By Matthew Munson, Virginia Tech
A few years ago, a carpenter named Richard van As suffered a terrible accident while working in his shop. He severed four fingers on his right hand with a saw, which all but condemned the carpenter’s livelihood when the doctors informed him that the fingers could not be reattached. However, van As proved himself to be a resilient and resourceful innovator once he realized the price of fitted prosthetics. Today, Richard van As is the co-founder of the company Robohand, which uses 3D printers to cheaply manufacture custom prosthetics that do not require a physician’s assistance to fit and assemble. All of the instructions for taking measurements and placing the order can be found online for free. Once the specifications are submitted, the prosthetic will arrive in the mail with instructions on how to attach the plastic limb at home. The 3D printed limbs are a fraction of the cost of a prosthetic ordered by a physician. For individuals with a low income or anyone without health insurance, Robohand has made a normal lifestyle possible.
3D printing and other forms of additive manufacturing have recently shifted the manufacturing industry’s focus to developing cheaper, faster methods of churning out products. The first 3D printer was constructed in the 1980s. It was able to extrude a liquid polymer in simple geometric shapes that hardened when exposed to UV radiation. Since then, the technology of 3D printing and digital computing has made leaps and bounds forward in its development. The modern 3D printer has a defined x-y-z axis within its machinery which allows a nozzle to move on its track and extrude the chosen building substance in layers. Most 3D printers extrude one of two types of plastic polymer. However, specialized filaments have been developed in the past few years, including polymers that are clear after cooling, conductive polymers for printing circuits, and biological polymers that have different properties depending on the print project. A 3D object can be constructed in a matter of minutes using a 3D printer, although larger objects require more time. The objects can have both solid and hollow portions. Projects can also have multiple parts that are assembled after printing. Most 3D printers are able to extrude the layers of molten plastic with millimeter precision.
3D printing will eventually make its way into the category of mainstream household electronics. Forgot to buy more hanging hooks and the laundry is almost done? Why not just print a few? Need a pencil cup or cell phone stand for your desk? How about an extra measuring cup for the kitchen? Several online file sharing sites already exist where 3D print users post files of the projects they’ve designed so far, allowing anyone else to download the design and either customize or print the object as well.
The technology of 3D printing has proven very useful to the life sciences and medical community. Affordable prosthetic limbs are just one example of how additive manufacturing is changing the scientific world. Scientists have managed to develop a slurry of buffer that allows cells to be loaded into a 3D printer and extruded in a similar fashion. The possibilities of a biological 3D printer are immense (one notable one being that the layers of tissue found in vivo in an organism can be replicated in a laboratory setting). Just like multicolored printer cartridges, several different cell types can be prepared and printed into layers that simulate a real biological structure. This structure could be an organ, which can be formed around a biological scaffold that slowly and harmlessly decays over time when transplanted into an organism. In the future, it is possible that new organs could be built in a matter of hours from the cells of the recipient. This would eliminate both rejection issues and the need for a live donor in the case of organ failure. Another use for 3D printing in the scientific community is creating artificial membranes and tissues that simulate real, in vivo conditions. These constructs could be used for a variety of different experiments, such as those pertaining to drug targeting and permeability. Artificial tissues made by 3D printers could also test the effects of environmental factors like physical forces and UV exposure on the cell types, helping scientists to draw conclusions about the same effects on the organism under study.
On a smaller scale, a chemist at the University of Illinois has designed a 3D printer capable of making several thousand different organic molecules from only a handful of starting compounds. The machine works systematically, adding the parts of a molecule one by one and washing away the byproducts in between each reaction. Pure organic molecules designed on a computer can be produced quickly and without the hassle of coming up with a series of reactions to arrive at the desired product. Unique natural compounds, such as the drugs found in plants in the remote portions of the Amazon rainforest, could be printed as if they were brochures.
To learn more about 3D printing and its applications to the biological community, I recommend reading the article “3D Bioprinting of Tissues and Organs,” published online by Nature magazine. It gives a comprehensive overview of what advancements have been made thus far in the use of 3D printing by the life sciences community. An article from Popular Mechanics about a 3D printer for organic molecules can be found here.