光谱法研究一种喹唑啉酮衍生物与牛血清白蛋白的相互作用

Study on the Interaction Between a Kind of Quinazolinones Derivatives and Bovine Serum Albumin by Spectroscopic Methods

应用荧光光谱及紫外可见光谱的方法研究了2-异丙氧基-3-苯基-3H-喹唑啉-4-酮(PHQ)与牛血清白蛋白(BSA)的相互作用。实验结果表明,PHQ能强烈猝灭牛血清白蛋白的荧光强度,其荧光猝灭机理为动态猝灭。在此基础上计算了二者相互作用的结合常数、结合位点数及ΔHθ,ΔGθ,ΔSθ等热力学参数等。结果表明PHQ与BSA以1∶1结合,其反应主要是熵驱动的,相互作用力主要为疏水作用力。根据Frster无辐射能量转移理论计算了给体(BSA)与受体(PHQ)之间的结合距离。

The interaction between 2-iropropoxy-3-phenyl-4（3H）-quinazolinones and bovine serum albumin （BSA） was studied by fluorescence spectroscopy and UV-vis absorption spectroscopy. Experimental results showed that the fluorescence intensity of BSA was quenched strongly by PHQ due to the formation of PHQ-BSA complex. The mechanism is a dynamic quenching procedure. The number of binding sites n and apparent binding constant Kb were measured by fluorescence quenching method. The corresponding thermodynamics parameters △H^θ, △G^θ,△ S^θ were calculated. The results indicated PHQ and BSA were combined with the ratio of 1 ： 1 , the reaction was driven by entropy and the interaction force was mostly hydrophobic force. The distance r between donor （BSA） and aceeptor （PHQ） was obtained according to Forster theory of non-radiation energy transfer.