Preparation Of Uniform-Sized Microcapsules Loading Bio-Drugs By Combining Membrane Emulsification And Multiple Emulsion-Solvent Evaporation

Microcapsules of biodegradable polymers such as poly (DL-lactic acid, PLA) and poly (DL-lactic-co-glycolic acid, PLGA) have received much attention due to their ability to controll the release of bioactive macromolecules, such as some therapeutic peptides or proteins. The objectives of this thesis are to develop a novel membrane emulsification technique, combined with W/O/W double emulsion method, to prepare uniform-sized bio-drugs loaded microcapsules with high drug encapsulation efficiency, high bioactivity preservation, and stable drug release behavior, as well as to investigate the effects of process parameters on the characteristics of microcapsules.First, by choosing Arlacel 83 as the oil-soluble emulsifier, and dichloromethane/toluene(1.0g/ml) as mixture solvent to adjust the density of the oil phase to the same as the water phase, the stability of W₁/O primary emulsion could exceed 24h. Then, lysozyme was successfully encapsulated into the PLA microcapsules prepared by membrane emulsification technique.