Novel superparamagnetic iron oxide nanoparticles for tumor embolization application: preparation, characterization and double targeting.

The goal of this study was to develop novel embolic nanoparticles for targeted tumor therapy with dual targeting: magnetic field-guided and peptide-directed targeting. The embolic nanoparticles SP5.2/tTF-OCMCs-SPIO-NPs were prepared by surface-modifying of superparamagnetic iron oxide nanoparticles (SPIO-NPs) with o-carboxymethylchitosans (OCMCs) and SP5.2/tTF (SP5.2: a peptide binding to VEGFR-1; tTF: truncated tissue factor) to improve their stability and to target over-expressing VEGFR-1 cells. The physicochemical characterization results showed that the OCMCs-SPIO-NPs have a spherical or ellipsoidal morphology with an average diameter of 10-20 nm. And they possess magnetism with a saturation magnetization of 66.1 emu/g, negligible coercivity and remanence at room temperature. In addition, the confocal microscopy, Prussian blue staining and FX activation analysis respectively demonstrated the peptide-directed targeting, magnetic field-guided targeted and blood coagulation activity of the SP5.2/tTF-OCMCs-SPIO-NPs. These properties separately belong to SP5.2, Fe(3)O(4) and tTF moieties of the SP5.2/tTF-OCMCs-SPIO-NPs. Thus these SP5.2/tTF-OCMCs-SPIO-NPs with double-targeting function should have a potential application in embolization therapy of tumor blood vessels.