The critical shortage of organ donors in our healthcare system is the reason I’m registered to be an organ donor and motivates my research to develop suitable replacement technologies in the field of regenerative medicine. Video below! It was an honor and privilege to take part in TEDxYouth@SanDiego, which brought 400 San Diego high school students together to interact and think deeply about the future. It was incredible to speak with so many students who are truly the Architects of the Future.

From TEDxYouth@SanDiego:

Using simple yet illustrative analogies to help non-scientists understand his scientific discovery process, Biomedical Researcher Jordan Miller explains to his young audience how he developed vascular structures through 3-D printing. This exciting research is an important complement to advances medical researchers have made in 3-D printing bioidentical human tissue and organs in the lab. it’s a remarkable prospect for the future of organ transplantation.

Deriving inspiration from a cross section of bread and the sugar structure arcing over his dessert, Dr. Miller describes how he combined his background in regenerative medicine, a passion for the maker movement and reliance on worldwide open sourcing to develop viable 3-D printed vascular systems that he demonstrates actually transporting blood.

Jordan Miller, Ph.D. is a post-doctoral researcher in the Tissue Microfabrication Laboratory at the University of Pennsylvania. Involved with the 3-D maker community since its infancy, Jordan uses a 3-D printer in his work in biomedical research and regenerative medicine and credits open-source collaboration and the maker movement as important contributors to the success of his research.

Here are the videos from Open Hardware Summit 2012, it was a great meeting again this year.

And here’s my talk about using RepRap 3D Printing for basic research in Regenerative Medicine. Thanks again to the awesome members of Hive76, especially Chris Thompson and Rob Vlacich.

One of our core members, Jordan Miller, has just published a scientific paper using RepRap 3D printing technology to engineer living tissues for regenerative medicine. I’ll give you a rundown of the science and a step-by-step guide of how Jordan got to this great spot in his career. Jordan is quick to point out that this is work that would not have been possible 5 years ago, or without the help of RepRap, Hive76, and this wonderful city of Philadelphia.

There are other labs around the world that are attempting what Jordan and the rest of the team at UPenn and MIT have been working towards. The end goal of regenerative medicine research is engineered tissues and replacement organs for treatment of human disease. As Science news says,

Imagine a world where if your heart or kidneys failed, you wouldn’t have to endure an agonizing, possibly futile wait for a donor whose organ your body might reject. Instead, a doctor would simply take cells from your own body and use them to “grow” you a new organ.

Other lines of research are attempting to 3D print directly with living cells and gel. These so-called “bioprinting” approaches involve loading cells and gel in syringes to be used as feedstock to create a structure from scratch. The problem is that healthy liver cells, for example, usually die of starvation (lack of nutrients) and suffocation (lack of oxygen) while enduring the slow 3D printing process.

Jordan’s 3D printed vasculature approach was inspired by whole organ vascular casts like this one.

Enter Jordan and his innovation: since vasculature provides the lifeblood to resident cells, why not focus on the vasculature first?

Jordan and the rest of the research team at UPenn and MIT have developed a new way to create vasculature for living tissues. This 4 step process involves: 1) 3D printing a network of sugar filaments, 2) surrounding it with living cells in a gel, 3) dissolving away the sugar to leave behind a vascular network for 4) the delivery of nutrients and oxygen. He accomplished this with a custom built 3D printer, extruder and control software.

Here’s a step-by-step of Jordan’s many year process:

1. Get a crazy idea to link sugar and vasculature when comparing the interior of a 3D print to a capillary network.
2. Get a PhD in bioengineering
3. Move to Philadelphia
4. Join a hackerspace
5. Get introduced to 3D printing, MakerBot and RepRap
6. Assemble your first MakerBot
7. Invent a heated build platform to dry your sugar while printing.
8. Add a heater to the Frostruder so you can print molten sugar.
9. Assemble a customized RepRap Mendel that fits your new extruder.
10. Get help from your hackerspace to properly control your pneumatic extrusion.
11. Work for months perfecting recipes and methods for printing vasculature.
12. Write it all up in a research paper and submit!

You can read the Penn press release about this awesome science, an overview from Science News, or the full paper. A more detailed post about the hardware used in this project will follow and soon you’ll be able to make your own sugar extruder. (It prints chocolate too!)

Microbial "paper" formed by peeling a layer from a kombucha "pellicle" (a.k.a. SCOBY)

Microbial cellulose is unlike any material I have ever handled, and it has some remarkable properties.  It is almost pure cellulose — no lignin, no hemi-cellulose etc., so, unlike plant-derived cellulose, you can grow it and use it in its raw form with no chemical processing.  The cellulose molecules are unusually long in comparison to plant-derived cellulose, and the fibrils that the Aceteobacter Xylinum bacteria produce are arranged as stacks of microporous, web-like membranes.  As a result, the material has a surprising strength to weight ratio and endures repeated folding without apparent weakening.  It feels like parchment, but it is extremely hydrophylic and can hold 100x its dry weight in water.  The fact that it is a naturally occurring  hydrogel makes it a great raw material for aerogels and the like, and the fact that it is organized as layers of microporous membranes makes it a good candidate for various kinds of semi-permeable barriers.

To me, it seems like the ultimate green material — no fertilizers, no machinery, little or no post-processing, strong, biodegradable and just generally useful for all sorts of interesting of applications.  Plus, it can be made from waste sugar and can ultimately be recycled by inclusion in paper, or by breaking the cellulose down into sugar and making new cellulose.  What’s not to love?

Cellulose culture using iced tea mix, yeast and water

Anyone can make this stuff.  All you need is a kombucha “mother”, some yeast, some sugary medium and a container in which to grow the stuff.  Here’s a picture of a five gallon bucket that I filled with instant iced tea mix, a packet of yeast and five gallons of water.  I tossed in some fragments from a kombucha mother, poured the  whole shootin’-kaboodle into a shallow tray and within a week, I had a  four square foot mat of cellulose that looked like this:

Microbial cellulose raised in culture of instant iced tea mix

A cellulose culture grown in sugar water and vinegar

Of, course, the iced tea mix was a mistake — the artificial color made the resulting cellulose incredibly gross looking.  It literally looked like someone had vomited their guts up, with the cellulose gel mat playing the role of “giant expelled stomach”.

As a parallel experiment, I raised some cellulose in a culture of sugar water, vinegar and yeast.  This made almost pure white cellulose that cleaned up nicely.  The yield of this “vinegar and sugar” batch seemed slightly lower than the “instant iced tea” batch, but the improved aesthetics may be worth the reduced yield.

I am planning to use the material in a number of ways — I converted the iced tea cellulose into shredded cellulose gel and then dried it in methanol, with the intent of using the fibers to make strong, biodegradable composites.  I also intend to use the sheets for composites and I plan to make some thick structures in order to see if I can convert them to cellulose aerogel.

Sheet of sugar-water & vinegar raised cellulose after quick rinse