紫外检测离子色谱法测定酱腌菜中的亚硝酸盐与硝酸盐

Determination of Nitrite and Nitrate in Pickled Vegetables by Ion Chromatography with Ultraviolet Detection

建立了紫外检测离子色谱法测定酱腌菜中的亚硝酸盐与硝酸盐的分析方法。样品经超声提取后，以1．8mmol／L Na2CO3＋1．7mmol／LNaHCO3为流动相，经Metrosep A Supp4-250阴离子交换色谱柱分离，于210nm处紫外检测。结果表明：此法NO2^-、NO3^-的检出限分别为1．0mg／kg和2．0mg／kg，实际样品的加标回收率分别为80．4％～82．1％和93．1％～96．5％，相对标准偏差≤10％。

A simple and accurate method for determination of nitrite and nitrate in pickled vegetables by ion chromatography with ultraviolet detection was established. The anions were extracted from the pickled vegetables by mixing and diluting the samples with water under ultrasonication at moderate temperature. An anion-exchange column Metrosep A Supp 4-250 and ultraviolet detector were employed. Considering a sample of 5.0 g, the minimum detection limits of nitrite and nitrate in this method were 1.0mg/kg and 2.0mg/kg （S/N=3）. The recovery of nitrite and nitrate were 80.4% - 82.1% and 93.1% - 96.5%, respectively, and the relative standard deviation of the method was less than 10%. These results demonstrated that the proposed method was simple, sensitive and reliable for the determination of nitrite and nitrate in pickled vegetables.