UCD Centre for Nanomedicine, School of Chemistry & Chemical Biology - University, College Dublin Belfield, Dublin 4, Ireland.
Small. 2012 Aug 6;8(15):2403-11. doi: 10.1002/smll.201200099. Epub 2012 May 23.
The growth of the biopharmaceutical industry has created a demand for new technologies for the purification of genetically engineered proteins.The efficiency of large-scale, high-gradient magnetic fishing could be improved if magnetic particles offering higher binding capacity and magnetization were available. This article describes several strategies for synthesizing microbeads that are composed of a M13 bacteriophage layer assembled on a superparamagnetic core. Chemical cross-linking of the pVIII proteins to a carboxyl-functionalized bead produces highly responsive superparamagnetic particles (SPM) with a side-on oriented, adherent virus monolayer. Also, the genetic manipulation of the pIII proteins with a His(6) peptide sequence allows reversible assembly of the bacteriophage on a nitrilotriacetic-acid-functionalized core in an end-on configuration. These phage-magnetic particles are successfully used to separate antibodies from high-protein concentration solutions in a single step with a >90% purity. The dense magnetic core of these particles makes them five times more responsive to magnetic fields than commercial materials composed of polymer-(iron oxide) composites and a monolayer of phage could produce a 1000 fold higher antibody binding capacity. These new bionanomaterials appear to be well-suited to large-scale high-gradient magnetic fishing separation and promise to be cost effective as a result of the self-assembling and self-replicating properties of genetically engineered M13 bacteriophage.
生物制药行业的发展，催生了对新型技术的需求，用以实现基因工程蛋白质的纯化。如果能够获得具有更高结合能力和磁化率的磁性颗粒，大规模、高梯度的磁捕获效率将会得到提升。本文描述了几种用于合成微珠的策略，这些微珠由组装在超顺磁核上的 M13 噬菌体层组成。通过化学交联将 pVIII 蛋白与羧基功能化的微球结合，可产生对磁场响应性高的超顺磁颗粒（SPM），其具有侧向定向、附着的病毒单层。此外，通过 His（6）肽序列对 pIII 蛋白进行遗传操作，允许噬菌体以端对端的构型可逆地组装在氮三乙酸功能化的核上。这些噬菌体-磁性颗粒可成功地用于从高蛋白质浓度的溶液中一步分离抗体，纯度>90%。这些颗粒的致密磁核使它们对磁场的响应能力比由聚合物-（氧化铁）复合材料组成的商业材料高五倍，且噬菌体的单层可产生 1000 倍更高的抗体结合能力。这些新型生物纳米材料似乎非常适合大规模高梯度磁捕获分离，并且由于基因工程 M13 噬菌体的自组装和自我复制特性，有望具有成本效益。
