化学试剂乙酸铵的硝酸盐测定方法改进

Improvement of Determination of Nitrate in Chemical Reagent Ammonium Acetate

在GB/T 1292-2008化学试剂乙酸铵标准中,用马钱子碱比色法测定硝酸盐,但马钱子碱是剧毒品,在购买、使用和保管上有诸多限制。本文以靛蓝二磺酸钠(靛蓝胭脂红)分光光度法代替马钱子碱比色法测定化学试剂乙酸铵中的硝酸盐,最佳线性范围0~50μg(以NO_3计),相对标准偏差优于10%,平均加标回收率可达95%,且两种方法检测结果一致。靛蓝二磺酸钠(靛蓝胭脂红)分光光度法避免使用剧毒品,方法准确、简便且实用。

In the standard of chemical reagent ammonium acetate GB/T 1292-2008, nitrate was determined by brucine colorimetry. But brucine is highly toxic chemical, and there are many restrictions in the purchase, use and storage. Instead of brucine colorimetry, indigotindisulfonate sodium （indigo carmine） speetrophotometry was used for the determination of nitrate in chemical reagent ammonium acetate. The best linear range was obeyed in the range of 0 - 50 μg （as NOa） , the relative standard deviation was less than 10% , the average recovery was 95%. The results of the two methods were consistent. Indigotindisulfonate sodium （indigo carmine） spectrophotometry was proved to be accurate, simple and practical, and avoided the use of highly toxic substances.