3-D Printer Targets Human Tissue Fabrication

A new use of additive manufacturing technology is a machine called a 3-D Bioplotter that can fabricate a wide range of biomaterials.

According to Dr. Vladimir Mironov, director of the Advanced Tissue Biofabrication Center at the Medical University of South Carolina, one of the long-term goals is to print human organs such as kidneys and livers.

The Bioplotter uses a nozzle to print materials within temperatures ranging from -50 to 150C. The materials include calcium phosphate ceramics, degradable polylactic/polyglycolic acid polymers, and hydrogels such as alginate, agarose, fibrin and collagen. 3-D printers, such as the 3-D Bioplotter, are currently used to manufacture biodegradable scaffolds used for custom bone implants. In the future, machines may apply advanced microfluidics to print human stem cells.

The nozzle is driven by numerical control code supplied from a contour file. After transferring 3-D CAD data to a PC provided with the Bioplotter, it is processed by a special software package.

"Tissue spheroids will be used as building blocks," Mironov said in a presentation at Rapid 2010, held in Anaheim, CA May 18-20. He describes tissue spheroids as living materials with certain measurable, evolving and potentially controllable composition, material and biological properties. When they are placed closely together, tissue spheroids undergo fusion. After a structure is printed it would then go into a bioreactor.

In his presentation Mironov described his efforts to engineer small segments of a branched vascular tree by using vascular tissue spheroids. Without vascular systems, the organ wouldn't survive more than five hours," he says.

That's where the 3-D bioprinters play a key role because of their ability to create complex internal designs in minute layers.

The economics for the technology are promising considering that annual dialysis costs $75,000 and many people wait several years before receiving a transplant.

The Bioplotter shown at Rapid 2010 is a fourth generation machine that costs 150,000 Euros ($188,000).

The 3D-Bioplotter, developed by a German company called envisonTEC, operates in sterile environments in a laminar flowbox, which is a requirement of biofabrication. The technology was invented at the Materials Research Center in Germany.