摘要
Three （2E）-3-（4＇-halophenyl）prop-2-enoyl sulfachlorpyridazine sodium salts（XPSCA） were synthesized. Their chemical structures were confirmed by IH NMR and 13C NMR, electrospray ionization mass spectrometry （ESI-MS）, and infrared（IR） spectroscopy. The interactions between XPSCA and bovine serum albumin（BSA） were investigated under imitated physiological condition by fluorescence quenching technique and UV-Vis absorption spectroscopy according to the Stern-Volmer equation. The results from the emission quenching at different tempera- tures indicate that the quenching mechanism of serum albumin by XPSCA was static quenching mechanism at low XPSCA concentrations or a combined quenching（static and dynamic） mechanism at higher XPSCA concentrations. At different temperatures, the binding constant and the binding sites of XPSCA with BSA were investigated, and the distances were evaluated according to F6rster non-radiative resonance energy transfer theory. The thermodynamic parameters were calculated according to van＇t Hoff equation, which implies that both van der Waals interaction and hydrogen bond played major roles in stabilizing the XPSCA-BSA complexes, whereas hydrophobic interactions were secondary. Moreover, the conformational changes in BSA were analyzed by synchronous fluorescence spectra.
Three （2E）-3-（4＇-halophenyl）prop-2-enoyl sulfachlorpyridazine sodium salts（XPSCA） were synthesized. Their chemical structures were confirmed by IH NMR and 13C NMR, electrospray ionization mass spectrometry （ESI-MS）, and infrared（IR） spectroscopy. The interactions between XPSCA and bovine serum albumin（BSA） were investigated under imitated physiological condition by fluorescence quenching technique and UV-Vis absorption spectroscopy according to the Stern-Volmer equation. The results from the emission quenching at different tempera- tures indicate that the quenching mechanism of serum albumin by XPSCA was static quenching mechanism at low XPSCA concentrations or a combined quenching（static and dynamic） mechanism at higher XPSCA concentrations. At different temperatures, the binding constant and the binding sites of XPSCA with BSA were investigated, and the distances were evaluated according to F6rster non-radiative resonance energy transfer theory. The thermodynamic parameters were calculated according to van＇t Hoff equation, which implies that both van der Waals interaction and hydrogen bond played major roles in stabilizing the XPSCA-BSA complexes, whereas hydrophobic interactions were secondary. Moreover, the conformational changes in BSA were analyzed by synchronous fluorescence spectra.
基金
Supported by the National Natural Science Foundation of China（No.20962002） and the Natural Science Foundation of Gungxi Zhuang Autonomous Region, China（No. 2013 GXNSFDA019005）.
