Blood vessels straight from your 3D printer
16 September 2011
Fraunhofer researchersare applying new techniques and materials to come up with artificial blood vessels in their BioRap project that will be able to supply artificial tissue and possibly even complex organs in future. Scientists at Fraunhofer are working on a technology to generate tiny biomaterial structures by combining two different techniques: 3D printing technology already established as a rapid prototyping technique, and a polymer science development called multiphoton polymerization.

A 3D inkjet printer can generate 3-dimensional solids from a wide variety of materials very quickly. It applies the material in layers of defined shape and these layers are chemically bonded by UV radiation. This already creates microstructures, but 3D printing technology is still too imprecise for the fine structures of capillary vessels, which was why the researchers combined the technology with two-photon polymerization.
Brief but intensive laser impulses impact the material and stimulate the molecules in a very small focus point so that crosslinking of the molecules occurs. The material becomes an elastic solid, due to the properties of the precursor molecules that have been adjusted by the chemists in the project team. In this way highly precise, elastic structures are built according to a 3-dimensional building plan.
As the 'printed' blood vessels have to be flexible and elastic and interact with the natural tissue, they are 'biofunctionalised' so that living body cells can dock onto them. The researchers integrated modified biomolecules – such as heparin and anchor peptides – into the interior walls of the vessels and developed inks made of hybrid materials that contain a mixture of synthetic polymers and biomolecules. The artificial vessel can only work in the same fashion as its natural model if an entire layer of living cells can be established in this way.
Fraunhofer says that it is establishing a basis for applying rapid prototyping to elastic and organic biomaterials. The vascular systems illustrate what opportunities this technology has to offer, including the future building of completely artificial organs based on a circulation system with blood vessels created in this fashion to supply them with nutrients.
These findings will be shown at the Biotechnica Fair, Hannover, Germany October 11-13 2011.
Contact Details and Archive...