 So I'd like to talk to you a little bit about Rachel. Rachel's a PhD candidate in the Medicaid medics. I'll try this one more time, hang on. Mediated Matter Group at the MIT ME Lab. She hunts for ways to augment existing synthetic materials and devices with biological or living functions. Rachel holds a BS in biomedical engineering from the Wahuas UVA and has colorful paths starting up high accessibility diagnostic tools and running medical hackathons to encourage creative designs for hospital needs. So without further ado, Rachel, thank you. Great. Hi, guys. I'm just going to over. No, just to get the fun animation. Hi, guys. I'm Rachel. I am very excited to be here. This is my first deaf con. So I thank the biohacking village for adopting me and showing me this crazy world, having a lot of fun. So today, I want to take you on a little journey and share my world, which is full of what I call biohybrids and hybrid living materials. And you ask, what is this? It's kind of this unholy mashup where we hack the interface between living organisms and material processes so we can get the best of both worlds in one material that has kind of new functionalities. And because it is, so I'll start with a little history of the field, and then I'll go on and tell you a little bit about the things that I work on because it is 5.30 on a Saturday at deaf con. I thought I'd quiz you guys first and ask, what are we looking at? Does anybody know? Yes. It's the right audience. Yeah, so yeah, this is. I love Stanley Kubrick's kind of fictional imagined image of what it looked like at the dawn of humanity and some apis sitting here in a pile of bones. And I guess he's been here for a while in this desolate desert and suddenly picks it up, hits it on something, and is like, wait, this isn't just a bone. This is a tool. And then the rest is history. We make spaceships and get uploaded in outer space. So that is sci-fi, but lo and behold, the past million, four million years of history has had a lot of these really great realizations with materials. We've kind of found these raw materials, discovered them, and slowly figured out ways to manipulate them so that they have some higher function, some way to make it into an enabling technology. So bronze age, iron age, discovery of plastics and glass. Now we have silicon chips the size of our thumbnails that have incredible computing ability. And we can make skyscrapers. I'm adding one more just for DEF CON, which is virtual material just because our world is increasingly virtual or at least the relevant things in it. And I have this love-hate relationship with that because we too leverage a lot of tools that have been made for virtual environments to make our own biohybrids. But I also think we're not done yet in the physical world of materials. I'm really confident that we still have a lot of materials to find in which they have embedded, I guess, intelligence or ability to create intelligence from them. And we have to keep exploring that. So with that, I kind of pose the rhetorical question, what is the next great physical material revolution? And I'm biased. So the answer is, what if you were to consider a living cell to be a material component? What I love about living cells is that they're kind of fully loaded. They're this compact module that already has the hardware to be motile, has the ability to grow and replicate. This membrane that encases the whole thing is absolutely covered in sensors that will pick up on different things in the material environment and the chemical environment. And it kind of also encodes like a passcode in order to get in. On the inside, you have a bioreactor. It's something that can make many chemicals and proteins that are useful in interacting with things. Is this hackable? Of course. A lot of people know about the progress in synthetic biology to hack DNA. But what I love about biology is it's kind of hierarchical in structure and organization. So there's actually places to hack on every kind of level or scale of 10. You've got the chemicals, the DNA and RNA, and you've got proteins. And every place there's some kind of nuance that you can put your own functionalities in. So this sounds great. What are the drawbacks? The main thing keeping us from doing this, I guess, besides the obvious thing is that you have to keep these things alive, is that you want to be able to engineer this material in a controlled fashion. You need some standardization and repeatability so that whatever your input is, you get the expected outcome each time or output. Luckily, a lot of people have been thinking about this. In no specific order, I would list field of synthetic biology to make recombinant genes. Regenerative medicine that has physically put cells into 3D printers and started to try to print with them and organize them in 3D space. One word that I love that is very new is called synthetic morphology. This looks a lot like embryonic growth, but it's a way that we've tried to use our logic-gate-based recombinant genes to make patterns. And this is something that Alan Turing thought about from the very beginning of making computers. He had reaction diffusion, but if you can start to make emergent patterns, you can do so many things in physical space. So this is all great, and it's leading up to biohybrid materials, which I think of as the synthetic constructs of tissue engineering in these other fields mashed up because we're no longer trying to copy or replicate an organ in your own body, we're trying to make something completely new with the materials that we have. So enough hand-waving, let me just give