Tag Archives: MTU

Synthesizing nerve tissues with 3D printers and cellulose nanocrystals (CNC)

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There are lots of stories about bioprinting and tissue engineering here and I think it’s time (again) for one which one has some good, detailed descriptions and, bonus, it features cellulose nanocrystals (CNC) and graphene. From a May 13, 2015 news item on Azonano,

The printer looks like a toaster oven with the front and sides removed. Its metal frame is built up around a stainless steel circle lit by an ultraviolet light. Stainless steel hydraulics and thin black tubes line the back edge, which lead to an inner, topside box made of red plastic.

In front, the metal is etched with the red Bio Bot logo. All together, the gray metal frame is small enough to fit on top of an old-fashioned school desk, but nothing about this 3D printer is old school. In fact, the tissue-printing machine is more like a sci-fi future in the flesh—and it has very real medical applications.

Researchers at Michigan Technological University hope to use this newly acquired 3D bioprinter to make synthesized nerve tissue. The key is developing the right “bioink” or printable tissue. The nanotechnology-inspired material could help regenerate damaged nerves for patients with spinal cord injuries, says Tolou Shokuhfar, an assistant professor of mechanical engineering and biomedical engineering at Michigan Tech.

Shokuhfar directs the In-Situ Nanomedicine and Nanoelectronics Laboratory at Michigan Tech, and she is an adjunct assistant professor in the Bioengineering Department and the College of Dentistry at the University of Illinois at Chicago.

In the bioprinting research, Shokuhfar collaborates with Reza Shahbazian-Yassar, the Richard and Elizabeth Henes Associate Professor in the Department of Mechanical Engineering-Engineering Mechanics at Michigan Tech. Shahbazian-Yassar’s highly interdisciplinary background on cellulose nanocrystals as biomaterials, funded by the National Science Foundation’s (NSF) Biomaterials Program, helped inspire the lab’s new 3D printing research. “Cellulose nanocrystals with extremely good mechanical properties are highly desirable for bioprinting of scaffolds that can be used for live tissues,” says Shahbazian-Yassar. [emphases mine]

A May 11, 2015 Michigan Technological University (MTU) news release by Allison Mills, which originated the news item, explains the ‘why’ of the research,

“We wanted to target a big issue,” Shokuhfar says, explaining that nerve regeneration is a particularly difficult biomedical engineering conundrum. “We are born with all the nerve cells we’ll ever have, and damaged nerves don’t heal very well.”

Other facilities are trying to address this issue as well. Many feature large, room-sized machines that have built-in cell culture hoods, incubators and refrigeration. The precision of this equipment allows them to print full organs. But innovation is more nimble at smaller scales.

“We can pursue nerve regeneration research with a simpler printer set-up,” says Shayan Shafiee, a PhD student working with Shokuhfar. He gestures to the small gray box across the lab bench.

He opens the red box under the top side of the printer’s box. Inside the plastic casing, a large syringe holds a red jelly-like fluid. Shafiee replenishes the needle-tipped printer, pulls up his laptop and, with a hydraulic whoosh, he starts to print a tissue scaffold.

The news release expands on the theme,

At his lab bench in the nanotechnology lab at Michigan Tech, Shafiee holds up a petri dish. Inside is what looks like a red gummy candy, about the size of a half-dollar.

Here’s a video from MTU illustrating the printing process,

Back to the news release, which notes graphene could be instrumental in this research,

“This is based on fractal geometry,” Shafiee explains, pointing out the small crenulations and holes pockmarking the jelly. “These are similar to our vertebrae—the idea is to let a nerve pass through the holes.”

Making the tissue compatible with nerve cells begins long before the printer starts up. Shafiee says the first step is to synthesize a biocompatible polymer that is syrupy—but not too thick—that can be printed. That means Shafiee and Shokuhfar have to create their own materials to print with; there is no Amazon.com or even a specialty shop for bioprinting nerves.

Nerves don’t just need a biocompatible tissue to act as a carrier for the cells. Nerve function is all about electric pulses. This is where Shokuhfar’s nanotechnology research comes in: Last year, she was awarded a CAREER grant from NSF for her work using graphene in biomaterials research. [emphasis mine] “Graphene is a wonder material,” she says. “And it has very good electrical conductivity properties.”

The team is extending the application of this material for nerve cell printing. “Our work always comes back to the question, is it printable or not?” Shafiee says, adding that a successful material—a biocompatible, graphene-bound polymer—may just melt, mush or flat out fail under the pressure of printing. After all, imagine building up a substance more delicate than a soufflé using only the point of a needle. And in the nanotechnology world, a needlepoint is big, even clumsy.

Shafiee and Shokuhfar see these issues as mechanical obstacles that can be overcome.

“It’s like other 3D printers, you need a design to work from,” Shafiee says, adding that he will tweak and hone the methodology for printing nerve cells throughout his dissertation work. He is also hopeful that the material will have use beyond nerve regeneration.

This looks like a news release designed to publicize work funded at MTU by the US National Science Foundation (NSF) which is why there is no mention of published work.

