Electrochemical Determination of Tyrosine in the Presence of Dopamine and Uric Acid at the Surface of Gold Nanoparticles Modified Carbon Paste Electrode

چکیده مقاله

A gold nanoparticles modified carbon paste electrode (GN-CPE) was u sed as a highly sensitive electro - chemical sensor for determination of tyrosine (Tyr), dopamine (DA) and uric acid (UA) in phosphate buffer solution (PBS). The study and measurements were carried out by using cyclic voltammetry (CV), differential pulse voltammetry (DPV) and chronoamperometry methods. In DPV, the GN-CPE could sep - arate the oxidation peak potentials of DA and UA present in the same solution, though at the unmodified CPE the peak potentials were indistinguishable. The prepared electrode showed voltammetric responses with high sensitivity and selectivity for Tyr, DA and UA in optimal conditions, which makes it very suit - able for simultaneous determination of these compounds. The calibration curves for Try, DA and UA were linear for the concentrations of each species. The pr oposed voltammetric approach was also applied to the determination of Tyr concentration in human serum as a real sampl