Aflatoxin B1 (AFB1) is one of the most toxic mycotoxins. In view of the great harm of AFB1, it has attracted much attention to explore a super-sensitive and low-cost rapid detection method for aflatoxin B1. Herein, a dual-readout colorimetric immunoassay was established for the detection of AFB1. Under the catalysis of alkaline phosphatase (ALP), phenyl phosphate (PP) can produce phenol by dephosphorylation. Then phenol can react with 2,6-dibromoquinone-4-chloroimide (DBQC) under alkaline conditions to produce blue halogenated indophenol (HIP). Through this reaction, the color of the solution became blue, which can be observed by the naked eye. In addition, this color signal can be converted into digital signal via smartphone, enabling quantitative detection of AFB1. Under the optimal condition, the detection limit of this colorimetric immunoassay was 0.70 ng/mL by naked eye and 0.013 ng/mL by smartphone. The application results showed that the proposed daul-readout colorimetric immunoassay was feasible and real-time for AFB1 detection in actual samples.

黄曲霉毒素 B1 (AFB1) 是毒性最强的霉菌毒素之一。鉴于AFB1的巨大危害，探索超灵敏、低成本的黄曲霉毒素B1快速检测方法备受关注。在此，建立了双读数比色免疫分析法来检测 AFB1。在碱性磷酸酶（ALP）的催化下，磷酸苯酯（PP）脱磷酸生成苯酚。然后苯酚在碱性条件下与2,6-二溴醌-4-氯酰亚胺(DBQC)反应生成蓝色卤化靛酚(HIP)。通过该反应，溶液的颜色变成蓝色，可以用肉眼观察到。此外，这种颜色信号可以通过智能手机转换为数字信号，从而实现AFB1的定量检测。在最佳条件下，该比色免疫分析的肉眼检测限为0.70 ng/mL，智能手机检测限为0.013 ng/mL。应用结果表明，所提出的双读出比色免疫分析法对于实际样品中AFB1的检测是可行的、实时的。