title: Formation of core-shell type biodegradable polymeric micelles from amphiphilic poly(aspartic acid)-block-polylactide diblock copolymer.
abstract: Poly(aspartic acid)-block-polylactide diblock copolymers (PAsp-b-PLAs) having both hydrophilic and hydrophobic segments of various lengths were synthesized. These PAsp-b-PLA diblock copolymers formed polymeric micelles consisting of a hydrophobic PLA core and a hydrophilic, pH-sensitive PAsp shell in aqueous solution. The effects of the segment length of both the PLA and the PAsp portions and the pH of the solution on the shapes and sizes of the PAsp-b-PLA polymeric micelles were investigated. The results indicated a balance between the effects of electrostatic repulsion, hydrogen bonding in the PAsp shell layer, and hydrophobic interactions in the PLA core determine the sizes of the PAsp-b-PLA polymeric micelles. Moreover, the PAsp-b-PLA polymeric micelles did not possess any cytotoxic activity against L929 fibroblast cells. The obtained polymeric micelle should be useful for biodegradable biomedical materials such as drug delivery vehicle.
authors.affiliation: Department of Applied Chemistry, Faculty of Engineering and High Technology Research Center, Kansai University, Suita, Osaka 564-8680, Japan.
authors.forename: Hidetoshi
authors.initials: H
authors.lastname: Arimura
authors.forename: Yuichi
authors.initials: Y
authors.lastname: Ohya
authors.forename: Tatsuro
authors.initials: T
authors.lastname: Ouchi
mesh_terms: D001672:Biocompatible Materials / Q000138:chemical synthesis* / Q000737:chemistry; D001673:Biodegradation, Environmental; D002460:Cell Line; D002470:Cell Survival / Q000187:drug effects; D006801:Humans; D006860:Hydrogen Bonding; D057927:Hydrophobic and Hydrophilic Interactions; D008823:Micelles; D018625:Microscopy, Atomic Force; D010455:Peptides; D011091:Polyesters; D011108:Polymers / Q000138:chemical synthesis* / Q000737:chemistry / Q000494:pharmacology; D055672:Static Electricity; D013501:Surface-Active Agents / Q000138:chemical synthesis
chemical_list: D001672:Biocompatible Materials; D008823:Micelles; D010455:Peptides; D011091:Polyesters; D011108:Polymers; D013501:Surface-Active Agents; C017645:polyaspartate; C033616:poly(lactide)