title: Microspheres made by w/o/o emulsion method with reduced initial burst for long-term delivery of endostar, a novel recombinant human endostatin.
abstract: The purpose of this work is to design biodegradable Poly(lactide-co-glycolide) (PLGA) microspheres with low initial burst for sustained delivery of Endostar (a novel recombinant human endostatin) and investigate effects of PLGA molecular weight and composition on the release behavior of Endostar microspheres. Endostar microspheres were prepared by using novel w/o/o multiple emulsification-evaporation technique. Effects of polymer molecular weight and copolymer composition on particle properties and release behavior (in vitro and in vivo) have been reported. Drug release in vitro decreased with increase in molecular weight and lactide content of PLGA. Zero order release and low initial burst were obtained with all microsphere formulations. The in vivo performance of Endostar microspheres were also found to be dependent on the polymer molecular weight and copolymer composition. Together, these results suggest that the initial burst release can be reduced by w/o/o emulsion method and the release of Endostar can be changed significantly by varying the polymer molecular weight and copolymer composition.
authors.affiliation: State Key Laboratory of Pharmaceutical Biotechnology, Nanjing University, Nanjing 210093, China.
authors.forename: Jinhui
authors.initials: J
authors.lastname: Wu
authors.forename: Lin
authors.initials: L
authors.lastname: Wu
authors.forename: Xiaoqiang
authors.initials: X
authors.lastname: Xu
authors.forename: Xiangyang
authors.initials: X
authors.lastname: Xu
authors.forename: Xiaojin
authors.initials: X
authors.lastname: Yin
authors.forename: Yingjie
authors.initials: Y
authors.lastname: Chen
authors.forename: Yiqiao
authors.initials: Y
authors.lastname: Hu
mesh_terms: D020533:Angiogenesis Inhibitors / Q000008:administration & dosage* / Q000097:blood / Q000378:metabolism / Q000494:pharmacology*; D000818:Animals; D002465:Cell Movement / Q000187:drug effects; D002478:Cells, Cultured; D016503:Drug Delivery Systems / Q000379:methods*; D004655:Emulsions / Q000737:chemistry; D043169:Endostatins / Q000008:administration & dosage* / Q000097:blood / Q000378:metabolism / Q000494:pharmacology*; D042783:Endothelial Cells; D006801:Humans; D008863:Microspheres; D011098:Polyglactin 910 / Q000737:chemistry; D051381:Rats; D017207:Rats, Sprague-Dawley; D011994:Recombinant Proteins / Q000008:administration & dosage / Q000097:blood / Q000378:metabolism / Q000494:pharmacology
chemical_list: D020533:Angiogenesis Inhibitors; D004655:Emulsions; D043169:Endostatins; D011994:Recombinant Proteins; D011098:Polyglactin 910