• 文献标题:   Guanine-Decorated Graphene Nanostructures for Sensitive Monitoring of Neuron-Specific Enolase Based on an Enzyme-Free Electrocatalytic Reaction
  • 文献类型:   Article
  • 作  者:   LI GZ, TIAN F
  • 作者关键词:   guaninedecorated graphene nanostructure, bioelectrocatalytic reaction, neuronspecific enolase, electrochemical immunosensor
  • 出版物名称:   ANALYTICAL SCIENCES
  • ISSN:   0910-6340 EI 1348-2246
  • 通讯作者地址:   Chongqing Three Gorges Univ
  • 被引频次:   6
  • DOI:   10.2116/analsci.29.1195
  • 出版年:   2013

▎ 摘  要

A new and enzyme-free electrochemical immunoassay protocol was developed for the sensitive electronic monitoring of neuron-specific enolase (NSE) on a monoclonal mouse anti-human NSE antibody (mAb)-modified glassy carbon electrode, using guanine-decorated graphene nanostructures (GGN) as nanotags. To construct such an enzyme-free immunoassay format, guanine and polyclonal rabbit anti-human NSE antibody (pAb) were co-immobilized on the graphene nanostructures through the carbodiimide coupling. Based on a sandwich-type immunoassay mode, the assay was carried out in 0.1 M pH 7.4 PBS containing 5 mu M Ru(bpy)(3)(2+) through the catalytic oxidation of Ru(bpy)32+ toward the guanine on the GGN. The presence of graphene nanostructures increased the immobilized amount of guanine, thus amplifying a detectable electronic signal. The covalent conjugation of guanine and pAb on the GGN resulted in a good repeatability and intermediate reproducibility down to 9.5%. Under optimal conditions, the dynamic concentration range of the developed immunoassay spanned from 0.005 to 80 ng mL(-1) NSE with a detection limit of 1.0 pg mL(-1) at the 3S(blank) level. In addition, the methodology was evaluated by assaying the spiking serum samples, and the relative standard deviation (RSD) between the electrochemical immunoassay and a commercialized enzyme-linked immunosorbent assay (ELISA) were 2.8 - 7.0%.