imine containing chemosensor (L; [2,6-bis(((4-(1H-benzo[d]imidazol-2-yl)phenyl)imino) methyl)-4 methyl phenol]) could sense PPi anion through "turn-on" colorimetric and fluorimetric responses in a very competitive environment. The overall sensing mechanism is based on the aggregation-induced emission (AIE) phenomenon. Moreover, a real time in-field device application was demonstrated by sensing PPi in paper strips coated with L. Interestingly, detection of intracellular PPi ions in model human cells could also be possible by fluorescence microscopic studies without any toxicity to these cells.

Optical Sensing (Nano)Materials Based on Benzimidazole Derivatives

“…AIE or AIEE (aggregation-induced emission enhancement) can be observed in the so called 'poor' solvents, in crystalline or powder forms. With that in mind, benzimidazolebased fluorophores capable of emitting intense fluorescence in the aggregated form (AIE emitters) can also be classified as novel sensing materials [55][56][57][58]. For example, self-assembled nanoaggregates of benzimidazole-based acrylonitrile derivative are presented as sensing system for pH, based on aggregation-deaggregation mechanism and aggregation-induced emission (AIE) [59].…”

“…The aggregation and emission are pH switchable and fully-reversible. Gogoi et al presented a novel AIE system based on a benzimidazole derivative for the detection of pyrophosphate (PPi) (Figure 4) [56]. The benzimidazole moiety has a functional role in assembling aggregate structures and the recognition of Ppi.…”

Pyrophosphate Prompted Aggregation‐Induced Emission: Chemosensor Studies, Cell Imaging, Cytotoxicity, and Hydrolysis of the Phosphoester Bond with Alkaline Phosphatase

“…To scrutinize the reversible binding of R1 with PPi, the calcium ions have been employed. This is because the Ca(II) has strong affinity to form interaction with pyrophosphate . On addition of 0 ‐ 10 µ m of Ca 2+ to R1 + PPi aggregates, the quenching in the fluorescence intensity was observed, this was due to disruption of R1 + PPi aggregates and formation of calcium pyrophosphate complex.…”

Nanomolar Zn(ii) sensing and subsequent PPi detection in physiological medium and live cells with a benzothiazole functionalized chemosensor

“…[46][47][48][49] Based on the aforementioned premise, herein we report the synthesis and photophysical properties of a benzothiazole based dipodal Schiff base chemosensor L 1 (2,6-bis((E)-(2-(benzothiazol-2-yl)hydrazono)methyl)-4-methylphenol). [46][47][48][49] Based on the aforementioned premise, herein we report the synthesis and photophysical properties of a benzothiazole based dipodal Schiff base chemosensor L 1 (2,6-bis((E)-(2-(benzothiazol-2-yl)hydrazono)methyl)-4-methylphenol).…”