title: [Preparation of docetaxel-loaded pH-sensitive block copolymer micelles].
abstract: Basing on the synthesis of pH-sensitive amphiphilic block copolymer poly (2-ethyl-2-oxazoline)-poly (D, L-lactide)(PEOz-PDLLA), this paper presents the preparation of docetaxel-loaded pH-sensitive block copolymer micelles using film dispersion method. The critical micelle concentration (CMC) was measured by pyrene fluorescent probe technique. The entrapment efficiency and drug-loaded amount were determined by HPLC. The morphology, diameter and surface potential of the micelles were characterized by transmission electron microscopy (TEM), dynamic light scattering (DLS) and zeta potential analyzer, respectively. The in vitro release behavior of DTX from polymeric micelles was investigated using dialysis method. The results indicated that the CMC, drug-loaded amount and entrapment efficiency of the micelles was 1.0 x 10(-3) g x L(-1), 15.0% and 91.1%, respectively. The micelles had a narrow size distribution, with a mean diameter of 28.7 nm. The micelle was globular-shaped and its zeta potential was (1.19 +/- 0.12) mV. In pH 7.4 PBS, docetaxel was released in a sustained manner from the micelles; while in PBS at pH 5.0, drug was released more rapidly, which suggested the pH-sensitive drug release behavior of the PEOz-PDLLA micelles. According to all the studies above, it can be concluded that the PEOz-PDLLA block copolymer micelles may be applied as promising drug delivery system for hydrophobic anti-tumor drugs.
authors.affiliation: School of Pharmaceutical Sciences, Shenyang Pharmaceutical University, Shenyang 110016, China. chendawei@syphu.edu.cn
authors.forename: Da-wei
authors.initials: DW
authors.lastname: Chen
authors.forename: Lu
authors.initials: L
authors.lastname: Yan
authors.forename: Ming-xi
authors.initials: MX
authors.lastname: Qiao
authors.forename: Hai-yang
authors.initials: HY
authors.lastname: Hu
authors.forename: Xiu-li
authors.initials: XL
authors.lastname: Zhao
authors.forename: Xi
authors.initials: X
authors.lastname: Chen
authors.forename: Yi-hui
authors.initials: YH
authors.lastname: Deng
mesh_terms: D000970:Antineoplastic Agents / Q000008:administration & dosage / Q000378:metabolism; D000077143:Docetaxel; D004337:Drug Carriers; D004339:Drug Compounding; D016503:Drug Delivery Systems; D006863:Hydrogen-Ion Concentration; D008823:Micelles; D010080:Oxazoles / Q000737:chemistry; D010316:Particle Size; D011073:Polyamines; D011091:Polyesters / Q000737:chemistry; D011108:Polymers / Q000737:chemistry; D043823:Taxoids / Q000008:administration & dosage* / Q000378:metabolism
chemical_list: D000970:Antineoplastic Agents; D004337:Drug Carriers; D008823:Micelles; D010080:Oxazoles; D011073:Polyamines; D011091:Polyesters; D011108:Polymers; D043823:Taxoids; C511916:poly(2-ethyl-2-oxazoline); D000077143:Docetaxel; C033616:poly(lactide)