Encapsulating the Cells

The biomaterial used for encapsulating the IOL is a type of hydrogel – alginate, made of seaweed polysaccharides. It is an aqueous polymer transformed to a biocompatible hydrogel following crosslinking with a divalent cation. Alginate creates only a minimal foreign-body response at implantation sites and, as such, is widely used as a scaffold for encapsulation many cell types. In parallel, we’re testing more advanced, synthetic hydrogels, for the same mission.


The macrocapsule uses alginate as a scaffold for cells to function. Two types of alginate are used in the manufacturing of the device: HG (high guluronic acid) is used for islet immobilization and HM (high mannuronic acid) impregnated in a Teflon membrane is used to protect from the immune system. Alginate is a biocompatible polymer which creates a minimal foreign-body response. As such, it is widely used as a scaffold for encapsulation of islets and cells.