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Paper text:
the variables studied were concentration of diluents ( pullulan , x1 ) , superdisintigrant ( sodium starch glycolate , x2 ) , and direct compression aid ( spray dried lactose , x3 ) .
tablets were prepared by direct compression methods on rotary tablet press using flat plain- face punches .
tablets were characterized for weight variation , thickness , disintegration time ( y1 ) and hardness ( y2 ) .
disintegration time was strongly affected by quadratic terms of pullulan , sodium starch glycolate and spray dried lactose .
the positive value of regression coefficient for pullulan suggested that hardness increased with increased amount of pullulan .
in general , disintegration of tablets has been reported to slow down with increase in hardness . however , in present study higher concentration of pullulan was found to improve tablet hardness without increasing the disintegration time .
thus , pullulan is proposed as suitable diluents to archive fast disintegrating tablets with sufficient hardness .
in the present study it can be concluded that good correlation was obtained between the predicted values and experimental data of the optimized formulation methodology in optimizing fast disintegrating tablets using pullulan as a diluent .
it was also observed that further increase the concentration of pullulan ( diluents ) increases the hardness without affecting disintegration time.[15 ]
the objective of this work was to apply central composite experimental design to investigate main and interaction effect of formulation parameters in optimizing novel fast disintegration tablets formulation using pullulan as diluents . 
 face centered central composite experimental design was employed to optimize fast disintegration tablet formulation . 
 the variables studied were concentration of diluents ( pullulan , x1 ) , superdisintigrant ( sodium starch glycolate , x2 ) , and direct compression aid ( spray dried lactose , x3 ) . 
 tablets were characterized for weight variation , thickness , disintegration time ( y1 ) and hardness ( y2 ) . 
 good correlation between the predicted values and experimental data of the optimized formulation methodology in optimizing fast disintegrating tablets using pullulan as a diluent .