More than 120,000 people in the United States are currently awaiting organ donation and approximately 6500 people die each year while awaiting organ availability. Although one donor can save up to 8 lives through organ donation, that isn’t enough to meet the growing need for organs and tissue.

Fortunately, advancements in 3D printing are paving the way for the creation of replicas of transplantable organs using biological material. By modifying a consumer-level 3D printer that cost $1000, researchers at Carnegie Mellon University were able to take magnetic resonance images of coronary arteries and 3D images of embryonic hearts and bioprint them with remarkable resolution.

Normally, 3D printers use plastic or metal to create inorganic objects (such as prosthetics for amputees). The challenge with printing organic material is that its too soft and collapses under its own weight; it is like printing Jell-O. Ironically, the researchers applied the manner in which Jell-O molds can be used to suspend fruit as a solution to this problem. They were able to print biological material such as collagen or fibrin by suspending it in a supportive gel. After the bio-modeled object—an artery, for example—was created, the scientists warmed the gel to body temperature to melt it away, leaving the bioprinted structure intact.

The researchers named their 3D printing method FRESH (Freeform Reversible Embedding of Suspended Hydrogels). By hacking a 3D printer on the consumer market, the researchers were able to reduce the cost of bioprinting by thousands of dollars. Although the concept of printing organic material is not new, current techniques use machines that cost more than $100,000. 

The team’s method also has an edge over other technologies because of its unprecedented precision in producing complex biological structures. They have created a miniature human brain, a baby chicken heart, and an artery tree in detail using magnetic resonance imaging and microscopy images as models.

Their next undertaking is to inject heart cells into the bioprinted tissue to create a working, beating heart. The goal is to develop the technology to the point where patients can have access to 3D-printed replacement organs instead of waiting for a donor.

To speed up the advancement of this technology, the researchers plan to release their printer designs under an open-source license.

The technology for 3D printers began in 1983 when Charles Hull invented stereolithography, a type of printing that could output 3D objects using a laser that solidifies a polymer material. At first, the material wasn’t sturdy enough to create durable objects, but by the early 1990s blended plastics and powdered metals (nanocomposites) were introduced to 3D printers to produce strong, longer-lasting objects.

It wasn’t long before medical researchers began to think about applying the technology of 3D printers to the biological sciences. This became a reality in 1999 when scientists at the Wake Forest Institute for Regenerative Medicine used a 3D printer to create a synthetic frame of a human bladder. They then coated it with cells to grow working organs. In 2002, the first miniature functional kidney capable of filtering blood and producing urine was printed, and in 2010, Organovo—a bioprinting company—printed the first blood vessel.

Today, the technology is being used for the generation and transplantation of skin, bone, and heart tissue. 3D bioprinting is also employed for developing tissue models for research, drug discovery, and toxicology.

As for the future, fully functional bioprinted organ transplants represent an opportunity to eliminate the need for a donor waiting list. At this point, it’s just a matter of time.


  1. Andrews R. Researchers can now 3D print a human heart using biological material. IFL Science website. October 26, 2015. Accessed November 20, 2015.
  2. Facts and Myths. American Transplant Foundation website.  Accessed November 20, 2015.
  3. Harris W. How 3-D bioprinting works. How Stuff Works website. Accessed November 20, 2015.
  4. Morad R. Hearts and arteries could be 3D-printed cheaply. Discovery News website. October 26, 2015. Accessed November 20, 2015.
  5. Paone G. Scientists create 3D-printed heart and arteries. Regal Tribune website. October 16, 2015. Accessed November 20, 2015.