基于表面增强拉曼光谱适配体传感器检测植物蛋白肉中的黄曲霉毒素B_(1)

Detection of aflatoxin B_(1) in vegetable protein meat based on surface enhanced Raman spectral aptamer sensor

目的研发表面增强拉曼散射(surface enhanced of Raman scattering,SERS)适配体传感器检测植物蛋白肉中的黄曲霉毒素B_(1)(aflatoxin B_(1),AFB_(1))的方法。方法传感器由巯基适配体修饰的金包四氧化三铁磁性纳米粒子作为捕获底物与巯基适配体互补链修饰的金包二氧化硅纳米粒子作为信号探针所组成。通过适配体与AFB_(1)的特异性结合可以导致捕获底物释放信号探针,SERS信号强度随着AFB_(1)的浓度的变化而发生变化,从而实现对AFB_(1)的检测。结果通过实验条件的优化,得到线性回归方程为Y=-222.07lg X+5723.12,r^(2)=0.9986的标准曲线,检出限为0.37 pg/mL。该SERS传感器成功应用于实际样品中AFB_(1)的分析,得到回收率为98.0%~110.0%,相对标准偏差为3.9%~5.7%。结论本研究建立的SERS适配体传感系统可以实现对AFB_(1)的定量检测,可以清楚识别AFB_(1)与其他毒素的SERS信号强度差别,为AFB_(1)的快速检测提供了新的检测方法,在实际样品植物蛋白肉中表现出优异的检测性能。

Objective To develop a method for detecting aflatoxin B_1(AFB_1) in plant protein meat by surface enhanced of Raman scattering(SERS) aptamer sensor.Methods The sensor was composed of magnetic nanoparticles of ferro-tetroxide modified by sulfhydryl aptamer as trapping substrate and gold-coated silica nanoparticles modified by complementary chains of sulfhydryl aptamer as signaling probe.The specific binding of aptamer and AFB_(1) could lead to the capture of substrate release signal probe,and the SERS signal intensity changes with the change of the concentration of AFB_1,so as to realize the detection of AFB_1.Results By optimizing the experimental conditions,the standard curve with linear regression equation Y=-222.07lg X+5723.12,r^(2)=0.9986 was obtained,and the limit of detection was 0.37 pg/mL.The SERS sensor was successfully applied to the analysis of AFB_(1) in actual samples,and the recovery rates were 98.0%-110.0%,and the relative standard deviations were 3.9%-5.7%.Conclusion The SERS aptamer sensing system established in this study can realize the quantitative detection of AFB_(1) and clearly identify the difference in SERS signal strength between AFB_(1) and other toxins,providing a new detection method for the rapid detection of AFB_(1) and showing excellent detection performance in the actual sample plant protein meat.