MRI manifestation of novel superparamagnetic iron oxide nanoparticles in the rat inner ear
Jing Zou1, Weikai Zhang, Dennis Poe
1Department of Otolaryngology, University of Tampere, FM1, 3rd Floor, Biokatu 6, 33520 Tampere, Finland. jing.zou@uta.fi
Aim:
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.
Materials & 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.
Results & Conclusion:
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.
