Mathematical evaluation of in vitro release profiles of hydroxypropylmethylcellulose matrix tablets containing carbamazepine associated to beta-cyclodextrin.

The release kinetics of carbamazepine (CBZ) either complexed or physically mixed with beta-cyclodextrin (betaCD) from hydroxypropylmethylcellulose (HPMC) matrix tablets was investigated using different mathematical equations. The model-dependent approach was compared to the utilization of fit factors. Notwithstanding difference (f1) and similarity (f2) factors allowed the differentiation of the formulations containing CBZ complexed with betaCD from the one containing a simple physical mixture of CBZ and betaCD. The Weibull model was more useful for comparing the release profiles. Weibull parameters were more sensitive to the differences between the two release kinetic data. Copyright 2004 Elsevier B.V.