The sensitivity of electrochemical (EC) sensors has been improved through the development of multiple approaches. However, the majority of EC sensors were limited in their practical application by high costs or tedious procedures. Herein, based on ethylenediaminetetraacetic acid (EDTA)-Pb complexation reaction, a facile and affordable immunosensor was designed. Pb-magnesium silicate hydrate was served as the sensing substrate. The immunorecognition process was carried out in the Eppendorf tube, and antibody-functionalized Pb-polydopamine was utilized as immunoprobe. In the tube, the quantitative and appropriate excess of EDTA was introduced to complex with Pb on the immunoprobes. The remaining EDTA was added to the sensing substrate surface to coordinate with some Pb in it. This leaded to the reduction of the EC signal of Pb, which was related to the antigen concentration. Using prostate-specific antigen as the model analyte, the sensitive detection was realized with a low limit of detection (30.49 fg mL). Remarkably, the assay results were available within 24 min, sensibly faster than the most existing EC sensors.

中文翻译：

---

一种基于 EDTA-Pb2+ 络合反应的简便电化学免疫传感器

通过多种方法的开发，电化学（EC）传感器的灵敏度得到了提高。然而，大多数EC传感器由于成本高或程序繁琐而限制了其实际应用。在此，基于乙二胺四乙酸（EDTA）-Pb络合反应，设计了一种简便且经济的免疫传感器。水合硅酸铅镁用作传感基质。免疫识别过程在Eppendorf管中进行，并使用抗体功能化的Pb-聚多巴胺作为免疫探针。在试管中，引入定量且适当过量的 EDTA，与免疫探针上的 Pb 形成复合物。将剩余的 EDTA 添加到传感基板表面以与其中的一些 Pb 配位。这导致Pb的EC信号减弱，这与抗原浓度有关。使用前列腺特异性抗原作为模型分析物，实现了低检测限（30.49 fg mL）的灵敏检测。值得注意的是，检测结果可在 24 分钟内获得，明显比大多数现有 EC 传感器更快。