Design and evaluation of guar gum-based ofloxacin sustained release ocular insert

Abstract

To prepare ocular inserts of ofloxacin using guar gum as a polymer for sustained delivery over a period of 24 h.Ofloxacin ocular inserts were prepared by the solvent casting method using guar gum in different proportions (0.5% w/v, 0.75% w/v and 1.0% w/v). The prepared formulations were evaluated for thickness, weight variation, percentage drug content, surface pH, folding endurance, percentage moisture absorption and loss, percentage swelling, mechanical strength and in vitro transcorneal permeation. In vitro transcorneal permeation study was performed on goat cornea using a modified Franz diffusion cell. The inserts were found to be of uniform thickness (ranging from 51.230 ± 0.385 μm to 109.275 ± 0.522 μm) and weight (1.720 ± 0.079 mg to 3.402 ± 0.105 mg). The % drug content in the inserts was found to vary between 95.450 ± 0.427% and 98.471 ± 0.225.The cumulative % drug releases from the formulation ranged from 38.19 to 75.21 over a period of 24 h. All the formulations followed a zero order release pattern. The in vitro transcorneal study revealed that an increase in concentration of the polymer slowed down the release of ofloxacin from the formulation.Ocular inserts using guar gum as a polymer were successfully prepared and can be effectively used for sustained ocular delivery over a period of 24 h.