?-Cyclodextrin Incorporated Carbon Nanotube-coated Electrode for the Simultaneous Determination of Dopamine and Epinephrine

An α-cyclodextrin (α-CD) incorporated carbon nanotube (CNT)-coated electrode was fabricated and applied to the simultaneous determination of dopamine (DA) and epinephrine (EP). It has been found that the modified electrode shows strong catalytic effects on the electro-separation of DA and EP, and the cathodic potential difference between DA and EP is about 390 mV. The reducing peak current is proportional to DA and EP concentrations in the range of 2.0×10-6–1.0×10-3 and 1.0×10-6–1.0×10-3 mol·L-1, respectively. Their detection limits can reach 1×10-6 and 5×10-7 mol·L-1, respectively. Because the oxidation of ascorbic acid (AA) is an irreversible reaction in α-CD/CNT film, the interference of AA in determination of DA and EP is eliminated.