CFD approach for simulation of API release from solid dosage formulations

A comprehensive mathematical model has been developed to study release behaviour of Active Pharmaceutical Ingredients (API) from pharmaceutical solid dosage oral formulations. An analytical model was found in Dynochem resources and a numerical model was developed using COMSOL Multiphysics software using computational fluid dynamics based on finite element method in order to solve mass transfer equations. Only molecular diffusion was considered in the model to predict mass transfer of API molecules through the porous matrix. The model was developed in two steps; in the first step Dynochem was used to fit the data and find the unknown parameters. Then, COMSOL Multiphysics was used for prediction of API concentration over time. The experimental results were taken from the lab for release of Paracetamol from HPMC tablets, in order to validate the modelling process. The result of the study showed that both modelling methods are relatively good predictors of experimental values and that even models with limited complexity can serve this purpose well. The results can be used as predictive tools for designing novel drug controlled release systems.