镍纳米粒子-离子液体修饰碳糊电极的制备及其对多巴胺的测定

Preparation of Ni Nanoparticles-Ionic Liquid Modified Carbon Paste Electrode and Detection of Dopamine

制备了镍纳米粒子-离子液体修饰电极，在0．1moL／L磷酸缓冲溶液（pH6．0）中研究了多巴胺（DA）在修饰电极上的电化学行为。与裸电极相比，DA在该修饰电极上的氧化还原电位明显降低，氧化还原反应的峰电流明显增大，DA的峰电流与其浓度在2．0×10^-8-1．0×10^-4mol／L范围内呈良好的线性关系，检出限为6．5×10^-9mol／L。该修饰电极对抗坏血酸具有明显的抗干扰能力。

A nickel nanoparticles- ionic liquid modified carbon paste electrode were prepared. The electrochemical behavior of dopamine （DA） at above modified electrodes was investigated in 0. 1 mol/ L phosphate buffer solution （pH 6. 0）. Cyclic voltammetry was used to characterize the electrodes in DA solution. The effect of experimental conditions, including mass ratio of nickel nanoparticles and ionic liquid, pH value on DA detection were optimized. The results showed that under the optimal conditions, the overpotential of DA could be obviously reduced at the modified electrode, while the peak current could be increased significantly. A good linear relationship was found between peak current and DA concentration in the range of 2.0×10^-8-1.0×10^-4mol/L with a detection limit of 6.5×10^-9mol/L. The interference of ascorbic acid for the determination of DA could be diminished efficiently.