Poly (hydroxyethyl methacrylate - acrylic acid) microspheres loaded with magnetically responsive Fe3O4 nanoparticles for arterial embolization, drug loading and MRI detection

In recent decades, transcatheter arterial embolization (TAE) has been attached great importance in the noninvasive vascular interventional therapy for treating various diseases. In this study, a novel magnetic embolic agent of Fe3O4-loaded hydrophilic poly (hydroxyethyl methacrylate - acrylic acid) microspheres (FPHA-Ms) was constructed using inverse suspension polymerization and sequential in situ co-precipitation method. The loading of Fe3O4 nanoparticles in FPHA-Ms was verified by infrared spectrum, vibrating sample magnetometer, X-ray diffraction and X-ray photoelectron spectroscopy, respectively. The weight percentage of iron content in lyophilized FPHA-Ms was measured by inductive coupled plasma emission spectrometer. The morphology, particle size distribution, equilibrium water content, elasticity, drug loading & eluting capacity, biosafety, magnetic resonance imaging (MRI) detectability and embolic efficacy of FPHA-Ms were systematically evaluated, respectively. FPHA-Ms possessed many merits including spherical shape, uniform and wide size range, considerable water content, high drug loading, sustained drug release and good elasticity and biocompatibility. The in vivo experiments showed FPHA-Ms could effectively block the blood supply and could be detected by MRI device. All the results proved that FPHA-Ms could serve as a novel MRI-visible multi-functional embolic agent for clinical vessel embolization, drug loading and MRI tracing in the near future.