▎ 摘　　要

NOVELTY - The enclosure has a compartment and a wall separating the compartment from an environment external to the compartment, where the wall comprises a perforated graphene-based material layer and a substrate layer that is affixed directly or indirectly to the perforated graphene-based material layer, and the enclosure is not cytotoxic when the enclosure is implanted into a subject. The substrate layer comprises a fibrous layer comprising a set of polymer filaments. The compartment is in fluid communication with the external environment. USE - Enclosure for substance i.e. pharmaceutical, in an environment i.e. biological environment (all claimed), in contact with biological tissue for treating diabetes. ADVANTAGE - The enclosure excludes immune cells and immune complexes from entering the enclosure from the environment external to the enclosure. The enclosure beneficially promotes cell or tissue viability or growth, reduces or prevents infection, improves vascularization to or near the enclosure, improves biocompatibility, reduces biofouling, and/or reduces risk of adverse reactions. DETAILED DESCRIPTION - The substrate layer comprises additive selected from group consisting of pharmaceuticals, cells, growth factors, clotting factors, blood thinners, immunosuppressants, antimicrobial agents, hormones, antibodies, antigens or an antibody-binding fragment, minerals, and nutrients. INDEPENDENT CLAIMS are also included for the following: (1) a method for releasing a substance (2) a method for preparing an enclosure (3) a method for improving biocompatibility of an enclosure (4) a method for reducing cytotoxicity of a device (5) a coated therapeutic device. DESCRIPTION OF DRAWING(S) - The drawing shows a schematic block diagram of an enclosure a using graphene in an immunoisolation process.