基于适配体荧光传感器检测山药和薏苡仁中的赭曲霉毒素A

目的 构建一种操作简单、选择性好、快速检测山药和薏苡仁中赭曲霉毒素A(ochratoxinA,OTA)的适配体荧光传感检测方法。方法 制备表面包裹适配体且孔穴负载荧光染料罗丹明6G的二氧化硅纳米颗粒,OTA与其表面的适配体结合后,检测溶液的荧光信号变化,从而实现OTA浓度的检测。结果 在最佳条件下, OTA的质量浓度在5～500 ng/mL范围内与荧光强度差值呈良好的线性关系,相关系数为0.9918,检出限为2.06ng/mL。应用于山药和薏苡仁中OTA的检测,加标回收率为90.7%～107.1%,相对标准偏差为2.41%～5.66%。结论 该方法操作简便、选择性好、稳定性高,有望用于药食同源中药材中OTA的快速检测。

Fluorescence detection of ochratoxin A based on specific aptamer in Rhizoma dioscoreae and Coixseed semen

Objective To develop a fluorescent sensor with simple operation,high selectivity and rapid detection of ochratoxin A(OTA)in Rhizoma dioscoreae and Coixseed semen based on specific aptamer.Methods The silica nanoparticles of the surface wrapped adapter and the hole load fluorescent dye Rhodamin 6 G were prepared,and OTA was combined with its surface adapter,the changes of fluorescence signal in the solution were detected,so as to detect the concentration of OTA.Results Under optimum conditions,OTA had a good linear relationship with the difference of fluorescence intensity in the mass concentration range of 5-500 ng/mL.The correlation coefficient was 0.9918,and the limit of detection was 2.06 ng/mL.This method was applied to the detection of OTA in Rhizoma dioscoreae and Coixseed semen,the recovery rates of OTA addition levels were 90.7%-107.1%,and the relative standard deviation were 2.41%-5.66%.Conclusion This method is simple,selective and stable,it is expected to be used for the rapid detection of OTA in Chinese medicinal materials homologous to medicine and food.