Disruptive Technologies for International Development
Sunday, May 26, 2019
Rendering of a cartesian robot by Puneet Kishor, based on a modular, hackable biology lab automation system by Modular Science released under the CC0 Public Domain Dedication.
Introduction
3D printing, most typically, uses a process known as Fused Deposition Modeling (FDM), sometimes also known as Fused Filament Fabrication (FFF). FDM printers use a thermoplastic filament that is heated to its melting point and then extruded, layer by layer, to create a three dimensional object. The 3D object is designed in a CAD program such as OpenSCAD that can then export STL files that are read by a Slicer program. The Slicer literally slices the 3D model into layers and then prepares G-Code that can be read by a firmware. Other 3D printing techniques include Stereolithography (SLA), Direct Light Processing (DLP), Selective Laser Sintering (SLS), Material Jetting (MJ), Drop on Demand (DOD), Binder Jetting (BJ), and Powder Bed Fusion.
If the printhead (the extruder) in a 3D printer is replaced with a mechanism that pushes out a biological substrate, we get a 3D bioprinter that can be used to print human tissue and even entire organs.
Disruptive Power
The obvious disruptive potential of 3D printing is in rapid prototyping, obviating the need for a time-consuming design – produce – test – redesign – approve cycle while doing so with streamlined or almost negligible physical infrastructure. Sufficiently sophisticated and fast 3D printing technology can also disrupt traditional delivery systems whereby purchased objects don’t have to be shipped from point A to point B. Instead, the design can be sent online and printed at the destination. But the really powerful disruption lies in the area of human tissue printing, for example, using a 3D printer to print organs for transplanting in patients, or printing human skin tissue for burn victims. This can short-circuit long waits for human organs or make rehabilitation possible in remote areas with a scarcity of human tissue.
Potential for Development
From printing of replacement machine parts in manufacturing and agriculture to high-tech industrial manufacture to printing of prosthetics and human tissue for accident and burn victims, the application of 3D printing in developing countries is not unlike that in the more advanced economies. But, since it requires a lot less investment in infrastructure than traditional manufacturing, 3D printing does promise a bigger boost to emerging economies.
Caveats
The clear danger of 3D printing is in its use to print prohibited or restricted objects such as guns or other weapons. Use of 3D printing to create parts use in manufacture also opens up the potential for bad design and fabrication causing failure of the larger systems, something that doesn’t happen in the more traditional 2D printing. There have been reports of 3D printing of experimental body parts and implants especially from the biohacking movement. Such experimentation, while a hallmark of a vibrant and creative culture, can also be dangerous for the practitioners. As with everything, a viable solution going forward in this field is going involve a mix of regulation and education.
Resources
Bioengineers clear major hurdle on path to 3D printing replacement organs
Bioengineers have cleared a major hurdle on the path to 3D printing replacement organs and tissues with a new open-source technique for bioprinting tissues and templates with exquisitely entangled vascular networks similar to the body's natural passageways for blood, air, lymph and other vital fluids.
Mimicking the growth of human organs through 3D bio-printing
If you need a heart or liver or lung transplant, imagine if you could simply 3D-print the necessary new organ instead of having to wait for a donor. That may still be decades away, but Adam Feinberg – an Associate Professor at Carnegie Mellon – explains the steps his lab is taking to bring this vision from science fiction towards clinical reality.
3D printing is gaining ground in the medical field. The Victoria Hand Project (VHP) is using the technology to develop ground-breaking prosthetics for people in developing countries – improving their lives significantly. Recently, the project has been selected as one of the top ten finalists of the Google.org Impact Challenge in Canada, a competition created to find and fund the most innovative nonprofits. Here’s more about VHP's work, challenges, and the individuals benefitting from their efforts.
