Electrochemical detection of dopamine at poly(solochrome cyanine)/Pd nanoparticles doped modified carbon paste electrode and simultaneous resolution in the presence of ascorbic acid and uric acid: a voltammetric method

Abstract

A novel chemically modified electrode was constructed based on the electrodeposition of palladium nanoparticles (PdNps) on to a poly(solochrome cyanine) (polySCCy) film coated carbon paste electrode (CPE). Cyclic voltammetry (CV), differential pulse voltammetry (DPV), and electrochemical impedance spectroscopy (EIS) were used to characterize the properties of the modified electrode. The polySCCy/PdNPs/CPE was used for the impressionable, individualized determination and simultaneous resolution of dopamine (DA), ascorbic acid (AA) and uric acid (UA) in 0.1 M acetate buffer solution (ABS) of pH 5.0 by employing CV and DPV. The polySCCy/PdNPs/CPE exhibited strong electrocatalytic activity towards the oxidation of a mixture solution of DA, AA and UA with obvious redox potentials. The overlapping voltammetric response of biomolecules were separated into three well resolved oxidation peaks for DA, AA and UA with lower oxidation potentials and significant increase in the anodic peak currents in the presence of polySCCy/PdNPs/CPE by using CV and DPV. The results showed good sensitivity, selectivity and high reproducibility of the electrosynthesized polymer nanoparticles inclusion electrode. The limit of detection, limit of quantification and correlation coefficient of DA at polySCCy/PdNPs/CPE were 1.87 μM, 6.24 μM and 0.99375, respectively. The developed chemical sensor is ideal for the analysis of DA in pharmaceutical formulations providing satisfactory results. The interfacial electron transfer rate of DA was studied by EIS.