samples read in a Labsystems Multiskan plus colorimetric plate reader at 450 nm (MTX Labsystems, Vienna, VA). Nickel mesh support Micro-PEF nickel mesh with a 19 mm aperture (Tecan, Weymouth, UK) was used as a supportive mesh for the electrospun membrane. Micro-photoelectroforming is a process whereby metal is electrodeposited within a photolithographically defined resist mould. It is a very precise process whereby micro- parts can be manufactured with sub-micron accuracy. This process allows extremely thin meshes to be made. Cells were cultured directly onto this mesh, then stained using antibodies (as previously described) to demonstrate this material was not toxic to cells and that the cells would grow on this material. To produce the complete composite bioartificial membrane, we developed the novel strategy of electrospinning collagen nanofibres directly onto the micro-PEF nickel mesh by using it to replace the aluminium foil in the above process. 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