title: Compact zwitterion-coated iron oxide nanoparticles for biological applications.
abstract: The potential of superparamagnetic iron oxide nanoparticles (SPIONs) in various biomedical applications, including magnetic resonance imaging (MRI), sensing, and drug delivery, requires that their surface be derivatized to be hydrophilic and biocompatible. We report here the design and synthesis of a compact and water-soluble zwitterionic dopamine sulfonate (ZDS) ligand with strong binding affinity to SPIONs. After ligand exchange, the ZDS-coated SPIONs exhibit small hydrodynamic diameters, and stability with respect to time, pH, and salinity. Furthermore, small ZDS coated SPIONs were found to have a reduced nonspecific affinity (compared to negatively charged SPIONs) toward serum proteins; streptavidin/dye functionalized SPIONs were bioactive and thus specifically targeted biotin receptors.
authors.affiliation: Department of Chemistry, Massachusetts Institute of Technology, 77 Massachusetts Avenue, Cambridge, Massachusetts 02139, USA.
authors.forename: He
authors.initials: H
authors.lastname: Wei
authors.forename: Numpon
authors.initials: N
authors.lastname: Insin
authors.forename: Jungmin
authors.initials: J
authors.lastname: Lee
authors.forename: Hee-Sun
authors.initials: HS
authors.lastname: Han
authors.forename: Jose M
authors.initials: JM
authors.lastname: Cordero
authors.forename: Wenhao
authors.initials: W
authors.lastname: Liu
authors.forename: Moungi G
authors.initials: MG
authors.lastname: Bawendi
mesh_terms: D000476:Alkanesulfonates / Q000737:chemistry*; D001798:Blood Proteins / Q000737:chemistry*; D020099:Coated Materials, Biocompatible / Q000737:chemistry*; D003911:Dextrans / Q000737:chemistry*; D004298:Dopamine / Q000737:chemistry*; D058185:Magnetite Nanoparticles / Q000737:chemistry*; D008422:Materials Testing; D049329:Nanostructures / Q000737:chemistry* / Q000648:ultrastructure*; D010316:Particle Size; D011485:Protein Binding
chemical_list: D000476:Alkanesulfonates; D001798:Blood Proteins; D020099:Coated Materials, Biocompatible; D003911:Dextrans; D058185:Magnetite Nanoparticles; C097921:ferumoxtran-10; D004298:Dopamine