A Fluorescent Chemosensor Based on Coumarin for Squential Recognition of Al3+ and Pyrophosphate (PPi) in Aqueous Solution

A novel fluorescent chemosensor (E)-N'-(3-((bis(pyridin-2-ylmethyl)amino)methyl)-2-hydroxy-5-methylbenzyl-idene)-7-(diethylamino)-2-oxo-2H-chromene-3-carbohydrazide (1) has been synthesized and showed an obviously off-on-off fluorescence response toward Al3+ and pyrophosphate (PPi) in aqueous solution. The detection limits of sensor 1 were 0.26 mu mol/L to Al3+ and 0.1 mu mol/L to PPi, and the binding stoichiometry was 1 : 1. In addition, the binding mechanism was further confirmed by fluorescence titration, nuclear magnetic titration and ESI-MS. The effective determination pH range for Al3+ and PPi was from 2 to 10, and the cycle response test could reach 4 times.

Automated summary

The novel fluorescent chemosensor 1 showed a significant off-on-off fluorescence response towards Al3+ and pyrophosphate (PPi) in aqueous solution, with detection limits of 0.26 mu mol/L for Al3+ and 0.1 mu mol/L for PPi. The binding stoichiometry was found to be 1:1, and the effective determination pH range for Al3+ and PPi was from 2 to 10, with a cycle response test reaching 4 times.