ABSTRACT
The microencapsulation technique which lately has become increasingly popular, ensures the inclusion of liquids, gases or fine solid particles with natural or synthetic polymers. Encapsulation offers many benefits from separation of components to avoid possible incompatibilities, extending the validity of components up to protection of different compounds from harmful action of various physico-chemical agents. Today, biodegradable microspheres became a great success that contributed to outline the concept of “drug delivery.” In addition, researchers have turned their attention to “cell encapsulation” to improve cell survival using biomaterials with remarkable flexibility, biodegradation and biocompatibility. The application of encapsulated cells is quite extensive, due to the increased viability, from human erythrocytes or pancreatic islets of Langerhans cells until hepatocytes. All these aspects are taken into account in this study together with the description of the most popular methods for preparing micro-particles, their release mechanism, the advantages of their use and various applications.