PLGA microspheres and nanoparticles drug delivery for ocular diseases

Abstract

The use of biodegradable polymer microspheres and nanoparticles in topical form or for injection to the eye for treatment of ocular diseases such as glaucoma and age related macular degeneration is increasingly popular. One of the drugs used is Latanoprost for the treatment of glaucoma.

Attempts to encapsulate latanoprost in poly(DL-lactide-co-glycolide) microspheres by spray drying in our laboratories was only able to achieve a drug release for three days. Therefore this study aims to fabricate PLGA nanoparticles using nanoprecipitation and modified spontaneous emulsification solvent diffusion (SESD) method and also PLGA microspheres using solvent evaporation method to achieve a longer drug release profile.

However we have failed to replicate PLGA nanoparticles using the above methods, though we managed to fabricate PLGA microspheres successfully. The PLGA microspheres were then loaded with latanoprost and compared with spray dried PLGA microspheres in terms of BET surface area, porosities, drug loading profiles and also analysis under SEM.

After comparisons, PLGA microspheres made by solvent evaporation method shows no agglomeration, however BET surface area decreases and porosities increases. However, drug loading profiles were similar to that of spray dried PLGA microspheres achieving a drug release profile of only 50 hours. Therefore further work is required to increase period of drug release for the PLGA microspheres made using this method.