Abstract
The electrochemical has been constructed based on Co3O4/rGO nanocomposite in presence of CTAB modified carbon paste electrode (CPE) and was developed for the simultaneous determination of dopamine, uric acid and folic acid at physiological pH 7.0 (PBS, 0.1 M). The physico-chemical analysis of nanocomposite was characterized by FT-IT, PXRD, SEM, TEM and EDX. The modified sensor showed well defined and stable reversible peak couple in both alkaline and aqueous solution. From the differential pulse voltammetry (DPV), the electrochemical sensor showed excellent electrocatalytic activity for the oxidation of dopamine, limit of detection (LOD) and limit of quantification (LOQ) of DA are calculated to be 2.8 μM and 10 μM, respectively. The Co3O4/rGO/CTAB MCPE showed an efficient electron mediating behavior with well defined oxidation peak potentials between DA to UA and UA to FA were 0.12 V and 0.39 V, respectively. From the cyclic voltammetry the results obtained for the linear calibration plots and the limit of detection of DA, UA and FA were calculated to be 7 μM, 94 μM and 19 μM, respectively. The developed sensor was successfully employed to sensing of DA in real samples.