基于胶体金适配体侧向层析试纸快速检测草甘膦

An Aptamer-based Lateral Flow Test Strip for Rapid Detection of Glyphosate

摘要:

该研究以金纳米颗粒标记的适配体作为探针，开发了一种基于适配体的侧流检测条，用于草甘膦（GLY）的快速检测。分析了实验过程中NaCl和适配体的浓度、链霉亲和素和生物素化DNA的摩尔比，以及金纳米颗粒-适配体复合物（AuNPs-Apt）的加载量等对灵敏度的影响。最佳实验条件为：NaCl浓度为80 mmol/L，适配体使用浓度为500 nmol//L，链霉亲和素与Bio-DNAT的摩尔比为1:3，AuNPs-Apt的加载量为30 μL。在最佳实验条件下，视觉分辨质量浓度为20 ng/mL，线性范围为5~200 ng/mL，检出限为5 ng/mL。用于添加GLY的茶叶样品的测定，回收率在95.13%到105.24%之间，相对标准偏差（RSD）为4.73%~8.28%。所有的检测都可以在5 min内完成。结果表明，开发的基于适配体的侧流检测条是一种快速灵敏检测GLY的潜在替代工具。

Abstract:

In this study, an aptamer-based lateral flow test strip was developed for the rapid detection of glyphosate (GLY) using gold nanoparticles labeled aptamers as probes. The effects of experimental conditions, including the concentrations of aptamer and NaCl used, the molar ratio of streptavidin and biotinylated DNA, and the loading quantity of gold nanoparticleaptamer complexes (AuNPs-Apt) on the sensitivity were analyzed. The optimal experimental conditions were as follows: NaCl concentration, 80 mmol/L; aptamer concentration, 500 nmol/L; the molar ratio of streptavidin to Bio-DNAT, 1:3; the loading amount of AuNPs-Apt, 30 μL. Under the optimal experimental conditions, the visual resolution concentration was 20 ng/mL, with a linear range of 5~200 ng/mL and a limit of detection as 5 ng/mL. This aptamer-based strip was applied to the determination of GLY in spiked tea samples, and the recoveries were from 95.13% to 105.24% with relative standards deviation (RSD) of 4.73%~8.28%. All tests could be completed within 5 min. The results showed that the developed aptamerbased lateral flow test strip has the potential to be an alternative tool for the rapid and sensitive detection of GLY.