Determination of dopamine and uric acid in presence ascorbic acid by means a carbon paste electrode modified with nanoclay- ionic liquid

Dopamine (DP) is one of the catecholamine which distributed in the brain tissues and acts as an important neurotransmitters in mammalian brain tissues and fluids [1-2].Uric acid (UA) is the primary produced of purine in human body [3].Ascorbic acid (AA) is an important antioxidant which is used for the prevention and treatment of cancer and common cold [4]. The aim of this study was to develop a new sensitive method for simultaneously the determination of DP, UA in presence AA in serum samples. Using the cyclic voltammetry and differential pulse voltammetry as diagnostic methods, this study describes the electrochemical behavior of drugs, at the NC-IL-CPE electrode. The response currents are is linear in DP concentration range of 20.0μM to 200.0 μM,and 200.0μM to 600.0 μM , the UA concentrations from 5.0 to 600.0 μM,and the AA from 100.0-2000.0 μM concentrations the detection limits for DP and UA are estimated to be about, 2.25 μM and 3.72 μM (S/N = 3), respectively. Repeatability was examined for 7 replicate measurements of 50 μM DP, 85μM UA in presence 100μM AA the relative standard deviation, RSD of 3.1% for DP and 2.8% for UA, respectively, was obtained, indicating a high degree of reproducibility.