白杨素增敏荧光法测定粮食样品中的痕量锰  

Determination of trace manganese in grain based on fluorescence enhancement with chrysin

作　　者：姚俊丽[1] 滕秀兰[1] 马永钧[1] 周敏[1] 潘玉莹[1] 杨海青[1] 

机构地区：[1]西北师范大学化学化工学院甘肃省高分子材料重点实验室,甘肃兰州730070

出　　处：《化学试剂》2009年第8期609-613,618,共6页Chemical Reagents

基　　金：甘肃省自然科学中青年基金资助项目(2007GS-03596)

摘　　要：提出了一种用新型多核三元配合物荧光增敏技术测定粮食样品中痕量锰(Ⅱ)的新方法。在含一定量甲醇和表面活性剂Tween-80,pH4.5的醋酸-醋酸钠缓冲溶液中,白杨素、铬(Ⅲ)和锰(Ⅱ)之间能形成物质的量比为4∶1∶2且具有强荧光发射特性的新型多核三元混配配合物,其最大激发波长和发射波长分别为225和342nm。在优化的测定条件下,锰(Ⅱ)含量在0.396～16.2μg/L范围内与配合物的荧光发射强度F之间呈良好的线性关系,线性回归方程为:F=298+40.4c(μg/L),相关系数r=0.9990,方法的检出限为0.352μg/L(3σ)。该方法具有灵敏度高、选择性好、操作简单、快速的优点,可用于粮食中痕量锰(Ⅱ)的测定,实样回收率为100%～104%。A new enhancement fluorimetry for determination of trace manganese（Ⅱ）in grain samples was developed.In a buffer solution of HAc-NaAc with a pH value of 4.5,chrysin reacted with Cr（Ⅲ）and Mn（Ⅱ）at a molar ratio of 4∶1∶2,to form a highly fluorescent active polynuclear ternary complex in the presence of a definite amount of methanol and surfactant Tween-80.The maximum excitation and emission wavelengths of the ternary complex were 225 nm and 342 nm,respectively.Under the optimum conditions,the fluorescence intensity at 342 nm increased linearly with the concentration of Mn（Ⅱ）in the range of 0.396 μg/L～16.2 μg/L,with a linear regression equation of F=298＋40.4c（μg/L）and a correlation coefficient of r=0.999 0.The detection limit of this analytical method was 0.352 μg/L（3σ）.The method had the advantages of simplicity,high sensitivity and fast speed,and had been successfully applied to the determination of trace Mn（Ⅱ）in grain samples with satisfactory results.The real sample recovery ranged from100% to 104%.

关 键 词：锰(Ⅱ) 铬(Ⅲ) 白杨素 黄酮 荧光分析法 三元配合物 

分 类 号：O656.31[理学—分析化学]