Formulation and characterization of a novel pH-triggered in-situ gelling ocular system containing Gatifloxacin

The present research work deals with the formulation and evaluation of in-situ gelling system based on sol-to-gel transition for ophthalmic delivery of an antibacterial agent gatifloxacin, to overcome the problems of poor bioavailability and therapeutic response exhibited by conventional formulations based a sol-to-gel transition in the cul-de-sac upon instillation. Carbopol 940 was used as the gelling agent in combination with HPMC and HPMC K15M which acted as a viscosity enhancing agent. The prepared formulations were evaluated for pH, clarity, drug content, gelling capacity, bioadhesive strength and in-vitro drug release. In-vitro drug release data of optimized formulation (F12) was treated according to Zero, First, Korsmeyer Peppas and Higuchi kinetics to access the mechanism of drug release. The clarity, pH, viscosity and drug content of the developed formulations were found in range 6.0-6.8, 10-570cps, 82-98% respectively. The gel provided sustained drug release over an 8 hour period. The developed formulation can be used as an in-situ gelling vehicle to enhance ocular bioavailability and the reduction in the frequency of instillation thereby resulting in better patient compliance. Key Words: In-situ gelation; Gatifloxacin; Carbopol 940; HPMC K15M. DOI: http://dx.doi.org/10.3329/icpj.v1i3.9661 International Current Pharmaceutical Journal 2012, 1(3): 43-49