title: Comparative studies of polyethylene glycol-modified liposomes prepared using different PEG-modification methods.
abstract: To address the issue of excess polyethylene glycol (PEG)-lipid degradation observed when PEG-modified liposomes are prepared using the pH-gradient method, a concept using a novel PEG-modification method, called the post-modification method, was proposed and evaluated. To assess the proof concept, a preservation-stability study and a pharmacokinetic study were performed that compared the conventional PEG-modification method, called the pre-modification method, with the post-modification method. The results show that PEG-lipid degradation could be markedly inhibited in the post-modification method. Furthermore, the post-modification method could be used without any manufacturing process difficulties, especially with high PEG-lipid content. In addition, a higher blood circulation capability was observed in the post-modification method. Through comparative studies, it was found that the post-modification method was advantageous compared to the pre-modification method. In conclusion, the post-modification method has the potential to be a novel PEG-modification method that can achieve a higher preservation stability of PEG-lipid, a greater ease of manufacturing, and a higher blood circulation capability, especially in the manufacturing of pH-gradient liposomal products.
authors: Terumo Cororation, Kanagawa, Japan.
authors: Koji
authors: K
authors: Nakamura
authors: Keiko
authors: K
authors: Yamashita
authors: Yuki
authors: Y
authors: Itoh
authors: Keisuke
authors: K
authors: Yoshino
authors: Shigenori
authors: S
authors: Nozawa
authors: Hiroaki
authors: H
authors: Kasukawa
mesh_terms: D000818:Animals; D008081:Liposomes; D008297:Male; D011092:Polyethylene Glycols / Q000737:chemistry* / Q000493:pharmacokinetics; D051381:Rats; D017207:Rats, Sprague-Dawley
chemical_list: D008081:Liposomes; D011092:Polyethylene Glycols