食品科学

• 分析检测 • 上一篇    下一篇

氧化变色酸2B光度法测定料酒中的微量锰

沙 鸥,陈 丽,马卫兴   

  1. 1.淮海工学院化学工程学院,江苏 连云港 222005;
    2.江苏省海洋资源开发研究院分析测试中心,江苏 连云港 222001
  • 出版日期:2013-06-25 发布日期:2013-06-17

Spectrophotometric Determination of Manganese in Cooking Wine Samples by Oxidation of Chromotrope 2B

SHA Ou,CHEN Li,MA Wei-xing   

  1. 1. School of Chemical Engineering, Huaihai Institute of Technology, Lianyungang 222005, China;
    2. Analysis and Test Center, Jiangsu Marine Resources Development Research Institute, Lianyungang 222001, China
  • Online:2013-06-25 Published:2013-06-17

摘要:

建立测定料酒中微量锰的氧化变色酸2B光度法。用铋酸钠将酒中的低价锰离子全部氧化为Mn(Ⅶ),在硫酸介质中,室温条件下变色酸2B能被锰(Ⅶ)氧化而褪色,在515nm波长处褪色明显,在该波长处体系吸光度的减少值与溶液中Mn(Ⅶ)的质量浓度呈正比,Mn(Ⅶ)离子质量浓度在0.05~5.0μg/mL范围内符合朗伯比尔定律,表观摩尔吸光系数ε515nm=2.05×104L/(mol·cm)。将该法用于市售白酒、料酒中锰的测定,结果与电感耦合等离子原子发射光谱法的测定结果一致,加标回收率在98.5%~101.9%之间。

关键词: 锰, 光度法, 变色酸2B, 料酒

Abstract:

A new spectrophotometric method for determining manganese in cooking wine was established by oxidation of
chromotrope 2B. In the presence of sodium bismuthate, all low-valent Mn ions in samples were oxidized to form to Mn (Ⅶ), which
oxided chromotrope 2B at room temperature in sulfuric acid medium resulting in fading. The most considerable reduction in the
absorbance at 515 nm was observed, which was directly proportional to Mn (Ⅶ) concentration. The absorbance obeyed Beer’s law
in the Mn (Ⅶ) concentration range of 0.05 to 5.0 μg/mL with an apparent molar absorption coefficient of 2.05 × 104 L/(mol•cm).
The recovery of the developed method for spiked samples of commercial liquor and cooking wine ranged between 98.5% and
101.9%, and the results obtained were consistent with those reported with ICP-AES.

Key words: manganese, spectrophotometry, chromotrope 2B, wine