Highly sensitive fluorescent aptasensor based on magnetic metal-organic framework for aflatoxin B1 detection.

Aflatoxin B1 (AFB1) has strong carcinogenicity, mutagenicity, and teratogenicity even at low concentrations, presenting a major risk to food safety and human health, hence, it is crucial to develop a sensitive detection technique for AFB1. Consequently, cadmium telluride (CdTe) quantum dots conjugated with AFB1 aptamers serve as fluorescent signal probes, whereas FeO@UiO-66-NH nanocomplexes are employed as magnetic carriers and fluorescence quenchers. FeO@UiO-66-NH reduces background signal interference, thereby enhancing detection sensitivity and Förster Resonance Energy Transfer (FRET) efficiency. We have developed a highly sensitive and selective magnetron fluorescence aptasensor based on FRET for the specific detection of AFB1. Under the ideal experimental conditions, the linear range of AFB1 is 0.001-200 ng/mL, with a linear equation of y = 0.16x+0.65 (R = 0.996), and the detection limit is 0.012 ng/mL. The aptasensor demonstrated superior selectivity, reproducibility, and stability for AFB1, the recoveries for real samples of corn and wheat ranged from 95 % to 103 %, demonstrating the feasibility and practicality of the sensor. Furthermore, the accuracy of the aptasensor was verified by comparison with the results of high performance liquid chromatography, indicating that the aptasensor holds significant potential for practical detection applications.