title: Surface hydrophobicity of particles is not necessarily the most important determinant in their in vivo disposition after intravenous administration in rats.
abstract: The in vivo disposition of polystyrene microsphere (MS) with the particle size of 50 nm (MS-50) and lecithin-coated MS-50 (LMS-50) after intravenous administration to rats was characterized. While a rapid elimination from the systemic circulation was observed for MS-50, much more prolonged circulating property was observed for LMS-50. In addition, this in vivo disposition property of LMS-50 was suggested to be ascribed to its lower affinity to the liver, which is the determining organ of the in vivo disposition of MS-50. The evaluation of surface hydrophobicity of MS-50 and LMS-50 in buffer solution revealed that the surface of MS-50 is more hydrophobic than that of LMS-50. However, LMS-50 was oppositely found to be more hydrophobic than that of MS-50 in rat serum. The profiles of serum proteins associated with MS-50 and LMS-50 were also examined by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE). The results showed that the amounts of some adsorbed proteins are greatly different between MS-50 and LMS-50. From these findings, it was suggested that the substantial difference in the in vivo disposition between MS-50 and LMS-50 would not be attributed to the difference in their surface hydrophobicity in the blood, but the difference in the type of serum proteins associated with them.
authors.affiliation: Department of Pharmaceutics, Faculty of Pharmaceutical Sciences, Okayama University, 700-8530, Okayama, Japan.
authors.forename: K
authors.initials: K
authors.lastname: Ogawara
authors.forename: K
authors.initials: K
authors.lastname: Furumoto
authors.forename: Y
authors.initials: Y
authors.lastname: Takakura
authors.forename: M
authors.initials: M
authors.lastname: Hashida
authors.forename: K
authors.initials: K
authors.lastname: Higaki
authors.forename: T
authors.initials: T
authors.lastname: Kimura
mesh_terms: D000818:Animals; D001798:Blood Proteins / Q000378:metabolism; D057927:Hydrophobic and Hydrophilic Interactions; D007275:Injections, Intravenous; D008297:Male; D008863:Microspheres; D010316:Particle Size; D010713:Phosphatidylcholines / Q000097:blood / Q000493:pharmacokinetics; D011137:Polystyrenes / Q000097:blood / Q000493:pharmacokinetics; D051381:Rats; D017208:Rats, Wistar; D013499:Surface Properties; D014018:Tissue Distribution / Q000502:physiology
chemical_list: D001798:Blood Proteins; D010713:Phosphatidylcholines; D011137:Polystyrenes