CdTe量子点碳糊修饰电极的制备及多巴胺测定

Preparation of CdTe quantum dots modifiedcarbon paste electrode and the determination of dopamine

在碳糊中加入CdTe量子点制成修饰电极(CdTe/CPE),并研究了多巴胺(DA)在该修饰电极上的电化学行为。实验结果表明:在pH 7.0 PBS缓冲液中,电极上的CdTe量子点对DA的氧化还原呈现明显的电催化作用,电催化过程为表面吸附控制过程。闭路吸附时间为60 s达到饱和,此电极可用于测定DA,响应迅速(1.5 s)。峰电流与DA浓度在4×10-4—5×10-5mol/L范围内呈线性关系,灵敏度高达0.061 9 A.L/mol,检测极限可达1.4×10-6mol/L。

In this paper, a CdTe quantum dot modified carbon paste electrode （CdTe/CPE） was prepared. The elec- trochemical behaviors of dopamine （DA） on CdTe/CPE were also studied systematically. The results show that the CdTe/CPE exhibits catalytic effect toward the oxidation of DA in phosphate buffer （pH 7.0）, and the electrocatalytic process is an adsorption controlled process. The response to dopamine on CdTe/CPE is very fast （ 1. 5 s）. The peak current has a good linear relationship to the DA concentration from 4 × 10^-4 to 5 ×10^-5 mol/L. The sensitivity is high as 0. 0619A · L/mol and the detection limit reaches 1.4 × 10^ -6 mol/L. This electrode can be used for electrochemical determination of DA.