固相分光光度法测定食品中的痕量硒

摘要

为探索能高效且准确地检测出食品中痕量硒的测定方法,采用以邻苯二胺作为显色剂的固相分光光度法,直接以树脂相在pH=2的条件下,在最大吸收波长344 nm处测定食品中痕量硒.结果表明:硒含量在0～50 μg/L范围内符合比尔定律,其中,吸附时间为15 min,树脂用量0.2g;使用EDTA掩蔽了干扰离子.结论:对小麦、菠菜、奶粉、猪肉4种常用食品进行标准加入法测定硒回收率,以固相分光光度法比传统的溶液分光光度法更适于食品中痕量硒的测定.%In order to seek an efficient and accurate method to determine the trace amount of selenium, the resin-phase spectrophotometry using o-phenylenediamine as the chromogenic reagent was adopted to determine the absorbance values at pH 2. 0 and 344 nm. The results showed that the absorbance values had a good linear relationship at 0~50 μg/L of Se content. The optimal conditions were as follows: pH was 2, extraction time was 15 min,resin quantity was 0. 2 g and using EDTA as masking agent. By determining the selenium concentration of four kinds of food. It was concluded that the solid-phase spectrophotometry was better than traditional solution spectrophotometry method on the determination of trace amount of selenium in food.