you some real-life examples that already exist today. One of my favorite is BioBots, and these are, or at least this one, for example, has used rat heart cells in the actuation that they have laminated onto an elastic kind of shape, and it swims around like a jellyfish. It is stimulated by light, so depending on the color of light, you can actually steer the direction at it, it swims. And these things can be made at a scale small enough that they can swim through your bloodstream, which is awesome, but still, we're not there yet. Another cool one is this myothelium tower. This was built right outside MoMA in New York, and it is made of the, I guess, the body of the mushroom. And if the mushroom is kept alive, this has the ability to kind of grow back if you were to punch your hand through it or have other functions that continue to augment the structure as it remains outside. Another great one is biohybrid thread. This is where you embed bacteria into the core of a thread that is able to be woven or knit in a normal process. And people have been starting to use this in remediation processes to kind of sequester metals and things because the bacteria is actually protected by that thread as well as giving it kind of a material structure. And the last one is a living photograph. As you can see, we can turn a petri dish into kind of a light sensitive film. And beyond that, you can actually do things like edge detection and other computation on that picture, which is cool because we thought, you know, humans can do that, computer vision can do that, why not bacteria? So I hope I convinced you all to switch over to this field, because it's great. And now I'll tell you a little bit about what I've been working on. I'm part of the Mediated Matter Group, just to give that a quick introduction. It's a pretty kooky place. We are in fact not all biologists. Maybe only 12% or a group that's made up of computational designers, material scientists, and product designers, a whole lot of everything. Our fearless leader, Nuri Oxman, is actually a computational architect. She's an architect, but we often use computers to relate the natural world and things in between. So we work with glass, plastics, waxes, silkworms, bees, bacteria, and a lot of computational algorithms for growth. Okay, so second quiz of the day, what is this? Yeah, this is a hard one. Actually, close. So this is an object that has been produced on a 3D printer. It's a very special 3D printer. It's multi-material, which is how you're seeing all these materials jam-packed into this unified shape. And also, it's an inkjet printer. So it works a lot like any office inkjet printer. It just kind of builds on the last layer of material. Here's another view of it. It also happens to be a mask, which is why you're close with skull. And moreover, it was part of a series of masks called Vespers. So here you see kind of the artistic streak that sometimes motivates or starts some of the work we do. Vespers was a mission to take an object that has long since been outdated or not used, a death mask, and try to recreate it for the current era. Beyond that, there were kind of three evolutions of the mask in which we were given the hacker challenge that the mask must become alive or reborn as this death mask may be. So it's a very broad place to start, but there is a lot of technical work underlying this theme. So here we are. It actually took our team about three areas of hack to try and figure out how to do this. We had hacks and software in the physical printer and of course the cell. And I'm going to talk a little about each of these. So you're looking at another crazy thing. This looks like an MRI scan, but is in fact the file that we send to the 3D printer. I'll play that again. And what's happening here in the software is that our engineers decided we wanna be able to address every single point in 3D space and have the ability to assign a different material to each voxel, which is a 3D pixel. And to do that, we had to write a little of our own custom software. What it does is it actually, a lot of printers up until the last decade describe objects by outlining a certain space and using little polygons or triangles to design that 3D object and it's called a mesh. And then you kind of have a paint fill option to fill in each of those with a different material and that's the resolution you get. But if you instead can take every slice, every time the printer prints another layer on and make a file where you have a little binary control to say honor off for a certain material in a certain place, then what you can do is have this very fine grain control of a material distribution throughout your object. And I usually let the computational designers explain this part in much more length, but this is still not alive, but what we're getting is this beautiful material gradient and with material gradients, we're getting one step closer to what you see in nature. And you see this, this is actually an internal patterns as opposed to just external geometries. So that was one last thing. That was our custom software. The other great thing you'll need to do this is the little USB dongle that lets you kind of interface with the service operations side of the printer so you can use your software instead of theirs. So don't tell our printer company that. The next hack was the physical printer. And this is the peanut butter that fuses together our hardware with our living cell because what you need to do here is find a way that the materials you distribute are going to have some relevance or some way to communicate to your cells. And