全氟辛烷磺酸与蛋白质体系的共振光散射光谱及其分析应用

研究了牛血清白蛋白(BSA)与全氟辛烷磺酸(PFOS)相互作用的共振光散射(RLS)光谱,建立了PFOS的共振光散射分析方法。 在pH值为4.1的BR缓冲溶液中,全氟辛烷磺酸根阴离子与质子化的BSA通过静电引力和疏水作用形成离子缔合物,引起共振光散射强度(IRLS)显著增强,最大散射波长位于285.0 nm处,增强的散射信号强度与PFOS浓度在0.2～25.0 μmol/L范围内呈线性关系,据此建立了测定PFOS的光散射分析方法,检出限为20.0 nmol/L。 讨论了体系的最佳反应条件及外来物质的干扰,并探讨了反应机理。 建立的共振光散射法用于环境水样中PFOS的测定,RSD≤4.4%。

Resonance Light Scattering Spectra of Perfluorooctane Sulfonate-Protein System and Its Analytical Application

The interaction of bovine serum albumin(BSA) with perfluorooctane sulfonate(PFOS) was investigated with resonance light scattering(RLS) spectroscopy.A RLS method for the determination of PFOS was established.In pH=4.1 Britton-Robinson buffer solution,perfluorooctane sulfonate anions reacted with the protonated BSA by electrostatic forces and hydrophobic interactions to form ion-association complexes and resulted in greatly enhanced resonance light scattering signals characterized by a peak at 285.0 nm.The RLS intensity of system was proportional to the content of PFOS in the range of 0.2～25.0 μmol/L,and the limit of detection was 20.0 nmol/L.The optimum reaction conditions and interference of foreign substances were investigated.This RLS method was applied to the determination of PFOS in environmental samples with RSD≤4.4%.