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Determination of Protein-ligand Interactions Using Differential Scanning Fluorimetry
Published on: September 13, 2014
Determination of proteins with Alizarin Red S by Rayleigh light scattering technique
Hui Zhong1, Na Li, Fenglin Zhao
1Department of Chemistry, Huaiyin Normal College, Jiangsu 223001, China.
Abstract:
A new protein determination method by enhanced Rayleigh light scattering (RLS) technique has been developed. In acid condition (pH=3.60), RLS of 1,2-dihydroxyanthraquinone-3-sulfonate (Alizarin Red S) can be greatly enhanced by addition of proteins, resulting in two characteristic peaks, 360 and 505nm, respectively. The new protein assay is based on the RLS enhancement and spectrum change. The optimum condition for the reaction was investigated. The linear range is 0.20-24.9mugml(-1) for BSA and 0.20-15.5mugml(-1) for HSA. The detection limits (S/N=3) are 9.59ngml(-1) for BSA and 9.51ngml(-1) for HSA. The results of determination for human serum samples were comparable to those obtained by Bradford method. The binding stoichiometry was determined.
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