色氨酸荧光猝灭法测定食品中碘离子含量  

Determination of Iodide Ions in the Foodstuff Based on the Fluorescence Quenching Effect of Tryptophan

作　　者：黄冬兰[1] 胡心蕊 胡毅青 林炜棋 Huang Donglan;Hu Xinrui;Hu Yiqing;Lin Weiqi(College of Chemistry and Civil Engineering,Shaoguan University,Shaoguan 512005,China)

机构地区：[1]韶关学院化学与土木工程学院,广东韶关512005

出　　处：《广东化工》2025年第1期148-150,共3页Guangdong Chemical Industry

基　　金：广东省高校重点平台和科研项目(2020KTSCX135);韶关市科技计划项目(200811094530440);韶关学院博士科研启动项目(40899000407);广东省大学生创新创业训练计划项目(Sycxcy2023183);韶关学院2022年校级质量工程建设项目([2022]34);韶关学院2023年校级课程思政建设项目(71)。

摘　　要：在pH=6的磷酸缓冲溶液(PBS)中,碘离子(I^(-))的存在对色氨酸的荧光强度有猝灭作用,基于此建立了一种荧光猝灭法测定食品中碘离子含量的分析方法。实验结果表明:最大激发波长为295 nm时,色氨酸在370 nm波长处有较强的荧光产生,且碘离子(I^(-))的存在量与其荧光猝灭程度之间存在定量的关系。色氨酸的荧光猝灭程度(F0/F)与碘离子(I^(-))物质的量浓度在3μmol/L~15μmol/L范围内呈良好的线性关系,线性拟合方程为F_(0)/F=0.1206[I^(-)]+1.2514,相关系数为R^(2)=0.9967,检出限为0.4087μmol/L,加标回收率为97.00%~103.00%。Iodide ions have a strong quenching effect on the fluorescence intensity of tryptophan in the phosphoric acid buffer solution(PBS,pH=6).On the basis of the phenomena,a novel fluorescence quenching method for the determination of iodine ions in foods was developed.The experiment results indicate that tryptophan has fluorescence at 370nm with an excitation wavelength of 295nm.Moreover,the results also show that there is a quantitative relationship between the amount of iodide ions and the amount of fluorescence quenching(F_(0)/F).There is a linear relationship between the amount of fluorescence quenching(F_(0)/F)and the amount of iodide ions when the concentration of iodide ions is in the range of 3μmol/L~15μmol/L.The equation of the linear relationship is F0/F=0.1206[I-]+1.2514(R^(2)=0.9967),the detection limit is 0.4087μmol/L.And the recovery of the added standard sample is 97.00%~103.00%.

关 键 词：色氨酸 荧光猝灭 碘离子 

分 类 号：TQ[化学工程]