Jianghong Tang, Ning Lian, Xianghong He
Oct 29, 2008
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Influential Citations
18
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Journal
Journal of Molecular Structure
Abstract
Abstract The interaction of sophoricoside and human serum albumin (HSA) was investigated by UV-absorption, fluorescence spectroscopy and Fourier transform infrared (FT-IR) spectroscopy at simulative physiological pH with sophoricoside concentrations of 3.0 × 10 −6 to 2.3 × 10 −5 mol L −1 . The experimental results suggested that the intrinsic fluorescence of HSA was quenched by addition of sophoricoside through static quenching mechanism. The interaction between sophoricoside and HSA was occurred via a single class of binding site. The binding constants at 290, 301, 310 and 318 K were 6.19 × 10 4 , 4.69 × 10 4 , 3.54 × 10 4 , 3.11 × 10 4 L mol −1 , respectively. In the presence of sophoricoside the protein secondary structure changed in aqueous solution. The standard enthalpy change (−19.44 kJ mol −1 ) and standard entropy change (24.71 J mol −1 K −1 ) of the binding reaction revealed that hydrophobic interaction was the predominant binding force. In addition, molecular modeling showed that sophoricoside was bound within the subdomain IIA of the HSA.