title: Physicochemical characterization of ultrasmall superparamagnetic iron oxide particles (USPIO) for biomedical application as MRI contrast agents.
abstract: Ultrasmall superparamagnetic iron oxide (USPIO) particles are maghemite or magnetite nanoparticles currently used as contrast agent in magnetic resonance imaging. The coatings surrounding the USPIO inorganic core play a major role in both the in vitro stability and, over all, USPIO's in vivo fate. Different physicochemical properties such as final size, surface charge and coating density are key factors in this respect. Up to now no precise structure--activity relationship has been described to predict entirely the USPIOs stability, as well as their pharmacokinetics and their safety. This review is focused on both the classical and the latest available techniques allowing a better insight in the magnetic core structure and the organic surface of these particles. Concurrently, this work clearly shows the difficulty to obtain a complete physicochemical characterization of USPIOs particles owing to their small dimensions, reaching the analytical resolution limits of many commercial instruments. An extended characterization is therefore necessary to improve the understanding of the properties of USPIOs when dispersed in an aqueous environment and to set the specifications and limits for their conception.
authors.affiliation: Univ Paris-Sud, Châtenay Malabry, France.
authors.forename: Mariagrazia
authors.initials: M
authors.lastname: Di Marco
authors.forename: Claudia
authors.initials: C
authors.lastname: Sadun
authors.forename: Marc
authors.initials: M
authors.lastname: Port
authors.forename: Irene
authors.initials: I
authors.lastname: Guilbert
authors.forename: Patrick
authors.initials: P
authors.lastname: Couvreur
authors.forename: Catherine
authors.initials: C
authors.lastname: Dubernet
mesh_terms: D003287:Contrast Media / Q000737:chemistry*; D003911:Dextrans; D052203:Ferrosoferric Oxide; D007089:Image Enhancement / Q000379:methods*; D007501:Iron / Q000737:chemistry*; D008279:Magnetic Resonance Imaging / Q000379:methods*; D058185:Magnetite Nanoparticles; D053758:Nanoparticles / Q000737:chemistry* / Q000648:ultrastructure*; D010087:Oxides / Q000737:chemistry*; D010316:Particle Size
chemical_list: D003287:Contrast Media; D003911:Dextrans; D058185:Magnetite Nanoparticles; D010087:Oxides; C097921:ferumoxtran-10; D007501:Iron; D052203:Ferrosoferric Oxide