A small-molecule and resumable two-photon fluorescent probe for Zn2+ based on a coumarin Schiff-base

In this study, a simple one-photon and two-photon probe, 7-(4'-(diethylamino)-2'hydroxybenzylideneimino)-4-methyl coumarin, for Zn2+ is designed and synthesized. The sensor shows high selectivity towards Zn2+ ions with significant fluorescence intensity enhanced at 500 nm, which might be attributed to the formation of 2:1 stoichiometric L-Zn complex resulting in the restricted C=N isomerization and the inhibited photo-induced electron transfer. More importantly, the reversibility of the recognition process of HL is performed by adding a Zn2+ bonding agent Na(2)EDTA. (C) 2016 Elsevier B.V. All rights reserved.