A simple and convenient electrochemiluminescence immunoassay (ECLIA) has been developed by using gold nanoparticles (AuNPs) as both label and co-reactant. In this novel ECLIA, the detection antibodies labeled with AuNPs as co-reactant reacts directly with ruthenium complex to produce electrochemiluminescence (ECL), which avoids the weakness of luminophore as a label. The feasibility of the new method was investigated through the sandwich ECL immunosensor for the determination of human immunoglobulin (HIgG), and excitation of luminescence was respectively driven by linear sweep voltammetry and step potential. Under the optimal conditions, ECL intensity of the immunosensor increased with HIgG concentration in a wide range from 0.01 to 10.0 ng/mL and displayed linear response to logarithm of HIgG concentration. The results showed that the detection limit was 5 pg/mL, and the relative error was no more than 4.6% for the repeated measurements. The relative standard deviation was less than 2.9% for the determination of the standard sample, which can meet the requirement of ECLIA.

通过使用金纳米颗粒（AuNPs）作为标记物和共反应物，开发了一种简单便捷的电化学发光免疫测定法（ECLIA）。在这种新型ECLIA中，以AuNPs作为共反应物标记的检测抗体直接与钌配合物发生反应，产生电化学发光（ECL），避免了发光体作为标记的弱点。通过夹心ECL免疫传感器测定人免疫球蛋白（HIgG），研究了该新方法的可行性，线性扫描伏安法和步进电位法分别驱动发光激发。在最佳条件下，免疫传感器的ECL强度随HIgG浓度在0.01到10.0 ng / mL的较宽范围内增加，并显示对HIgG浓度对数的线性响应。结果表明，检出限为5 pg / mL，重复测量的相对误差不超过4.6％。测定标准样品的相对标准偏差小于2.9％，可以满足ECLIA的要求。