Thrombosis is closely related to the instability of intracranial aneurysm (IA), whose rupture is associated with high morbidity and mortality. It is difficult to detect an IA-related thrombus because traditional magnetic resonance imaging (MRI) and even contrast-enhanced MRI cannot clearly distinguish a thrombus from the surrounding tissues. Herein, a nanoplatform [(MFe2O4-ZnDPA nanoparticles (NPs)], consisting of Zn0.4Co0.6Fe2O4@Zn0.4Mn0.6Fe2O4 NPs for imaging and Zn(II)-bis(dipicolylamine) (ZnDPA) for thrombus targeting, is constructed to target an experimental aneurysm-related thrombus in rabbits via MRI. In vitro experiments including platelet safety evaluation primarily prove that MFe2O4-ZnDPA NPs with a high MRI transverse relaxation time (T2) have good biocompatibility. MFe2O4-ZnDPA NPs could target a thrombus via the special interaction between ZnDPA and phosphatidylserine of activated platelets in the thrombus through MRI and Fe quantification assays. Moreover, after MFe2O4-ZnDPA NPs are injected into the ear vein of common carotid artery aneurysm model rabbits, MRI shows that MFe2O4-ZnDPA NPs could accumulate in the aneurysm-related thrombus from 0 to 15 min after injection and decrease in the next 45 min. Meanwhile, MFe2O4-ZnDPA NPs could decrease the MRI T2 signal of the aneurysm-related thrombus to enhance the outline of the aneurysm. This study demonstrates that a nanoplatform can enhance the detection of an aneurysm-related thrombus as well as aneurysm itself to assist further treatment of IA.
Keywords: Zn(II)-bis(dipicolylamine); aneurysms; magnetic resonance imaging; rabbits; thrombus.