An acetate sensor based on azo in aqueous media

A colorimetric sensor 1,N,N′-di-(2-hydroxy-5-(phenldiazenyl)benzaldehyde)-1,3-diiminothiourea for acetate in DMSO and 9/1 DMSO/H2O (v/v) mixtures was designed and synthesized. The binding ability evaluated by UV–vis experiment reveals that sensor 1 can selectively recognize acetate. In addition, the color changes induced by anions can provide a way of detection by ‘naked-eye’. The further insights to the nature of interactions between the sensor 1 and AcO− were investigated by 1H NMR titration experiments in 9/1 DMSO-d6/H2O (v/v).