Abstract
A nanostructured polymer film incorporated gold nanoparticles modified electrode was fabricated. The fabrication process involved a previous electropolymerization of aspartic acid and followed by the eletrodeposition of gold nano-particles on the glassy carbon electrode. The resulting poly (aspartic acid)-nanogold modified electrode (PAA- nano-Au/GCE) was characterized by scanning electron microscopy (SEM) and electrochemical impedance spectros-copy (EIS). A higher catalytic activity was obtained to electrocatalytic oxidation of dopamine (DA), ascorbic acid (AA) and uric acid (UA) due to the enhanced peak current and well-defined peak separations compared with three, bare GCE, PAA/GCE and nano-Au/GCE. Simultaneous determination of DA, AA, and UA were studied by voltammetry. The linear range of 5.0 × 10-7 - 1.0 × 10-4 M for DA, 5.0 × 10-6 - 2.0 × 10-3 M for AA and 5.0 × 10-6 - 1.0 × 10-3 M for UA was obtained. The detection limit was calculated for DA, AA and UA as being 6.5 × 10-8 M, 5.6 × 10-7 M and 3.0 × 10-7 M, respectively (S/N = 3). The practical application of the present modified electrode was demonstrated by the determination of DA, AA and UA in calf serum and fetal calf serum samples.
Highlights
Dopamine (DA) is an important neurotransmitter molecule and an indispensable intermediate species in human metabolism [1,2,3]
A higher catalytic activity was obtained to electrocatalytic oxidation of dopamine (DA), ascorbic acid (AA) and uric acid (UA) due to the enhanced peak current and well-defined peak separations compared with three, bare GCE, PAA/GCE and nano-Au/GCE
We demonstrated that the potential range would affect the electropolymerization, only at high potential over 1.5 V, the oxidation of the amino group could turn into its corresponding cation radical, and these cation radicals can form carbon-nitrogen links at the carbon electrode surface
Summary
Dopamine (DA) is an important neurotransmitter molecule and an indispensable intermediate species in human metabolism [1,2,3]. We reported the electrodeposition preparation of nanogold modified glassy carbon electrode and its application to simultaneous voltammetric determination of dihydroxyhenzene isomers [26]. Preparation of composite electrodes by incorporation of metal nanoparticles or polymers on the electrode surface can be extensively enhance the catalytic activity of the electrodes towards electrochemical behaviors of many biologically importance molecules [25,28]. We report for the first time a simultaneous voltammetric determination of DA, AA and UA using a poly aspartic acid incorporated nanogold particles modified glassy carbon electrode (PAA-nano-Au/GCE). It illustrated that the PAA-nano-Au/GCE can catalytically oxidize DA, AA and UA simultaneously, but separate their oxidation peaks distinctly. Compared with the existing reports about simultaneous determination of DA, AA and UA (shown in Table 1), the proposed method is much more convenient to prepare the modified electrode, the selectivity and stability is better
Sign-in/Register to view highlights & summary Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
