Preparation of ibuprofen/sPEG-b-PLLA copolymer microspheres and its in vitro release properties.
- Author:
Ya-ling LIN
1
;
An-qiang ZHANG
;
Fu-yi GUAN
;
Yao-dong CHEN
;
Wei-an TAN
;
Lian-shi WANG
Author Information
1. Department of Pharmaceutical Engineering, College of Resources and Environment, South China Agriculture University, Guangzhou 510642, China. linyaling@scau.edu.cn
- Publication Type:Journal Article
- MeSH:
Analgesics, Non-Narcotic;
administration & dosage;
chemistry;
Anti-Inflammatory Agents, Non-Steroidal;
administration & dosage;
chemistry;
Delayed-Action Preparations;
Drug Carriers;
Ibuprofen;
administration & dosage;
chemistry;
Lactates;
chemistry;
Lactic Acid;
chemistry;
Magnetic Resonance Spectroscopy;
Microspheres;
Particle Size;
Polyesters;
Polyethylene Glycols;
chemistry;
Polymers;
chemistry;
Spectroscopy, Fourier Transform Infrared
- From:
Acta Pharmaceutica Sinica
2010;45(12):1570-1575
- CountryChina
- Language:Chinese
-
Abstract:
Biodegradable four-arm star-shaped poly(ethylene glycol)-block-poly(L-lactic acid) copolymer (sPEG-b-PLLA), four-arm star-shaped poly(L-lactic acid) (sPLLA), linearly poly(ethylene glycol)-block-poly(L-lactic acid) copolymer (PEG-b-PLLA) and linearly poly(L-lactic acid) (PLLA) were synthesized from L-lactice acid, pentaerythritol, poly(ethylene glycol) and star-shaped poly(ethylene glycol), using the method of melt polycondensation, and the products were characterized and confirmed by 1H NMR spectroscopy, FT-IR and GPC. Four types of ibuprofen loaded microspheres based on the above four types of polymers, i.e., IBU/PLLA, IBU/sPLLA, IBU/PEG-b-PLLA, and IBU/sPEG-b-PLLA microspheres were prepared using the method of solvent evaporation, and the optimized preparation technology was obtained via orthogonal experiments, and the drug-encapsulating properties and in vitro drug-releasing properties were studied. The results showed that compared with IBU/PLLA and IBU/PEG-b-PLLA microspheres, the drug encapsulate efficiency of IBU/sPLLA and IBU/sPEG-b-PLLA microspheres were higher and the in vitro drug releasing rate slowed down, which mainly due to the faster degradation of sPLLA and sPEG-b-PLLA for the star-shaped structure and the block copolymerization of sPEG. The drug releasing curves of these three types of microspheres could be fit by first-order equation, and the releasing mechanism was non-Fickian diffusing, i.e., the synergetic effect of polymer degradation and drug diffusion.