SCI和EI收录∣中国化工学会会刊

›› 2017, Vol. 25 ›› Issue (7): 906-910.DOI: 10.1016/j.cjche.2017.02.003

• Separation Science and Engineering • 上一篇    下一篇

Implications from protein uptake kinetics onto dextran-grafted Sepharose FF coupled with ion exchange and affinity ligands

Aiying Xue, Linling Yu, Yan Sun   

  1. Department of Biochemical Engineering and Key Laboratory of Systems Bioengineering of the Ministry of Education, School of Chemical Engineering and Technology, Tianjin University, Tianjin 300072, China
  • 收稿日期:2016-12-07 修回日期:2017-02-25 出版日期:2017-07-28 发布日期:2017-08-17
  • 通讯作者: Yan Sun,E-mail address:ysun@tju.edu.cn
  • 基金资助:
    Supported by the National Natural Science Foundation of China (21236005, 21621004).

Implications from protein uptake kinetics onto dextran-grafted Sepharose FF coupled with ion exchange and affinity ligands

Aiying Xue, Linling Yu, Yan Sun   

  1. Department of Biochemical Engineering and Key Laboratory of Systems Bioengineering of the Ministry of Education, School of Chemical Engineering and Technology, Tianjin University, Tianjin 300072, China
  • Received:2016-12-07 Revised:2017-02-25 Online:2017-07-28 Published:2017-08-17
  • Supported by:
    Supported by the National Natural Science Foundation of China (21236005, 21621004).

摘要: Our previous studies have reported the presence of "chain delivery" effects of protein adsorption onto ion exchangers with polymer-grafted ion-exchange groups, such as dextran-grafted and poly(ethylenimine)-modified Sepharose gels. However, it is unclear if the "chain delivery" occurs on affinity adsorption with specific interactions. This work is designed to address this issue. A dextran-grafted Sepharose gel was prepared, and then the matrix was modified using diethylaminoethyl, a typical ion-exchange group, or octapeptide (FYCHWQDE), an affinity ligand for human immunoglobulin G (hIgG) to prepare ion-exchange or affinity adsorbents, respectively. Results of hIgG adsorption showed that the uptake rate represented by the effective diffusivity of hIgG onto the dextran-grafted ion exchangers was obviously enhanced by the dextran grafting, indicating the presence of "chain delivery" of the bound proteins on the charged groups on the dextran chains. By contrast, the effective diffusivity of hIgG changed little as ligand density increased on the dextran-grafted FYCHWQDE adsorbents. Their adsorption capacities decreased and effective diffusivities were not accelerated by the dextran grafting. Thus, this work clarified that grafted dextran could not accelerate hIgG uptake rate on the affinity resins, or in other words, chain delivery did not occur on the specific interaction-based affinity adsorption.

关键词: Dextran-grafted adsorbent, Ion exchange chromatography, Affinity chromatography, Immunoglobulin G, Kinetics

Abstract: Our previous studies have reported the presence of "chain delivery" effects of protein adsorption onto ion exchangers with polymer-grafted ion-exchange groups, such as dextran-grafted and poly(ethylenimine)-modified Sepharose gels. However, it is unclear if the "chain delivery" occurs on affinity adsorption with specific interactions. This work is designed to address this issue. A dextran-grafted Sepharose gel was prepared, and then the matrix was modified using diethylaminoethyl, a typical ion-exchange group, or octapeptide (FYCHWQDE), an affinity ligand for human immunoglobulin G (hIgG) to prepare ion-exchange or affinity adsorbents, respectively. Results of hIgG adsorption showed that the uptake rate represented by the effective diffusivity of hIgG onto the dextran-grafted ion exchangers was obviously enhanced by the dextran grafting, indicating the presence of "chain delivery" of the bound proteins on the charged groups on the dextran chains. By contrast, the effective diffusivity of hIgG changed little as ligand density increased on the dextran-grafted FYCHWQDE adsorbents. Their adsorption capacities decreased and effective diffusivities were not accelerated by the dextran grafting. Thus, this work clarified that grafted dextran could not accelerate hIgG uptake rate on the affinity resins, or in other words, chain delivery did not occur on the specific interaction-based affinity adsorption.

Key words: Dextran-grafted adsorbent, Ion exchange chromatography, Affinity chromatography, Immunoglobulin G, Kinetics