Elaheh Movahedi - Department of Chemistry, University of Sistan & Baluchestan, Zahedan, Iran
Alireza Rezvani - Department of Chemistry, University of Sistan & Baluchestan, Zahedan, Iran

Dopamine (DA), an important catecholamine neurotransmitter, which is widely distributed in the mammalian central nervous system, plays a significant role in human metabolism as well as inthe renal systems by participating in many biochemical reactions, such as reward-related behavior, movement and exciting signals transmission. Various neurodegenerative diseases are due to the abnormality of DA, including Schizophrenia and Parkinsonism Senile dementia [1].Therefore, it is of critical importance in applying in diagnostic and medical investigations.Various methods have been developed for the determination of DA. Electrochemical method has drawn much attention by offering advantages including simplicity, good stability and low costs[2]. Transition metal complexes are also usually employed as electrochemical mediators because of their catalysis in low potential, reversible property of electrode reaction and peculiar biological function [3]. Considering these precedents, it emerges that it is advantageous to enhance the electrochemical performance of the electrode by modifying the transition metal complexes on the electrode surface. Because of easy preparation, convenient modification andthe versatility of electrochemical sensors based on transition metal complexes [cu(phen)2(L)]2+(phen=1,10-phenanthroline, L=4,5-diazafluoren-9-one) coupled was used as a modifier to fabricate a chemically modified electrode in this paper. The electrode modified with[cu(phen)2(L)]2+ showed good electrocatalytic activities toward the oxidation of DA and possibleapplicability for DA determination in real samples. Under the optimum experimental conditions, the linear calibration curve was obtained in the range from 2.5 to 500 μmol·L-1 with a lowdetection limit of 1.50 μmol·L-1 (at a signal-to-noise ratio of 3). Keywords: Dopamine, Transition metal complex, 1,10-phenanthroline,

Dopamine, Transition metal complex, 1,10-phenanthroline, 4,5-diazafluoren-9-one