Highly sensitive and selective dopamine biosensor based on a phenylethynyl ferrocene/graphene nanocomposite modified electrode

Analyst. 2012 Oct 7;137(19):4577-83. doi: 10.1039/c2an35708a.

Abstract

A new ferrocene derivative (1-[(4-amino) phenylethynyl]ferrocene, Fc-NH(2)) was synthesized for the first time. The ferrocene derivative molecule contained the phenylethynyl skeleton, ferrocene and amino groups with excellent electrochemical properties. The graphene/Fc-NH(2) nanocomposite was prepared by mixing graphene solution and Fc-NH(2) solution in one pot and the nanocomposite was utilized to construct a Nafion/graphene/Fc-NH(2) modified glassy carbon electrode (GCE). The ferrocene derivative immobilized on the graphene can enhance the charge-transport ability of the nanocomposite, stabilize the graphene and prevent the leakage of ferrocene. The detection signal of dopamine (DA) was significantly amplified on the Nafion/graphene/Fc-NH(2)/GCE. It was experimentally demonstrated that the signal enhancement results from the synergy amplification effect of graphene and the Fc-NH(2). The oxidation peak currents of DA were linearly related to the concentrations in the range of 5 × 10(-8) to 2 × 10(-4) M with the detection limit of 20 nM in the absence of uric acid (UA) and ascorbic acid (AA). In the presence of 10(-3) M AA and 10(-4) M UA, the linear response range was 1 × 10(-7) to 4 × 10(-4) M, and the detection limit was 50 nM at S/N = 3. Using the proposed Nafion/Fc-NH(2)/graphene/GCE, DA was successfully determined in real samples with the standard addition method.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Ascorbic Acid / chemistry
  • Biosensing Techniques*
  • Dopamine / analysis*
  • Electrochemical Techniques*
  • Electrodes
  • Ferrous Compounds / chemistry*
  • Fluorocarbon Polymers / chemistry
  • Graphite / chemistry*
  • Metallocenes
  • Nanocomposites / chemistry*
  • Oxidation-Reduction
  • Uric Acid / chemistry

Substances

  • Ferrous Compounds
  • Fluorocarbon Polymers
  • Metallocenes
  • Uric Acid
  • perfluorosulfonic acid
  • Graphite
  • Ascorbic Acid
  • ferrocene
  • Dopamine