A Novel Fluorescent Aptasensor Based on TMU‐16 Metal–Organic Frameworks and Gold Nanoparticles for Ultratrace Detection of Chlorpyrifos in Vegetable Samples

The need for an assay of chlorpyrifos (CPF) that is simple, sensitive, selective, and reliable for CPF detection is widespread in the realm of food safety, given its significant adverse impacts on human health. Recently, aptamer-based biosensors (aptasensors) utilizing fluorescent strategies have emerged as promising candidates. A novel fluorescent aptasensor for ultratrace chlorpyrifos detection in agricultural products was developed using metal-organic frameworks (TMU-16), gold nanoparticles (AuNPs), and a DNA aptamer. The DNA aptamer's conformational change caused the probe's fluorescence to burst at different CPF doses, creating a fluorometric approach for detection. Under optimal experimental conditions, the assay showed high selectivity and sensitivity to CPF within 100-3500 pM, with a low detection limit of 45 pM. The sensing platform successfully detected CPF in cucumber and tomato samples, demonstrating its reliability in detecting CPF in vegetable samples. The proposed fluorescent aptasensor aims to improve CPF detection methods in food safety.