镉(Ⅱ)-邻菲罗啉-曙红Y体系的共振光散射光谱研究及应用

Resonance light scattering spectra invescigotion and application of Cd(Ⅱ)-phen-EY system

在pH=4.5的HAc-NaAc介质中,Cd2+,phen及EY三者能通过静电引力和疏水作用力生成三元离子缔合物[Cd(phen)3]EY,其共振瑞利散射和共振非线性散射显著增强,最大的光谱散射波长分别位于RRS(375nm),SOS(732nm)及FDS(372nm)处.其散射增强程度(ΔI)与Cd2+浓度在一定范围内呈良好的线性关系,检出限分别为0.16(RRS),0.28(SOS)和0.10μg/L(FDS).采用分子荧光光谱和紫外-可见吸收光谱、透射电镜对该缔合物的共振瑞利散射及共振非线性散射光谱进行了详细研究,并对共振增强原因及反应机理进行了探讨.在优化的实验条件下,该方法用于环境水样中Cd2+的检测与国标方法无显著性差异,效果令人满意.

In HAc-NaAc medium（pH=4.5）,it was found that Cd^2＋,phen and EY could form ternary ion association[Cd（phen）3]EY through electrostatic forces and hydrophobic forces.As a result,the new spectra of RRS,SOS and FDS appeared and their intensities significantly enhanced.The maximum peaks of RRS,SOS and FDS were at 375,732 and 372nm,respectively.The enhanced RRS,SOS and FDS intensities（ΔI）are proportional to the concentration of Cd^2＋in a certain range.The detection limits were 0.16μg/L（RRS）,0.28μg/L（SOS）and 0.10μg/L（FDS）,respectively.And the characteristics of RRS and resonance nonlinear scattering spectra were investigated in detail with molecular fluorescence spectra,ultraviolet-visible spectra and transmission electron microscopy（TEM）.The reasons of enhancement of resonance light signal and reaction mechanism were also discussed.Under optimum conditions,the method was used to detect Cd^2＋in environmental water samples with satisfactory results,and it is no significant difference with ICP-MS method in national standard of China.