Preparation and evaluation of nanoparticles for ocular delivery of diclofenac sodium

Abstract

Background and objective: Ocular drug delivery research is challenging due to the presence of anatomical and physiological barriers. The ophthalmic preparation of diclofenac sodium (DC) for relieving ocular inflammation is presently available in the market only as an eye drop solution with low ocular bioavailability. The goal of our study was to prepare and evaluate an eye drop formulation, containing a nanocarrier, chondroitin sulfate (CS)-chitosan (CH)-nanoparticles (NPs) (CS/ CH-NPs) is being evaluated for improving the bioavailability of diclofenac sodium into the eye. Methods: Formulation was developed and optimized for three different variables (chondroitin sulfate, chitosan, and initial drug concentration). The developed formula was evaluated by various in-vitro parameters such as particles' size, entrapment efficacy, zeta potential, and in vitro release profile. Results: The particles' size, entrapment efficacy, and zeta potential of the best formulation were found to be 251.1±15.12nm, 73.2±5.3%, and 38.89±5.05mV, respectively. Furthermore, the best formulation showed a biphasic release profile, initial burst release in the first hour, followed by sustained release within 24hours. Conclusion: Promising results of in-vitro studies indicated that CS-CH-NPs could be a potential substitute for improved ocular delivery of diclofenac sodium.