为解决黄曲霉毒素B1（aflatoxin B1，AFB1）快速检测方法中信号标记物稳定性差的问题，建立基于金属有机骨架的酶联免疫法检测米粉中AFB1。该研究采用仿生矿化方法将辣根过氧化物酶（horse radish peroxidase，HRP）封装在沸石咪唑骨架结构材料（zeolite imidazole frameworks-8，ZIF-8）中作为信号标记物。发现HRP@ZIF-8复合材料在碱性条件、高温等极端条件下能保持稳定的催化活性。在此基础上建立间接竞争免疫比色法检测AFB1，通过肉眼可直接分辨含有AFB1样品。在最佳条件下，随着AFB1浓度的增加，吸光度在0.01~20 ng/mL内递减，具有明显的线性关系y=0.03×C[AFB1]+0.79，R2=0.99，检测限为72 pg/mL，同时精密度和特异性都达到可接受的水平，AFB1在米粉和面粉中的添加回收率分别在96.00%~105.00%、82.00%~110.00%之间，相对标准偏差均小于5%。该法操作简单、快速、灵敏、特异性好，可用于米粉、面粉等谷类食品中AFB1的痕量检测。

In order to solve the problem of poor stability of signal markers in the rapid detection method of aflatoxin B1 (AFB1), an enzyme-linked immunoassay based on metal organic frameworks (MOFs) was established to detect AFB1 in rice flour. In this study, a biomimetic mineralization method was used to encapsulate horseradish peroxidase (HRP) in the zeolite imidazole framework structure material-8 (ZIF-8) as a signal marker. HRP@ZIF-8 composites could maintain stable catalytic activity under extreme conditions such as alkaline condition and high temperature. On this basis, an indirect competitive immunocolorimetry was established to detect AFB1. The samples containing AFB1 can be directly identified by naked eyes. Under the optimum conditions, the absorbance decreased in the range of 0.01~20 ng/mL with the increase of AFB1 concentration, showing an obvious linear relationship with y =0.03×C[AFB1]+0.78, R2=0.99. The limit of detection was 72 pg/mL, and the precision and specificity were both acceptable. The recoveries of AFB1 in rice flour and flour were 96.00~105.00% and 82.00~110.00%, respectively, with relative standard deviations less than 5%. The method is simple, rapid, sensitive and specific. It can be used for trace determination of AFB1 in cereals such as rice flour and flour.

大宗粮油精深加工教育部重点实验室（武汉轻工大学）开放基金项目（2019GYBQGDKFA01；2020JYBQGDKFB10）