Abstract: 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 nm 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%.

Key words: PFOS, rhodamine B, light scattering- fluorescence ratio