Study on the interaction characteristics of dexamethasone sodium phosphate with bovine serum albumin by spectroscopic technique

作者：Wang Qian; Liu Xuyang; Su Ming; Shi Zhihong; Sun Hanwen^*

来源：New Journal of Chemistry, 2014, 38(9): 4092-4098.

DOI：10.1039/c4nj00327f

The interaction of dexamethasone sodium phosphate (DEX-P) with bovine serum albumin (BSA) was studied by fluorescence quenching in combination with UV-Vis spectroscopic method under near physiological conditions. Fluorescence quenching rate constants and binding constants for BSA-DEX-P system were determined at different temperatures. The fluorescence quenching of BSA by DEX-P was due to static quenching and energy transfer. The results of thermodynamic parameters, Delta H (-161.0 kJ mol(-1)), Delta S (-468.0 J mol(-1) K-1) and Delta G (-21.54 to -16.86 kJ mol(-1)), indicated that van der Waals interaction and hydrogen bonding played a major role in DEX-P-BSA association. Competitive experiments demonstrated that the primary binding site of DEX-P on BSA was located at site III in sub-domain IIIA of BSA. The distance between BSA and DEX-P was estimated to be 1.23 nm based on the Forster resonance energy transfer theory. The binding constant (K-a) of BSA-DEX-P at 298 K was 2.239 x 10(4) L mol(-1). Circular dichroism spectra, synchronous fluorescence and three-dimensional fluorescence studies showed that the presence of DEX-P could change the conformation of BSA during the binding process.

• 出版日期2014-9
• 单位河北大学