应用荧光光度法研究3,5-二溴水杨醛缩牛磺酸席夫碱与牛血清白蛋白相互作用

Study on Interaction of 3,5-Dibromo-salicylaldehyde-taurine Schiff Base with Bovine Serum Albumin by Fluorospectrophotometry

摘要: 应用紫外分光光度法和荧光光度法研究了3,5-二溴水杨醛缩牛磺酸席夫碱(DSTSB)在pH 3.2的介质中,与牛血清白蛋白(BSA)的相互作用(结合作用),考察了DSTSB对BSA构象的影响.讨论了DSTSB对BSA内源荧光的淬灭机理,测得猝灭常数Kq=2.1×1014L·mol-1·s-1,结合常数(KA=6.31×108L·mol-1)和结合点位数(n=1.172 5).依据Frester辐射能量转移理论确定了荧光给体-受体间距离(r=3.67 nm).

Abstract: The interaction beween 3,5-dibromo-salicylaldehyde-taurine Schiff base (DSTSB) and bovine serum albumin(BSA) in aqueous solution of pH 3.2 was studied by UV spectrophotometry and fluorospectrophotometry.Effect of DSTSB on the configuration of BSA was also studied.Mechanism of quenching of fluorescence of BSA by DSTSB was discussed.Quenching constant (Kq),equilibrium constant of combination (KA) and number of combination site (n) were determined and values obtained were 2.1 ×1014L·mol-1·s-1,6.31×108L·mol-1 and 1.172 5 respectively.By the Frester radiating energy transfer theory,the value of combination distance between the donor and acceptor was found to be 3.67 nm.