Abstract
In this research the electrochemistry of methyldopa (MDOP) was studied by electrochemical methods at a carbon paste electrode modified by Fe:Co nano-alloy (Fe:Co/NL/CPE). For this goal we describe synthesis of Fe:Co/NL using ball mill method and then characterize with different methods such as scanning electron microscopy (SEM) and X-ray diffraction (XRD) in the first step. The oxidation peak potential of the MDOP at a surface of Fe:Co/NL/CPE appeared at 480 mV that was about 100 mV lower than the oxidation peak potential at the surface of the unmodified carbon paste electrode (CPE) under similar condition. Result shows for the mixture containing MDOP and hydrochlorothiazide (HCTZ), the peaks potential well separated from each other. Under the optimized conditions, the oxidation peak current of MDOP showed linear dynamic range (in 0.06-600 mu M) with a detection limit of 0.03 mu M, using square wave voltammetry (SWV) method. The proposed sensor was successfully applied for the determination of MDOP in real samples such as tablet, serum and urine.