摘要
运用荧光光谱法研究了生理酸度(pH=7.4)条件下,农药利谷隆、非草隆分别与牛血清白蛋白(BSA)相互作用。测定了不同温度下两种农药与BSA结合的猝灭常数、结合常数和结合位点数,结果表明,利谷隆和非草隆对BSA的内源荧光有较强的猝灭作用,利谷隆、非草隆对BSA的荧光猝灭过程分别为动态猝灭和静态猝灭。由van’t Hoff方程式计算出利谷隆、非草隆与BSA反应的热力学参数,焓变(ΔH)和熵变(ΔS)值分别为18.59 kJ.mol-1、131.09 J.mol-1.K-1和-21.64 kJ.mol-1、19.94 J.mol-1.K-1,表明利谷隆与BSA的作用力是以疏水作用为主,而非草隆与BSA之间的作用力主要是静电引力,且反应过程均为自发过程。金属离子K+、Ca2+、Mg2+或Al3+的存在,会影响利谷隆、非草隆与BSA的结合常数。
The interaction of linuron or fenuron with bovine serum albumin（BSA） in physiological buffer （pH = 7.4） was studied by fluorescence spectroscopy. The quenching constant, binding constant and number of binding sites were obtained at different temperatures. The results indicated that there was a strong fluorescence quenching reaction of linuron or fenuron to BSA. The quenching mechanism of fluorescence of BSA by linuron or fenuron was suggested as dynamic quenching and static quenching, respectively. The thermodynamic parameters of the interaction between linuron or fenuron with BSA were measured according to the van＇ s Hoff Equation, the enthalpy change （AH） and the entropy change （AS） of BSA-linuron system and BSA-fenuron system were calculated to be 18.59 kJ · mol^-1 , 131.09 J · mol^-1 · K^-1 and -21.64 kJ · mol^-1, 19.94 J · mol^-1 · K^-1 , respectively, which indicated that the interaction of linuron with BSA was driven mainly by hydrophobic force, whereas the interaction between fenuron and BSA was driven mainly by electrostatic force. It was showed that the reaction processes of the two systems were occurred spontaneously since values of Gibbs free energy change （AG） were negative. The binding constant of linuron or fenuron to BSA was influenced in the presence of K ^＋ , Ca^2＋ , Mg^2＋ or Al^3＋.
出处
《南昌大学学报（工科版）》
CAS
2008年第4期307-310,共4页
Journal of Nanchang University(Engineering & Technology)
基金
江西省自然科学基金资助项目(2007GZH1924)
教育部长江学者和创新团队发展计划资助项目(IRT0540)
江西省教育厅科学基金资助项目(GJJ08025)
关键词
农药
牛血清白蛋白
荧光猝灭
热力学参数
pesticide
bovine serum albumin
fluorescence quenching
thermodynamic parameter
