A facile ratiometric and colorimetric azo-dye possessing chemosensor for Ni2+ and AcO− detection

Abstract

A new tailor-made colorimetric chemosensor 1, containing pyridine and benzothiazole moieties connected through an azo (–N = N–) linkage has been synthesised. In 9:1 (v/v) aqueous THF (pH 7.0 HEPES buffer), it showed a conspicuous naked-eye colour change upon binding to Ni2+ (colourless to light green) and AcO− (colourless to orange) resulting in their ratiometric sensing. The cation and anion recognition property of the chemosensor 1 was monitored by UV–vis spectral analysis and 1H NMR titrations.