GE has just opened the first of what they expect to be many “Multi-Modal” facilities in Chakan, India that they believe will completely revolutionize how their products are manufactured. … It all started with a fuel nozzle, a component that is ubiquitous to any engine that runs on liquid fuels. The fuel nozzle is the engine part that sprays fuel into the engine, where it is burned and causes the entire device to run. Needless to say, a fuel nozzle needs to be durable, and the geometry of the nozzle itself needs to be exacting so the correct amount of fuel is released at the correct rate. And most importantly it needs to be able to really take a lot of heat, on average about 3000ºF worth of it. Because of its importance, and complexity, the fuel nozzle in a GE jet engine became the ideal component to be redesigned and manufactured using 3D printing technology. … The result is a single part that completely replicates all of the twists, turns and interior chambers that the old fuel nozzle needed to have fabricated using multiple parts that would need to be welded and assembled. Instead, the new fuel nozzle was manufactured using a direct metal laser melting 3D printing process that turns thin layers of metal powders into fully-solid metal parts. Not only is it a single part, but it is 25% lighter and a remarkable five times stronger than its traditionally manufactured predecessor. As part of GE’s next generation LEAP engine, the fuel nozzle ended up saving about $3 million per aircraft, per year for any airline flying a plane equipped with one.
The advent of 3D bioprinting offers new opportunities to create complex vascular structures within engineered tissues. However, the most suitable sacrificial material for producing branching vascular conduits within hydrogel-based constructs has not yet been resolved. Here, we assess two leading contenders, gelatin and Pluronic F-127, for a number of characteristics relevant to their use as sacrificial materials (printed filament diameter and its variability, toxicity, rheological properties, and compressive moduli). To aid in our assessment and help accelerate the adoption of 3D bioprinting by the biomedical field, we custom-built an inexpensive (< $3000 CAD) 3D bioprinter. This open-source 3D printer was designed to be fabricated in a modular manner with 3D printed/laser-cut components and off-the-shelf electronics to allow for easy assembly, iterative improvements, and customization by future adopters of the design. We found Pluronic F-127 to produce filaments with higher spatial resolution, greater uniformity, and greater elastic modulus than gelatin filaments, and with low toxicity despite being a surfactant, making it particularly suitable for engineering smaller vascular conduits. Notably, the addition of hyaluronan to gelatin increased its viscosity to achieve filament resolutions and print uniformity approaching that with Pluronic F-127. Gelatin-hyaluronan was also more resistant to plastic deformation than Pluronic F-127, and therefore may be advantageous in situations in which the sacrificial material provides structural support. We expect that this work to establish an economical 3D bioprinter and assess sacrificial materials will assist the ongoing development of vascularized tissues and will help accelerate the widespread adoption 3D bioprinting to create engineered tissues.
Israeli researchers have created what they say is the world's first 3D-printed heart, made using cells and biological material from a human patient. According to a paper published in the journal Advanced Science, the miniature organ includes blood vessels, in what the team from Tel Aviv University (TAU) are hailing as a significant step forward for the field of regenerative medicine. "This is the first time anyone anywhere has successfully engineered and printed an entire heart replete with cells, blood vessels, ventricles and chambers," Tal Dvir, lead author of the study from TAU, said in a statement.
The tissue engineering field has emerged as a solution to the shortages of organ and transplantation needs. As of present, there are approximately 121,142 people in the United States awaiting an organ transplant and only 30,975 transplants were performed in 2015. The amount of people on the transplant waiting list has grown rapidly since 1991 and has greatly outpaced the amount of transplants being performed. This has provided incentive for researchers to develop methods of creating artificial organs. The traditional approach to create functioning 3D tissue is to seed cells onto biopolymer scaffolds designed to direct cell proliferation and differentiation. However, there are many challenges such as limited biopolymer availability and difficult methods for seeding of various cell types. This approach has often failed to provide an efficient transportation system of growth media including oxygen, nutrients, growth factors, and water, all of which are required for the generation of thick, viable tissues or organs. Recent advances in the field have made these challenges possible by way of additive manufacturing, also known as three-dimensional bioprinting (3D bioprinting).
For the past decade, 3D printing (3DP) has become popular due to availability of low-cost 3D printers such as RepRap and Fab@Home; and better software, which offers a broad range of manufacturing platform that enables users to create customizable products. 3DP offers everybody with the power to convert a digital design into a three dimensional physical object. While the application of 3DP in developing countries is still at an early stage, the technology application promises vast solutions to existing problems. This paper presents a critical review of the current state of art of 3DP with a particular focus on developing countries. Moreover, it discusses the challenges, opportunities and future insights of 3DP in developing countries. This paper will serve as a basis for discussion and further research on this area.
