Application of the Disorganized Monolayer Gold Electrode to Copper Determination in White Wine

Abstract

Underpotential deposition stripping voltammetry (UPD‐SV) at disorganized monolayer‐modified gold electrodes was employed for the determination of copper in white wine. Spontaneous adsorption of 2‐mercaptoethane sulfonate (MES, HS–CH₂–CH₂–SO₃ ⁻) onto gold electrodes results in formation of a porous, disorganized monolayer. This protects the electrode surface from organic matter present in the wine which otherwise adsorbs onto the electrode surface and passivates it. Detection of copper was performed by UPD‐SV in acidified wine matrix. The approach was validated by the analysis of two spiked wine samples, yielding recoveries of 96% and 95% with relative standard deviations of 7% and 16%, respectively. These results demonstrate the ability of disorganized monolayer‐modified gold electrodes for detection of copper in white wine.

Keywords:

• Anodic stripping voltammetry
• Modified electrode
• Underpotential deposition
• 2‐Mercaptoethane sulfonate
• Copper
• White wine

Acknowledgments

The Royal Society of Chemistry is thanked for a studentship under the “RSC/EPSRC Analytical PhDs” scheme.