Episode 70: Dr. Matthew Hartings on 3D Printing Materials & Food Science

Introduction to the chemistry podcast

0:00Hi, you're listening to Let's Talk Chemistry, a podcast by ChemTalk. On today's episode, we're joined by Dr. Matthew Hardings, professor of chemistry at American University. Dr. Hardings leads a research group aimed at creating new materials through 3D printing and by studying biomineralization. Dr. Hardings also bridges the world of chemistry to everyday life through food, exploring the science behind cooking and sharing some surprising yet simple ways to elevate a meal.

0:33We hope you enjoy.

0:43Hello, everyone, and welcome back to another episode of Let's Talk Chemistry. My name is Porvi. I'm Elizabeth. And I'm Michael. Today we'll be exploring our interview with Dr. Matthew Hardings, a materials chemist and food scientist who works on developing new materials for 3D printing and using biomineralization to infuse structures with nanoparticles. Before getting to the interview, though, let's hear a little bit of background first. Michael, you mentioned Dr. Hardings researches biomineralization. What exactly is that?

Explaining the science of biomineralization

1:18Great question. Biomineralization is the process through which living organisms produce minerals, and it is critical to evolution, development, and biological growth. During biomineralization, minerals are deposited in a highly regulated manner, leading to the formation of carbonates in invertebrates and silicates in diatoms and algae. Exactly. Some common structures that are formed by biomineralization include bones, teeth, and shells. This very process inspired Dr. Hardings and his team to explore the possibility

1:52of infusing protein-covered nanoarticles into preformed structures or structures that are being formed during biomineralization. This is super exciting. This thing can potentially lead to the production of new materials. Thanks for explaining that. Dr. Hardings also works with another unique

3D printing with metal-organic frameworks

2:09way to produce new materials, which is by 3D printing. You may have seen or even used a 3D printer before, but 3D printing isn't just limited to making things like plastic models or prototypes. In chemistry research, scientists can use specifically designed materials to create structures with specific chemical properties. One class of materials that works particularly well for this is metal-organic frameworks, or MOFs. That's right. MOFs are a class of solid, porous materials consisting of metal ions or metallic

2:45clusters linked together by organic molecules. They have high thermal stability, large surface areas, immense porosity, and chemical versatility. And all of these amazing properties are what earned the first developers of MOFs the 2025 Nobel Prize. Yes, it is a highly versatile and amazing material. It's helpful in 3D printing in particular because in order of the 3D print chemically reactive materials, an analyte, which is a specific chemical substance that is being measured, analyzed, and such or tested, must diffuse to the desired location of the reaction.

3:20In addition, the final product should be naturally porous. MOFs' properties help achieve both of those goals. However, porosity is not ideal in regular 3D printing. In those cases, the desired result should generally have smooth and homogenous structures without gaps. High porosity can weaken mechanical properties, durability, and reliability in regular 3D printing. So Dr. Hardings has had to look into new libraries of polymers. Let's listen to Dr. Hardings explain both of these methods for

Meeting chemist Matthew Hardings

3:54developing new materials. Welcome to Let's Talk Chemistry podcast, Dr. Hardings. Thank you so much for joining us. Could you start by introducing yourself and telling us a little bit about what you do? Sure. Thank you for having me. My name is Matt Hardings and I am a professor of chemistry at American University. I do a number of things in lab. I do lots of food chemistry research based on

4:24based around flavor. And I also do a lot of research on 3D printing and designing new materials for 3D printing. Awesome. Thank you for that introduction. And to start us off, could you tell us a little bit about what initially drew you into chemistry? Sure. So what initially drew me into chemistry? I think there's probably lots of things. There's lots of things that go into my origin story as a chemist. But I think what really cemented all of that is my mom was a high school science teacher.

4:58And she taught both in high school and she taught at a community college too. And I remember, so I'm the oldest of three kids. And so when she had us, she stopped working for a bit while she was taking care of us because we were so tiny. And then when she went back to work, that's when she taught at a community college. And she had her own lab at a community college with all sorts of fun toys and things and like all these drawers that had these amazing things. And then we would just like

5:28rifle through and play with and we probably shouldn't have. But really probably because of my because of my mom. And, you know, I've had great science teachers all the way through sort of grade school to high school and obviously college and beyond. So that helps a lot. But certainly it started with my mom. Thank you so much. That is so interesting. Could you discuss your educational

