Effect of maize starch excipient properties on drug release rate

The aim of the work was to determine the influence of pregelatinized maize starch properties on the dissolution rate of caffeine. The intrinsic dissolution rate apparatus was used to investigate the process of drug dissolution. Dissolution profiles of caffeine mixed with 5 different maize starch samples, using caffeine : starch ratio (4:1), were measured. The dissolution profiles of all caffeine-starch mixtures are presented, as well as the results of the mathematical model, consisting of the equations for caffeine concentration change and for the starch layer change in time. The values of 3 parameters of the dissolution model were estimated using non-linear regression analysis. Caffeine effective diffusivity in swollen starch layer was found to be strongly related to the starch swelling capacity. (C) 2012 Published by Elsevier Ltd.