Polymeric and lipid-based systems for controlled drug release: an engineering point of view

Aim of this chapter is to review the most common techniques to produce and to characterize systems for controlled drug release, giving particular emphasis to the fundamentals of the production processes and to the possibility to describe mathematically the phenomena involved in drug release, that is, looking at the processes from an engineering point of view. The most commonly used materials are briefly reviewed, both the polymeric materials (preformed and ad-hoc synthetized, natural, and synthetic) as well as the lipid materials. Then, the drug delivery systems’ preparation processes are presented and discussed. Particular focus is given to the preparation of micro- and nanoparticles based on preformed polymers, and to preparation processes for liposomes. Advanced characterization techniques for novel and conventional drug delivery systems are then presented. Last but not least, the most modern modeling approaches to describe the drug release from these drug delivery systems are reported and compared.