Surgical transplantation procedures such as heart transplants can be very difficult to work with and this is the reason why patients have to join a long waitlist, along with other patients, in the hopes of getting a transplant. However, researchers from the Carnegie Mellon University want to improve the chances of getting a transplant early by developing a method for 3D bioprinting soft tissues.

Currently, the 3D printing technology uses materials like titanium and silicone to create flexible plastic models used only for surgical planning. Unfortunately, replicating soft tissues can be difficult until today. The research is led by associate professor Adam Feinberg and it aims to demonstrate a new method of creating synthetic hearts and arteries using natural materials like fibrin and collagen. With their years of extensive research, they were able to accomplish printing soft tissues using a consumer-level 3D printer.

The technique of creating soft tissues was called Freeform Reversible Embedding of Suspended Hydrogels (FRESH) which involves printing gel in gel. This allowed the researchers to position the soft materials precisely inside the gel so that they can create it layer by layer.

To create anatomically correct heart and artery tissues, researchers rely on MRI images of patients. The printer then uses a small syringe to inject the layers of the second gel inside the transparent support gel. The support gel serves as the scaffold of the soft tissues. The support gel then melts away when immersed in ambient-temperature water, thus, leaving behind the living cells intact. Now, the researchers need to perfect the next step which is to incorporate the printed tissues in vivo.