Sensitive and rapid sensing of dimetridazole in food and environmental samples using a water-stable luminescent zwitterionic Cd(Ⅱ) metal-organic framework

Abstract

Dimetridazole (DTZ) is such a significant indicator in food safety assessment that a high priority should be given to it. In this work, a novel three-dimensional Metal-Organic Framework zwitterionic composite, {[CdL2]·Cl2·6H2O} (MOF 1), was synthesized by hydrothermal method and applied as a fluorescence probe for the detection of DTZ. Several crucial factors of the obtained MOF 1, such as structure stability, fluorescence properties, selectivity, sensitivity and reproducibility, were studied in detail. A series of sensing investigations demonstrate extremely specific and ultrafast detection of DTZ via a conspicuous fluorescence quenching (Ksv=8.1374 × 104M−1) from MOF 1 under the optimized conditions. The linear range for quantitative detection of DTZ was 0.0 µM∼40.0 µM with a low limit of detection of 0.012 µM. The fluorescence quenching mechanisms have been explained, being caused by a combination of both competitive absorption and photoinduced electron transfer. DTZ in milk, honey, tap and lake water were successfully determined by this fluorescence probe with quick response, and the recovery rates are 97.4%˜102.6%, which indicates MOF 1 having a tremendous application prospect in the detection of DTZ in food and environmental samples.