对催化分光光度法测定茶叶中痕量铁的探究  

Exploration on Using Catalyze Spectrophotometry to Measure the Trace Iron in Tea Leaves

作　　者：吴美霞[1] 黄丽[1] 王兴培[1] 夏珊[1] 

机构地区：[1]自贡市轻工业设计研究院有限责任公司,四川自贡643000

出　　处：《中国井矿盐》2016年第2期43-46,共4页China Well and Rock Salt

摘　　要：甲基绿是一种碱性染料。在弱酸性介质中,铁（Ⅲ）可以催化过氧化氢将甲基绿氧化褪色。本文以此指示反应,研究了在弱酸性介质中微量铁催化H2O2氧化甲基绿褪色的反应,建立了一种催化动力学分光光度法测定茶叶中微量铁的方法,确定了最佳实验条件。实验结果表明,在酸性条件下,铁（Ⅲ）可以催化过氧化氢将其氧化褪色。最大吸收波长为630nm,线性回归方程为y=1.8457x＋0.0199,线性相关系数为r2=0.9993。在0.00-0.25ug/mL范围以内符合比尔定律。该方法用于茶叶中痕量铁的测定,灵敏度高,选择性好。Methyl green is a kind of basic dye. In the medium of faintly acid, Fe（Ⅲ）can catalyze hydrogen peroxide and make the methyl green oxidation fading. This paper according to this reaction, researches the reaction of trace iron catalyzes H2O2 and then oxidizes methyl green to fade in the medium of faintly acid. And then builds one way to catalyze dynamical spectrophotometry to measure the trace iron in the tea leaves, and confirms the best experimental conditions. The experiments＇ results show that Fe（Ⅲ）can catalyze hydrogen peroxide and make it oxidation fading under the acidic condition. The maximum absorption wavelength is 630 nm, and the equation of linear regression is y=1.8457x＋0.0199; the linearly dependent coefficient is r2=0.9993; match the Beer＇s Law between the range of 0.00-0.25ug/mL. Applying this method in measuring the trace iron in the tea leaves, the sensitivity is high and the selectivity is good.

关 键 词：甲基绿 铁 催化动力学 分光光度法 

分 类 号：TS37[轻工技术与工程]