Fibers in therapy and cosmetics

A method of preparing a device for the treatment and/or prophylaxis and/or diagnosis of diseases and/or cosmetic conditions which comprises utilizing a functional material selected from host materials, emissive materials (EM), hole injection materials (HIM), hole transport materials (HTM), hole blocking materials (HBM), electron injection materials (EIM), electron transport materials (ETM), electron blocking materials (EBM), exciton blocking materials (ExBM), and metal complexes, wherein the device comprises at least one organic light emitting woven fiber and the device is an implantable probe, nasogastric tube, chest drain or stent.