海藻酸钠-纳米金复合物荧光猝灭法测定纺织品中的铬(Ⅵ)  

Determination of Chromium(Ⅵ) in Textiles Based on Fluorescence Quenching of Nanogold Clusters

作　　者：李云[1,2] 李刚[2] 雷克林[1] 李明[2] 刘慧宏[2] 

机构地区：[1]湖北文理学院化学工程与食品科学学院,襄阳441053 [2]武汉纺织大学化学与化工学院,分析测试中心,武汉430200

出　　处：《分析化学》2016年第5期773-778,共6页Chinese Journal of Analytical Chemistry

基　　金：国家自然科学基金(No.51203125);低维光电材料与器件湖北省重点实验室开放基金(湖北文理学院13XKL01003)资助项目~~

摘　　要：生态纺织品中铬(Ⅵ)含量有严格的限制。本实验利用海藻酸钠一步法成功合成了纳米金溶胶,并对其荧光特性进行了研究。结果表明,海藻酸钠-纳米金复合物(Au NPs-SA)在激发波长λ_(ex)=330 nm处表现出最强荧光特性,在该激发波长下,最大发射波长λ_(ex)=415 nm。铬(Ⅵ)对海藻酸钠-纳米金复合物的荧光有猝灭效应,纳米金荧光强度随铬(Ⅵ)浓度的增加而减弱,利用其荧光猝灭特性建立了铬(Ⅵ)定量分析方法。调节AuNPsSA溶液至pH 7.0,加入Cr(Ⅵ),反应40 min后,测定荧光强度变化。铬(Ⅵ)浓度在1.0×10^(-8)~9.0×10^(-8)mol/L范围内与F/F_0有较好的线性关系(R=0.9919),方法的检出限(S/N=3)为5.0×10^(-9)mol/L。本方法用于纺织品中苎麻与涤纶的痕量铬(Ⅵ)的检测,所得结果与国家标准方法(GB/T 17593.3-2006)没有显著性差异。Chromium（VI） is one of the forbidden heavy metals in the ecological textiles. It is vitally important to develop methods for the sensitive and selective detection of Cr（VI） in textile samples. In this work, gold nano- particles-sodium alginate clusters （AuNPs-SA） was prepared with sodium alginate in one-step synthesis route and its fluorescent property was investigated. The strongest fluorescence intensity of AuNPs-SA clusters located at the max emission wavelength λem =415 nm under the excitation wavelength of λex =360 nm. A fluorimetrie method was developed based on the fluorescent AuNPs-SA nanoeomposites selectively quenched in the presence of Cr（VI）. The possible quenching mechanism was discussed on the basis of the interaction of positive AuNPs-SA with negative Cr （VI）. Under the optimized experimental conditions, The ratiometrie fluorescence was linearly proportional to the concentration of Cr（VI） ranging from 1.0× 104 mol/L to 9.0× 104 mol/L. The limit of determination （LOD） was estimated at 5.0 × 10-9 mol/L based on the regression calculations. This method was used for the determination of chromium （Ⅵ） in textile samples, and the obtained result had no significant difference compare to the results based on the National Standard of the People＇s Republic of China （ GB/T 17593.3-2006） .

关 键 词：海藻酸钠 纳米金 荧光猝灭 铬(Ⅵ) 

分 类 号：O657.3[理学—分析化学] TS107[理学—化学]