基于丝网印刷电极和乙酰胆碱酯酶安培生物传感器的黄曲霉毒素检测方

Acetylcholinesterase Amperometric Biosensor Based on Screen-printed Carbon Electrodes for the Detection of Aflatoxin B1

摘要:

为实现黄曲霉毒素B1的快速、实时检测，利用制作成本低、响应速度快、重复性好、样品用量少的丝网印刷电极，和对黄曲霉毒素B1具有抑制作用的乙酰胆碱酯酶，构建检测黄曲霉毒素B1的电化学传感器。利用石墨烯、普鲁士蓝、壳聚糖和纳米金作为丝网印刷电极的修饰材料，采用循环伏安法，优化传感器的反应条件，分别选取反应pH 7.5、负载酶量0.25 U、抑制时间14 min作为该传感器测定黄曲霉毒素B1的最优条件。以乙酰胆碱酯酶作为黄曲霉毒素B1的抑制剂，构建的电化学传感器对黄曲霉毒素B1的线性检测范围为1~64 μg/mL，相关系数为0.9948, 检出限0.05 μg/mL。对花生样品中进行检测，其加标回收率为82.5%~114.1%，具有良好的重现性和稳定性，选择性好。该检出限低于我国花生中黄曲霉毒素的限量标准，可用于花生中的黄曲霉毒素B1的检测。

Abstract:

In order to realize rapid and real-time detection of aflatoxin B1, an electrochemical sensor for detecting aflatoxin B1 was constructed using the screen-printed electrode (which is advantageous in low production cost, fast response, good repeatability and small sample amount), and acetylcholinesterase (which inhibits aflatoxin B1). Using graphene, Prussian blue, chitosan and gold nanoparticles as the modification materials for the screen-printed electrodes, the reaction conditions for the sensor were optimized by cyclic voltammetry. The optimal conditions for the detection of aflatoxin B1 were: pH 7.5, enzyme loading 0.25 U, and inhibition time 14 min. Acetylcholinesterase was used as an inhibitor of the aflatoxin B1, and the obtained biosensor exhibited a linear detection range for aflatoxin B1 from 1 to 64 μg/mL (with a correlation coefficient of 0.9948 and detection limit of 0.05 μg/mL). For the detection of peanut samples, the sensor had a spiked recovery rate in the range of 82.5%~114.1%, with good reproducibility, stability and selectivity. The detection limit was lower than that for the aflatoxins in the peanuts in China, and the developed sensor can be used for the detection of aflatoxin B1 in peanuts.