Surface-modified PLGA nanoparticles for ocular use: in vitro and in vivo evaluations

This study is concerned with preparing nanoparticulate system as an ophthalmic delivery system for fluocinolone acetonide to improve its ocular bioavailability using a simple yet attractive method. Thin film hydration method... [ view full abstract ]

This study is concerned with preparing nanoparticulate system as an ophthalmic delivery system for fluocinolone acetonide to improve its ocular bioavailability using a simple yet attractive method. Thin film hydration method was used to prepare poly(lactic-co-glycolic acid) (PLGA) nanoparticles. Two different types of PLGA was used (75/25 and 50/50 copolymer molar ratio of DL-lactide/glycolide). Results demonstrated that using PLGA with lower glycolic acid monomer ratio exhibited high values for particle size (PS), zeta potential (ZP) and drug encapsulation efficiency (EE) along with slow drug release pattern. Moreover, increasing the drug concentration during nanoparticles preparation enhanced its EE to reach almost 100%. Surface modification of optimized formulation was done using different amount of stearylamine and chitosan HCl aiming at increasing nanoparticles mucoadhesion ability. PLGA nanoparticles coated with 0.1% w/v chitosan HCl attained most suitable results of PS, ZP and EE values as well as high drug release properties. Transmission electron microphotographs illustrated the deposition of chitosan molecules on the nanoparticles surfaces. In-vivo study was performed on Albino rabbit’s eyes and pharmacokinetic studies revealed that the prepared novel chitosan-coated PLGA nanoparticles showed rapid and extended drug delivery to the eye.