阻抑荧光光度法测定痕量锡  

Determination of Trace Tin by Inhibitory Fluorescence Spectrophotometry

作　　者：张丽娜[1] 李波[1] 于京华[1] 魏琴[1] 

机构地区：[1]济南大学化学化工学院,济南250022

出　　处：《应用化学》2008年第12期1417-1420,共4页Chinese Journal of Applied Chemistry

基　　金：国家十一五支撑计划子课题(2006BAJ03A09-06);山东自然科学基金(Y2007B07);山东省重点学科基金(XTD0705)资助项目

摘　　要：在pH=5．0的邻苯二甲酸氢钾．氢氧化钠缓冲溶液中，痕量锡（Ⅳ）强烈地催化高碘酸钾氧化3-（3′-氯苯基）-5-（2′-胂酸基偶氮）若丹宁的反应，引起体系荧光强度的明显猝灭，其最大荧光激发和发射波长为308nm／410nm。据此建立催化荧光猝灭法测定痕量锡（Ⅳ）的新方法，计算反应的表观活化能Ea=51．20kJ／mol，反应速率常数k=1．23×10^-9／s。该方法线性范围为0～0．01×10^-6g／mL，检出限为1．65×10^-9／mL。经过巯基葡聚糖凝胶（SDG）分离富集可以显著提高测定的选择性和灵敏度。用于食品及环境水样中痕量锡的测定，结果满意。A new method for the determination of trace tin has been established. The method is based on the catalytic effect of Sn （ Ⅳ ） on the oxidation of 3-（3′-chlorophenyl） -5-（2′-aresenoxylphenylazo） rhodanine by potassium periodate in a buffer solution of potassium hydrogen phthalate-sodium hydroxide at pH = 5.0, where the apparent active energy and reaction rate constant are calculated to be 51.20 kJ/mol and 1.23 × 10^-2/s. The excitation and emission wave lengths are 308 nm/410 nm, the linear range is 0 -0.01 × 10^ -6 g/mL, the detection limit is 1.65 × 10^-9 g/mL. The method has been used to determine Sn（Ⅳ） in food and environmental water with satisfactory results after separation and enrichment on sulphydryl dextran gel, which can enhance the selectivity of the method significantly.

关 键 词：催化荧光法 锡 若丹宁 巯基葡萄糖凝胶 

分 类 号：O657.3[理学—分析化学]