Determination Of Perfluorooctanesulfonate In The Environment By Light Scattering Technique

In this paper, the properties and analytical techniques of perfluorooctanesulfonate (PFOS) were introduced. At the same time, the light scattering (LS) analysis technique and its application were expounded. In acidic medium, PFOS can react with protonated dyes, drugs or biological macromolecules through electrostatic attraction and hydrophobic interaction to form ion-association complexes, which result in greatly enhanced LS signals. The enhanced LS intensities are in proportion to the concentration of PFOS. Thus, a series of light scattering analysis methods for the determination of PFOS were proposed, which provided simple, rapid method for the analysis of PFOS in environmental samples. Main contents are as follows:(1) This report presents a simple, ultrafast, and cost effective, rhodamine6G (Rh6G)-based resonance light scattering (RLS) assay for determination of PFOS. In pH3.29Britton-Robinson (BR) buffer medium, PFOS can react with the protonated Rh6G by electrostatic attraction and form PFOS-Rh6G ion-association complexes, which results in a greatly enhanced RLS signals. The RLS intensities at313nm are in proportion to the concentration of PFOS in the range of0.10-30.0μmol/L. The limit of detection (LOD,3a) is9.95nmol/L without preconcentration. The reaction between PFOS and Rh6G is ultrafast which finishes within just a few moments. The optimum of reaction conditions and the interferences of foreign substances were investigated. The reaction mechanism between Rh6G and PFOS were also investigated by absorption spectrum, fluorescence spectrum, scanning electron microscope (SEM) and the binary complex ratio of PFOS with Rh6G This method is successfully applied to the determination of PFOS in tap water and Jialing river samples with RSD<4.6%. Compared with the liquid-chromatography combined with mass spectrometric and gas chromatography-mass spectrometric approaches, the present approach displays the advantages of ultrafastness, simplicity and cost efficiency. (2) The RLS spectra of the interaction Quinine dihydrochloride (Quinine) with PFOS were investigated. A RLS method for the determination of PFOS has been established. In pH2.87BR buffer solution, PFOS anions can react with the protonated Quinine by electrostatic forces and hydrophobic interactions to form2:1ion-association complexes and resulting in greatly enhanced resonance light scattering signals characterized by a peak at283nm, and the RLS intensity was proportional to the concentration of PFOS in the range of0.10-5.00μmol/L. The limit of detection is9.88nmol/L. In this paper, the optimum reaction conditions and the interference of foreign substances of the system were investigated. The absorption and fluorescence spectra of the system as well as the reaction mechanism were also discussed. This RLS method has been applied to the determination of PFOS in environmental samples and human serum samples with RSD≤4.2%(3) The RLS spectra of the interaction bovine serum albumin(BSA) with PFOS were investigated. A RLS method for the determination of PFOS has been established. In pH4.10BR buffer solution, perfluorooctane sulfonate anions can react with the protonated BSA by electrostatic forces and hydrophobic interactions to form ion-association complexes and resulting in greatly enhanced resonance light scattering signals characterized by a peak at285.0nm. The RLS intensity of system is proportional to the content of PFOS in the range of0.20-25.0μmol/L. The limit of detection is20.0nmol/L. In this paper, optimum reaction conditions and interference of foreign substances were investigated. This RLS method has been applied to the determination of PFOS in environmental samples with RSD≤4.4%.(4) PFOS can quench the fluorescence of rhodamine B (RhB) in pH1.81BR 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 at340nm with that of fluorescence at596nm could be available. The linear range is from0.17to10.0μmol/L. The LOD is17.1nmol/L. The method has been applied to the determination of PFOS in environmental samples with RSD≤4.2%.