A mathematical model to simulate the drug release pattern from drug-eluting stents with biostable polymeric bulk and hydrophobic incorporated drug

DES, or drug-eluting stents, have the advantage of reducing restenosis rates relative to bare-metal stents. Modeling and simulation can be used to improve device performance. In this study, a general mathematical model for releasing a hydrophobic drug from a drug-eluting stent, DES, with a biostable coating is modeled. Most mathematical models allow the drug in the polymer to be released freely. This is suitable when the initial concentration of the drug in the polymer is less than the solubility, in which case the dissolution of the drug can be considered instantaneously. On the other hand, matrix devices can be loaded above solubility to provide zero-order release. to this end, we have equipped a model with a function that determines how the dissolution processes change with the dispersed phase discharge. The general model is analyzed with some limitations, and it is reduced to a new model that is consistent with previous studies. We examine the effects of initial drug loading and dissolution rate constant in numerically solving one of the new models, which is novel in DESs.