School of Chemistry and Chemical Engineering, Yangzhou University, Yangzhou, Jiangsu, 225002, PR China.
School of Chemistry and Chemical Engineering, Yangzhou University, Yangzhou, Jiangsu, 225002, PR China.
Biosens Bioelectron. 2021 Aug 1;185:113251. doi: 10.1016/j.bios.2021.113251. Epub 2021 Apr 17.
A novel photoelectrochemical immunosensor was constructed to monitor carcinoembryonic antigen (CEA) based on hybridization chain reaction (HCR)-mediated in situ generation of copper nanoparticles (Cu NPs) and subsequent Cu-dependent quenching reaction, in which titanium dioxide nanoparticles-sensitized double-shell zinc cadmium sulfide hollow nanospheres (TiO/DS-ZnCdS)-modified ITO electrode and anti-CEA antibody-modified 96-well plate served as biological recognition and signal detection platforms, respectively. The synergistic effect of TiO NPs and DS-ZnCdS hollow nanospheres contributed to the improvement of photoelectric conversion efficiency, and HCR-mediated signal cascade benefited the enhancement of detection sensitivity. In the presence of CEA, biotin-labelled anti-CEA antibodies were immobilized onto anti-CEA antibody-modified 96-well plate, and triggered HCR process to form long double stranded DNA, which could adsorb a large number of Cu ions and then in situ form Cu NPs on double stranded DNA template by a facile reduction reaction. After acid treatment, the dissolved Cu ions could significantly reduce the photocurrent response due to the generation of CuS. Under optimal conditions, the immunosensor exhibited a desirable liner range of 1 pg mL - 50 ng mL and a low detection limit of 0.1 pg mL, as well as excellent selectivity and stability. Meanwhile, the recoveries of human serum sample analysis ranged from 96.8% to 103.6%, and the relative standard deviation was less than 7.40%, showing a good feasibility in early clinical diagnosis.
一种基于杂交链式反应（HCR）介导的原位生成铜纳米粒子（Cu NPs）和随后的 Cu 依赖性猝灭反应的光电化学免疫传感器被构建，用于监测癌胚抗原（CEA）。在该传感器中，二氧化钛纳米粒子敏化的双壳层锌镉硫化镉空心纳米球（TiO/DS-ZnCdS）修饰的 ITO 电极和抗 CEA 抗体修饰的 96 孔板分别作为生物识别和信号检测平台。TiO NPs 和 DS-ZnCdS 空心纳米球的协同作用有助于提高光电转换效率，而 HCR 介导的信号级联反应则有利于提高检测灵敏度。在 CEA 存在的情况下，生物素标记的抗 CEA 抗体被固定在抗 CEA 抗体修饰的 96 孔板上，并触发 HCR 过程形成长双链 DNA，双链 DNA 模板可以通过简单的还原反应吸附大量的 Cu 离子，并原位形成 Cu NPs。经过酸处理后，由于 CuS 的生成，溶解的 Cu 离子会显著降低光电流响应。在最佳条件下，该免疫传感器表现出理想的线性范围为 1 pg mL - 50 ng mL - 1，检测限低至 0.1 pg mL - 1，具有良好的选择性和稳定性。同时，人血清样品分析的回收率范围为 96.8%至 103.6%，相对标准偏差小于 7.40%，在早期临床诊断中具有良好的可行性。
