SmHCF/(MWCNT) nano structures modified glassy carbon (GC) electrode was used as electrochemical sensor for the electro oxidation of dopamine. Our strategy was the combination of high electrocatalytic property of SmHCF to electroactive biomolecule and high conductivity, surface area and adhesive properties of carbon nanotubes. The presence of SmHCF nanoparticles and MWCNT were approved by Scanning electron microscopy (SEM) and cyclic voltammetry (CV). The electrocatalytic performance of GC, SmHCF-GC, MWCNT-GC and SmHCF-MWCNT-GC electrodes toward dopamine was compared and the results cleared the enhanced electrocatalytic activity of SmHCF-MWCNT-GC (lowering the potential of the oxidation process and increased oxidation current peak.) relative to others. This unique combination leads to improvement of the sensitivity of dopamine determination. The differential pulse voltammetry was used for quantitative determination of dopamine. The linear dynamic range relationship between oxidation peak currents and dopamine concentration was 2× 10-7 - 5× 10-6 (slope = 24.187 µAµM-1) with the detection limit of 6× 10-8 for DA. The sensitivity of the electrode was 24.187 µAµM-1 that it is very high relative to reported works. The relative standard deviation (RSD) of the reproducibility (5 modified electrodes), repeatability (successive 10 times), and stability (50 days) of the modified electrode were 3%, 3% and 2.5% respectively. The accuracy and selectivity of the modified electrode were indicated in the real sample as human serum samples and in the presence of possible interfering agents. Good selectivity and recovery were observed for modified electrode. پرونده مقاله