Statistical evaluation of influence of viscosity and content of polymer on dipyridamole release from floating matrix tablets: a technical note

The present investigation described the influence of viscosity and content of HPMC on dipyridamole release using 32 full factorial design. All formulations had desired floating lag time (<2 minutes) regardless of viscosity and content of polymeric matrices. Results of multiple regression analysis indicate that both factors significantly affect the diffusion exponent (n), release rate constant (k), and percentage drug release at 1 hour, 4 hours, 6 hours, and 12 hour, (P<.05). Mechanism of drug release was found to be anomalous type to case-II transport depending upon the viscosity and content of polymer. It was found that content of HPMC had a dominant role in the initial phase of drug release, while in the later phase viscosity of HPMC Predominated