流动注射化学发光法测定茶叶和蔬菜中亚硝酸根

FI-Chemiluminescence Determination of Nitrite in Tea and Vegetables

利用亚硝酸根对鲁米诺-溴酸钾体系的化学发光具有显著增强作用,结合流动注射技术,建立了一种简单、快速测定亚硝酸根方法。方法的线性范围为4.0×10^-3-4.0 mg·L^-1;检出限为2.0×10^-3mg·L^-1（3σ）;分别对0.01 mg·L^-1和0.40 mg·L^-1的亚硝酸根进行了平行测定（n=11）,其相对标准偏差分别为1.3%与1.5%。应用于茶叶、蔬菜中的亚硝酸根的测定,回收率为92.3%-108.0%。

Based on the enhancement effect of NO2^- on the chemiluminescence （CL） reaction system of luminol and potassium bromate, and applying the flow injection （FI） technique, a new FI-CL method for determination of NO2^- was proposed. Linearity was kept in the range of 4. 0×10^-3 -4. 0 mg·L^-1 of NO2^-, with a detection limit （3σ） of 2×10^-3mg·L^-1. Precision was tested at the NO2^- concentration levels of 0. 01 mg·L^-1 and 0. 40 mg·L^-1, the values of RSD＇s （n=11） obtained were 1.3% and 1.5% respectively. In the application of the proposed method to the determination of NO2^- in tea and vegetable samples, recoveries in the range of 92. 3% - 108. 0% were obtained.