Meng Yubo, Song Yingpan, Guo Chuanpan, Cui Bingbing, Ji Hongfei, Ma Zongzheng
College of Mechanical Engineering, Henan University of Engineering No. 1, Xianghe Road, Longhu Town Zhengzhou Henan 451191 P. R. China
Henan Provincial Key Laboratory of Surface and Interface Science, Zhengzhou University of Light Industry No. 136, Science Avenue Zhengzhou Henan 450001 P. R. China
RSC Adv. 2019 May 1;9(24):13431-13443. doi: 10.1039/c9ra01847f. eCollection 2019 Apr 30.
Partially- and fully-unzipped nitrogen-doped carbon nanotubes (NCNTs) were prepared by unzipping pristine NCNTs and three carbon nanostructures were applied to support Au nanoparticles (AuNPs) to form nanocomposites (Au/NCNTs, Au/PU-NCNTs, and Au/FU-NCNTs). The electrochemical behavior and the electrocatalytic activities of the nanocomposite-modified electrodes were examined. The oxygen functional groups, doped N content, and AuNP loaded concentrations are dependent on the unzipping-degree and then affect the electrochemical response and electrocatalytic performance of the electrodes. Besides, the three nanocomposites were also used for the immobilization of carcinoembryonic antigen (CEA) aptamer strands and applied for the detection of CEA. The Au/FU-NCNTs possess the optimal electrocatalytic activity and biosensing performance for the biomolecules and CEA, which is attributed to the maximum loaded AuNPs, the largest specific surface areas and the most active sites. The Au/FU-NCNT-based electrochemical aptasensor exhibits high sensitivity with a low detection limit of 6.84 pg mL within a broad linear range of CEA concentration from 0.01 to 10 ng mL. All of these results indicate that the Au/FU-NCNTs may be a potential support for construction of aptasensors with high electrochemical effect and can be employed in the fields of biosensing or biomedical diagnosis.
通过对原始氮掺杂碳纳米管（NCNTs）进行解链制备了部分解链和完全解链的氮掺杂碳纳米管，并应用三种碳纳米结构负载金纳米颗粒（AuNPs）以形成纳米复合材料（Au/NCNTs、Au/PU-NCNTs和Au/FU-NCNTs）。研究了纳米复合修饰电极的电化学行为和电催化活性。氧官能团、掺杂氮含量和负载的AuNP浓度取决于解链程度，进而影响电极的电化学响应和电催化性能。此外，这三种纳米复合材料还用于固定癌胚抗原（CEA）适配体链，并应用于CEA的检测。Au/FU-NCNTs对生物分子和CEA具有最佳的电催化活性和生物传感性能，这归因于最大负载量的AuNPs、最大的比表面积和最多的活性位点。基于Au/FU-NCNT的电化学适配体传感器具有高灵敏度，在CEA浓度从0.01到10 ng mL的宽线性范围内检测限低至6.84 pg mL。所有这些结果表明，Au/FU-NCNTs可能是构建具有高电化学效应的适配体传感器的潜在载体，可用于生物传感或生物医学诊断领域。
