Docosyltrimethylammonium chloride modified glassy carbon electrode for simultaneous determination of dopamine and ascorbic acid

作者：Luo, Li-Qiang^*; Li, Qiu-Xia; Ding, Ya-Ping; Zhang, Ying; Shen, Xia

来源：Journal of Solid State Electrochemistry, 2010, 14(7): 1311-1316.

DOI：10.1007/s10008-009-0936-9

• Docosyltrimethylammonium chloride
• Simultaneous determination
• Dopamine
• Ascorbic acid

A glassy carbon electrode (GCE) modified with docosyltrimethylammonium chloride (DCTMACl) is used for simultaneous determination of dopamine (DA) and ascorbic acid (AA) using differential pulse voltammetry (DPV) technique in 0.10 mol center dot L(-1) phosphate buffer solution of pH 5.0. The cationic surfactant DCTMACl modified film has a positive charge. DA exists as the positively charged species, whereas AA is the negatively charged one in the solution. Thus, at DCTMACl film-modified GCE, the oxidation peak potential of AA shifts toward less negative potential and the peak current of AA increases a little, while the oxidation peak potential of DA shifts toward more positive potential and peak current decreases greatly in comparison with that on bare electrode. The two anodic peaks are separated around 200 mV. Under optimal conditions, the catalytic peak currents obtained from DPV increase linearly with concentrations of DA and AA in the ranges of 1.0 x 10(-5) to 1.0 x 10(-3) mol center dot L(-1). This electrode has good reproducibility, high stability in its voltammetric response, and low detection limit (micromolar) for both AA and DA. The modified electrode has been applied to the determination of DA and AA in injection.

• 出版日期2010-7
• 单位上海大学