Navigating an academic career path

5:53journey from researching bee venom biophysics at Caltech to biome for painting and food chemistry at American University? The journey is real. It is very winding. And I don't think you can really predict at all where it's going to go. If if I had tried to predict this when I was an undergraduate and I knew I kind of knew I wanted to go to graduate school, I had done an internship. So I started off at

6:29the University of Dayton, I should say, in Ohio, little town in Ohio. So I started off at the University of Dayton. While I was there, I did an internship at Sandia National Laboratories. And while I was at Sandia, I really figured out that if I wanted to be in control of my projects, that I had to get a PhD. I kind of watched all the people around me. And, you know, I saw you could do lots of cool things after you're done with your undergrad. There were lots of people with just BS degrees at

7:00Sandia doing amazing things. But the people in charge making the decisions and really getting to put their there a lot more of their influence on the on the science that was done, they were all PhDs. So, you know, I didn't come from a big background where I knew any of this stuff beforehand. And so that was really when I figured out, well, I got to get a PhD if I want to really, you know, sort of oversee what I'm doing. If I want to have a larger role in deciding what kind of chemistry goes on, I got to do a PhD. So I was fortunate enough to go to Northwestern and I had

7:34some wonderful mentors and advisors while I was at Northwestern. Tom Mead, who is still there, and Mark Ratner, who just passed away a couple of weeks ago. Both are amazing, amazing people and really supportive of me in that journey. And so I had a great time at Northwestern and sort of I was varied there as well, right? I did some work on protein structure and protein structure. In the

8:05gas phase, I was doing some mass spec work. So looking at the shapes protein take when there's no solvent around, that was really interesting. Then that turned into electron transfer in proteins. And after that, that electron transfer in proteins is what then took me to Caltech to work with Harry Gray, who was very famous for studying electron transfer. And really, Harry and the group there

8:36and Jay Winkler, who's worked with Harry for many years, have really defined our understanding of how electrons move through proteins. So it's really a great place to go to work. But when I got there, Harry and Jay said, well, we've got this problem that we want to we want to work on looking at membrane proteins and membrane protein structure. Okay, let's do that. And so that was where the B venom stuff came from. So I started studying B venom with them and using lasers to look at fluorescence to understand how the where the where this little B venom peptide was in a cell membrane, we could use

9:13the fluorescent reporters that were in in B venom for that. So it, you know, again, a journey. When I moved to AU, though, right, so there's a big difference in going from two really big chemistry programs with lots of graduate students, lots of postdocs, and lots of undergrads, all kind of working with with their PI to now, I'm at AU. And American University is great. I love my time here. But what is what is different about AU is I am solely working with undergraduate students every now

9:48and then I have a master's student that that works with me, but really 90%, 95% of the students that I've worked with are undergraduates. And you guys know this too, in your schedule, you have a limited amount of time where you can go into lab, right? You've got your class schedules. And so if you want to make it into lab during the semester, you've got to have a block of time that cuts out from your all the all the courses you've got to take to go do do something significant in in the lab. And and I had

10:21plans for when I started at American for the type of research I wanted to do. And those plans shifted based on the reality of doing intensive work with just undergraduate students. So we had to find projects that we could not necessarily piecemeal, but be able to leave and come back at different times during the day and during the week, and still be successful at that. Some of some of my ideas going in, like, you were, you had to set your schedule around what the science was telling you to do,

10:57and what your your synthesis was doing, or what your prep was doing. And that wasn't going to work the way that things operate a when it, you know, that's, that's fine. I really enjoy working with undergraduate students, I really enjoy the training that goes on with that the one on one interactions that we get, and really helping to shape these amazing young professionals at the start of their careers. Anyway, so I should say, right, you did ask how I got to food chemistry and 3d printing and

11:29stuff like that. So the 3d printing we started doing when, so I had done some biomineralization work looking at how proteins and metals interact with one another to make nanoparticles and stabilize those nanoparticles. I wanted to start. And so in doing that, right, that was sort of it, when 3d printing really got big. And I thought, well, that's really fascinating stuff. 3d printing is really cool. But you print something and then it sits on your desk. I wanted to see, can we print something that does

12:03interesting chemistry. And so we took some of the biomineralization work and looking at nanoparticles and tried to figure out what kind of nanoparticles could we put into 3d printing materials to then have them do interesting chemistry after you print. So that's, that's part of it. The food, the food science is a different, slightly different route. When I started it at American, they wanted me to teach a class called like chemistry in the world, right? It's like, here's a polymer. Polymers are important. Here's fluoride. Fluoride is important. Like, you know, one of those classes to

