Target-Specific Magnetic Resonance Imaging of Human Prostate Adenocarcinoma Using NaDyF-NaGdF Core-Shell Nanoparticles.

We illustrate the development of NaDyF-NaGdF core-shell nanoparticles (NPs) for targeting prostate cancer cells using a preclinical 9.4 T magnetic resonance imaging (MRI) of live animals. The NPs composed of paramagnetic Dy and Gd (- and -contrast agents, respectively) demonstrate proton relaxivities of = 20.2 mM s and = 32.3 mM s at clinical 3 T and = 9.4 mM s and = 144.7 mM s at preclinical 9.4 T. The corresponding relaxivity values per NP are = 19.4 × 10 mM s and = 33.0 × 10 mM s at 3 T and = 9.0 × 10 mM s and = 147.0 × 10 mM s at 9.4 T. active targeting of human prostate tumors grown in nude mice revealed docking of anti-prostate-specific membrane antigen (PSMA) antibody-tagged NPs at tumor sites post-24 h of their intravenous injection. On the other hand, passive targeting showed preferential accumulation of NPs at tumor sites only within 2 h of their injection, ascribed to the enhanced permeation and retention effect of the tumor. A biodistribution study employing the harvested organs of mice, post-24 h injection of NPs, quantified active targeting as nearly twice as efficient as passive targeting. These outcomes provide potential opportunities for noninvasive diagnosis using NaDyF-NaGdF core-shell NPs for target-specific MRI.