Microencapsulation is a technology that has shown significant promise in biotherapeutics, and other applications. It has been proven useful in the immobilization of drugs, live mammalian and bacterial cells and other cells, and other biopharmaceutics molecules, as it can provide material structuration, protection of the enclosed product, and controlled release of the encapsulated contents, all of which can ensure efficient and safe therapeutic effects. This paper is a comprehensive review of microencapsulation and its latest developments in the field. It provides a comprehensive overview of the technology and primary goals of microencapsulation and discusses various processes and techniques involved in microencapsulation including physical, chemical, physicochemical, and other methods involved. It also summarizes the state-of-the-art successes of microencapsulation, specifically with regard to the encapsulation of microorganisms, mammalian cells, drugs, and other biopharmaceutics in various diseases. The limitations and future directions of microencapsulation technologies are also discussed. 1. Introduction Microencapsulation has gained importance in the fields of cell and tissue engineering, as well as in the development of drug formulations and oral delivery systems. There are a number of already marketed microencapsulated products for the delivery of pharmaceutics . The term microencapsulation, in this work, encompasses the terms microcapsules, microparticles, microspheres, and microemulsions. Generally, the term microsphere is employed for a homogeneous structure made of one continuous phase, and the term microcapsule is used for a reservoir-like structure with a well-defined core and envelope/coat. There exist a variety of microcapsules which can differ in size, composition, and function. The characteristics of the microcapsules ultimately depend on the final goal of the encapsulated product, as they can be used to entrap all sorts of substances: solids, liquids, drugs, proteins, bacterial cells, stem cells, and so forth. With such a range of substances that can be entrapped, one can conclude that microcapsules can have an assortment of objectives and applications, whether for drug delivery, enzyme retrieval, artificial cell and artificial tissue delivery, and delivery of microorganisms. This paper provides an up-to-date review of microencapsulation and its latest developments. It provides a comprehensive overview of microencapsulation technology, the primary goals of microencapsulation, and the processes and techniques involved. This includes
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