离子缔合体系分光光度法测定食盐中微量硒  

Spectrophotometric Determination of Trace Selenium in Edible Salt with Ion-association System

作　　者：李人宇[1] 陶明涛[1] 李咏梅[2] 周家宏[3] 李廷友[1] 

机构地区：[1]连云港师范高等专科学校,江苏连云港222006 [2]淮海工学院化学工程系,江苏连云港222005 [3]南京师范大学分析测试中心,江苏南京210097

出　　处：《盐业与化工》2009年第5期29-32,共4页Jounral of Salt and Chemical Industry

基　　金：国家自然科学基金项目(20603018);连云港市科技项目(CN0646;SH0816);淮海工学院自然科学基金项目资助

摘　　要：基于在0.02 mol/L硫酸中,硒(IV)与过量的I-反应生成I3-,I3-进一步与吖啶橙(AO)反应生成1∶1离子缔合物,体系吸光度明显增强,建立了分光光度法测定痕量硒(IV)的新方法。试验了酸度、试剂用量、表面活性剂、温度和时间的影响,确定了最佳测定条件。最大吸收峰位于491 nm。线性范围为0μg/L^56μg/L。检出限为1.07μg/L。大量IO3-干扰可用盐酸羟胺消除。方法用于硒强化营养盐和健康平衡盐中硒含量的测定,结果与荧光法测定值一致,相对标准偏差为0.61%~0.70%(n=5),加标回收率为100.4%~100.8%。A new method for determination of trace Se （IV） by spectrophotometry was developed. The method was based on the reaction of Se （IV） with excess I- in 0.02 mol/L H2SO4 to produce 13 , and it further reacted with acridine orange （AO） to form an ion - association complex （ 1 ： 1 ）, resulting in great enhancement of absorbency with the maximum absorption peak at 491 nm. The optimal conditions of measurements of Se （IV） including acidity, reagents dosage, surfaetant, temperature and time were studied. Linear concentration range was between 0 μg/L and 56 Ixg/L. The detection limit was 1.07 μg/L. The interference of much IO3- could be eliminated by hydrazine hydrochloride. The method was applied to determine selenium content in salt fortified with selenium and health balance salt samples with relative standard deviation of 0.61% -0.70% and standard addition recovery of 100.4% - 100.8% , and the results were in good agreement with those provided by the fluorometric method.

关 键 词：分光光度法 硒 离子缔合物 碘化物 吖啶橙 

分 类 号：O657.32[理学—分析化学]