Direct voltammetric determination of gold nanoparticles using graphite-epoxy composite electrode

• Published in: Electrochimica acta Vol. 50; no. 18; pp. 3702 - 3707
• Main Authors: Pumera, Martin, Aldavert, Marta, Mills, Chris, Merkoçi, Arben, Alegret, Salvador
• Format: Journal Article
• Language: English
• Published: Oxford Elsevier Ltd 10-06-2005; Elsevier
• Subjects: Analytical chemistry; Chemistry; Differential pulse voltammetry; Exact sciences and technology; General, instrumentation; Gold nanoparticles; Graphite-epoxy composite; Stripping voltammetry; Stripping voltammetry; Graphite-epoxy composite; Gold nanoparticles; Differential pulse voltammetry; Performance evaluation; Electrode adsorption; Gold; Epoxy resin; Transition metal; Chemical sensor; Metal particle; Electrochemical detector; Graphite; Composite electrode; Cylindrical electrode; Colloid particle
• ISSN: 0013-4686; 1873-3859
• DOI: 10.1016/j.electacta.2005.01.035

A new voltammetric method for a direct determination of gold nanoparticles, based on adsorption and electrochemical detection of colloidal gold, is described. In this protocol, the absorption of gold nanoparticles onto the rough surface of graphite-epoxy composite electrode is followed by their electrochemical oxidation in 0.1
M HCl medium at a potential of +1.25
V. The resulting tetrachloroaurate ions generated near the electrode surface are detected by differential pulse voltammetry (DPV). The DPV response is linear in the range from 4.7
×
10
8 to 4.7
×
10
11
nanoparticles
cm
−3 with a limit of detection of 1.8
×
10
8
gold nanoparticles
cm
−3. The surface characteristics of the composite electrode are investigated and the parameters that affect the complete analytical detection process of gold nanoparticles are optimized.