Zhu Xiaodi, Shan Jingkai, Dai Li, Shi Feifei, Wang Jinshen, Wang Huan, Li Yuyang, Wu Dan, Ma Hongmin, Wei Qin, Ju Huangxian
Collaborative Innovation Center for Green Chemical Manufacturing and Accurate Detection; Key Laboratory of Interfacial Reaction & Sensing Analysis in Universities of Shandong, School of Chemistry and Chemical Engineering, University of Jinan, Jinan, 250022, Shandong. China.
Department of Rehabilitation, Shandong Provincial Hospital Affiliated to Shandong First Medical University, Jinan, 250021, Shandong, China.
Talanta. 2023 Mar 1;254:124134. doi: 10.1016/j.talanta.2022.124134. Epub 2022 Nov 23.
Photoelectrochemical (PEC) immunoassays exhibiting high sensitivity and decent operability have considerable potential in areas such as cancer diagnostics. In particular, cathodic PEC configurations can prevent interference from reductive substances, which can occur in biological samples; however, challenges remain in terms of sensitivity and operability. In this study, separate-type PEC immunoassays were developed for carcinoembryonic antigen (CEA) by combining microplate-based immune recognition and off-on cathodic PEC detection. Polydopamine (PDA)-coated Prussian blue (PB) nanoparticles (PB@PDA NPs) were used as signal tags to label the detection antibody. The PB NPs and PDA captured on the microplates both disassembled under strongly alkaline conditions to generate redox-active electron acceptors. The disassembled products were quantitatively transferred to PEC detection cells and synergistically enhanced the PEC current with microstructured BiOI, which operated as a cathodic semiconductor electrode. As proof of principle, carcinoembryonic antigen (CEA) was applied to elucidate the potential application of PEC immunoassay in clinical diagnosis, and the obtained linear range of the sensor was 0.001-100 ng mL with the detection limit of 54.9 fg mL (S/N = 3). The proposed separate-type off-on PEC strategy showed high sensitivity and decent operability for CEA detection, indicating its potential for the identification of other tumor markers.
具有高灵敏度和良好可操作性的光电化学（PEC）免疫分析在癌症诊断等领域具有巨大潜力。特别是，阴极PEC配置可以防止生物样品中可能出现的还原物质的干扰；然而，在灵敏度和可操作性方面仍然存在挑战。在本研究中，通过结合基于微孔板的免疫识别和开-关阴极PEC检测，开发了用于癌胚抗原（CEA）的分离型PEC免疫分析方法。用聚多巴胺（PDA）包覆的普鲁士蓝（PB）纳米颗粒（PB@PDA NPs）作为信号标签来标记检测抗体。在微孔板上捕获的PB NPs和PDA在强碱性条件下均会分解，以产生具有氧化还原活性的电子受体。分解产物被定量转移到PEC检测池中，并与作为阴极半导体电极的微结构BiOI协同增强PEC电流。作为原理验证，应用癌胚抗原（CEA）来阐明PEC免疫分析在临床诊断中的潜在应用，所获得的传感器线性范围为0.001-100 ng mL，检测限为54.9 fg mL（S/N = 3）。所提出的分离型开-关PEC策略对CEA检测显示出高灵敏度和良好的可操作性，表明其在识别其他肿瘤标志物方面的潜力。
