Determination Of Dopamine With DL-Arginine/Graphene Modified Electrode

Dopamine(DA) is a neurotransmitters and involved in many physiological activities ofhuman body and mammals. The disbalance of DA content in human body would lead toHuntington’s Diseases and Parkinson’s disease.Dopamine is called a kind of happinesssubstance,and it can be used to cure depression,shock and excite heart.Its content and humanhealth are closely related, and establishing a method with simplicity, convenience, fastmeasurement of human dopamine content is necessary. Dopamine was determined with theprepared amino acid/graphene modified electrode, which is simple, rapid, high sensitivity, inthis experiment.Stable graphene solution was prepared by improved Hummers method at roomtemperature in this experiment, and X ray diffraction (XRD), transmission electronmicroscopy (TEM), scanning electron microscopy (SEM) were used to characterize thegraphene. After the modified electrode is in expected state, and then optimize the modifiedelectrode and the determination condition.In the PBS(pH=6.0) buffer solution using thedifferential pulse voltammetry was used to sweep the objective determined material dopaminehydrochloride solution in the potential range from-1V to1V, the sweeping speed is100mV/sand enrichment time200s, both amino acid and graphene are modified on the surface ofelectrode to get a new method determining DA.The experiment result shows that the sensitiveoxidation peak of DA is at0.189V, and it is good linear relationship in the range from1.0×10-6to5.0×10-4mol/L with the concentration, the correlation coefficient is R=0.9981,the lowdetection limit is3.0×10-7mol/L,meanwhile some other materials which will affect the DAdetermination result were involved in this paper,the results show that the interfering substancecan be missed and the experiment result is satisfactory at last.