摘要
建立了一种新的纳米金增强伏安免疫分析方法.以人免疫球蛋白G(HIgG)为模型,羊抗人免疫球蛋白G(GAH IgG)固定于电极表面构成免疫传感器界面.固定化抗体与分析目标物HIgG发生免疫反应而将HIgG捕获,再通过夹心法将纳米金标记的GAH IgG结合于电极界面.通过金增强过程可在纳米金上进一步沉积金形成直径较大的纳米金颗粒,使电极表观面积大大增加,进而显著改善电极表面的电极表面吸附电化学行为,故用循环伏安法或差示脉冲法测定的金增强前后吸附伏安电流变化值可实现界面结合的金纳米探针的含量,从而间接实现分析目标物HIgG的测定.其线性范围为50 ng/mL^1μg/mL,检测限为20 ng/mL.实验表明该法灵敏度高,选择性好,实现简便,可望成为一种新型有潜力的高灵敏免疫传感技术.
The present study has developed a novel voltammetric immunosensing method based on colloidal gold enhancement.This method demonstrates the implementation of a sandwich immunoassay of a model analyte,Human immunoglobulin G（HIgG）,using the colloidal gold-labeled goat anti-human immunoglobulin G（GAH IgG） as the detection probe.The electroless catalytic deposition of gold ions on the gold nanoparticles enables the growth of the gold nanoparticles at the electrode surface,facilitating the electron transfer between the electroactive probes in the solution and the electrode surface.Therefore,one obtains a substantial amplification of the adsorptive electrochemical signal that shows linear dependency upon the analyte concentration.The linear range of this method spans the concentration of HIgG from 50ng～1μg/mL and has a detection limit of 20ng/mL at a signal-to-noise ratio of 3.The developed method is expected to hold great promise in immunosensing due to the ease of implementation,high sensitivity and specificity.
出处
《德州学院学报》
2011年第4期47-51,共5页
Journal of Dezhou University
关键词
胶体金
免疫
纳米颗粒标记
金增强
差示脉冲法
gold nanoparticle
immunoassay
nanopartical labeling
gold enhancement
differential pulse voltammetry