One final comment regarding cellulose nanocrystals (CNC). They have also been called nanocrystalline cellulose (NCC), which you will still see but it seems CNC is emerging as the generic term. NCC has been trademarked by CelluForce, a Canadian company researching and producing CNC (or if you prefer, NCC) from forest products.

3D printing and the environment (a panel discussion at the Woodrow Wilson International Center for Scholars), and new developments with metal 3D printing

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I have combined two 3D printing items here. The first is an announcement from the Woodrow Wilson International Center for Scholars about an upcoming panel discussion (from the Nov. 25, 2013 announcement),

The Environmental Impacts of 3D Printing

3D printing allows for cheaper and quicker production of complex and novel items. The technology has been used by industry to build prototypes and specialized parts since the 1980s, but interest in desktop applications of the technology has increased in recent years as prices for the machines have dropped.

Proponents of the technology often cite the environmental benefits of 3D printing, though fundamental questions remain: What technologies are involved in 3D printing? How efficient are these technologies in the use of materials and energy? Does the design of printed objects reduce end-of-life options? Does more localized production reduce the carbon footprint? Will simplicity and ubiquity cause us to overprint things, just as we do with paper?

Robert Olson explored some of these questions in his article “3D Printing: A Boon or a Bane?” in the November/December 2013 issue of the Environmental Forum. The article discusses the enormous potential of 3D printing and examines the paucity of research on the environmental impacts of the technology.

Join us at the Wilson Center on Dec. 13 for an event looking at the growth of additive manufacturing and the potential environmental implications of the technology.

When: Dec. 13, 2013 from 9 a.m. – 11 a.m. EST

Who:

  • Robert Olson, Senior Fellow, Institute for Alternative Futures
  • David Rejeski, Director, Science and Technology Innovation Program, Wilson Center
  • John Pendergrass, Senior Attorney & Director of the State Center, Environmental Law Institute

There is more information on the Event page.

While this panel discussion is likely to be focused on polymer 3D printing, there are other developments in the 3D printing world as per a Nov. 26, 2013 Michigan Technological University (MTU) news release (also on EurekAlert, Dec. 2, 2013),

OK, so maybe you aren’t interested in making your own toys, cellphone cases, or glow-in-the-dark Christmas decorations. How about a brake drum?

Until now, 3D printing has been a polymer affair, with most people in the maker community using the machines to make all manner of plastic consumer goods, from tent stakes to chess sets. A new low-cost 3D printer developed by Michigan Technological University’s Joshua Pearce and his team could add hammers to that list. The detailed plans, software and firmware are all freely available and open-source, meaning anyone can use them to make their own metal 3D printer.

This open access technology is being made accessible to the maker community, preferably to the highly skilled and experienced members, (from the news release),

Pearce is the first to admit that his new printer is a work in progress. So far, the products he and his team have produced are no more intricate than a sprocket. But that’s because the technology is so raw. “Similar to the incredible churn in innovation witnessed with open-sourcing of the first RepRap plastic 3D printers, I anticipate rapid progress when the maker community gets their hands on it,” says Pearce, an associate professor of materials science and engineering/electrical and computer engineering. “Within a month, somebody will make one that’s better than ours, I guarantee it.”

Using under $1,500 worth of materials, including a small commercial MIG welder and an open-source microcontroller, Pearce’s team built a 3D metal printer than can lay down thin layers of steel to form complex geometric objects. Commercial metal printers are available, but they cost over half a million dollars.

His make-it-yourself metal printer is less expensive than off-the-shelf commercial plastic 3D printers and is affordable enough for home use, he said. However, because of safety concerns, Pearce suggests that for now it would be better off in the hands of a shop, garage or skilled DIYer, since it requires more safety gear and fire protection equipment than the typical plastic 3D printer.

While metal 3D printing opens new vistas, it also raises anew the specter of homemade firearms. Some people have already made guns with both commercial metal and plastic 3D printers, with mixed results. While Pearce admits to some sleepless nights as they developed the metal printer, he also believes that the good to come from all types of distributed manufacturing with 3D printing will far outweigh the dangers.

In previous work, his group has already shown that making products at home with a 3D printer is cheaper for the average American and that printing goods at home is greener than buying commercial goods.

In particular, expanded 3D printing would benefit people in the developing world, who have limited access to manufactured goods, and researchers, who can radically cut costs of scientific equipment to further their science, Pearce said. “Small and medium-sized enterprises would be able to build parts and equipment quickly and easily using downloadable, free and open-source designs, which could revolutionize the economy for the benefit of the many.”

“I really don’t know if we are mature enough to handle it,” he added cautiously, “but I think that with open-source approach, we are within reach of a Star Trek-like, post-scarcity society, in which ‘replicators’ can create a vast array of objects on demand, resulting in wealth for everyone at very little cost. Pretty soon, we’ll be able to make almost anything.”

There is a paper and here’s a citation,of sorts,

“A Low-Cost, Open-Source Metal 3-D Printer,” to be published Nov. 25 in IEEE Access (DOI: 10.1109/ACCESS.2013.2293018)

Unfortunately I’ve not been able to locate this paper on IEEE {Institute of Electrical and Electronics Engineers]  Access.