A new model of resorbable device degradation and drug release: transient 1-dimension diffusional model.

In the framework of resorbable devices, an increased demand for a better reliability in drug delivery systems emerged, based on resorbable polymers degradation control. These points influenced researchers to replace the trial-and-error approaches with model-based ones. In this context, we developed a transient 1-dimension model for degradation and drug release of resorbable polymeric drug loaded systems. Such model is thought to be applied to design specific devices based on the expected degradation time and drug delivery rates. It is based on the detailed conservation equations taking into account main physical-chemical parameters involved in polymer degradation and in drug release, all independently estimated. The model leads to a system of partial differential equations solved numerically, which predictions were verified through both literature and our data. Data of different authors, various systems and directly generated data were matched by model predictions. Reliability of parameter estimation procedures was also confirmed by accelerated life tests.