银离子存在下变色酸的催化还原和检测应用

Reduction and Detective Application of Chromotropic Acid in the Presence of Ag^+

以变色酸为稳定剂和探针,在最佳反应条件和Ag^+存在下,NaBH_4能够有效还原变色酸,伴随体系在440nm发射波长处有明显的荧光增强现象,随着Ag^+浓度的增加荧光呈现规律性的变化,即荧光增强值(ΔI)与Ag^+浓度之间(Ag^+浓度为5.0×10^(-8)~1.0×10^(-6) mol/L)有良好的线性关系(ΔI_F=7.78×10~8c-33.41,相关系数r=0.996 4)。基于此建立了测定银离子的方法。该方法操作简单、可靠、灵敏度高,在最佳条件下检测Ag^+的最低浓度可达5.0×10^(-8) mol/L。

Chromotropic acid can be reduced by NaBH_4 in the presence of Ag~＋ and increase the intensity of fluorescence at 440 nm.Under optimal conditions the fluorescence enhancement value（ΔIF）has a linear relationship with the concentration of Ag~＋,which follows a linear equation of ΔIF=7.78×10~8 c-33.41 with a correlation coefficient of r=0.996 4 in the range of 5.0×10^-8 to 1.0×10^-6 mol/L.Based on this,a simple,reliable and sensilive method for detection of Ag~＋ by fluorescence analysis is established.The lowest concentration for Ag~＋ detection achieved is 5.0×10^-8 mol/L under the optimal conditions.