| In this dissertation, the synthesis of poly (lactic acid) was the first issue, then poly (lactic acid)(PLA) and poly (lactide-co-glycolide)(PLGA) microspheres were prepared by the solvent evaporation method, and the release properties of microspheres are researched.The first important part of this dissertation is the synthesis of poly (lactic acid) with D, L-lactic acid as starting materials. First, D, L-lactic acid was used to synthesize the monomer lactide at a high temperature and vacuum. Purified lactide and stannous octoate was used to prepare poly (lactic acid) at the proportion of1:0.5%.The polymerization of PLA was carried at160℃and in the high vacuum, followed by purification in methanol. The consequence of Infrared spectrophotometry and NMR interpreted that PLA was successfully synthesized. The above compound was characterized by Infrared spectrophotometry and NMR, which indicated that the preparation was successful.The second part of this dissertation is the preparation of microspheres. The microspheres without drug were prepared using o/w emulsion solvent evaporation method. First, the influence factors in the progress of preparing PLA and PLGA microspheres were studied according to monofactor method. The microspheres prepared by the optimum preparation method were smooth, regular in morphology, good decentralization, and the average particle size was with narrow size distribution. The characteristic of CBZ-MS (carbamazepine-loaded microspheres) was also researched. The result showed that the mean diameters of the CBZ-MS were convergence. The drug loading were2.3%and11.38%respectively.In vitro release of CBZ from microspheres was performed by oscillating in constant temperature. The release study indicated that the exhibited better sustained-release and the kinetics of CBZ PLA/PLGA microspheres in vitro release could be described by Higuchi equation.In conclusion, CBZ-MS prepared using biodegradable PLA exhibited good sustained-release capacity. |
PDF Full Text Request