3D printing technique yields artificial blood vessels

Until now, scientists have been unable to supply artificial tissue with nutrients that have to arrive via capillary vessels – something that has been a major stumbling block in tissue engineering. The Fraunhofer team claims to have solved that problem by using 3D printing and a technique called multiphoton polymerisation. Brief but intensive laser impulses were used to impact the material used and stimulate the molecules in a very small focus point so that crosslinking of the molecules occured. According to the researchers, the material then became an elastic solid, due to the properties of the precursor molecules that had been adjusted by the chemists in the project team. In this way, highly precise, elastic structures could be built according to a three dimensional building plan. Project leader Dr Günter Tovar, of the Fraunhofer Institute for Interfacial Engineering and Biotechnology in Stuttgart, said: "The individual techniques are already functioning and they are presently working in the test phase; the prototype for the combined system is being built." Dr Tovar believes the technique could be used to build up completely artificial organs based on a circulation system with blood vessels created in this fashion to supply them with nutrients.