Site-specific in vivo targeting of magnetoliposomes using externally applied magnetic field.

Human serum albumin labeled with technetium-99m was encapsulated together with magnetite particles into phosphatidylcholine/cholesterol liposomes. In order to investigate the stability of this complex and its ability to be used for magnetic drug targeting, the in-vivo distribution after intravenous administration in rats was estimated. For in-vivo targeting an SmCo permanent magnet with intensity approximately 0.35 T was attached near the right kidney. Difference between the relative radioactivity in the magnetically targeted right kidney (25.92+/-5.84%) and non-targeted left kidney (0.93+/-0.05%) is sufficiently high for relevant clinical applications.