光散射/荧光比率法测定全氟辛烷磺酸

摘要

在pH=1.81的Britton-Robinson(BR)缓冲溶液中,全氟辛烷磺酸(PFOS)与罗丹明B(RhB)通过静电引力和疏水作用使RhB的光散射增强,荧光发生猝灭.利用在普通荧光光度计上单次扫描获得的340nm处的光散射强度(I340)与596 nm处的荧光强度(F596)之比,建立了测定PFOS的光散射/荧光比率法,检出限(3σ)为17 nmol/L.方法用于环境水样中PFOS的测定,RSD≤4.2％.%Perfluorooctane sulfonate (PFOS) can quench the fluorescence of rhodamine B ( RhB) in pH = 1.81 Britton-Robinson(BR) buffer solution,and results in light scattering enhancement by electrostatic forces and hydrophobic interactions.In this work,a light scattering-fluorescence ratio method of PFOS was established with a common spectrofluorometer by measuring the light emission signals through one scanning,out of which a ratio of the intensity of light scattering at 340 ran to that of fluorescence at 596 nm could be obtained.The linear range is from 0.17 to 10.0 μmol/L,and the limit of detection(3σ) is 17 nmol/L.The method has been applied to the determination of PFOS in the environmental samples with RSD ≤4.2%.