title: Biodistribution characteristics of amino acid dendrimers and their PEGylated derivatives after intravenous administration.
abstract: In this study, we synthesized dendritic poly(L-lysine)s (DPKs), dendritic poly(L-ornithine)s (DPOs), which are constructed as novel amino acid dendrimers, and PEGylated KG6 (the sixth generation of DPKs), and evaluated the physicochemical properties and biodistribution characteristics of these dendrimers. The particle size of DPKs and DPOs was well controlled in the nanometer range. The zeta-potential of these dendrimers was slightly positive and this gradually increased in association with their generation. After intravenous administration to mice, all tested dendrimers cleared rapidly from blood flow and mainly accumulated in the liver and kidney. The hepatic and renal accumulation changed in a generation-dependent manner. In contrast, no significant distributional differences between same generation of DPK and DPO were observed, although the constituent amino acids, particle size, and zeta-potential were different. However, PEGylation of KG6 caused great changes in particle size, zeta-potential, blood retention and organ distribution in vivo, indicating that the PEGylation is applicable strategy to improve biodistribution characteristics of dendrimeric molecules. The information provided by this study will be helpful for the development of future drug delivery systems using amino acid dendrimers as safe drug carriers.
authors.affiliation: Department of Drug Delivery Research, Graduate School of Pharmaceutical Sciences, Kyoto University, 46-29 Yoshida-Shimo-Adachi-cho, Sakyo-ku, Kyoto 606-8501, Japan.
authors.forename: Tatsuya
authors.initials: T
authors.lastname: Okuda
authors.forename: Shigeru
authors.initials: S
authors.lastname: Kawakami
authors.forename: Tadahiro
authors.initials: T
authors.lastname: Maeie
authors.forename: Takuro
authors.initials: T
authors.lastname: Niidome
authors.forename: Fumiyoshi
authors.initials: F
authors.lastname: Yamashita
authors.forename: Mitsuru
authors.initials: M
authors.lastname: Hashida
mesh_terms: D000410:Alanine Transaminase / Q000097:blood; D000596:Amino Acids / Q000737:chemistry*; D000818:Animals; D050091:Dendrimers / Q000008:administration & dosage / Q000737:chemistry / Q000493:pharmacokinetics*; D007275:Injections, Intravenous; D008297:Male; D051379:Mice; D008815:Mice, Inbred Strains; D008970:Molecular Weight; D010316:Particle Size; D010455:Peptides / Q000138:chemical synthesis / Q000737:chemistry; D011092:Polyethylene Glycols / Q000737:chemistry*; D011107:Polylysine / Q000138:chemical synthesis / Q000737:chemistry; D055672:Static Electricity; D013499:Surface Properties; D014018:Tissue Distribution
chemical_list: D000596:Amino Acids; D050091:Dendrimers; D010455:Peptides; C008973:polyornithine; D011107:Polylysine; D011092:Polyethylene Glycols; D000410:Alanine Transaminase