Studies to predict the effect of pregelatinization on excipient property of maize and potato starch blends.

This study focuses on the effect of co-processing on physicochemical and drug release properties of starch mixtures. Different mixtures of native maize and potato starch were pregelatinized for different time intervals. The pregelatinized starch mixture was observed to have higher amylose content than that of native starches. The flow properties of starch mixtures were found to improve after pregelatinization. FTIR and XRD showed changes in structure and crystallinity of native starch due to pregelatinization. The FESEM images showed complete disruption of granular structure of native starch. Native starch was found to be more viscous than pregelatinized starch and all starch samples exhibited Non-Newtonian shear thinning behaviour. The tablets prepared from native starch showed rapid release of drug compared to the modified starches, and increase in the amount of potato starch resulted in sustained drug release. This indicates the utility of pregelatinized starch mixtures with high proportion of potato starch in sustained drug delivery systems.