3-Aminophenylboronic acid-functionalized molybdenum disulfide quantum dots for fluorescent determination of...

A simple method is reported for hypochlorite determination based on fluorescence 3-aminophenylboronic acid-functionalized molybdenum disulfide quantum dots (B-MoS₂ QDs). B-MoS₂ QDs with strong fluorescence at 380 nm have been successfully synthesized by the amidation reaction between APBA and hydrothermal MoS₂ QDs. Hypochlorite sensing was proposed utilizing the fluorescent quenching effect of 3,3',5,5'-tetramethylbenzidine dihydrochloride (TMB) on B-MoS₂ QDs and the fast redox reaction between hypochlorite and TMB. The fluorescent quenching effect of TMB to B-MoS₂ QDs was proved to be caused by static dynamic quenching and inner filter effect. A good linear relationship was obtained in the hypochlorite concentration range from 1 to 20 μM, and the limit of detection (LOD) was 36.8 nM. The proposed fluorescent detection assay was simple and fast, taking only 5 min at room temperature. Satisfactory results were obtained in the standard spike recovery tests on tap water and milk samples, which indicate high potential in constructing fluorescent bio-detection assays.