DESIGN, DEVELOPMENT AND OPTIMIZATION OF VALSARTAN LIQUISOLID TABLETS USING BOX-BEHNKEN DESIGN

The aim of the present study was to investigate the applicability of liquisolid technique in improving the dissolution properties of  Valsartan in a solid dosage form. This study was designed to optimize and evaluate the effects of different formulation variables: amount of liquid vehicle (X₁), ratio of carrier to coating material(X₂) and amount of magnesium oxide(X₃) on angle of repose (Y₁), hardness(Y₂) and in-vitro release(Y₃) of formulation using three level three factor Box-Behnken statistical design. The non-linear quadratic model generated by the design is of the form: Y = A₀ + A₁X₁ + A₂X₂ + A₃X₃ + A₄X₁X₂ + A₅X₂X₃ + A₆X₁X₃ + A₇X₁² + A₈X₂² +A₉X₃² + E, where Y is the measured response associated with each factor level combination. Contour and response surface plots were depicted based on the equation given by the model. The optimization procedure generated the maximum overall desirability value. The optimized formula yields observed values close to the predicted values. Furthermore, the commonly used carrier and coating materials in liquisolid systems Avicel^® and Aerosil^® were replaced by Neusilin^®, an amorphous magnesium aluminometasilicate with an extremely high specific surface area of 339 m²/g to improve the efficiency of liquisolid approach.