Abstract We report a sandwich-type electrochemical immunoassay for simultaneous determination of carcinoembryonic antigen (CEA) and alpha-fetoprotein (AFP), using multifunctionalized gold nanoparticles as signal tags. Two nanotags including thionine-Au nanoparticles and ferrocene-Au nanoparticles were synthesized and used as distinguishable indicators. The sensor was fabricated by means of co-immobilization of primary anti-CEA (AbCEA) and anti-AFP (AbAFP) antibodies on the surface of Fe3O4 nanoparticle, the strategy is based on observation distinct voltammetric peak derived from distinguish probe (AbCEA-Au-thionine and AbAFP-Au-ferrocene nanotags). Experimental results revealed that this immunosensor enabled simultaneous determination of CEA and AFP in the linear ranges of (0.05–120 ng mL− 1) and (0.05–100 ng mL− 1), respectively. The detection limits (DL) for AFP and CEA were 0.012 ng mL− 1 and 0.018 ng mL− 1, respectively (S/N = 3). Furthermore, the methodology was also evaluated for the analysis of AFP and CEA in the clinical human serum specimens, the obtained results was in desirable agreement with clinical data.

中文翻译：

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使用多功能金纳米标签同时电化学检测癌胚抗原和甲胎蛋白的磁免疫传感器

摘要 我们报告了一种夹心型电化学免疫测定法，使用多功能化金纳米粒子作为信号标签，用于同时测定癌胚抗原 (CEA) 和甲胎蛋白 (AFP)。合成了两种纳米标签，包括硫氨酸-金纳米颗粒和二茂铁-金纳米颗粒，并用作可区分的指示剂。该传感器是通过将初级抗 CEA (AbCEA) 和抗 AFP (AbAFP) 抗体共同固定在 Fe3O4 纳米颗粒表面上制造的，该策略基于观察来自区分探针 (AbCEA-Au) 的明显伏安峰-硫氨酸和 AbAFP-Au-二茂铁纳米标签）。实验结果表明，该免疫传感器能够同时测定线性范围内的 CEA 和 AFP，分别为（0.05-120 ng mL-1）和（0.05-100 ng mL-1）。AFP 和 CEA 的检测限 (DL) 分别为 0.012 ng mL-1 和 0.018 ng mL-1 (S/N = 3)。此外，还评估了该方法用于分析临床人血清标本中的 AFP 和 CEA，获得的结果与临床数据一致。