Wu Yilun, Su He, Yang Junfeng, Wang Zengyuan, Li Daguang, Sun Hang, Guo Xingyuan, Yin Shengyan
State Key Laboratory on Integrated Optoelectronics, College of Electronic Science and Engineering, Jilin University, Changchun, Jilin 130012, China.
Key Laboratory of Bionic Engineering (Ministry of Education), College of Biological and Agricultural Engineering, Jilin University, Changchun, Jilin 130022, PR China.
J Colloid Interface Sci. 2020 Nov 15;580:583-591. doi: 10.1016/j.jcis.2020.07.064. Epub 2020 Jul 16.
Alpha-fetoprotein (AFP) in adult serum often appears in early liver cancer. Therefore, early detection of an abnormal elevation of AFP concentration is important for the early diagnosis and treatment of primary liver cancer. In this work, a photoelectrochemical (PEC) electrode was fabricated for AFP-sensitive detection based on a reduced graphene oxide (rGO) honeycomb structure. After layer-by-layer bioconjugation, the immunoassay graphene electrode was modified with anti-AFP antibodies (Ab). Meanwhile, polymer nanoparticles (PFBT dots) were prepared via a nanoprecipitation method. In addition, the AFP was modified by using the PFBT dots and glucose oxidase (GOD), which formed a fluorescent probe (AFP-PFBT-GOD). By the competitive linkage of AFP and AFP-PFBT-GOD onto the anti-AFP modified honeycomb structure electrode, an immunosensor for AFP detection was obtained. During the PEC test, the electrons produced by the catalytic reaction of glucose and GOD can scavenge the photogenerated holes on the PFBT dots, which can reduce the recombination of photogenerated holes and electrons on the PFBT dots. The PEC immunosensor based on a rGO honeycomb structure exhibited a linear detection range of 0.05-100 ng/mL with a detection limit of 0.05 ng/mL. The excellent detection performance of the graphene PEC biosensor provides an opportunity for the early diagnosis of primary liver cancer.
成人血清中的甲胎蛋白（AFP）常出现在早期肝癌中。因此，早期检测AFP浓度异常升高对于原发性肝癌的早期诊断和治疗具有重要意义。在这项工作中，基于还原氧化石墨烯（rGO）蜂窝结构制备了一种用于AFP灵敏检测的光电化学（PEC）电极。通过逐层生物共轭，用抗AFP抗体（Ab）修饰免疫分析石墨烯电极。同时，通过纳米沉淀法制备了聚合物纳米颗粒（PFBT点）。此外，利用PFBT点和葡萄糖氧化酶（GOD）对AFP进行修饰，形成荧光探针（AFP-PFBT-GOD）。通过AFP与AFP-PFBT-GOD在抗AFP修饰的蜂窝结构电极上的竞争连接，获得了一种用于AFP检测的免疫传感器。在PEC测试过程中，葡萄糖与GOD催化反应产生的电子可以清除PFBT点上的光生空穴，这可以减少PFBT点上光生空穴与电子的复合。基于rGO蜂窝结构的PEC免疫传感器的线性检测范围为0.05-100 ng/mL，检测限为0.05 ng/mL。石墨烯PEC生物传感器优异的检测性能为原发性肝癌的早期诊断提供了契机。
