Manufacturing Human Organs

Forget toner cartridges; hydrogels and stereolithography are key in a new method to 3D-print complex tissues.

Zoom image: 3D printed liver on grid 3D printed liver on grid.

It looks like science fiction: A machine dips into a vat of translucent yellow goo and pulls out what becomes a life-sized hand.

But the seven-second video, which is sped up from 19 minutes, is real.

The hand, which would take six hours to create using conventional 3D-printing methods, demonstrates what engineers at the University at Buffalo say is progress toward 3D-printing human tissue and organs—biotechnology that could eventually save countless lives lost due to the shortage of donor organs.

From contact lenses to capillaries

“The technology we’ve developed is 10-50 times faster than the industry standard,” says Ruogang Zhao, the study’s co-lead author and an associate professor of biomedical engineering at UB. “And it works with large sample sizes that have been very difficult to achieve previously.”

The work, supported by the National Institutes of Health, centers on a 3D-printing method called stereolithography and jelly-like materials known as hydrogels, which are used to create, among other things, diapers, contact lenses and scaffolds in tissue engineering.

The latter application is particularly useful in 3D printing, and it’s something the research team spent a major part of its effort optimizing to achieve its incredibly fast and accurate 3D-printing technique.

“Our method allows for the rapid printing of centimeter-sized hydrogel models,” says Chi Zhou, associate professor of industrial and systems engineering and the study’s other co-lead author. “It significantly reduces part deformation and cellular injuries caused by the prolonged exposure to the environmental stresses you commonly see in conventional 3D-printing methods.”

Researchers say the method is particularly suitable for printing cells with embedded blood vessel networks, a nascent technology expected to be a central part of the production of 3D-printed human tissue and organs.