Emulsion spray-drying for the preparation of albumin-loaded PLGA microspheres

The purpose of this work was to study the encapsulation of bovine serum alb umin (BSA) in polylactide-co-glycolide (PLGA) microspheres using an emulsio n/spray-drying method. Albumin was dissolved in an aqueous phase (w) in the presence of surfactant and emulsified in an organic phase containing the p olymer (o). To stabilize the emulsion, different types of surfactant (Pluro nic(R) F68, Pluronic F127, sodium oleate, dioctylsufosuccinate) were added to the aqueous phase. The w/o emulsion was spray-dried to obtain BSA-loaded PLGA microspheres. The effect of type of surfactant on microsphere charact eristics was evaluated. The microspheres were characterized for their morph ology by scanning electron microscopy (SEM) and granulometric analysis; dru g content determination and in vitro dissolution tests were performed. Resu lts showed that the emulsion/spray-drying method is suitable for obtaining small microparticles (2-5 mum) characterized by high drug payloads (70%-80% encapsulation efficiency). The type of surfactant affects the microsphere shape and BSA release behavior.