A novel optical probe for Hg2+ in aqueous media based on mono-thiosemicarbazone Schiff base

A novel mono-thiosemicarbazone Schiff base chemosensor Ml (N'-(4-diphenylamino)benzylidene) hydrazinecarbothiohydrazide) was designed and synthesized as a highly selective and sensitive probe for Hg2+ detecting in aqueous media. A remarkable fluorescence quenching at 487 nm was observed in the presence of He2+, accompanied by the red-shift of the absorption spectrum. This sensing system displays remarkable specificity to He2+ against other possible competing ions. The detection limit and the association constant were 3.11 x 10(-8) M and 7.485 x 10(7)M(-1), respectively. Moreover, the disposable test strip will be a promising candidate for point-of-use monitoring of He2+ in environmental and biological samples with the advantages of cost-effectiveness, portability, and convenience. (C) 2017 Elsevier B.V. All rights reserved.