Multivariate Analysis of Variance of Dissolution Data in the Development of Oral Sustained Release Formulations

A multivariate analysis of variance applied to polinomial interpretation of growth curves in used for the interpretation of dissolution curves of four experimental, sustained release, wax type theophylline tablets.

The factors under study were glyceril palmitic stearate, carboxypol imethylene contents and compression force. The tablets were formulated according an experimental design based on 4 × 4 Hadamard matrix. The USP type I apparatus for dissolution test and CHI 0.1 N plus O.1%. polysorbate 80 as dissolution medium was used.

The statistical interpretation of results showed: first, that dissolution rates were almost constant for the four formulations during 8 h; second, the main difference between formulation dissolution rates can be inputed to fat excipient content and in much lesser extent to carboxipolymethylene content; third, the theopylline release rate was unaffected by compression force.