纳米金/β-环糊精复合修饰碳糊电极测定亚硝酸盐

Gold Nanoparticles and β-Cyclodextrin Modified Carbon Paste Electrode for the Determination of Nitrite

本文研究了亚硝酸盐(NO_2^-)在纳米金和β-环糊精复合修饰碳糊电极(AuNPs-β-CD/CPE)上的电化学行为。实验结果表明,与裸CPE相比,AuNPs-β-CD/CPE对NO_2^-的电化学氧化有显著的促进作用,其氧化峰电流显著增加。同时用循环伏安法(CV)、计时电流法(CA)测定了NO_2^-在AuNPs-β-CD/CPE上的电极反应动力学参数,用线性扫描伏安法(LSV)法测得NO_2^-氧化峰电流与其浓度在6.0×10-6~8.0×10-3 mol·L-1范围内呈良好的线性关系,检出限(S/N=3)为5.7×10-7 mol·L-1。将该传感器应用于水样的检测,相对标准偏差在0.15%~1.40%之间,回收率达99.3%~104.0%,检测结果符合定量测定要求。

In this paper,the electrochemical behavior of nitrite（NO2^-）at gold nanoparticles andβ-cyclodextrin modified carbon paste electrode（AuNPs-β-CD/CPE）was studied.The experimental results indicated that compared with CPE,AuNPs-β-CD/CPE showed better electrochemical performance for NO2^-oxidation.Cyclic voltammetry and chronoamperometry were used to determine the reaction kinetics parameters of NO2^-on the AuNPs-β-CD/CPE electrode.The relationship between NO2^-oxidation peak current and its concentration was evaluated by linear sweep voltammetry.The oxidation peak current of NO2^-had a good linear relationship with its concentration in the range of 6.0×10^-6-8.0×10^-3 mol·L^-1,and the detection limit（S/N=3）was 5.7×10^-7 mol·L^-1.The proposed method was successfully applied in the determination of water samples,with the relative standard deviations of 0.15%-1.40%and recoveries of 99.3%-104.0%,which meets the requirement of quantitative measurement.