生物技术通报 ›› 2014, Vol. 0 ›› Issue (7): 201-208.

• 研究报告 • 上一篇    

蛋白A-葡聚糖-Fe4纳米磁珠的制备及对IgG分离纯化

任敬钢, 程超, 仲从浩, 张丽, 李荣秀   

  1. 上海交通大学微生物代谢国家重点实验室 上海交通大学生命科学技术学院, 上海 200240
  • 收稿日期:2014-01-07 出版日期:2014-07-15 发布日期:2014-07-16
  • 作者简介:任敬钢, 男, 硕士, 研究方向:仿生亲和技术在蛋白纯化上;E-mail:renjinggang@sjtu.edu.cn
  • 基金资助:
    国家科技重大专项(重大新药创制专项)(2014ZX09101043)

Fe3O4 Magnetic Dextran Nanoparticles Modified with SPA Ligand for IgG Purification

Ren Jinggang, Cheng Chao, Zhong Conghao, Zhang li, Li Rongxiu   

  1. State Key Laboratory of Microbial metabolism, and School of Life Sciences & Biotechnology, Shanghai Jiao Tong University, Shanghai 200240
  • Received:2014-01-07 Published:2014-07-15 Online:2014-07-16

摘要: 蛋白A(Staphylococcal Protein A, 简称蛋白A或SPA)是对IgG有特异性吸附能力的生物配基, 将其偶联到葡聚糖修饰的Fe3O4纳米磁珠上, 研究SPA纳米磁珠对IgG的纯化能力。采用高温多元醇法合成不同粒径的纳米磁珠, 研究磁珠粒径对IgG吸附量的影响, 并对磁珠静态载量、吸附时间、可重复性进行研究, 为工业化应用提供理论依据。通过控制反应体系中NaOH的浓度成功地合成了平均粒径从30 nm到200 nm的Fe3O4纳米磁珠, 通过吸附量试验证明了磁珠粒径对IgG吸附量有较大影响, 当磁珠平均粒径在101.5 nm时对IgG的吸附量最大, 静态吸附载量为84.85 mg/mL, 亲和常数为3.48×106 M-1。对磁珠进行5次循环再生试验后, 磁珠的吸附性能没有明显的降低。利用磁珠能高效快速地从人血清中纯化到IgG, 纯度达到93.5%(SDS-PAGE), 回收率为88.7%。因此, 这种磁性分离基质在IgG纯化中有较大的应用潜力,

关键词: 葡聚糖, 纳米磁珠, 蛋白A, IgG纯化

Abstract: The objective of present research is to prepare magnetic dextran nanoparticles conjugated with Staphylococcal Protein A(SPA-MDPs)for the purification of IgG. The magnetic nanoparticles were prepared by following a high-temperature solution-phase procedure, and the average particle size can be tuned from 30 to 200 nm by simply varying the concentration of NaOH during the reaction. The size of SPA-MDPs nanoparticles has a great influence on their adsorption capacity for IgG. A maximum adsorption of human IgG was calculated to be 84.85 mg/mL with a binding affinity constant of 3.48×106 M-1 when the average size of SPA-MDPs is about 101.5 nm. The experiment results also demonstrated that the SPA-MDPs nanoparticles can be recycled for 5 times with minor loss of adsorption capacity. Moreover, IgG was purified from human plasma with a purity of 93.5% and recovery of 88.7%. Thus, SPA-MDPs show promising potentials for isolation and purification of IgG.

Key words: Dextran, Magnetic nanoparticles, SPA, IgG purification