荧光银纳米团簇的生物合成及其在痕量六价铬检测中的应用

Synthesis of fluorescent silver nanoclusters for trace Cr (Ⅵ) detection

摘要:

[目的] 利用季也蒙毕赤酵母ZJC-1合成银纳米团簇并用于痕量Cr （VI）的检测。[方法] 使用经耐银驯化的季也蒙毕赤酵母ZJC-1生物合成荧光银纳米团簇，并对其结构和荧光性能进行了表征，探究Cr （VI）对银纳米团簇荧光的选择性猝灭作用，建立了银纳米团簇荧光强度与Cr （VI）浓度的线性关系。同时还考察了体系pH和其他金属离子对Cr （VI）检测的影响。[结果] Cr （VI）浓度在一定的范围内（1-80 μmol/L）与银纳米团簇荧光强度（F₀-F）/F₀有着良好的线性关系（R²=0.9821），线性方程为（F₀-F）/F₀=0.0054×C_{cr （Ⅵ）}+0.1876，检测限为184 nmol/L （信噪比为3）。利用该方法检测实际水样（松花江、马家沟河）中的Cr （VI），回收率介于97.73%-102.88%之间。[结论] 以季也蒙毕赤酵母ZJC-1为还原剂和稳定剂，制备了具有较好荧光性能的水溶性银纳米团簇，基于Cr （VI）对银纳米团簇荧光的选择性猝灭作用，建立了一种快速且灵敏检测痕量Cr （VI）的新方法，并成功地应用于松花江、马家沟河水样中Cr （VI）的测定，在分析检测领域中具有良好的应用前景。

关键词:银纳米团簇;生物合成;荧光猝灭;Cr (VI)

Abstract:

[Objective] Silver nanoclusters were prepared using Pichia guilliermondii ZJC-1 for the detection of trace Cr(VI). [Methods] Fluorescent silver nanoclusters were synthesized using Pichia guilliermondii ZJC-1 that was acclimated to silver. The structures and fluorescence properties of silver nanoclusters were characterized. Then we explored the selective quenching effect of Cr(VI) on the silver nanoclusters fluorescence. We also established a linear relationship between silver nanoclusters fluorescence intensity and the concentration of Cr(VI). The effect of pH and other metal ions on the detection of Cr(VI) was also examined. [Results] There was a good linear relationship between Cr(VI) and the fluorescence intensity of silver nanoclusters (R²=0.9821). The detection limit was 184 μmol/L and the signal to noise ratio (SNR) was 3. Using this method to detect Cr(VI) in actual water samples (Songhua River, Majiagou River) the recovery rate was between 97.73% and 102.88%. [Conclusion] Silver nanoclusters with good fluorescence properties can detect trace concentrations of Cr(VI) simply and rapidly.

Key words:silver nanoclusters;biosynthesis;fluorescence quenching;Cr(VI)