A significant part of tissue engineering is concerned with biomaterials fabrication and biomedical device development. Our group has experience with thermoplastic extrusion, centrifugal molding, and a variety of phase inversion techniques for fabricating hollow fiber membranes and open-celled porous foams.  A siginificant part of our research in this regard is directed toward the development of cell encapsulation technology.  In this approach, living cells are surrounded by a semipermeable membrane that physically isolates grafted cells from direct interaction with cells and tissues of the host.  The encapsulated cell compartment is coupled to the extracellular environment at the site of implantation by two-way diffusion of small molecules through the pores of the encapsulating membrane. We have developed a series of cell delivery catheters that allows one to deliver a variety of cells and cellular products that may be difficult to deliver using conventional pharmaceutical technology.  A cell containing catheter is shown in the bottom middle panel of the figure at right.