Full Factorial Design in Formulation of Lamotrigine Suspension using Locust Bean GumAuthor(s): A. Prameela Rani and Hema Veesam
Lamotrigine, a weakly basic, anticonvulsant drug have high permeability but poor solubility belonging to BCS Class II. The aim of this work was to formulate suspension in order to improve the bioavailability and patient compliance. In the present investigation, a perfect suspension was made using Locust bean gum, sodium alginate as viscosity enhancers and sodium citrate as anti-flocculant. Using 2 level 3 factor full factorial design, amount of ingredients were selected as independent variables while viscosity and sedimentation volume as response or dependent variables. The responses of data were recorded and analyzed for ANOVA, the individual parameters were evaluated by polynomial equation for each response generated using multiple linear regression analysis. The relationship between dependent and independent variables was further elucidated using contour plots finally optimized for desired response. From the results the eight formulations were made by factorial design, later optimized batch was prepared after desirability analysis and validated the obtained value with predicted showing good reliability of the design, highest r2 and lowest sum of squares of residual was observed for the responses. Thus the prepared suspension showed high sedimentation volume, high redispersibility and optimum viscosity following non-Newtonian type behavior.