Key Laboratory for Analytical Science of Food Safety and Biology (MOE & Fujian Province), Fujian Provincial Key Laboratory of Electrochemical Energy Storage Materials, State Key Laboratory of Photocatalysis on Energy and Environment, Department of Chemistry, Fuzhou University, Fuzhou 350108, P.R. China.
Analyst. 2021 Jul 21;146(14):4487-4494. doi: 10.1039/d1an00822f. Epub 2021 Jun 28.
Prostate-specific antigen (PSA), a glycoprotein that is most likely to cause prostate cancer, has attracted widespread attention in recent years due to its increasing threat to people's lives and health. Herein, we developed a new signal-amplified photoelectrochemical (PEC) immunosensing method for quantitative monitoring of the target PSA based on the ion-exchange reaction for the in situ formation of ZnO/CdS/AgS nanohybrids triggered by the as-released silver ions (Ag) from silver nanolabels. Initially, the introduction of a target PSA caused the formation of a sandwich immunocomplex in an anti-PSA capture antibody (cAb)-coated microplate with the help of a silver nanoparticle-labeled detection antibody (AgNPs-dAb). Thereafter, the introduced AgNPs were dissolved with acid to release numerous silver ions. In this regard, an ion-exchange reaction occurred between the silver ions and ZnO/CdS nanorods on the photosensitive electrode, thus producing ZnO/CdS/AgS nanohybrids to generate a relatively strong photocurrent. Under optimal conditions, the ion-exchange reaction-based PEC immunoassay exhibited a good linear range of 0.05-50 ng mL and allowed the detection of the target PSA at a concentration as low as 0.018 ng mL. In addition, the PEC immunoassay displayed satisfactory repeatability, high specificity, and acceptable method accuracy. Importantly, the ion-exchange reaction-based PEC immunoassay provides a new perspective for the detection of other disease-related biomarkers by controlling the corresponding antibodies.
前列腺特异性抗原（PSA）是一种糖蛋白，近年来由于其对人们生命和健康的威胁越来越大，引起了广泛关注。在此，我们开发了一种新的基于信号放大的光电化学（PEC）免疫传感方法，用于基于从银纳米标记物中释放出的银离子（Ag）触发的原位形成 ZnO/CdS/AgS 纳米杂化物，定量监测靶标 PSA。最初，在抗 PSA 捕获抗体（cAb）包被的微孔板中，目标 PSA 的引入会在银纳米颗粒标记的检测抗体（AgNPs-dAb）的帮助下形成三明治免疫复合物。此后，用酸溶解引入的 AgNPs 以释放大量银离子。在这方面，银离子与光敏电极上的 ZnO/CdS 纳米棒之间发生离子交换反应，从而产生 ZnO/CdS/AgS 纳米杂化物以产生相对较强的光电流。在最佳条件下，基于离子交换反应的 PEC 免疫分析表现出良好的线性范围为 0.05-50ngmL，允许以低至 0.018ngmL 的浓度检测靶标 PSA。此外，PEC 免疫分析显示出令人满意的重复性、高特异性和可接受的方法准确性。重要的是，基于离子交换反应的 PEC 免疫分析通过控制相应的抗体，为检测其他与疾病相关的生物标志物提供了新的视角。
