Synthesis and characterization of a bimodal nanoparticle based on the host-guest self-assembly for targeted cellular imaging

Multimodal imaging provides distinct advantages over traditional single modal imaging. The combined modalities of magnetic resonance imaging (MRI) and near-infrared imaging (NIR), in particular, provide a powerful tool for tumor diagnosis. In this study, a bimodal MRI and NIR self-assembled supramolecular nanoparticle was developed via the self-assembly of host-guest interactions between hyaluronic acid-beta-cyclodextrin (HA-CD) and amantadine (Ad)-modified imaging agents (Gd-DOTA and NIR cyanine dye Cy7). The supramolecular HA-CD-GC nanoparticles (NPs) were characterized by transmission electron microscopy (TEM), Zeta potential, and dynamic light-scattering (DLS) experiments. The relaxivity and fluorescent properties of the NPs were also determined. HA-CD-GC NPs exhibited an enhanced relaxivity of 11.4 mM(-1)S(-1), which was three-fold higher than that of clinical Gds(3+)-chelated complex, for MRI imaging. Moreover, HA-CD-GC NPs displayed excellent fluorescence. In addition, HA-CD-GC NPs were internalized into tumor cells via HA-receptor CD44-mediated endocytosis. Therefore, the self-assembled HA-CD-GC NPs are effective targeted tumor cell imaging systems and have potential applications in cancer diagnosis and treatment