title: Surface modification of superparamagnetic nanoparticles (Ferrofluid) studied with particle electrophoresis: application to the specific targeting of cells.
abstract: Colloidal aqueous suspension of superparamagnetic nanoparticles (9 nm in diameter) composed of maghemite (gamma Fe2O3) and forming an ionic ferrofluid in aqueous solution are covalently coupled with lectins, enzymes or antibodies, using specific thiol chemistry. The surface charge modifications of nanoparticles, caused by ligand coupling, were monitored by measuring their electrophoretic mobilities using laser-Doppler velocimetry. Particle electrophoretic mobility (PEM) changes are shown to correlate well with the amount of ligand fixed on the particles, as probed by its biological activity. The PEM method provides a useful tool to optimize ligand immobilization at the surface of nanoparticles, and may be advantageous when biological activity measurements are not convenient.
authors.affiliation: Ecole Nationale Vétérinaire de Maisons-Alfort, Physico-Chimie, France. sestier@vet-alfort.fr
authors.forename: C
authors.initials: C
authors.lastname: Sestier
authors.forename: M F
authors.initials: MF
authors.lastname: Da-Silva
authors.forename: D
authors.initials: D
authors.lastname: Sabolovic
authors.forename: J
authors.initials: J
authors.lastname: Roger
authors.forename: J N
authors.initials: JN
authors.lastname: Pons
mesh_terms: D000818:Animals; D002460:Cell Line; D004586:Electrophoresis / Q000379:methods*; D005290:Ferric Compounds / Q000138:chemical synthesis / Q000737:chemistry*; D052203:Ferrosoferric Oxide; D006801:Humans; D006825:Hybridomas; D007501:Iron / Q000737:chemistry; D017078:Laser-Doppler Flowmetry / Q000379:methods; D008280:Magnetics; D051379:Mice; D008810:Mice, Inbred C57BL; D008819:Mice, Nude; D010087:Oxides / Q000737:chemistry; D010316:Particle Size; D013499:Surface Properties
chemical_list: D005290:Ferric Compounds; D010087:Oxides; D007501:Iron; D052203:Ferrosoferric Oxide