12:34an intro class for non-science majors. And I said, well, all that stuff is, is great, but it sounds super boring. Can I teach a class on food science and food chemistry? And they said, sure, go right ahead. Um, and so there was no textbook for anything for it, uh, nothing like that. So I kind of had to make up the class as I went along. And that probably wasn't the best idea, although it has served my career very well. Um, that's had a lot of legs for me. Um, so I've done lots of work in food chemistry,

13:04both in terms of, of teaching, um, external facing communication, like you all are doing now here. Um, really food is a great mediator for talking about tricky chemistry to people who don't normally want to think about chemistry. Um, and, and so now I'm doing laboratory research with chemistry with, with food chemistry too, mostly around looking at flavors, but I am also on a big, uh, NSF funded project where we are studying the causes of food waste.

13:34And trying to understand how to minimize food waste in our world. So, sorry, that was very

Storing hydrogen and altering polymers

13:40long and rambly. I apologize for that. That was a great journey. It seems like you've had a lot of, you've had a lot of experience in a lot of different areas in terms of 3d printing. You've said in the past that there's been an effort to generate materials that are capable of storing more hydrogen. And you've worked with the metal organic framework materials, um, in other terms, MOFs, and you printed composites of acrylonit, nitrile, butadiene, styrene, so the ABS.

14:13Why was it important to alter the hydrogen storing property of these polymers while keeping other components constant? Um, okay. So I have MOFs are really interesting materials, right? So MOFs won the Nobel prize. What was that two years ago for chemistry? Um, and, and so they've got all this great promise, um, for the amounts, uh, for their, their high surface areas on, on their interiors for the potentially interesting chemistry you can do within those internal surface and that internal surface

14:47area. And gas storage is one of the, the big ones. Um, one of the issues with MOFs in general is that when you synthesize them off, it's a powder and okay, that's fine. That's good. Uh, there are lots of things you can do with powders. You can pack a bed of, of powder, right? You can put it into some container, compress it so that there's lots of powder in that, and then, you know, flow gas through it or whatever. Um, but powder on its own is hard to incorporate into a device. So if you want

15:23to make, um, if you want to make a, a filter for, for selecting one kind of gas to flow through and you want to incorporate that into an already built part, powders are tough. It's really tricky. Um, and so our idea, our idea behind that is, well, if, if we can incorporate these MOFs into polymers and, and keep some of that MOF property, then we can process the polymer MOF composite into all sorts

15:59of shapes that can go into ready-made things, things that are, are, are already in use. And, and so we can, we can make filters, 3D print filters, or we can 3D print, print, uh, gas flow beds or chambers or other things like that. You know, that, that's, that was the grand idea. Um, and so our start, right? So we started with ABS. So acrylonitrile, butadiene, styrene, ABS is what they make Legos out of. Um, it's also one of the, the, the main 3D printing polymers that's sold on the market along

16:29with, uh, polylactic acid or PLA. Um, and so what we did was we just took MOF powder that we had synthesized and we did milk blend with the 3D printing polymers. We, we got little pellets of, of ABS and we blended them together and we found ways to do that in which the MOF would still be active after you printed it. Um, that project in general has a couple, there are a couple issues there, right? So we were able to successfully print these 3D, these 3D printed MOF polymer composites.

17:05The MOF still acted as they, as they would otherwise. Um, but one of the problems with it is that the adsorption of gas into those MOF particles is slow because you've got all this polymer around it and it just slows the diffusion of gases from outside of that into where the MOFs are. And so that was a problem. Um, the other problem was, is, is that to make this, these things 3D printable, um, we had to lower the amount of MOF that you actually put into a 3D printing polymer.

17:41So the largest loading we ever got was 25%. And so if you think about, right, so with MOFs, one of the things you go for is, is the amount of gas you can store per gram of material. And so if your total gram of material that you're using now is both MOF and polymer and, oh wait, your MOF is now a quarter of that, you've cut that adsorption capacity by, by a quarter, right? So you've divided it by four. So that's, that's not great either. Um, there was one group,

18:11um, I think at Pacific Northwest that ended up printing something that was 50%, which is pretty, pretty awesome. Right. And you can imagine too, right? If, if you've seen 3D printers, there's these nice, beautiful filaments and they go through the print nozzle and they got to come out and they got to hold their shape. As you start throwing material into that polymer, into that filament, um, it's printing properties are go get worse and worse and worse the more you add. Um, and, and so while it's interesting, there are issues there. And, and so one of the things we're

