在pH 6.8 Britton-Robinson(BR)缓冲介质中,镉(Ⅱ)与1,10-菲啰啉(Phen)作用后与全氟辛烷磺酸(PFOS)形成离子缔合物,使体系的共振光散射信号显著增强.最大散射峰位于307.0 nm处,其增强散射信号强度与镉(Ⅱ)的浓度在6.0—342.5 ng·mL-1范围内呈线性关系,据此建立了测定镉(Ⅱ)含量的共振光散射分析方法,检出限(3!)为0.6 ng·mL-1,研究了反应产物的RLS光谱特征,适宜的反应条件和影响因素,考察了共存物质的影响.该方法用于自来水和实验室废水样中镉(Ⅱ)的测定,RSD≤4.4%.
In pH 6.8 Britton-Robinson (BR) buffer, a resonance light scattenng (RLS) anatyucal ,for Cd( Ⅱ) was established. The method is based on the enhanced RLS signal due to the interaction of PFOS with the complex formed between Cd ( Ⅱ) and 1,10-phenanthorline (Phen). The enhanced RLS intensity at 307.0 nm is proportional to the content of Cd (Ⅱ) in a range of 6.0--342.5 ng.mL- 1. The limit of detection (3σ) is 0. 6 ng'mL-1 The optimum reaction conditions and the interference of foreign substances were investigated. This method was successfully applied to the determination of Cd( Ⅱ) in tap water and laboratory waste water samples with RSD ≤4.4%.