Size Homogeneity of a Liposome Preparation is Crucial for Liposome Biodistribution in Vivo

Abstract

Small liposomes, prepared by sonication or extrusion, were compared for their biodistribution patterns in mice. Significant difference was observed for a given lipid composition for liposomes prepared by these two different methods. Using gel filtration, negative stain EM, and quasi-elastic light scattering analysis of the liposome preparations, it appeared that such difference was resulted from the heterogeneity in liposome size. Sonicated liposomes, more heterogeneous in size, generally showed a lower uptake in the liver and spleen and higher level in the blood than the less heterogeneous extruded liposomes.