等摩尔吸收点二甲酚橙光度法测定紫菜中钙和镁  

Determination of calcium and magnesium of laver by xylenol orange isosbestic point spectrophotometry

作　　者：陈晓红[1] 达古拉[1] 徐玲[1] 

机构地区：[1]内蒙古民族大学化学化工学院,通辽028043

出　　处：《食品科技》2014年第9期300-302,共3页Food Science and Technology

基　　金：内蒙古自然科学基金项目(2011BS0203);内蒙古自治区高等学校科学研究资助项目(NJZY12121)

摘　　要：在pH=10.5的NH3-NH4Cl缓冲溶液中,Ca^2＋、Mg2＋均与二甲酚橙形成紫色配合物。研究以二甲酚橙为显色剂,利用等摩尔吸收点光度法测定Ca^2＋、Mg^2＋含量的方法。实验表明,等吸收点测定波长为λ=584 nm,最佳实验条件下,Ca^2＋、Mg^2＋总量在0～6.0×10^-5 mol/L范围内符合Lambert-Bill定律,检出限为7.2×10^-6 mol/L。该法用于紫菜中钙镁含量的测定,方法的相对标准偏差为3.6%,加标回收率为96.0%。In pH=10.5 NH3-NH4Cl buffer solution, calcium, magnesium and xylenol orange formation coloured coordination complex. The article has researched determination of calcium, magnesium by xylenol orange isosbestic point spectrophotometry. The results showed that absorption wavelength A=584 nm. It has been found that Ca^2＋, Mg^2＋ content according with Lambert-Bill laws from 0～6.0×10^-5 mol/L.The minimum concentration detected is 7.2×10^-6 mol/L. The method is applied determination of laver, the relative standard deviation was 3.6%, recovery is 96.0%.

关 键 词：二甲酚橙 等吸收点光度法 CA^2+ 、Mg^2+ 紫菜 

分 类 号：TS254.7[轻工技术与工程—水产品加工及贮藏工程]