Electrochemical Oxidation of Dopamine at Polyethylene glycol Modified Carbon Paste Electrode: A Cyclic Voltammetric Study

Polyethylene glycol (PEG) modified carbon paste electrode (CPE) was fabricated for the detection of dopamine and potassium ferricyanide. It showed an excellent sensitivity towards the oxidation of dopamine (DA) in 0.1M phosphate buffer (PBS) at 6.6 pH and potassium ferricyanide in 1 M KCl solution. Effect of scan rate, concentration and pH were studied by the cyclic voltammetric technique. The concentration effect of modifier in the carbon paste electrode also reveals that the change in the electrode interface which would leads to the surface modification of the electrode, enhanced the interaction between the electrode and the cationic charged dopamine. The detection limit of dopamine is 1×10-5 M and the potassium ferricyanide is 1×10-4 M was observed for the PEG/CPE