Electrochemical response of dopamine at a penicillamine self-assembled gold electrode

Bioelectrochemistry. 2001 Nov;54(2):169-75. doi: 10.1016/s1567-5394(01)00125-6.

Abstract

The penicillamine (Pen) self-assembled monolayer (SAM) modified gold electrode (Pen/Au) is demonstrated to catalyze the electrochemical response of dopamine (DA) by cyclic voltammetry. A pair of well-defined redox waves was obtained and the calculated standard rate constant (k(s)) is 3.88 x 10(-3) cm/s at the self-assembled electrode. The electrode reaction is a quasi-reversible process. The oxidation peak of DA can be used to determine the concentration of DA. The peak current and the concentration of DA are a linear relationship in the range of 2.0 x 10(-5) M to 8.0 x 10(-4) M. The detection limit is 4.0 x 10(-6) M. By ac impedance spectroscopy the apparent electron transfer rate constant (k(app)) of Fe(CN)(3-)/Fe(CN)(4-) at the Pen/Au electrode was obtained as 2.08 x 10(-5) cm/s. The Pen SAM was characterized with X-ray photoelectron spectroscopy (XPS), grazing angle FT-IR spectroscopy and contact angle goniometer.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Catalysis
  • Dopamine / chemistry*
  • Dopamine / metabolism
  • Drug Interactions
  • Electrochemistry
  • Electrodes
  • Gold
  • Humans
  • Kinetics
  • Oxidation-Reduction
  • Penicillamine / chemistry*
  • Penicillamine / metabolism
  • Spectroscopy, Fourier Transform Infrared
  • Spectrum Analysis
  • X-Rays

Substances

  • Gold
  • Penicillamine
  • Dopamine