盐种类和浓度对蛋白质疏水性吸附过程有效孔扩散系数的影响  

Effect of salt type and concentration on effective pore diffusion coefficient in protein hydrophobic adsorption

作　　者：刘建华[1] 史清洪[1] 陈捷[1] 孙彦[1] 

机构地区：[1]天津大学化工学院生物化工系,天津300072

出　　处：《化工学报》2006年第1期79-84,共6页CIESC Journal

基　　金：国家自然科学基金项目(20476082).~~

摘　　要：研究了牛血清白蛋白在配基密度不同的两种疏水性吸附剂Phenyl Sepharose FFlowsub和Phenyl Sepha-rose FF high sub上的吸附平衡和孔内传质动力学,重点考察了盐种类和浓度的影响.结果表明,Na2SO4溶液中盐浓度的增加导致蛋白质吸附容量的增大和解离常数的降低比(NH4)2SO4溶液更显著.利用孔扩散模型得到的有效扩散系数随盐浓度及配基密度的增大而提高,表明表面扩散作用对孔内传质的贡献随吸附容量提高而增大.The adsorption equilibria and kinetics of bovine serum albumin （BSA） on two hydrophobic adsorbents, Phenyl Sepharose FF low sub and Phenyl Sepharose FF high sub were investigated in the presence of different salt types and salt concentrations. The results indicated that an increasing salt concentration led to an enhanced adsorption capacity and a decreased dissociation constant, in particular in the salt system of sodium sulfate. Then, the effective pore diffusivity of BSA was predicted by fitting the pore diffusion model to the dynamic batch adsorption data. The results showed that effective pore diffusion coefficient increased with increasing salt concentration as well as ligand density. It was considered due to the enhanced contribution of surface diffusion to the interior mass transfer at high salt concentration and ligand density because of enhanced adsorption capacity under such conditions.

关 键 词：疏水性吸附 牛血清白蛋白 孔扩散 表面扩散 孔扩散系数 

分 类 号：O647.31[理学—物理化学] TQ936.2[理学—化学]