title: MRI manifestation of novel superparamagnetic iron oxide nanoparticles in the rat inner ear.
abstract: OBJECTIVE
  Superparamagnetic iron oxide nanoparticles hierarchically coated with oleic acid and Pluronic F127 copolymers (POA@SPION) have shown exceptional T2 contrast enhancement. The aim of the present work was to investigate the MRI manifestation of POA@SPION in the inner ear.
  
  
  METHODS
  A total of 26 male Wister rats were selected for testing POA@SPION administered through intracochlear, intratympanic and intravenous routes. MRI was performed with a 4.7 T MR scanner.
  
  
  CONCLUSIONS
  POA@SPION can be introduced into the perilymph space, after which it becomes widely distributed and can demonstrate the integrity of the perilymph-endolymph barrier. Positive highlighting of the endolymph compartment against the darkened perilymph was visualized for the first time. POA@SPION passed through the middle-inner ear barriers in only small amounts, but stayed in the perilymph for 3 days. They did not traverse the blood-perilymph barrier or blood-endolymph barrier. The inner ear distribution of POA@SPION was confirmed by histology. POA@SPION is a promising T2 negative contrast agent.
authors.affiliation: Department of Otolaryngology, University of Tampere, FM1, 3rd Floor, Biokatu 6, 33520 Tampere, Finland. jing.zou@uta.fi
authors.forename: Jing
authors.initials: J
authors.lastname: Zou
authors.forename: Weikai
authors.initials: W
authors.lastname: Zhang
authors.forename: Dennis
authors.initials: D
authors.lastname: Poe
authors.forename: Jian
authors.initials: J
authors.lastname: Qin
authors.forename: Andrea
authors.initials: A
authors.lastname: Fornara
authors.forename: Ya
authors.initials: Y
authors.lastname: Zhang
authors.forename: Usama Abo
authors.initials: UA
authors.lastname: Ramadan
authors.forename: Mamoun
authors.initials: M
authors.lastname: Muhammed
authors.forename: Ilmari
authors.initials: I
authors.lastname: Pyykkö
mesh_terms: D000818:Animals; D003287:Contrast Media / Q000737:chemistry* / Q000378:metabolism; D007758:Ear, Inner / Q000033:anatomy & histology* / Q000378:metabolism; D004710:Endolymph / Q000378:metabolism; D005290:Ferric Compounds / Q000737:chemistry*; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008280:Magnetics; D008297:Male; D053758:Nanoparticles / Q000737:chemistry* / Q000648:ultrastructure; D019301:Oleic Acid / Q000737:chemistry; D010498:Perilymph / Q000378:metabolism; D020442:Poloxamer / Q000737:chemistry; D051381:Rats; D017208:Rats, Wistar
chemical_list: D003287:Contrast Media; D005290:Ferric Compounds; D020442:Poloxamer; C000499:ferric oxide; D019301:Oleic Acid