Science and Practice of Microencapsulation Technology

This chapter provides an overview of microencapsulation systems for drug delivery. Although microencapsulation technology has applications in many industries, its development has accelerated in the pharmaceutical industry. This chapter covers recent developments and trends in formulation and manufacture of microencapsulation for pharmaceutical applications. This complements existing literature pertaining to emulsification procedures and expands on a number of technologies available for the encapsulation of core materials. The properties of microcapsules are dependent on the physico-chemical properties of both core and shell materials. The key criteria in selecting an appropriate approach are highlighted under three broad categories. The most common microencapsulation methods are based on emulsification procedures that involve emulsifying polymer droplets and drug that subsequently result in solidification to form microspheres when the solvent carrier is extracted from the polymer phase. Finally a case study in which a water-soluble drug, captopril, is encapsulated is discussed with regard to formulation, manufacturing and characterization of the drug-loaded microcapsules.