Mathematical models in drug delivery: how modeling has shaped the way we design new drug delivery systems

In this review we present some of the seminal contributions that have established the mathematical foundations of controlled drug delivery and led to the modern models. Mathematical modeling is no longer just a dry exercise in generating more and more complex models or a parametric fitting process, but rather an advanced analysis that can lead to a priori examination of a release/delivery process or a series of design equations that help the practitioner achieve a better formulation.