Javad Ghodsi - Department of Physical Chemistry, Faculty of Chemistry, Bu-Ali Sina University, P.O.Box 65174, Hamedan, Iran.
Amir Abbas Rafati - Department of Physical Chemistry, Faculty of Chemistry, Bu-Ali Sina University, P.O.Box 65174, Hamedan, Iran.
Yalda Shoja - Department of Physical Chemistry, Faculty of Chemistry, Bu-Ali Sina University, P.O.Box 65174, Hamedan, Iran.

This work describes the development of a novel biosensor for determination of dopamine in presence of H2O2 and folic acid and uric acid as interferences. The Biosensor was fabricatedfrom a carbon paste electrode modified with electrostatically immobilized hemoglobin on cooper oxide nanoparticles and multi walled carbon nanotube. Because some phenolic compound biosensors were developed using the peroxidase properties of hemoglobin, this can cause thereduction of phenolics in the presence of H2O2. However, the presence of hemoglobin in this electrode led to catalytic oxidation of dopamine at the electrode surface in the presence of H2O2. The biosensor’s performance for phenolic compound detection depends on hemoglobin acting asan electron mediator. This biosensor presents a sensitive response for dopamine. The parameters of the electrode fabrication with experimental conditions for hemoglobin immobilization on CuO nanoparticles were optimized. Linearity for the detection of the dopamine was observed from 5μM to 1 mM. Its detection limit was calculated at ~20 nM. Electrode response reached 80% of its primary response after 30 days. The response time of the developed electrode was about 10 seconds.

Biosensor, cooper oxide nanoparticles, Hemoglobin, Dopamine, Uric acid, Folic acid