we started playing with one main thing. It was the fact that there was this one material we're looking at that had a lot of water-based properties and cells love water. It's kind of like the first place that you start saying like, okay, there's something here. And the material is actually traditionally the support material, the sacrificial material that leaves once the object is made. But using our software, which lets us control every point in space and make material gradients, we're actually able to find this happy medium where it's a mix of the hard material and this swellable soft material that's like a hydrogel where it actually stays within the 3D print and is structural. And the second thing we did was add aqueous chemicals to this that work as chemical signals. These are the things that the bacteria respond to and turn certain genes on and off. And that was the very glorious process of just kind of cutting into printer cartridges with a razor blade, switching out the materials, adding the chemicals we want, and then switching the RFID tags on top. So there's a lot of monkey business going on here, but yeah, as long as they keep it that simple, we can peel off an RFID tag. And last but not least, my favorite is the programmable cells that we use. We work with an E. coli, which is a very common kind of model organism for synthetic biology because it's so easy to iterate on. And this particular strain has a gate that looks for a certain chemical, and when it finds it, it makes a blue pigment. This is actually the plasmid for that. And yes, we use color creation as a great indicator for if our gene is on and off. Last but not least, we kind of extrapolated on the typical blue and white screen that we use for this bacteria to say we can actually do the entire color spectrum. And this was kind of like a one-up to the printer because the printer thought they could make an entire color spectrum. We said we can do the same thing with bacteria. So that in all was the many hacks that were involved in this process. And I wanted to show you what it creates in the end. This is a 3D mask that we've printed on our augmented printer. It started off as completely colorless. And we then put it through a process where we put a very thin coating of E. coli across the entire mask. We used hydrogel to adhere it on and put it in an incubator. And over the course of 48 hours, we start to see color development. And what's beautiful about this process is that each cell, each bacteria that is on the surface is like a little kind of display pixel. But it also has its own distributed rule set to know if it should be producing color or not. So these were the living, the rebirth of the death masks. So the next great thing that happens when you connect your virtual world with your physical world and your biological world is that you have some ability of control from the accuracy of the printer, but you also have a computer design environment. And we have a lot of simulations and materials now that let you understand forces and loads. And it's no different to get one that can help you predict both the diffusion of the chemicals and the response of the bacteria. And what this gives you is an in for not just kind of crazy biologists and tissue engineers to try and make things with biology, but anyone that has kind of an ability to use a CAD platform to design what they want, print it out and get what they expected. And this is what we love about making this entire platform from software to sell. So we did a lot of tests with that, a lot of fun tests. And you can see we actually started to use some of the other materials within the printer's design repertoire, including partially flexible materials and some different modes of expression. And while deaf masks are fun and all, a lot of you will be like, what can you actually make with this? And one of our examples, something that I love since I came from a hospital background, is the fact that you can use things that are, find areas that are already in much need of things like 3D printers. Like this example is a back brace for people who suffer scoliosis. In that case, a custom 3D printed brace is relevant to their specific deformity. But you can make this a bioactive brace in a way where we envision the fact that instead of a pigment being patterned, you can pattern things like pharmaceuticals that are either anti-inflammatories or painkillers in these. And just a link back to color is that a lot of the colors we look at in bacteria that are naturally produced aren't just colors. They are multifunctional compounds. For instance, we use something called violaicin, which was collected off a bacteria that grows on the back of this frog in Columbia. And it's also an antifungal on top of the fact that it makes color. Another example is melanin, something that we can readily produce in bacteria and has a lot of protective functions that we have yet to explore. So we'd love to continue to look into the ways in which we can make these valuable circuits in both spatial regulation and maybe temporal regulation. So, we explained a little bit about these displays from the 3D printer Nikolai. A few things, or one big problem with this is that the 3D printer this uses is actually pretty expensive. It's very hard for any person to acquire one of these. So I wanted to talk a little bit about flores in the past where I've tried to do biological hacks on things that are much more accessible. One of my longtime projects is using pregnancy tests. And I can actually, if you come up to me afterward, I can explain this in much more detail. I have one that