Modification of Gold Electrodes Using 3-Mercaptopropionic Acid and EDTA as a Copper Sensor Application

Modification of the gold electrode is an alternative method that can be used as a chemical sensor for the analysis of Cu²⁺metal ions. Modification of the gold electrode was carried out by immobilizing 3-mercaptopropionic acid on the surface of the gold electrode using the self-assembled monolayer (SAM) method which was functionalized with EDTA. Gold electrode characterization was performed by Cyclic Voltammetry (CV), Fourier-Transform Infrared Spectroscopy (FTIR), Scanning Electron Microscopy (SEM) and Energy Dispersive Spectrometer (EDS) techniques. The electrode area used is 0.809 cm². Modifications and applications of Au-Bare electrode sensors, Au-3MPA and Au-3MPA-EDTA against the metal ion detection of Cu²⁺ have been successfully performed. The top of the current Cu²⁺ metal ion oxidation state is found in pH 5 among others, 8.07 x 10^-5 A on Au-3MPA-EDTA electrodes, 5.92 x 10^-5 A on Au-3MPA electrodes and 7.42 x 10^-5 A on Au-Bare electrodes at a potential range of 0.35 V.