Abstract
A modified procedure for preparation of iron oxide nanoparticles was used to produce nanoparticles suitable for magnetic particle imaging (MPI). Cationic and anionic maghemite particles were prepared and coated by poly(N- (2-hydroxypropyl)methacrylamide)-co-N-(2-(hydroxyamino)-2-oxo-ethyl)-2-methyl-prop-2-enamide.
Bare and coated particles were characterized by magnetometry, dynamic light scattering, MR relaxometry, transmission electron microscopy and tested in vitro in a field-free-point MPI scanner. The nanoparticles were compared to Resovist and to differently oxidized particles dedicated for magnetic resonance imaging (control NP).
The cores of particles had an average diameter 8.0 nm (cationic ones) and 8.7 nm (anionic ones), hydrodynamic diameter of coated particles in water colloids was 88 nm, and zeta potential +52 mV or -60 mV for cationic or anionic particles, respectively. Cationic particles provided lower signal-to-noise ratio than Resovist during MPI, while that of anionic particles was higher by 25 %.
Also signal dispersion to surrounding voxel was smaller. The worst results (lowest signal-to-noise ratio, high signal dispersion) were reached in the case of control NP.