Site-Specific Drug Targeting with Fluorouracil Microspheres

Abstract

The disposition of 5-fluorouracil following intra-arterial administration in albino rats, as a free drug suspension (control) or via magnetic albumin microspheres (treatment group) in normal saline, has been investigated. The rat tail was used as the target model wherein fluorouracil microspheres were injected into the ventral caudal artery. A magnetic field of 6000 G was directed toward a predetermined site on the tail. On analysis, it was observed that the magnetically responsive albumin microspheres of fluorouracil showed an increase in drug retention at the target site and liver. However, drug retention in the heart, kidney, and tissues in close proximity to the target site was considerably less. It was also observed that the amount of drug retained in nontarget sites (heart, kidney, and lungs) was less when fluorouracil was administered in the microsphere form rather than as a suspension. This results in low drug exposure of nontarget organs with the microsphere form, which would otherwise have exhibited toxicity effects.

Key Words :

• Albumin
• Fluoroacil
• Microspheres
• Targeting