甲基紫褪色光度法测定矿泉水中溴酸根离子  

Determination of BrO_3^- by fading photometry of methyl violet

作　　者：刘爱国 杨胜圆[2] 沈天泱[2] 

机构地区：[1]湖南省株洲市劳动卫生职业病防治所,湖南株洲412000 [2]南华大学公共卫生学院,湖南衡阳421000

出　　处：《中国卫生检验杂志》2010年第3期533-535,共3页Chinese Journal of Health Laboratory Technology

摘　　要：目的:根据溴酸根离子对甲基紫氧化使其褪色的原理,建立一种褪色光度法测定矿泉水中溴酸根离子含量的方法。方法:在酸性条件下,以溴化钾为催化剂,溴酸根离子氧化甲基紫使其发生褪色反应,其褪色程度随溴酸根离子的增加而增加。在最大吸收波长及选定的最佳实验条件下,以蒸馏水为参比测定吸光度值A0、Ai,△A=A0-Ai,标准曲线法定量。结果:甲基紫最大吸收波长(λmax)为583.0 nm,溴酸根离子的浓度在0.3~4.0×10-3μg/L范围内与溶液吸光度差值(△A)呈良好的线性关系,线性回归方程△A=65.41C(μg/L)+0.003,相关系数0.997。回收率95.6%~103.1%。结论:本法测定溴酸根离子,方法简便,灵敏度较高,可用于对水中的溴酸根离子的定量测定。Objective：According to the oxidation of methyl violet with BrO-3,a new method was developed for the determination of BrO-3 in the mineral water by fading photometry.Methods：In acidic conditions,KBr as a catalyst,methyl violet was oxidized by BrO-3 and the fading reaction occurred,the extent of the fading increase along with the amount of BrO-3.In the maximum absorption wavelength and selected the optimum experimental conditions,with distilled water as reference,determine the absorbance A0 and Ai,△A=A0-Ai.Results：The maximum absorption wavelength（λmax） of methyl violet was 583.0 nm.When the concentration of BrO-3 in the range of 0.3~4.0×10-3 μg/L,solution absorbance difference（△A） had good linear relationship to it.The regression equation was △A=65.41C（μg/L）＋0.003,the correlation coefficient was 0.997.The recoveries were 95.6%~103.1%.Conclusion：This new method is simple and can be used to determine BrO-3 in water samples.

关 键 词：溴酸根离子 甲基紫 褪色光度法 矿泉水 吸光度值 褪色反应 最大吸收波长 光度法测定 催化剂 线性回归方程 

分 类 号：O657.32[理学—分析化学]