3D printing has existed for over 40 years! Still, we continue to use traditional 3D printing for a variety of practical applications today. For instance, 3D printing is frequently used to create low-cost manufacturing prototypes and help students explore engineering principles in school. In fact, 3D printing is even used to create custom jewelry and artwork. But wait – there's more! The more modern field of "bioprinting" takes 3D printing to the next level.
Rather than using plastics or metal to create a print, bioprinting uses natural materials. In terms of practical applications, medical researchers hope that bioprinting will help produce living tissue and organs for transplants and help develop more accurate personalized treatments. However, bioprinting is not as straightforward as 3D printing. The cellular complexity in a living organism makes it difficult to use the same traditional printing methods. When using inorganic materials, such as plastics or metals, a 3D printer will print out the object one layer at a time. This method is not as effective with bioprinting, especially when creating larger, adult-sized tissues and organs. The biomaterials, sometimes called bioinks, that are used in bioprinting are soft, liquid substances that make them more susceptible to distortion. To combat this distortion, bioprinters have to use a special gel or scaffold to support the cells.
In 2015, researchers from Carnegie Mellon University did just that by proposing the FRESH (Freeform Reversible Embedding of Suspended Hydrogels) technique that relies on a support bath to hold the bioinks in place. This allows for the printing process to remain stable and prevent potential malformations. In 2019, less than two years ago, Carnegie Mellon researchers applied FRESH techniques to create the first, full-sized bioprinted model of a human heart. The researchers used collagen as a key bioink that would be able to construct replicas of the complex structures within the heart.
Some of these structures included pulsing ventricles and heart valves that opened and closed, just like a real heart. As outlined in FRESH methodology, the collagen was placed in a gelatin support bath to prevent it from collapsing during the printing procedure. The heart itself was created from alginate, a substance that originates from seaweed and selected for its similar properties of heart tissue. Later, researchers tested the bioprinted heart using sutures. The alginate was able to stretch and support the sutures appropriately, mimicking a real heart's behavior. Overall, the bioprinted heart was not fully functional—its cells were beating individually rather than collectively as a group. More importantly, the heart introduced major developments to practicing FRESH techniques and began the world another step closer to bioprinting functional organs.
While many improvements are necessary to launch an organ-producing enterprise, future successful bioprinting of organs will have significant implications in medicine. The hassle of organ donations and endless transplant waiting lists may no longer be needed! In case of natural disasters, a readily available bioprinter could quickly print any needed bodily structures and save lives without needing to transport patients. Bioprinting could be used for educational purposes for surgeons-to-be. The list goes on! We don't know what the future of bioprinting will look like, but one thing is for sure: bioprinting has the potential to transform medicine forever and save millions of lives.
Henderson, Emily. “3D Bioprinting Paves Way for Functional Adult-Sized Tissues and Organs.” Medical News, Medical News, 16 Feb. 2021, www.newsmedical.net/news/20210216/3D-bioprinting-paves-way-for-functional-adult-sized-tissuesand-organs.aspx.
Lynn, Bryan. “Scientists Create First Full-Size 3D Printed Human Heart Model.” VOA, VOA Learning English, 6 Dec. 2020, learningenglish.voanews.com/a/scientists-create-firstfull-size-3d-printed-human-heartmodel/5686230.html#:~:text=American%20researchers%20say%20they%20have,to%20 a%20real%20human%20heart.
Saplakoglu, Yasemin. “How Scientists 3D Printed a Tiny Heart from Human Cells.” LiveScience, LiveScience, 17 Apr. 2019, www.livescience.com/65257-3d-printed-heart-humantissue.html#:~:text=Scientists%203D%20printed%20a%20heart,a%20rabbit's%20using %20human%20tissue.&text=It%20has%20four%20chambers%2C%20blood,a%20heart %20using%20human%20tissue.
Vialva, Tia. “Carnegie Mellon Advances FRESH 3D Bioprinting to Rebuild the Heart.” 3D Printing Industry, 2 Aug. 2019, https://3dprintingindustry.com/news/carnegie-mellon-advancesfresh-3d-bioprinting-to-rebuild-the-heart-159473/.