正电性金纳米-核酸适配体纳米生物传感器快速检测野生菌中的α-鹅膏毒肽

Rapid detection of α-amanitin in wild mushroom based on electropositive gold nanoparticles-aptamer nanobiosensor

中文关键词:  适配体  正电性金纳米  α-鹅膏毒肽  快速检测

英文关键词:aptamer  electropositive gold nanoparticles  α-amanitin  wild mushroom

中文摘要:

      目的 构建一种基于正电性金纳米-核酸适配体的纳米生物传感器, 以实现野生菌中α-鹅膏毒肽(α-amanitin, α-AMA)的快速检测。方法 选择可与α-AMA特异性结合的核酸适配体作为识别元件, 以半胱氨酸(cysteamine, Cys)修饰的正电性纳米金(gold nanoparticles, AuNPs)作为信号探针。基于静电吸附作用, 将适配体固载到Cys@AuNPs表面。测定溶液在特定波长处吸光度值的变化, 实现α-AMA的快速检测。结果 该纳米生物传感器检测α-AMA的最佳条件: Cys@AuNPs体积为150 μL, 适配体浓度为6 nmol/L, Cys@AuNPs与适配体反应时间为10 min, α-AMA与适配体结合时间为10 min。在最佳条件下检测α-AMA的线性范围为1~125 ng/mL (r2=0.995)。本体系中α-AMA的检出限为0.87 ng/mL, 加标回收率为98.6%~120.0%。结论 该纳米生物传感器操作简便、灵敏度高、特异性好、成本低廉, 适用于野生菌样品中α-AMA的快速检测。

英文摘要:

      Objective To establish a nanobiosensor based on electropositive gold nanoparticles-aptamer for the rapid detection of α-amanitin (α-AMA) in wild mushroom. Methods The aptamer that specifically binds to α-AMA was selected as the recognition element, and cysteamine (Cys) modified electropositive gold nanoparticles (AuNPs) were used as signal probes. Cys@AuNPs were electrostatically adsorbing the aptamer onto their surfaces. The change in the absorbance value of the solution at a specific wavelength was detected to realize the rapid detection of α-AMA. Results The optimal conditions for the detection of α-AMA by the nanobiosensor were as follows: The volume of Cys@AuNPs was 150 μL, the concentration of aptamer was 6 nmol/L, the reaction time of Cys@AuNPs and aptamer was 10 min, and the binding time of α-AMA and aptamer was 10 min. Under optimum conditions, the α-AMA linear range was 1-125 ng/mL (r2=0.995). The limit of detection of α-AMA in this system was 0.87 ng/mL, and the recovery rates were 98.6%?120.0%. Conclusion This nanobiosensor has the advantages of simple operation, high sensitivity, superior specificity, and low cost. It is suitable for the rapid detection of α-AMA in wild mushroom samples.