以柠檬酸三钠为还原剂，在晶种存在的溶液中，通过骤降反应温度调控制备出具有特异形貌的蝌蚪状金纳米颗粒。并以蝌蚪状金纳米颗粒修饰电极，研究了神经递质多巴胺在该修饰电极上的电化学行为。结果显示蝌蚪状金纳米颗粒对多巴胺的氧化具有良好的电催化作用，利用方波伏安法测得DA的检出限测得为0.1 μM。并且检测到多巴胺和其常见干扰物质抗坏血酸的峰电位可以明显地分开，从而实现对此二组分混合溶液的选择性测定。
Fig. 1. (A) TEM image and (D) UV–vis spectrum of as-prepared gold nanotadpoles. (B, C) HRTEM images of (B) head and (C) tail of a gold nanotadpole.
Fig. 2. (A) SW voltammograms of 30 μM DA and 30 μM AA mixture at (a) the bare and (b) the GNT/gold electrodes in 0.1 M PBS (pH 7.0). (B) SW voltammograms of DA (12 μM) at the GNT/gold electrode in 0.1 M PBS (pH 7.0) in the different concentrations of AA (a-g: 45, 55, 65, 75, 85, 95, 105 μM). (C) SW voltammograms of AA (50 μM) at the GNT/gold electrode in 0.1 M PBS (pH 7.0) in the different concentrations of DA (a-e: 4, 6, 8, 10, 12 μM). (D) SW voltammograms of DA and AA mixtures at the GNT/gold electrode in 0.1 M PBS (pH 7.0). DA contents from (a) to (g) are 6, 8, 10, 12, 14, 16, 18 μM, respectively. AA contents from (a) to (g) are 10, 14, 18, 22, 16, 30, 34 μM, respectively.
Lan Huang, Fangfang Peng, Zhirui Guo, Ning Gu. Voltammetric detection of dopamine at gold nanotadpoles modified electrode. Jounral of Nanoscience and Nanotechnology, 2009, 9 1619-1622
