An aggregation-induced emissive pyridoxal derived tetradentate Schiff base for the fluorescence turn-off sensing of copper(ii) in an aqueous medium

Abstract

In this study, a tetradentate Schiff base ligand L was synthesized by condensing o-phenylenediamine with two moles of pyridoxal. The solution of L in EtOH/DMSO showed aggregation-induced emission (AIE) behaviour...

Probing Biothiols Using a Red‐Emitting Pyridoxal Derivative by Adopting Copper(II) Displacement Approach and Cell Imaging

“…Schiff base containing o ‐hydroxy group generally undergo enol‐keto tautomerisation due to the internal proton transfer process, which is predominantly responsible for the change of optical and electronic properties of L [33–34] . Also, the enol‐keto tautomerisation in Schiff bases greatly affected with the change in the solvent polarity.…”

“…The selectivity of AIEgen L towards Cu 2+ can also be visually detected from the quenching of the red‐emitting fluorescent color. It is expected that the formation of L‐Cu 2+ complex quenched the fluorescence of L at 608 nm due to the electron transfer from the excited AIEgen L to the paramagnetic Cu 2+ [32,34] . In addition, the ESIPT process may be supressed due to the chelation‐enhanced fluorescence quenching (CHEQ) effect.…”

“…It is expected that the formation of L-Cu 2 + complex quenched the fluorescence of L at 608 nm due to the electron transfer from the excited AIEgen L to the paramagnetic Cu 2 + . [32,34] In addition, the ESIPT process may be supressed due to the chelation-enhanced fluorescence quenching (CHEQ) effect. Subsequenly, the compititive experiments were conducted to examine the interference of other metal ions.…”

Fluorescence ‘turn-on’ probe for nanomolar Zn(ii) detection in living cells and environmental samples

“…[25][26][27][28][29][30][31][32][33][34][35][36][37][38][39] However, among these methods, fluorescence-quenching-based probes are not suitable for analyzing intracellular analytes. [40][41][42][43] In this context, a fluorescence turn-on chemosensor with high sensitivity and specificity is crucial for detecting intracellular Zn 2+ . Several Zn 2+ -selective chromo-fluorogenic probes have been reported in the literature.…”

An ESIPT-based fluorescent probe for the detection of multiple analytes and a facile approach to discriminate between arsenate and pyrophosphate in water

“…On the other hand, exposure of a specific analyte allows H-bond and keto form, unlocking the ESIPT process. Most of the AIE and ESIPT based fluorescent sensors known to detect either one individual analyte or dual responsive probes for two analytes, rather than sensing multiple analytes in parallel [11]. Dual responsive probes contain two distinct sensing groups for each analyte [12].…”