• 文献标题:   Electrochemical determination of sulfamethazine using a gold electrode modified with multi-walled carbon nanotubes, graphene oxide nanoribbons and branched aptamers
  • 文献类型:   Article
  • 作  者:   HE BS, LI M, LI MN
  • 作者关键词:   aptamer, aus bond, recognition element, fe cn 6 34, electrodeposited gold nanoparticle
  • 出版物名称:   MICROCHIMICA ACTA
  • ISSN:   0026-3672 EI 1436-5073
  • 通讯作者地址:   Henan Univ Technol
  • 被引频次:   0
  • DOI:   10.1007/s00604-020-04244-4
  • 出版年:   2020

▎ 摘  要

An aptasensor assay for sulfamethazine is introduced based on a gold electrode modified with multi-walled carbon nanotubes@graphene oxide nanoribbons (MWCNTs@GONRs) nanocomposites. The MWCNTs@GONRs nanocomposites were synthesized by a chemical longitudinal partially unzipping method. Its properties are characterized by scanning electron microscope (SEM), energy dispersive spectrometric analysis (EDS), transmission electron microscope (TEM) and X-ray diffraction (XRD). In the presence of sulfamethazine, the conformation of the aptamer changes and a G-quadruplex structure is formed. It inhibits the electron transfer of the redox probe [Fe(CN)(6)](3-/4-) on the electrode surface, causing weakening of the peak current response at the peak potential of 0.17 V (vs. Ag/AgCl). Using differential pulse voltammetry, a linear response was obtained for sulfamethazine concentrations in the range 0.01 similar to 50 ng mL(-1) with a detection limit of 5.2 pg mL(-1). Schematic representation of an electrochemical aptasensor for sulfamethazine determination. A gold electrode is modified with multi-walled carbon nanotubes@graphene oxide nanoribbons to improve the electrode performance. When the aptamer binds to sulfamethazine to form G-quadruplex, the peak current response decreases.