A novel strategy based on nanoprobes for signal amplification was introduced in an electrochemical immunoassay platform. The nanoprobes based on poly(2-hydroxyethyl methacrylate)-r-poly(acrylic acid) (PHEMA-r-PAA) and graphene oxide (GO) have the effect of double signal amplification. The resulting sandwich-type electrochemical immunosensor was able to detect the tumor marker alpha fetal protein (AFP) with high sensitivity and high selectivity. A good linear relationship could be observed in the AFP concentration range of 3.5 pg mL⁻¹ to 35 ng mL⁻¹ (R² = 0.9898), and the minimum detection limit was 0.106 pg mL⁻¹. In addition, the electrochemical immunosensor exhibited good stability and could be applied to AFP detection in clinical serum.

中文翻译：

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基于GO复合纳米探针的电化学免疫传感器检测肿瘤标志物以进行信号放大†

在电化学免疫测定平台中引入了一种基于纳米探针的信号放大新策略。基于聚（2-羟乙基甲基丙烯酸酯）的纳米探针- - [R -聚（丙烯酸）（PHEMA- ř -PAA）和氧化石墨烯（GO）具有双重信号放大的作用。所得的夹心型电化学免疫传感器能够以高灵敏度和高选择性检测肿瘤标志物α胎儿蛋白（AFP）。在AFP浓度范围为3.5 pg mL ^-1至35 ng mL ^-1（R ² = 0.9898）时，可以观察到良好的线性关系，最小检出限为0.106 pg mL ^-1。此外，电化学免疫传感器具有良好的稳定性，可用于临床血清中AFP的检测。