摘要
根据稀磷酸介质中亚硝酸根对溴酸钾氧化结晶紫的氧化还原反应具有明显催化作用的特性,应用结晶紫电极跟踪反应液中结晶紫的浓度变化,建立了一种新的测定亚硝酸根的催化电位法。方法在室温下进行操作方便,具有较高的灵敏度和选择性。线性范围为0.02～6.0μg/25ml,方法检出限为3.9×10^(-9)g·ml^(-1)NO_2^-。方法应用于测定几种环境水样中亚硝酸根含量,结果满意。方法的RSD<4.8％,样品加标平均回收率为96.6％。测定值与文献法值对照基本一致。
In this paper a new catalytic potentiometric method for the determination of nitrite was developed , based on the ability of nitrite to catalyze the redox reaction of crystal violet with potassium hromate in a phosphoric acid medium. Crystal violet ion selective electrode was used to indicate the change of the concentration of crystal violet in the reaction solution. This method can be operated conveniently at ambient temperature. It showed a high sensitivity and good selectivity and had a linear relation ship within the range of 0. 02~ 6. 0μg/25ml of NO^-_2r and a detection limit of 3.9×10^(-9)g ?ml^(-1) of NO^-_2, This method has been used to determine nitrite in environmental water samples and in urine sample with satisfactory resules. The relative standard deviration (RSD) less than 4.8% and the average recovery found by the standard addition method was 96.6%.
出处
《理化检验（化学分册）》
CAS
CSCD
北大核心
1999年第5期207-210,共4页
Physical Testing and Chemical Analysis(Part B:Chemical Analysis)
关键词
催化电位法
测定
亚硝酸根
尿样
水样
Catalytic potentiometry, Crystal violet selective electrode, Nitrite, Water and urine sample
