食品科学 ›› 2007, Vol. 28 ›› Issue (12): 390-392.

• 分析检测 • 上一篇    下一篇

DBM-偶氮胂分光光度法测定食品中的钙

 李景梅, 翟庆洲, 张勇   

  1. 长春理工大学纳米技术研究中心; 长春理工大学纳米技术研究中心 吉林长春130022; 吉林长春130022;
  • 出版日期:2007-12-15 发布日期:2011-11-22

Spectrophotometric Determination of Calcium in Foodstuffs with DBM-Arsenazo

 LI  Jing-Mei, DI  Qing-Zhou, ZHANG  Yong   

  1. Research Center for Nanotechnology, Changchun University of Science and Technology, Changchun 130022, China
  • Online:2007-12-15 Published:2011-11-22

摘要: 研究了DBM-偶氮胂(DBM-ASA)与Ca2+的显色反应最佳实验条件。在pH10.4NH3-NH4Cl缓冲介质中,Ca(Ⅱ)与DBM-ASA形成蓝色络合物,该络合物组成比为Ca(Ⅱ):(DBM-ASA)=1:2,最大吸收波长位于628nm处,表观摩尔吸光系数e628nm=3.92×104L/mol·cm,钙量在2~10μg/10ml范围内遵守比耳定律。工作曲线回归方程:A=0.0428C+0.148(C:μgCa2+/10ml),相关系数γ=0.9934。本法用于大米、面粉及土豆食物样品中钙的测定,分析结果与原子吸收光谱法相一致。本法六次测定相对标准偏差0.62%~1.03%,加标回收率为98.0%~100.5%。

关键词: 钙, 分光光度法, DBM-偶氮胂, 食品

Abstract: The optimum experimental conditions of the color reaction between DBM-arsenazo and calcium were studied. Calcium(Ⅱ) reacts with DBM-arsenazo to produce a blue complex with a molar ratio of 1:2(M:R) in NH3-NH4Cl buffer solution medium at pH 10.4. The maximum absorption wavelength of the complex locates at 628 nm. The apparent molar absorptivity of the method is e 628nm = 3.92 × 104 L/mol·cm. Beer’s law is obeyed over the range of 2 ~ 10 μg of calcium in 10 ml of solution. The method was used in the determination of calcium in rice, wheat flour and potato foodstuff samples and the obtained results are in excellent agreement with those obtained by atomic absorption spectrometry. The relative standard deviations of six replicate determinations are 0.62 % ~ 1.03 % and the recoveries of the standard addition are 98.0%~100.5%.

Key words: calcium, spectrophotometry, DBM-arsenazo, foodstuff