Biomedical applications of magnetic fluids. I. Magnetic guidance of ferro-colloid-entrapped albumin microsphere for site specific drug delivery in vivo.

Abstract
Magnetic guidance of magnetic albumin microsphere for site specific drug delivery was investigated in vivo. After intravenous injection in mice, magnetic microspheres localized in the site (lung) at which two permanent magnets were placed. Injection into the renal artery in rats also indicated that the microspheres were concentrated at the kidney by a magnetic field. When magnet was not applied, however, the microspheres were concentrated mainly in the liver. Such preferential localization by magnetic means suggested that magnetic albumin microspheres could become effective drug carriers with site specificity for the delivery of chemotherapeutic agents in cancer therapy.