Dual-potential ratiometric electrochemiluminescence (ECL) is in favor of resistance to environmental interference. However, two kinds of emitters or coreactants, and a wide scan potential range (>2 V) are mandatory. This work developed a new dual-potential ratiometric ECL sensor for detection of carcinoembryonic antigen (CEA) using single emitter (luminol) and single coreactant (HO) with a mild potential range from −0.1 to 0.6 V. Luminol could produce a strong cathodic ECL () induced by hydroxyl radicals (HO‧) from the reduction of HO, and a relatively weak anodic ECL (). After the ferrocene modified CEA aptamer (Apt-Fc) was attached, Fc could promote by catalyzing the oxidation of HO, and reduce by consuming HO‧. With the cycling amplification of the exonuclease I, CEA could substantially reduce the amount of Apt-Fc, resulting in the decrease of and the rise of . So, the ratio of to (/) was used as the detection signal, realizing the sensitive determination of CEA from 0.1 pg mL to 10 ng mL with a LOD of 41.85 fg mL (S/N = 3). The developed sensor demonstrated excellent specificity, stability and reproducibility, with satisfactory results in practical detection.

中文翻译：

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基于单发射体和单共反应物的双电位比率电化学发光法灵敏检测癌胚抗原

双电位比率电化学发光（ECL）有利于抵抗环境干扰。然而，两种发射体或共反应物以及宽扫描电势范围（> 2 V）是强制性的。这项工作开发了一种新型双电位比率式ECL传感器，用于使用单发射体（鲁米诺）和单共反应剂（H2O）检测癌胚抗原（CEA），其温和电位范围为-0.1至0.6 V。鲁米诺可以产生强阴极ECL () 由 H2O 还原产生的羟基自由基 (HO·) 诱导，并且阳极 ECL 相对较弱 ()。二茂铁修饰的CEA适配体(Apt-Fc)附着后，Fc可以通过催化H2O的氧化来促进，并通过消耗H2O·来还原。随着核酸外切酶I的循环放大，CEA可以大幅减少Apt-Fc的量，导致 的减少和上升。因此，以与(/)的比值作为检测信号，实现了0.1 pg·mL至10 ng·mL的CEA的灵敏测定，LOD为41.85 fg·mL (S/N = 3)。所开发的传感器表现出优异的特异性、稳定性和重现性，在实际检测中取得了满意的结果。