亲和毛细管电泳法和荧光法研究氟喹诺酮类药物与牛血清白蛋白的相互作用

Interactions Between Fluoroquinolones and Bovine Serum Albumin by Fluorescence Method and Affinity Capillary Electrophoresis

分别采用亲和毛细管电泳法和荧光法对6种氟喹诺酮类药物(司帕沙星、洛美沙星、左氧氟沙星、诺氟沙星、培氟沙星和氟罗沙星)与牛血清白蛋白的相互作用进行考察.结合比均为1∶1,结合常数在104L/mol量级,热力学参数表明体系间的相互作用力以范德华作用力和氢键力为主.另外,亲和毛细管电泳实验结果表明,缓冲溶液pH值和离子强度增大会造成结合常数在一定程度上的减小,使相互作用减弱.同时,荧光猝灭实验结合紫外光谱扫描说明体系间为静态猝灭.所得到的数据对进一步研究氟喹诺酮类药物的作用机理、提高药效和开发新一代氟喹诺酮类药物具有一定的参考意义.

The interactions between fluoroquinolones （ sparfloxacin, lomefloxacin, norfloxacin, levofloxacin, fleroxacin and pefloxacin） and bovine serum albumin were investigated by affinity capillary electrophoresis and fluorescence quenching method. The binding molar ratio was 1：1 and the values of binding constants were all at the magnitude level of 10^4 L/mol. Both van der Waals interaction and hydrogen bonds were involved in the binding process of these fluoroquinolones to BSA. The ACE results also reveal that with the increasing of buffer pH values and ionic strength, the interaction strength became weaker to a certain extent. The FL results and UV-Vis spectrum indicate that the fluorescence quenching was mainly arisen from static quenching by complex formation. The obtained results of these two methods may help us in gaining some insights on possible fluoro- quinolones/BSA interactions and in evaluating the drugs＇ pharmacokinetic profiles