A two-photon probe for Al3+ in aqueous solution and its application in bioimaging

A simple hydrazone as a multianalyte (Cu2+, Al3+, Zn2+) sensor at different pH values and the resultant Al3+ complex as a sensor for F−

“…7 In general, Al 3+ prefers hard donor sites (e.g., O and N) in its coordination sphere because of its strong acidity, and the strong hydration of Al 3+ in aqueous media leads to its weak coordination ability. 8,9 Besides, the detection of Al 3+ can be easily interfered with by the matrix, leading to limited selectivity and sensitivity. [10][11][12] Thus, designing a selective and sensitive uorescence probe for Al 3+ in aqueous media remains a challenge.…”

A Highly Selective Fluorescent Chemosensor for Al3+ Based on 2,2’:6’,2”-Terpyridine with a Salicylal Schiff Base

“…3 Typically, metal ion chemosensors are composed of a metal binding unit and signaling unit, which enable the fluorescent chemosensors to coordinate with metal ions. Later on, fluorescent sensors based on a large number of metal binding units with different structures, including pyrazoline, 4 peptide, 5 salicylimine, 6 tetrazole, 7 triazole, 8 4,5-diazafluorene 9 and 2,2':6',2"-terpyridine (TPy) 10 have been developed. Among these receptors, 2,2':6',2"-terpyridine moiety is an ideal model for the construction of fluorescence sensors because of its excellent coordination ability with various metal ions.…”

Theoretical Design of Near-Infrared Al3+ Fluorescent Probes Based on Salicylaldehyde Acylhydrazone Schiff Base Derivatives

“…Table summarizes some fluorescent probes for detecting Al 3+ reported in the experimental literature. − All these probes have a salicylaldehyde acylhydrazone Schiff base moiety ( e1 ). Every probe has a very small limit of detection (LOD) for Al 3+ , and each LOD is lower than the WHO standard in drinking water (7.4 μM) .…”