title: Study on drug release behaviors of poly-alpha,beta-[n-(2-hydroxyethyl)-L-aspartamide]-g-poly(epsilon-caprolactone) nano- and microparticles.
abstract: Biodegradable amphiphilic graft copolymers poly-alpha,beta-[N-(2-hydroxyethyl)-L-aspartamide]-g-poly(epsilon-caprolactone) (PHEA-g-PCL) with different branch lengths were synthesized through the ring-opening polymerization of epsilon-caprolactone initiated by the macroinitiator PHEA bearing hydroxyl groups. With use of the graft copolymers with different compositions, nanoparticle drug delivery systems with sizes smaller than 100 nm were prepared by a dialysis method, and microparticle drug delivery systems with sizes smaller than 5 microm were fabricated by a melting-emulsion method. The regularly spherical shapes of the drug-loaded nano- and microparticles were verified by transmission electron microscopy and scanning electron microscopy. In vitro drug release properties of nano- and microparticle drug delivery systems were investigated, with the emphasis on the effects of polymer composition, particle size, and drug-loading content on the release behaviors.
authors.affiliation: Key Laboratory of Biomedical Polymers of Ministry of Education, Department of Chemistry, Wuhan University, Wuhan 430072, PR China.
authors.forename: Zhi-Mei
authors.initials: ZM
authors.lastname: Miao
authors.forename: Si-Xue
authors.initials: SX
authors.lastname: Cheng
authors.forename: Xian-Zheng
authors.initials: XZ
authors.lastname: Zhang
authors.forename: Ren-Xi
authors.initials: RX
authors.lastname: Zhuo
mesh_terms: D003956:Dialysis; D016503:Drug Delivery Systems; D007783:Lactones / Q000138:chemical synthesis* / Q000737:chemistry*; D015394:Molecular Structure; D049329:Nanostructures / Q000737:chemistry*; D010316:Particle Size; D011108:Polymers / Q000138:chemical synthesis* / Q000737:chemistry*; D013997:Time Factors
chemical_list: D007783:Lactones; D011108:Polymers; C507591:poly-alpha,beta-(N-(2-hydroxyethyl)-L-aspartamide)-g-poly(epsilon-caprolactone)