Alginate Functionalization for the Microencapsulation of Insulin Producing Cells

Alginate is one of the well-studied natural polysaccharides that is most commonly used for the encapsulation of biological objects. Alginate hydrogels exhibit good biocompatibility and are often used to create shells around pancreatic islets of Langerhans in order to produce stable transplants, making possible long-term normoglycemia, and to prevent fatal hypoglycemia in absolute insulin deficient diseases. However, there exists the problem of rejection and loss of an encapsulated transplant owing to immune response. One of the lines of research into reduction of rejection and increase in the compatibility and stability of an alginate shell is the chemical modification of alginate. At present, a large number of chemically functionalized alginates are available for different purposes. This makes it possible to gain insight into relationship between the character of modification and the properties of modified alginates. The review highlights techniques and features of the chemical modification of sodium alginate designed for the microencapsulation of insulin producing cells.