Synthesis of MgFe2O4 nanoparticles and MgFe2O4 nanoparticles/CPE for electrochemical investigation of dopamine

Magnesium ferrite nanoparticles (MgFe2O4 NPs) were prepared by a solution based method using magnesium sulphate (MgSO4), ferrous sulphate (FeSO4), dl serine and NaOH as a precipitant and the obtained precipitation was calcinated under 500 degrees C for 4 h. The resulting material was characterized by using X-ray diffractometry (XRD) and scanning electron microscopy (SEM). The MgFe2O4 NPs were used for preparation of MgFe2O4 NPs/carbon paste electrode (MgFe2O4 NPs/CPE) and applied for electrochemical investigation of dopamine (DA) which exhibits good electrocatalytic activity for investigation of DA at physiological pH 7.4. The effect of pH range from 5.5 to 8.0 was studied and the result shows that the redox peak current was maxima at pH 7.5 and the redox peak was pH dependent with a slope of 0.061 V/pH. The scan rate effect was found to be an adsorption-controlling electrode process. The electrocatalytic currents increased linearly with an increase in DA concentration in the range 0.1-1.2 mu M and the detection limit was found to be 7.7 x 10(-8) M. The proposed method was successfully applied to the determination of DA in injection samples.