Resonance Rayleigh scattering of anionic surfactant-protein systems and their analytical application

in acid medium, proteins can react with anionic surfactant to form ion-association complexes, leading to great enhancement of resonance Rayleigh scattering (RRS). Taking sodium dodecyl sulfate (SDS)-bovine serum albamin (BSA) system as an example, the corresponding characteristics of RRS spectra, the influencing factors and the optimum reaction conditions were investigated. The intensity of RRS is directly proportional to the concentration of protein in the range of 0 similar to 5 mg/L or 0 similar to 10 mg/L depending on different proteins. The method has high sensitivity, and the detection limits for proteins are in the range from 17 similar to 180 mug/L. Moreover the method has wider linear range, good selectivity, and better repeatability. This method has been applied to the determination of proteins on synthetic samples and human serum samples with satisfactory results.