I've broken open here so you can reverse engineer it. These are amazing kind of boolean tests for the biological world. What we've done to work on these is use bacteriophage and just add them to pregnancy tests in a way that you can bootstrap it and use it for the detection of other bacteria and chemicals in your environment. These cost about $1 when you buy them and bulk up the dollar store and they cost about $12 in Las Vegas. So, it does use something about this place. And finally, I want to talk a little about an ongoing project we're doing with fabrics where we actually just pull out the protein producing machinery from a cell. These are called cell-free systems. And we put that within the core of a fabric. It's no longer living but it is still active and we're very curious about the ways in which the processes of weaving and how that organizes material can start to change which things get expressed, what kind of proteins get expressed throughout the structure of a fabric. So, I'd love to tell you guys a little bit more about that too on the side. But in conclusion, we've come a long way with materials. We have a long way to go. I'd like to talk really fast about adoption to say that when you actually hand somebody one of these objects, they really do act a little weird about it. This is a picture of the masks. They went off to the London Design Museum and the Victoria Museum in Australia. And it actually took a lot of convincing from an art museum to have these masks in a place where they're exposed to the public. Genetically modified organisms are still something that we try to get the public comfortable with. And I must say, when we transported them there in a duffel bag, we may have decided that it would be easier to tell people they were salad bowls than what they actually are. These ones are completely pasteurized so there's no living materials left. But it's also going to be a very long and interesting road to understand the policy that's involved in getting these things into our everyday objects. And with that, I'd like to say thank you to all of you and thank you to the team that has helped put these together. And I'll open it up for questions. You got a question here? Anywhere. Hey, great talk. I was wondering if you could comment a little bit about the kind of stochastic nature sometimes of higher order biological systems, especially eukaryotic organisms. Have you struggled at all working with those organisms as opposed to just model systems like E. coli as far as managing determinism and the stochasticity of these systems? Great. Yes. That's a great question. Actually a lot of scientists because tissue engineering is a more established field would like to see these things in mammalian cells or eukaryotic cells. I think one of the reasons that we work with bacteria is to have more predictability in them and less of this stochastic behavior because these things are extremely complicated and the genomes of bacteria are a fraction of the size of mammalian cells and they're very trackable. So, we have a lot more control over what happens and also a huge library of things people have already built out of circuits like state machines, oscillators and all these things. Yeah. What other sort of chemicals have you pregnancy test? Great. So the pregnancy test so far, the main thing we were detecting was actually E. coli, hemorrhagic E. coli, a very specific strain of it, listeria and salmonella. So, you can tell that's actually for the food industry but we looked at different ways to use it for the bacteria that creates whooping cough and a few other things. Yeah. Sorry. Go for it. So, curious question. I know you might not be here yet but for anything that uses biological material on top of regular material but requires structural integrity to be maintained, have you guys thought about immune responses to any external thing? And like if the cell dies or the living part of the structure dies, if there's a failsafe that prevents any structural integrity from being marred or other things like that? Yeah. So I guess there's almost two questions wrapped up in there for structural integrity of the material. I guess one of the main things we did in this platform that's different than what exists is most 3D printing platforms with bacteria put the bacteria in the extrusion. And that means that whatever material is extruded by the printer has to be something that is not toxic to the cell. And a lot of times you're limited in that case to hydrogels by printing the material first and then adding the bacteria later you kind of keep the structural integrity for the most part of the material. But then you also talked about kind of an immune response if you were to like put this against your body and nope, yes, no. When you had the robot that had a brat heart muscle in it. Yeah. If that fails then because it's being attacked by some other organism, does it have a response design into it? Or does it have a failsafe if the intended function doesn't perform what it was intended to do? That's a great question. I honestly don't know how that would respond under these like varying environmental circumstances. And our materials too, we've never really developed them outside the lab to see how the colors would be more unpredictable in those circumstances. So that would be kind of a challenge about the biological and the material properties to see how we can make these things more failsafe or keep the hydration or the humidity in and all these things was definitely, yeah. Okay, wrapping up, I can get your question after but thanks so much everybody. Thank you. Thank you.