摘要
生物样品用艾斯卡熔剂分解,强酸性阳离子交换树脂静态吸附分离大量Na^+等阳离子后,采用Fe^3+-SCN^--NO2^-催化体系分光光度法测定痕量碘。通过正交实验确定了催化反应的最佳实验条件。方法检出限(6s)为0.13μg/g,方法精密度(RSD,n=12)为3.69%~8.28%。用国家一级生物标准物质进行验证,测定值与标准值相符。
A method for the determination of trace iodine in plants by catalytic spectrophotometry is developed. The samples are decomposed by Eschka flux, extracted by hot deionized water and Na^+ is separated from sample solution by static adsorption with strong-acid cation exchange resin. Trace iodine in samples is then determined by spectrophotometry in Fe^3+-SCN^--NO2^- catalytic system. The catalytic reaction condition is optimized by orthogonal experiments. The detection limit (6s) of the method for iodine is 0.13 μg/g with precision of 3.69%~8.28% RSD (n = 12). The method has been applied to the determination of trace iodine in National Standard Reference cabbage, spinach and milk powder samples and the results are in good agreement with certified values.
出处
《岩矿测试》
CAS
CSCD
2006年第4期327-330,共4页
Rock and Mineral Analysis
基金
国土资源部地质大调查项目(DKD9904017)
关键词
催化分光光度法
碘
生物样品
静态分离
正交实验
catalytic spectrophotometry
iodine
biological sample
static separation
orthogonal experiment