关键词: 多酸, 多巴胺, 电化学传感器, 碳糊电极, 循环伏安法

Abstract: Polyoxometalates, a class of anionic clusters with structure diversity and size variability, make them very attractive in many fields such as electrochemistry, catalysis and medicine. The Co(C₁₅N₆H₁₂)₂[PW₁₂O₃₈]·5H₂O（Co[PW₁₂O₃₈]） modified carbon paste electrode was prepared in this work, and its electrochemical performances as the sensor for dopamine detection were characterized with electrochemical impedance spectroscopy, cyclic voltammetry and differential pulse voltammetry. The preparation conditions and test conditions were optimized respectively. Under the optimized conditions, the POMs modified carbon paste electrode exhibited good selectivity and sensitivity in dopamine detection. The linear response range was from 8.0 × 10^-6 mol·L^-1 to 3 × 10^-5 mol·L^-1, and the sensitivity was 0.039 μA·(μmol·L^-1)^-1 with the detection limit of 5.4 × 10^-6 mol·L^-1 (S/N=3). The POMs modified carbon paste electrode used for the dopamine sensing showed good stability, repeatability and anti-interference under the coexistence of ascorbic acid, uric acid and so on. The preparation process was simple, convenient, and low cost, and the electrode obtained had good sensing performance, thus, the present POMs modified electrode demonstrated a promising application for the detection of dopamine.

Key words: polyoxometalates, dopamine, electrochemical sensors, carbon paste electrode, cyclic voltammetry