流动注射—化学发光法测定蔬菜中的微量亚硝酸盐研究

Determination of Trace Nitrite in the Vegetable by Coupling Chemiluminescence Analysis

利用鲁米诺—铁氰化钾—尿酸化学发光体系,在酸性介质中,亚硝酸盐氧化亚铁氰化钾为铁氰化钾,建立了间接测定微量亚硝酸盐的方法。讨论了酸度、反应物浓度、干扰离子等因素的影响,检出限达5.0×10-5mg/L,线性范围在0.001￣10mg/L,加标回收率在97.5%￣104%之间,RSD≤3.6%,该方法尤其适合于较低微量亚硝酸盐的测定,可用于各种蔬菜中微量亚硝酸盐的测定。

In acidic medium that NO2^- oxidize [Fe（CN）6]^4- to [Fe（CN）6]^3- and luminol--[Fe（CN）6]^3-uric acid chemiluminescence system was coupled together, thus a new method for the determination of trace nitrite was developed. The effect of factors, such as consistency of various substance of reaction, acidity, disturbing ions etc., on the analytical results were studied. The Detection Limit was 5.0×10^-2mg/L （3a）. The Linear Range was at 0.001-10 mg/L. The parallel determination was done 12 times and the relative standard deviation was no more than 3.6%. The recovery was at the range of 97.5 to 104.