A membrane for implantation in soft tissue comprising a first domain that
supports tissue ingrowth, disrupts contractile forces typically found in
a foreign body response, encourages vascularity, and interferes with
barrier cell layer formation, and a second domain that is resistant to
cellular attachment, is impermeable to cells and cell processes, and
allows the passage of analytes. The membrane allows for long-term analyte
transport in vivo and is suitable for use as a biointerface for
implantable analyte sensors, cell transplantation devices, drug delivery
devices, and/or electrical signal delivering or measuring devices. The
membrane architecture, including cavity size, depth, and
interconnectivity, provide long-term robust functionality of the membrane
in vivo.