Highly Sensitive Ratiometric Chemosensor for Selective 'Naked-Eye' Nanomolar Detection of Co~(2+) in Semi-Aqueous Media

摘要

An easy-to-prepare chemosensor, (E)-1-(phthalazine-4-yl)-2-(1- (pyridine-2-yl)ethylidene) hydrazine (3), structurally characterized by single X-ray crystallography, is developed for the selective and sensitive detection of Co~(2+) in aqueous media. Chemosensor 3 shows both absorption and fluorescence responses to Co~(2+) by forming a 1:1 complex (among the surveyed metal ions) with a detection limit down to 50 nm. It can also be used as a 'naked-eye' sensor due to the outstanding visible and emission color changes from yellow to red and blue to orange, respectively.