PhosphoMolybdic Acid and Poly(Paraphenylenediamine) Modified Carbon Paste Electrode using Voltammetric Determination of Dopamine and Uric Acid

A polymerized film of PhosphoMolybdic Acid (PMA)/Poly(Paraphenylene diamine) (PPD) was prepared. The surface of carbon paste electrode was polymerized with the film of PhosphoMolybdic Acid (PMA) and paraphenylenediamine in PBS buffer solution of physiological pH 7.4 by the process of ionic deposition and electro-polymerization. Electrochemical identifications were studied by cyclic voltammetry. This Modified Carbon Paste Electrode (MCPE) was used to investigate DP and UA by CV and DPV techniques, number of parameters affecting the electrocatalytic activity of modified CPE such as effect of pH, scan rate, and concentration were studied. The detection limits of dopamine (DP) and Uric Acid(UA) were calculated by CV as 1.3550μM and 4.230μM respectively. The high electro catalytic activity of PMA and PPD modified carbon paste electrodes expected to be highly applicable in the field of electro analytical chemistry for the determination of other bio active molecules or neurotransmitters. The modified electrode showed higher sensitivity and selectivity for the simultaneous determination of DP and UA, and fouling effect is also eliminated by this MCPE.