Highly selective detection of isatin using curcumin analogue and its application in real samples

Abstract

A novel curcumin analogue bearing indole NH (DP4) unit was synthesized as fluorescent sensor for isatin in biological system with fairly selective over other competitors. The sensor triggered a “turn-off” fluorescence response toward isatin with concurrent decrease with fluorescence intensity in PBS buffer solution at pH 7.4. The detection limit of isatin was calculated as low as 241 nM. It can be employed to detect isatin in biological samples in buffer medium. The hydrogen bonding interaction of probe with isatin was studied using 1H NMR titration and DFT calculation.