pH对蛋白与氨基酸类制剂附加剂的作用和蛋白结合功能的影响  

Effect of pH on the interaction between protein and amino acid additives and protein binding function

作　　者：兰海溶 刘慧军 尹宗宁[1] LAN Hairong;LIU Huijun;YIN Zongning(Key Laboratory of Drug Targeting and Drug Delivery of Ministry of Education,West China School of Pharmacy,Sichuan University,Chengdu,Sichuan,610041 P.R.China)

机构地区：[1]四川大学华西药学院靶向药物与释药系统教育部重点实验室

出　　处：《华西药学杂志》2020年第1期7-12,共6页West China Journal of Pharmaceutical Sciences

基　　金：国家自然科学基金资助项目(批准号:81673363)

摘　　要：目的考察pH对氨基酸附加剂与牛血清白蛋白(BSA)的作用和蛋白结合功能的影响。方法采用荧光光谱法、浊度法分别研究附加剂对BSA构象稳定性和聚集程度的影响,通过计算结合常数、结合位点数以及热力学参数考察BSA的药物结合能力,最后利用新亚铜试剂研究BSA的铜离子结合能力。结果pH通过影响BSA表面芳香疏水性和表面电荷以及局部空间构象进而影响氨基酸附加剂对BSA构象的保护效应和聚集抑制作用;pH会改变BSA与药物的作用力类型、结合能力和结合位点数,BSA的铜离子结合能力随pH降低而变弱。结论pH对氨基酸附加剂与蛋白的作用及机制和物质结合能力均存在影响。OBJECTIVE To investigate the effects of pH on the interaction between amino acid excipients and BSA as well as the binding ability of BSA.METHODS The conformational stability and aggregation degree of BSA were researched by fluorescence spectroscopy and turbidity method,respectively.Moreover,the drug-binding capacity of BSA was investigated by calculating the binding constants,binding sites and thermodynamic parameters.Finally,the neocuproine spectrophotometric method was used to study the copper-binding capacity of BSA.RESULTS pH affected the aggregation and conformation protection effects of amino acid excipients on BSA by affecting the surface aromatic hydrophobic region,surface charge distribution and local specific spatial conformation of BSA.Moreover,pH could affect the type of interaction,binding capacity and number of binding sites between drugs and BSA,and change copper ion binding capacity of BSA,which decreased with the decline of pH value.CONCLUSION pH has effects on excipient-protein interaction and mechanism as well as protein drug/copper ion binding capacity.

关 键 词：PH 氨基酸附加剂 作用机制 药物结合 铜离子结合 空间构象 聚集程度 蛋白 荧光光谱法 浊度法 

分 类 号：R94[医药卫生—药剂学]