Sensitive detection of diazinon and bioaccumulation monitoring in crops enabled by cu-sealed metal-organic framework nanosystem with target-responsive aggregation-induced emission

The pervasive application of organophosphorus pesticides (OPs) in agriculture led to a persistent accumulation and causing environmental pollution and safety problems. In response, this study presented a Cu(II)-blocked aggregation-induced emission (AIE)-based metal organic framework (MOF) nanosystem for sensing diazinon. Based on the inhibition capability of diazinon on glutathione peroxidases, the oxidation and consumption of glutathione (GSH) was restricted. Owing to redox reaction between Cu(II) and abundant GSH relived by diazinon, the aggregation-induced emission luminogens (AIEgens) sealed in MOF could be released in aqueous solution and reassembled into emissive aggregates with significantly enhanced signals. The phase transformed-AIE fluorescence recovery provided sensitive diazinon detection method with a detection limit of 0.14 ng mL −1 , which was also reliable in food samples and bioaccumulation monitoring in rice. Thus, this work introduced a highly sensitive AIE-MOF-based fluorescence sensing approach for analyzing diazinon in crops, which was of significant importance for food safety and environmental monitoring.