DESIGN AND EVALUATION OF A TEMPERATURE RESPONSIVE IN SITU GELLING OPHTHALMIC DRUG DELIVERY SYSTEM CONTAINING BERBERINE HCL

Objective: In this study, the efficacy of an in situ gelling formulation developed by combining polymers sensitive to different physiological stimuli for ophthalmic drug delivery systems was investigated. As the active pharmaceutical ingredient, berberine hydrochloride was selected. The primary aim of the study was to design an innovative ophthalmic drug delivery system that offers ease of administration, improves therapeutic efficacy by increasing retention on the ocular surface, and enhances patient compliance by reducing the frequency of dosing. Material and Method: The formulation was prepared using Pluronic F127, chitosan, and κ-carrageenan polymers. Pluronic F127 and chitosan solutions were prepared by the cold method, while the κ-carrageenan solution was prepared at 50°C. The developed system was evaluated in terms of clarity, pH, and gelation temperature. Based on the results obtained, Berberine HCl was added at a concentration of 0.26 mg/ml, in accordance with literature data, to the formulation that exhibited optimal characteristics. The drug release profile was evaluated at 35°C in pH 7.4 isotonic phosphate buffer using the dialysis membrane method. For the stability studies, the formulations were stored for one month at 25 ± 2°C / 60 ± 5% relative humidity and 5 ± 3°C. At the end of the storage period, all analyses were repeated and the drug release profiles were compared using difference (f₁) and similarity (f₂) factors. Result and Discussion: In this study, an in situ gelling ophthalmic drug delivery system containing berberine HCl was developed using a triple polymer system. The results suggest that this system, which may enhance patient compliance, could be a potential alternative to conventional eye drops; however, this needs to be supported by in vivo studies.