Formulation and Evaluation of Polymeric and Ophthalmic Drug Delivery Systems

Abstract

In the current project Moxifloxacin hydrochloride in situ gels for ophthalmic use were prepared utilizing a multistimuli approach, i.e. combination of stimuli sensitive polymersviz .Carbopol (pH sensitive), Pluronic (temperature sensitive) and Gellan gum (ion sensitive). Formulation optimization was done by using Box Behnken design (Design expert 10 software) for assessing the effect of polymer concentration on product characteristics viz. viscosity, gelation capacity, and mean release time (MRT). Thirteen combinations with varying concentration of the polymers were prepared and tested to optimize the formula. Finally three batches OF1, OF2, OF3 of optimized formulation were prepared and evaluated. All the three batches were satisfactory in visual appearance, clarity and exhibited instantaneous in-situgelation. The percentage drug content was found to be 97.50±0.55, 98.29±0.43 and 97.83±0.20 respectively. The viscosity valuesexhibitedalmost ten folds increase under physiological conditions. Formulation OF2 exhibited a maximum in-vitrodrug release of 94.9±1.06% over an 8hrs period. The preparations were isotonic with blood and exhibited significant antimicrobial activity against Pseudomonas aueroginosaand Staphylococcus aureus. Ex-vivopermeation studies and bioadhesion studies carried out using goat cornea implied that the formulation was good enough to be retained on the corneal surface for desired local action during ocular infections.Ocular irritancy test (HET-CAM) and histopathological studies ascertained the biocompatibility of the formulation. The formulated in situgel was able to show its efficacy, non irritability and stability. The drug release was sustained for 8 hours, hence can be proposed to be effective substitutes for eye drops. newline newline