%0 Journal Article %T Improved Transversal Relaxivity for Highly Crystalline Nanoparticles of Pure γ-Fe2 O3 Phase %+ Institut des Sciences Chimiques de Rennes (ISCR) %+ Laboratoire de chimie de coordination (LCC) %+ Centre d'élaboration de matériaux et d'études structurales (CEMES) %+ Surfaces, Interfaces et Nano-Objets (CEMES-SINanO) %+ Structure Fédérative de Recherche en Biologie et Santé de Rennes ( Biosit : Biologie - Santé - Innovation Technologique ) %+ Plate-forme Rennaise d'Imagerie et Spectroscopie Structurale et Métabolique (PRISM) %A Casterou, Gérald %A Collière, Vincent %A Lecante, Pierre %A Coppel, Yannick %A Eliat, Pierre-Antoine %A Gauffre, Fabienne %A Kahn, Myrtil L. %Z Conseil National de la Recherche Scientifique %Z ARED 6951, Région Bretagne %< avec comité de lecture %@ 0947-6539 %J Chemistry - A European Journal %I Wiley-VCH Verlag %V 21 %N 51 %P 18855–18861 %8 2015 %D 2015 %R 10.1002/chem.201502905 %M 26542051 %K nanoparticles %K magnetic properties %K Iron %K imaging agents %K polymers %Z Chemical SciencesJournal articles %X Pure and highly crystalline γ-Fe2 O3 nanocrystals (NCs) are obtained when hydrolysis and oxidation of a Fe(II) organometallic precursor are performed in successive steps. Their synthesis in pure alkylamine leads to NCs of about 6 nm. In aqueous solutions of poly(vinyl)pyrrolidone, such pristine NCs form aggregates of about 150 nm that exhibit a high transversal relaxivity (r2 =466 mM(-1)  s(-1) ) about four times higher than that of a commercial Feridex magnetic resonance imaging (MRI) contrast agent. Consequently, they provide a significant decrease in the NMR signal at very short echo time (8 ms), which is of paramount importance in clinical practice because of the reduced duration of MRI measurements %G English %L hal-01231170 %U https://univ-rennes.hal.science/hal-01231170 %~ UNIV-TLSE3 %~ UNIV-RENNES1 %~ CNRS %~ INSA-RENNES %~ INSA-TOULOUSE %~ ENSC-RENNES %~ IRSTEA %~ INRA %~ IFR140 %~ ISCR %~ SCR_ICMV %~ LCC %~ STATS-UR1 %~ BIOSIT %~ UR1-SPM %~ INC-CNRS %~ UR1-UFR-SPM %~ UR1-HAL %~ ISCR-CORINT %~ UR1-SDLM %~ UR1-SDLMJONCH %~ UR1-SDV %~ AGREENIUM %~ CEMES %~ SINANO %~ TEST-UNIV-RENNES %~ TEST-UR-CSS %~ UNIV-RENNES %~ INSA-GROUPE %~ CNANO-R %~ ISCR-CORINT1 %~ INRAE %~ UR1-MMS %~ TOULOUSE-INP %~ UNIV-UT3 %~ UT3-INP %~ UT3-TOULOUSEINP %~ TEST2-HALCNRS