Abstract

PREPARATION AND EVALUATION OF pH AND TEMPERATURE SENSITIVE POLYMER BASED IN-SITU GEL FOR OCULAR DELIVERY

Kunal Arora and Sumita Singh*

ABSTRACT

The most frequently used ophthalmic dosage forms i.e. ophthalmic solutions and suspensions are compromised in their effectiveness by several limitations, leading to poor ocular bioavailability. In situ hydrogels are instilled as drops in the eye and undergoes a sol to gel transition in the cul-de-sac, improving ocular bioavailability by increasing the duration of contact with corneal tissue, thereby reducing the frequency of administration. In this study, an ophthalmic drug delivery system was developed using two different gelling agents with different mechanisms for in situ gelation of Acyclovir, an antiviral drug. Sodium alginate was used as an ion sensitive and Poloxamer as a temperature sensitive gelling agent. HPMC K4M was employed as viscofying agent. The formulations F1 to F3 and F4 to F6 were evaluated for Appearance/Clarity, pH, drug content, in vitro gelation, rheological studies, in-vitro drug release and bioadhesion test. The results were found to be satisfactory in terms of appearance/clarity, pH, gelation capacity and rheological properties. The different polymer combination showed a positive effect on bioadhesion force and was also found helpful in sustained release rate of the drug.

Keywords: ophthalmic hydrogel, In-situ, Acyclovir, Poloxamer, Sodium Alginate.