| 초록 |
Biodegradable polymers have become increasingly important in the development of drug delivery systems. In this work, biodegradable poly(l-lactide) (PLA)/poly(ethylene glycol) (PEG) microcapsules are investigated in the degradation, size distribution, and drug release behavior. The degradation of PLA/PEG is much faster than that PLA, that is, the mass of PLA recovered in 3 week is 70.0%, whereas the degradations of PLA/PEG containing 5 and 10 wt% PEG are 51.8% and 39.1%, respectively. Such a result is comprehensible from the viewpoint that PLA/PEG is more hydrophilic, due to a relatively carboxylic acid end group of PEG. The particle size of the PLA microcapsules is smaller than that made from PLA/PEG copolymers under the same conditions, due to the swelling characteristics of the ethylene glycol. Drug release from microcapsules is effected by the properties of PLA/PEG copolymers determined by UV/Vis. spectra. It is found that the drug release rates of the microcapsules are significantly increased with adding of PEG, which is explained by higher hydration rate and swelling characteristics of the ethylene glycol. |
