Acta Pharm. 59 (2009) 133-144


full paper

Original research paper


Preparation of pegylated nano-liposomal formulation containing SN-38: In vitro characterization and in vivo biodistribution in mice



1 Novel Drug Delivery Systems Laboratory, Faculty of Pharmacy, Tehran University of Medical Sciences, Tehran, PO Box 14155-6451, Islamic Republic of Iran

2 Medical Nanotechnology Research Centre, Tehran University of Medical Sciences, Tehran, PO Box 14155-6451, Islamic Republic of Iran

Accepted May 15, 2009


7-Ethyl-10-hydroxy-camptothecin (SN38), a metabolite of irinotecan HCl, is poorly soluble in aqueous solutions and practically insoluble in most physiologically compatible and pharmaceutically acceptable solvents. Formulation of SN38 in concentrated pharmaceutical delivery systems for parenteral administration is thus very difficult. Due to their biocompatibility and low toxicity, liposomes were considered for the delivery of SN38. In this study, pegylated liposomes with distearoylphosphatidylcholine, distearoylphosphatidylethanolamine containing SN38 were prepared and their characteristics, such as particle size, encapsulation efficiency, in vitro drug release and biodistribution, were investigated. The particle size of liposomes was in the range of 150-200 nm. The encapsulation efficiency and in vitro release rate of pegylated liposomes was higher than those of non-pegylated liposomes. As expected, the distribution of pegylated liposomes in body organs such as liver, kidney, spleen and lung was considerably lower than that of non-pegylated liposomes. Also, their blood concentration was at least 50 % higher than that of non-pegylated liposomes.


Keywords: nanoparticles, SN38, pegylated liposomes, PEG, biodistribution, drug delivery