金纳米管阵列修饰玻碳电极用于示差脉冲伏安法测定多巴胺

Determination of Dopamine by Differential Pulse Voltammetry with Au Nanotubes Array Modified Glassy Carbon Electrode

以聚碳酸酯模板为工作电极,采用电沉积法从氯金酸和高氯酸溶液中制得金纳米管。将沉积了金纳米管的模板固定在玻碳电极表面,用氯仿溶解7min将模板溶解。制得了金纳米管阵列修饰电极,采用循环伏安法和微分示差脉冲伏安法研究了多巴胺在修饰电极上的电化学行为,结果表明:多巴胺在该电极上有一对氧化还原峰,提出了示差脉冲伏安法测定多巴胺的方法。在电位+0.170V处,多巴胺的氧化峰电流与其浓度在4.95×10-7～9.9×10-2 mol.L-1范围内呈线性关系,方法的检出限(3σ)为1.06×10-8 mol.L-1。应用该修饰电极测定人尿样品中多巴胺含量,加标回收率在96.9%～101.4%之间,相对标准偏差(n=5)在3.1%～4.2%之间。

Using polycarbonate template as Working electrode, gold nanotubes were prepared by electro deposition from a solulion of HAuCl, and HCIO. The template deposited with Au nanotubes was fixed on surface of glassy carbon electrode （GCE） and the GCE modified with arrayed Au nanotubes was prepared by dissolving the template from the electrode with CHCI：; for 7 min. The electrochemical behavior of dopamine （DA） at the modified electrode was studied by cyclic voltammetry （CV） and differential pulse voltammetry （DPV）. It was found that DA showed a pair of oxidation and reduction peaks at the modified electrode. A sensitive method for determination of DA by DPV was proposed. 1,inear relationship between values of oxidation peak current at ＋ 0. 170 V and concentration of DA was obtained in the range of 4.95×10^- 7 --9.9×10^-2mol·L^-1 , with detection limit （3σ） of l. 06×10^-8mol·L^-1. The proposed method was applied to the determination of DA in human urine, giving values of recovery and RSD＇s （n=5） in ranges of 96.9% 101.4% and 3. 1%--4.2% respectively.