title: Polymer brush-modified magnetic nanoparticles for His-tagged protein purification.
abstract: Growth of poly(2-hydroxyethyl methacrylate) brushes on magnetic nanoparticles and subsequent brush functionalization with nitrilotriacetate-Ni(2+) yield magnetic beads that selectively capture polyhistidine-tagged (His-tagged) protein directly from cell extracts. Transmission electron microscopy, Fourier transform infrared (FT-IR) spectroscopy, thermogravimetric analysis, and magnetization measurements confirm and quantify the formation of the brushes on magnetic particles, and multilayer protein adsorption to these brushes results in binding capacities (220 mg BSA/g of beads and 245 mg His-tagged ubiquitin/g of beads) that are an order of magnitude greater than those of commercial magnetic beads. Moreover, the functionalized beads selectively capture His-tagged protein within 5 min. The high binding capacity and protein purity along with efficient protein capture in a short incubation time make brush-modified particles attractive for purification of recombinant proteins.
authors.affiliation: Department of Chemistry, Michigan State University , East Lansing, Michigan 48824, United States.
authors.forename: Fei
authors.initials: F
authors.lastname: Xu
authors.forename: James H
authors.initials: JH
authors.lastname: Geiger
authors.forename: Gregory L
authors.initials: GL
authors.lastname: Baker
authors.forename: Merlin L
authors.initials: ML
authors.lastname: Bruening
mesh_terms: D006639:Histidine / Q000737:chemistry*; D058185:Magnetite Nanoparticles / Q000737:chemistry*; D015394:Molecular Structure; D010316:Particle Size; D011102:Polyhydroxyethyl Methacrylate / Q000138:chemical synthesis / Q000737:chemistry*; D013499:Surface Properties; D025801:Ubiquitin / Q000737:chemistry / Q000302:isolation & purification*
chemical_list: D058185:Magnetite Nanoparticles; D025801:Ubiquitin; D011102:Polyhydroxyethyl Methacrylate; D006639:Histidine