Role of Aminated derivatives of Natural Gum in Release Modulating Matrix Systems of Losartan Potassium: Optimization of Formulation using Box-Behnken Design

The aim of the present research work was to systemically device a model of factors that would yield an optimized release modulating dosage form of an anti-hypertensive agent, losartan potassium, using response surface methodology by employing a 3-factor, 3-level Box-Behnken statistical design. Independent variables studied were the amount of the release retardant polymers – aminated fenugreek gum (X1), aminated tamarind gum (X2) and aminated xanthan gum (X3). The dependent variables were the burst release in 15 min (Y1), cumulative percentage release of drug after 60 min (Y2) and hardness (Y3) of the tablets with constraints on the Y2 = 31–35%. Statistical validity of the polynomials was established. In vitro release and swelling studies were carried out for the optimized formulation and the data were fitted to kinetic equations. The polynomial mathematical relationship obtained Y2=32.91-2.29X1-5.68X2-0.97X3+0.20X1X3-0.005X2X3-0.92X12-1.89X22 explained the main and quadratic effects, and the interactions of factors influencing the drug release from matrix tablets. The adjusted (0.9842) and predicted values (0.9600) of r2 for Y2 were in close agreement. Validation of the optimization study indicated high degree of prognostic ability of response surface methodology. The Box-Behnken experimental design facilitated the formulation and optimization of release modulating matrix systems of losartan potassium.