基于荧光探针的汞离子检测方法研究

Detection of Hg2+ based on fluorescent probe

中文关键词:  罗丹明B  荧光探针  脱硫反应  Hg(Ⅱ)

英文关键词:rhodamine B  fluorescent probe  desulfurization  Hg(Ⅱ)

中文摘要:

      目的 建立基于荧光探针的汞离子快速检测方法。方法 基于汞离子促进硫羰基脱硫的不可逆反应,设计合成了含有双硫羰基的荧光探针HgP1。通过紫外-可见光谱法和荧光光谱法研究了探针HgP1在甲醇水溶液中对金属离子的识别特性, 并探讨了其识别机制。结果 探针HgP1对Hg2+具有高效专一的选择性, 具有较强的抗金属阳离子和阴离子干扰能力, 并能通过溶液颜色变化实现对汞离子的裸眼识别。Hg2+浓度在0.01~0.1 μmol/L范围内与该探针溶液荧光发射强度值间呈良好的线性关系(R2=0.988), 该方法对汞离子的最低检测限为0.256 μg/kg。结论 HgP1探针对汞离子具有高效专一的选择性, 其最低检测限满足国家标准对食品中汞离子的限量要求, 具备较强的实际应用价值。

英文摘要:

      Objective To establish a method for rapid detection of Hg2+ based on fluorescent probe. Methods Based on the irreversible desulfurization of thiocarbonyl promoted by mercury ions, a new bis(rhodamine)-based chemodosimeter (HgP1) was synthesized and characterized. Ultraviolet and fluorescence spectrum analysis methods were selected to screen out high sensitive and selective fluorescent probes for Hg2+, and then the recognition mechanism was discussed. Results The probe HgP1 exhibited high selectivity and excellent sensitivity in both absorbance and fluorescence detection of Hg2+, and exhibited highly selective binding with Hg2+ over other metal ions and various coexistent anions. The significant changes in the fluorescence color could be used for naked-eye detection. Hg2+ had a good linear relationship in the range of 0.01~0.1 μmol/L between the fluorescence intensity and the concentration, with the correlation coefficient of 0.988. And the limit of detection of probe HgP1 for the determination of Hg2+ was 0.256 μg/kg. Conclusion The probe HgP1 exhibits highly selective binding with Hg2+ over other metal ions, and the minimum detection limit of Hg2+ can meet the requirements of the national standards, which has an actual application value.