双波长分光光度法测定食盐中硒含量  

Dual-wavelength spectrophotometric determination of selenium content in salt

作　　者：李人宇[1,2] 李咏梅[2,3] 吴俊杰[1] 熊情[1] 

机构地区：[1]连云港师范高等专科学校,江苏连云港222006 [2]淮海工学院江苏省海洋资源开发研究院,江苏连云港222005 [3]淮海工学院化学工程学院,江苏连云港222005

出　　处：《中国调味品》2010年第9期83-86,共4页China Condiment

基　　金：连云港市科技项目(SH0816);江苏省海洋资源开发研究院科技开放基金项目(JSIMR09C08);淮海工学院自然科学基金项目(Z2008019)资助

摘　　要：在聚乙烯醇（PVA）存在下,在pH10.4的NaHCO3-NaOH缓冲溶液中,硒（IV）与1-（2-吡啶偶氮）-2-萘酚（PAN）、溴化十六烷基吡啶（CPB）反应形成稳定的络合物,该络合物在410 nm处有正吸收峰,529 nm处有负吸收峰,据此建立了双波长光度法测定痕量硒（IV）的新方法。硒（IV）浓度在0~0.12μg/mL内符合比尔定律,方法检出限为1.82μg/L,表观摩尔吸光系数ε为3.38×105L.mol-1.cm-1。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0.82%~1.16%（n=5）,加标回收率为99.7%~101.0%。A new dual-wavelength spectrophotometric method for determination of selenium content was developed.It was based on the reaction of Se（IV）,1-（2-pyridylazo）-2-naphthol（PAN） and cetylpyridinium bromide（CPB） to form a stable complex in NaHCO3-NaOH buffer solution at pH 10.4 in presence of PVA.The complex exhibited a positive absorption peak at 410 nm and a negative absorption peak at 529 nm.Beer＇s law was obeyed in the concentration range of 0～0.12 μg/mL for selenium.The limit of detection was 1.82 μg/L.The apparent molar absorptivity was found to be 3.38 × 105 L·mol-1·cm-1.The method was applied to determine selenium content in salt fortified with selenium and health balance salt samples with relative standard deviation of 0.82 %～1.16 % and standard addition recovery of 99.7%～101.0 %,the results were in good agreement with those provided by fluorometric method.

关 键 词：双波长分光光度法 硒 1-(2-吡啶偶氮)-2-萘酚(PAN) 溴化十六烷基吡啶(CPB) 

分 类 号：TS364[轻工技术与工程]