LAUSR

An integrated aflatoxin B1 (AFB1) detection platform with quantum dot (QD)-based electrochemical immunosensor and an automated magneto-controlled pretreatment system was successfully developed. The automated pretreatment system adopts the immunoaffinity magnetic beads (IMB) as the capture probe of AFB1 and QD-labeled AFB1 complete antigen (AFB1-BSA-QDs) as the signal probe. AFB1-BSA-QDs can be easily converted into corresponding metallic cations through acidic treatment, which can be detected electrochemically via anode stripping voltammetry (ASV). Moreover, a disposable screen-printed electrode (SPE) without requiring any further modification is used in the novel electrochemical immunosensor‚ making routine testing feasible. Under optimal conditions, the detectable concentration range of AFB1 was 0.08–800 μg/kg. The metal ion signal associated linearly with the logarithm of AFB1 concentration within the range of 5–240 μg/kg, with a detection limit of 0.05 μg/kg. The spiked recoveries of three different concentrations in four different matrixes ranged from 83.9 to 118.0%, and inter-day relative standard deviations were below 10%. Furthermore, the methodology was validated by analyzing naturally contaminated samples, and results of the novel immunosensor were in good agreement with those of LC-MS/MS, demonstrating the potentiality of the developed method for the monitor of AFB1 in cereals and oils.