ABSTRACT
This chapter provides a theoretical basis for the use of size reduction techniques to solve the formulator's challenge with poorly water-soluble Drug Substance (API). It describes various methodologies available for size reduction, and outlines capabilities and limitations of each. The chapter presents some example for where size reduction techniques to nanoparticle sizes have been successfully applied to poorly water-soluble APIs. These examples will include drugs intended for oral and parenteral administration. Microfluidization is a process involving a high-pressure fluids processor that delivers unique product capabilities, including particle size reduction to nanosized particles for dispersions, emulsions, and liposomes. Particle size reduction involves input of energy that gets disseminated during micronization process, along with formation of smaller particles having new surfaces. Poorly water-soluble crystalline APIs are becoming increasingly good candidates for the micronization process in the preparation of biocompatible and pharmaceutically acceptable nanoparticulate formulations. The chapter discusses diffusion-controlled crystal growth theory and adsorption-layer theory.
