芳香族氨基酸作探针荧光猝灭法测定痕量抗坏血酸  

Determination of Trace Ascorbic Acid by Fluorescence Quenching Method with Aromatic Amino Acids as Probes

作　　者：董存智[1] 桂王艳[1] 吴雯辉[1] 

机构地区：[1]淮北师范大学化学与材料科学学院

出　　处：《光谱实验室》2013年第2期645-648,共4页Chinese Journal of Spectroscopy Laboratory

摘　　要：在pH 7.0的B-R缓冲溶液中,基于抗坏血酸对色氨酸、酪氨酸、苯丙氨酸等芳香族氨基酸荧光的猝灭作用,建立了荧光猝灭法测定抗坏血酸的新方法。在最适宜条件下,方法的线性范围和检出限分别为:0.1—20mg/L、0.045mg/L(色氨酸体系);0.05—15mg/L、0.032mg/L(酪氨酸体系);0.01—5mg/L、0.0038mg/L(苯丙氨酸体系)。方法已应用于实际样品的测定并对反应机理进行了探讨。In pH 7. 0 Britton-Robinson buffer medium, ascorbic acid can lead to fluorescence quenching of some aromatic amino acids such as tryptophan, tyrosine and phenylalanine by reacting with them, based on which, a new method for the determination of trace ascorbic acid was developed by fluorescence quenching method. Under the optimal conditions, the linear ranges of ascorbic acid were 0.1-20mg/L for tryptophan system, 0.05-15mg/L for tyrosine system and 0.01-5mg/L for phenylalanine system. The detection limits of ascorbic acid were 0. 045mg/L for tryptophan system, 0. 032mg/L for tyrosine system and 0. 0038mg/L for phenylalanine system. The method was applied to the determination of ascorbic acid in vitamin C tablets with satisfactory result, and the reaction mechanism was preliminary studied.

关 键 词：抗坏血酸 荧光猝灭 色氨酸 酪氨酸 苯丙氨酸 

分 类 号：O657.32[理学—分析化学]