Objective To establish an electrochemical immunosensor for the determination of human epididymis-specific protein 4(HE4)based on Graphene sheet and Au nanoparticle nanocomposite. Methods Firstly, Graphene sheet and Au nanoparticle nanocomposite was coated onto screen printed electrode(SPE)with an enhanced electrochemical active area and good electronic transfer property. HE4 antibody was adsorbed on the nanocomposite, which aimed at assembling more HE4 antigen. Following the immunoreaction with HE4,a double-antibody sandwich immunoassay was performed on SPE using horseradish peroxidase labeled HE4 antibody. Electrochemical detection was carried out for HE4 level in the presence of hydrogen dioxide(H2O2). Results The immunosensor showed broad linear response to the HE4 level comprised between 0 pmol/L and 400 pmol/L with a limit of detection(LOD) of 0.5 pmol/L. Conclusions The electrochemical immunosensor allows the identification of patients at risk of ovarian cancer,providing a new,fast and simple approach for early diagnosis in daily clinical practice.%目的 建立一种基于石墨烯和纳米金粒子自组装纳米复合物检测卵巢癌患者血清人附睾蛋白4(HE4)的电化学免疫检测新方法.方法 将石墨烯和纳米金粒子复合物组装在丝网印刷电极(SPE)表面,利用纳米金粒子比表面积大和石墨烯电子传导速率快等特点,将大量的HE4一抗吸附在纳米金表面,继而结合大量抗原.根据双抗体夹心法原理,大量的辣根过氧化物酶标记的抗体也与抗原结合,利用辣根过氧化物酶催化过氧化氢(H2O2)产生的电流信号测定HE4水平.结果 新建传感器检测HE4的范围是0~400 pmol/L,检出限(LOD)是0.5 pmol/L.结论 所建方法可用于早期评估受检者患卵巢癌的风险,是临床早期诊断卵巢癌快速、简便的新方法.
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