Ai Zhujun, Zhao Min, Han Daobin, Chen Ke, Xiong Dongmei, Tang Hua
Key Laboratory of Molecular Biology for Infectious Diseases (Ministry of Education), Institute for Viral Hepatitis, Department of Infectious Diseases, The Second Affiliated Hospital, Chongqing Medical University, Chongqing, 400016, China.
Key Laboratory of Clinical Laboratory Diagnostics (Ministry of Education), College of Laboratory Medicine, Chongqing Medical University, Chongqing, 400016, China.
Biosens Bioelectron. 2021 May 1;179:113059. doi: 10.1016/j.bios.2021.113059. Epub 2021 Feb 1.
Herein, we report a novel dual-quenching electrochemiluminescence (ECL) immunosensor for detecting protein induced by vitamin K absence or antagonist-II (PIVKA-II) based on ECL resonance energy transfer (ECL-RET). In this protocol, self-accelerated ECL hybrids of CeO and Au nanoparticles functionalized g-CN nanosheets (CeO-Au-g-CN) were prepared, which exhibited high ECL emission in the presence of SO as a coreactant for "signal on" state. Concretely, CeO with a reproducible redox couple of Ce and Ce could act as an efficient co-reaction accelerator to generate more oxidizing intermediate (SO) to significantly self-promote the ECL emission of g-CN NSs/SO ECL system. Besides, Au nanoparticles not only accelerated electron transfer in the ECL process, but also provided massive active sites for biomolecules immobilization. The dual quenching labels of Ag nanocubes modified with vitamin B (AgNCs-VB) were firstly proposed towards g-CN NSs/SO ECL system by ECL-RET, resulting in the remarkable ECL decrease for "signal off" state. Based on the sandwich immunoreaction, the "on-off" PIVKA-II ECL immunosensor gratifyingly possessed excellent detection sensitivity with the linear range of 0.4 pg mL-10 ng mL and the low detection limit of 28.46 fg mL (S/N = 3). This presented strategy might provide a potential alternative tool for PIVKA-II detection in medical research and early clinical diagnostics of hepatocellular carcinoma.
在此，我们报道了一种基于电化学发光共振能量转移（ECL-RET）的新型双猝灭电化学发光（ECL）免疫传感器，用于检测维生素K缺乏或拮抗剂-II诱导蛋白（PIVKA-II）。在该方案中，制备了二氧化铈和金纳米粒子功能化的g-C3N4纳米片的自加速ECL杂化物（CeO2-Au-g-C3N4），其在作为共反应剂的S2O82-存在下表现出高ECL发射，处于“信号开启”状态。具体而言，具有可重复的Ce4+/Ce3+氧化还原对的CeO2可以作为有效的共反应促进剂，生成更多的氧化中间体（S2O82-），以显著自我促进g-C3N4纳米片/S2O82- ECL体系的ECL发射。此外，金纳米粒子不仅加速了ECL过程中的电子转移，还为生物分子固定提供了大量活性位点。首次通过ECL-RET提出了用维生素B修饰的银纳米立方体（AgNCs-VB）对g-C3N4纳米片/S2O82- ECL体系的双猝灭标记，导致“信号关闭”状态下ECL显著降低。基于夹心免疫反应，“开-关”型PIVKA-II ECL免疫传感器令人满意地具有出色的检测灵敏度，线性范围为0.4 pg mL-1至10 ng mL-1，检测下限低至28.46 fg mL-1（S/N = 3）。该提出的策略可能为医学研究中PIVKA-II的检测以及肝细胞癌的早期临床诊断提供一种潜在的替代工具。
