Versatile kinetic-approach to analysis of dissolution data

A new kinetically based dissolution equation is presented that considers dissolution of polydisperse systems and disintegrating solid dosage forms. The equation is applicable under sink as well as nonsink conditions and enables the specific dissolution rate parameter, the dispersion parameter, the disintegration lag time, and a newly introduced parameter, the dissolution availability, to be evaluated simultaneously and directly from percent of label claim dissolved versus time data. The equation showed excellent fit to dissolution data for aminophylline tablets. The kinetic significance of the estimated parameters of the equation is discussed. The method of analysis is compared to an approach employing an empirical equation based on a modified Weibull distribution function.