PREPARATION, CHARACTERIZATION, IN VITRO EVALUATION OF PHYSOSTIGMINE-LOADED POLY(ORTHO ESTER) AND POLY(ORTHO ESTER) /PLGA BLEND SUB-MICRON SPHERES FABRICATED BY SPRAY DRYING

摘要

Physostigmine-loaded poly(ortho ester) (POE) and POE/PLGA blend sub-micron spheres was fabricated by spray drying for the prevention against organophosphate poisoning and the treatment of Alzheimer's disease. POE yielded well-dispersed sub-micron spheres that provided a sustained release of physostigmine. However, PLGA sub-micron spheres were aggregated. The physostigmine release from the PLGA sub-micron spheres was characterized by a high initial burst release. Interestingly, when the weight ratio of POE to PLGA was higher than 1:1, the sub-micron spheres were coated with POE and physostigmine release was slower than that from the PLGA sub-micron spheres due to the hydrophobicity of POE.