Nanoparticles for Drug and Gene Delivery in Treating Diseases of the Eye

Using biodegradable polymeric nanoparticles as model systems for drug and gene delivery, this chapter describes commonly used methods for preparing and characterizing nanoparticles. This chapter focuses on emulsion solvent evaporation-based methods for encapsulating hydrophilic as well as lipophilic drugs in polymeric nanoparticles. In order to describe methods for preparing nanoparticles, we have chosen poly(lactide) (PLA)/poly(lactide-co-glycolide) (PLGA) as the carrier materials for nanoparticles intended for drug and gene delivery. Nanoparticles intended for drug and gene delivery can be characterized for various parameters including particle size, size distribution, morphology, zeta potential, drug loading, syringeability and injectability, in vitro drug release, and stability. Methods for the measurement of these parameters, which influence the performance characteristics of nanoparticles in vivo, are also discussed in this chapter.