Zhou Chunyang, Liu Dali, Xu Lin, Li Qingling, Song Jian, Xu Sai, Xing Ruiqing, Song Hongwei
State Key Laboratory on Integrated Optoelectronics, College of Electronic Science and Engineering, Jilin University, 2699 Qianjin Street, Changchun, 130012, P. R. China.
1] State Key Laboratory on Integrated Optoelectronics, College of Electronic Science and Engineering, Jilin University, 2699 Qianjin Street, Changchun, 130012, P. R. China [2] The State Key Laboratory of Bioelectronics, Southeast University, 210096 P. R. China.
Sci Rep. 2015 Apr 24;5:9939. doi: 10.1038/srep09939.
A simple and accurate label-free amperometric immunosensor for α-fetoprotein (AFP) detection is developed based on gold nanorods (GNRs) with different aspect ratio and compared with gold particles (GNPs). The positively charged GNRs and GNPs due to the surface immobilized cetyltrimethyl ammonium bromide (CTAB) can adsorb the negatively charged AFP antibody (Ab) directly. The presence of the GNRs not only enhanced the immobilized amount of biomolecules, but also improved the electrochemical properties of the immunosensor. With the aid of GNRs, the electrochemical signal was greatly enhanced in comparison with GNPs. Under optimal conditions, the proposed immunosensor could detect AFP in a linear range from 0.1 to 200 ng/mL with a detection limit of 0.04 ng/mL (signal-to-noise ratio = 3), and it also possessed good reproducibility and storage stability. Moreover, the detection of AFP in five human serum samples also showed satisfactory accuracy. The proposed methodology was potentially attractive for clinical immunoassay.
基于不同纵横比的金纳米棒（GNRs）开发了一种用于检测甲胎蛋白（AFP）的简单准确的无标记电流型免疫传感器，并与金颗粒（GNPs）进行了比较。由于表面固定有十六烷基三甲基溴化铵（CTAB），带正电荷的GNRs和GNPs可以直接吸附带负电荷的AFP抗体（Ab）。GNRs的存在不仅增加了生物分子的固定量，还改善了免疫传感器的电化学性质。借助GNRs，与GNPs相比，电化学信号大大增强。在最佳条件下，所提出的免疫传感器能够在0.1至200 ng/mL的线性范围内检测AFP，检测限为0.04 ng/mL（信噪比=3），并且还具有良好的重现性和储存稳定性。此外，对五份人血清样本中AFP的检测也显示出令人满意的准确性。所提出的方法对临床免疫分析具有潜在的吸引力。
