Electrochemical sensor based on SmHCF/multiwalled carbon nanotube modified glassy carbon electrode for dopamine

Document Type : Original Research Paper


1 Faculty of Chemistry, Kharazmi (TarbiatMoallem) University, Tehran, Iran

2 Nuclear Fuel Cycle School, Nuclear Science & Technology Research Institute, P.O. Box 14155-1339, Tehran, Iran



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 SmHCFnanoparticles and
MWCNT was approved by Scanning electron microscopy (SEM) and cyclic
voltammetry (CV). The electrocatalytic performance of GC, SmHCF-GC, MWCNTGC
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 the 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 of6× 10-8 forDA.
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 the modified electrodes.