线性扫描伏安法测定腌菜中亚硝酸盐含量

摘要

构建了二氧化钛纳米管和纳米金复合修饰玻碳电极(TiNTs-AuNPs/GCE),研究了亚硝酸盐在该修饰电极上的伏安分析特性,据此建立了测定腌菜中亚硝酸盐含量的线性扫描伏安法.优化了分析介质以及修饰剂用量等测定条件.在优化实验条件下,亚硝酸盐的氧化峰电流与其浓度在3.0×10-7～2.0×10-4mol/L区间内线性关系良好,检出限为1.0×10-7mol/L (S/N=3 ).运用该法测定了腌菜中的亚硝酸盐含量,平均回收率在96.8%～104.3%之间,结果令人满意.%A titania nanotubes (TiNTs)and gold nanoparticles (AuNPs)modified glassy carbon electrode (TiNTs-AuNPs/GCE)is fabricated.The voltammetric characteristics of nitrite at the modified electrode is investigated and a simple linear sweep voltammetry (LSV)method is developed for the determination of nitrite content in pickled vegetables.The experimental parameters such as analytical electrolyte, the amount of modifier are optimized.Under the optimized experimental conditions,the oxidation peak current varies linearly with the concentration of nitrite in the range of 3.0×10-7～2.0×10-4mol/L with a detection limit of 1.0×10-7mol/L (S/N=3).The proposed method has been applied for the determination of nitrite content in pickled vegetables with satisfactory results,the average recoveries are between 96.8% and 104.3%.