Development and Validation of an Automated Magneto-Controlled Pretreatment for Chromatography-Free Detection of Aflatoxin B1 in Cereals and Oils through Atomic Absorption Spectroscopy

A chromatography-free detection of aflatoxin B-1 (AFB(1)) in cereals and oils through atomic absorption spectroscopy (AAS) has been developed using quantum dots and immunomagnetic beads. A magneto-controlled pretreatment platform for automatic purification, labeling, and digestion was constructed, and AFB(1) detection through AAS was enabled. Under optimal conditions, this immunoassay exhibited high sensitivity for AFB(1) detection, with limits of detection as low as 0.04 mu g/kg and a linear dynamic range of 2.5-240 mu g/kg. The recoveries for four different food matrices ranged from 92.6% to 108.7%, with intra- and inter-day standard deviations of 0.7-6.3% and 0.6-6.9%, respectively. The method was successfully applied to the detection of AFB(1) in husked rice, maize, and polished rice samples, and the detection results were not significantly different from those of liquid chromatography-tandem mass spectrometry. The proposed method realized the detection of mycotoxins through AAS for the first time. It provides a new route for AFB(1) detection, expands the application scope of AAS, and provides a reference for the simultaneous determination of multiple poisonous compounds (such as mycotoxins and heavy metals).

Automated summary

A chromatography-free method for the detection of AFB(1) in cereals and oils using quantum dots and immunomagnetic beads coupled with AAS has been developed. This method exhibited high sensitivity, low detection limits, and a wide linear dynamic range. The recoveries for different food matrices were high with low standard deviations. The method was successfully applied to various food samples and showed comparable results to liquid chromatography-tandem mass spectrometry. This method provides a new route for the detection of mycotoxins through AAS and expands the application scope of AAS, making it useful for simultaneous determination of multiple poisonous compounds.