title: Synthesis of Cationized Magnetoferritin for Ultra-fast Magnetization of Cells.
abstract: Many important biomedical applications, such as cell imaging and remote manipulation, can be achieved by labeling cells with superparamagnetic iron oxide nanoparticles (SPIONs). Achieving sufficient cellular uptake of SPIONs is a challenge that has traditionally been met by exposing cells to elevated concentrations of SPIONs or by prolonging exposure times (up to 72 hr). However, these strategies are likely to mediate toxicity. Here, we present the synthesis of the protein-based SPION magnetoferritin as well as a facile surface functionalization protocol that enables rapid cell magnetization using low exposure concentrations. The SPION core of magnetoferritin consists of cobalt-doped iron oxide with an average particle diameter of 8.2 nm mineralized inside the cavity of horse spleen apo-ferritin. Chemical cationization of magnetoferritin produced a novel, highly membrane-active SPION that magnetized human mesenchymal stem cells (hMSCs) using incubation times as short as one minute and iron concentrations as lows as 0.2 mM.
authors.affiliation: Bristol Centre for Functional Nanomaterials, University of Bristol; S.Carreira@bristol.ac.uk.
authors.forename: Sara
authors.initials: S
authors.lastname: Correia Carreira
authors.affiliation: Department of Materials, Imperial College London.
authors.forename: James P K
authors.initials: JP
authors.lastname: Armstrong
authors.affiliation: Self Assembly Group, CIC nanoGUNE; Ikebasque, Basque Foundation for Science.
authors.forename: Mitsuhiro
authors.initials: M
authors.lastname: Okuda
authors.affiliation: Bristol Centre for Functional Nanomaterials, University of Bristol.
authors.forename: Annela M
authors.initials: AM
authors.lastname: Seddon
authors.affiliation: School of Cellular and Molecular Medicine, University of Bristol.
authors.forename: Adam W
authors.initials: AW
authors.lastname: Perriman
authors.affiliation: H.H. Wills Physics Laboratory, University of Bristol.
authors.forename: Walther
authors.initials: W
authors.lastname: Schwarzacher
mesh_terms: D000818:Animals; D001052:Apoferritins / Q000737:chemistry; D006736:Horses; D006801:Humans; D007501:Iron / Q000737:chemistry; D058185:Magnetite Nanoparticles / Q000737:chemistry*; D059630:Mesenchymal Stem Cells / Q000166:cytology* / Q000378:metabolism; D013194:Staining and Labeling / Q000379:methods*
chemical_list: D058185:Magnetite Nanoparticles; D001052:Apoferritins; D007501:Iron