| Abstract: | Research on novel implantable rubbery polyisobutylene‐based biomaterials carried out at the University of Akron during the past ～15 years is outlined. Specific attention is paid to recent investigations focusing on the synthesis of semipermeable amphiphilic networks designed to be used as immunoisolatory membranes. The membranes envelop insulin‐producing living pig beta cells. They are biocompatible to the host (human) and the guest (beta cells) and remain permeable for many months in vivo. They are rubbery slippery, robust, sterilizable, optically transparent, with controlled pore dimensions that allow the in‐diffusion of glucose and nutrients, out‐diffusion of insulin and wastes, but they do not allow the entry of immunoproteins (IgG). The pores remain permeable for many months in vivo. The membranes are made by copolymerizig/crosslinking hydrophilic (meth)acrylates with methacrylate‐telechelic polyisobutylenes. Controlling the molecular weights of the constituent segments controls the pore sizes of the membranes. Immunoisolated pig beta cells enveloped in our membranes and implanted subcutaneously in a rat have corrected severe hyperglycemia. |
