食品科学 ›› 2004, Vol. 25 ›› Issue (7): 145-147.

• 分析检测 • 上一篇    下一篇

氧弹燃烧—灰化分光光度法测定食品中的磷和砷

 粟智   

  1. 新疆师范大学生命与环境科学学院
  • 出版日期:2004-07-15 发布日期:2011-10-24

Determination of Phosphorus and Arsenic in Food by the Oxygen Bomb Ashing Combustion and Spectrophotometry

 SU  Zhi   

  • Online:2004-07-15 Published:2011-10-24

摘要: 在高纯高压氧的环境中,对样品燃烧灰化,使有机物中的磷转变为磷的氧化物,以碱液吸收生成相应的可溶性磷酸盐和亚磷酸盐,经HNO3酸化使其全部转化为正磷酸,加Na2S2O3还原掩蔽砷后,加钼酸铵,硝酸铋,抗坏血酸呈磷铋钼蓝,测其吸光度,测定出磷的含量。吸收液用HNO3酸化,并通过KMnO4氧化后,在酸性介质中As5+可与钼酸铵、硝酸铋生成砷铋钼杂多酸,用抗坏血酸还原为砷铋钼蓝,测定其吸光度求得砷量。经回收率实验测试,磷的回收率为96.8%~103%,砷的回收率为96.3%~100%。该方法可直接用于食品中磷和砷的测定。

关键词: 氧弹, 燃烧, 灰化, 分光光度法, 食品, 磷,

Abstract: The paper introduced a simple and rapid method of determining the phosphorus and arsenic in food. At first thesample was combusted by the technology of oxygen bomb ashing combustion in high pressure and pure oxygen. Then, the ashingproducts were absorbed by the thick and strong base NaOH. Under the acid condition, the Arsenic concentration was determinedby As-Bi-Mo -blue spectrophotometry method after the As3+ was transferred into As5+ oxidized by the KMnO4 and thephosphorus could be analyzed by As-Bi-Mo -blue spectrophotometry method after the phosphorus in food was transformedto the phosphoric anhydride. These samples such as powder shrimp skin, flour and tea were analyzed by the method. The resultsshowed that the method was simple, fast and highly pure. The percent recovery of phosphorus was 96.8%~103% and arsenic96.3%~103%. The results showed that the method was practical and satisfactory and could be used in assaying the quantityof phosphorus and arsenic in food directly.

Key words: oxygen bomb, combustion, ashing, spectrophotometric method, food, phosphorus, arsenic