Abstract
The objective of this study was to achieve enhanced delivery of doxorubicin to the brain through transferrincoupled liposomes. Doxorubicin-loaded liposomes were prepared and characterized for particle size, shape, percent encapsulation efficiency and in vitro drug release. Doxorubicin was labeled with 99mTc-DTPA and optimized to achieve high labeling efficiency. The in vitro stability was determined to check the efficiency of the system to establish the suitability of the radiolabeled system for in vivo studies. 99mTc-DTPA labeled doxorubicin bearing noncoupled and coupled liposomes was administered intravenously and biodistribution studies were performed. The distribution of doxorubicin via noncoupled and coupled liposomes was determined in various organs (i.e. lungs, liver, kidneys, spleen and brain) by measuring radioactivity using a gamma scintillation unit. An average 7-fold increased brain uptake of the drug was observed after liposomal delivery of doxorubicin, while the transferrin-coupled liposomes increased approximately 10 fold brain uptake of doxorubicin. We conclude that transferrin-coupled liposomes can enhance the brain uptake of drugs like doxorubicin.
Keywords: Transferrin, liposome, doxorubicin, brain delivery