18:46actually currently working on, um, is a way to print, um, to print a precursor to a MOF at a really high loading percentage. Um, right now we're working with materials that are, uh, after you, so we have a, so if we start with a zinc oxide and a polymer, right, we can, there's a, there are chemistries where you can take zinc oxide nanoparticles and convert that into MOF, into different kinds of MOF. There are different conversions for doing that. Um, but if you start with the MOF, the zinc oxide in your

19:22polymer at 50%, right? So even loading capacity, by the time you convert your zinc oxide into the MOF, just by the mass balance and doing all your stoichiometry and all that stuff, you actually get 98% loading because you gain so much mass from incorporating the organic ligands that go into the MOF, uh, expanding everything. So you can really kind of push the boundaries of what you can do. So

19:52we are, we are evaluating a number of ways to do these prints and that's kind of where the project is

Embedding chemical properties into prints

19:57right now. That sounds like an awesome project. Thank you. For one final 3d printing question, we've know that you've mentioned embedding chemical properties into these 3d printed objects, the same way a pigment may get printed onto them. Could you talk about this work and what's the hardest part of getting a chemical property as opposed to a pigment to survive the printing process? Yeah. So I think the biggest issue is, is like I said before, it's accessibility of your reactive species, whatever

20:32that is, right? So for a pigment, you just got to be able to see it, right? If your polymer is, is clear, transparent, even if it, it has some little bit of color in it, if you load it with enough dye and you don't need a really high concentration, you can see it with your eye, right? Light shines on it, it absorbs, you get some reflected light back. That's all you need with the, um, with any sort of reactivity, your analyte has to be able to diffuse through to where you want that reaction to happen.

21:04And so that's one of the tricky things. Um, what's, what's kind of really interesting about that is in regular 3d printing, you're used, right? If you use a filament and you melt it and it forms a shape on a surface, you want really smooth, uh, really homogeneous sort of, um, structures forming, right? You want the filament that comes out, right? What you print out of the nozzle to be nice and even, to not have any gaps, to not be porous. And that is not the case for what we are doing. Um,

21:40in fact, we want, we want things that when they print are naturally porous that aren't necessarily, that are strong enough to hold its shape, but they don't need to look pretty. And so there's a whole bunch of other sort of polymers that are open to us because of that. Um, but it makes it hard to search through new libraries of polymers, um, for things that I haven't worked in the 3d printing industry because people have tried those, but then they don't often say, well, we tried this

22:12when it didn't work for this reason, right? They show us what works and we know what works, but, um, we often like in, in the, in the science publishing world, we don't talk necessarily about what experiments don't work. And, and in the industrial world and the business world, they're going to show you their products that work great. And they're not going to talk about all the things that they tried, which they did try, right? They, people are trying lots of different things, but they're not going to tell you about the things that didn't work at all. And so it's hard to then go back through, all right, let me try this. Let me try that. That's,

22:44it's a lot of different permutations to try to go through.

22:49Understood. That does sound like a difficult process trying to make sure everything works out the way we wanted to work out. A final question for you before we turn it over is you've

Comparing synthesis to biological growth

23:00discussed your interest in biomineralization. And some of your work explains growth of gold nanoparticles using proteins like bovine, serum albumin, or BSA. What does a biological process like that let you build that conventional chemical syntheses do not? Yeah, that's a great question. Um, so our biomineralization, right, is that sort of in, in sort of fake name only, right? So we're using gold, uh, we're gold ion. So gold three plus,

23:34um, with BSA, um, and, and looking at how those form nanoparticles, but also how the composite, then the, the protein coated nanoparticles could then incorporate into larger materials. And that's, that's the big thing is how do you get these nanoparticles to infuse themselves into either preformed structures or structures that are being formed during the biomineralization process. And the way our bones form is a really interesting take on that, right? So bones are mostly made of

24:12cartilage, right? All that, that good, um, halogen that makes up our cartilage is really what our bones are made of. And, and what is it? 70% or so is just protein. Um, and nature has figured out and evolution has figured out a way to incorporate, um, hydroxyapatite, right? So all of these, these calcium particles and platelets into our, into the, the collagen of, of forming bone.

24:43And so that process is really neat because if you just tried to make a, a calcium nanoparticle, a calcium hydroxyapatite nanoparticle, it's not just going to go into collagen on its own. There has to be something that carries it into the growing, forming bone, and then allows it to align itself in such a way to organize itself, uh, you know, organize all the nanoparticles in such a way to give that bone, the tensile strength that needs the, the red, the flexal, the flexural strength

25:16that needs the compressive strength that it needs. Um, so there's lots of not necessarily just particle synthesis, whether that's nanoparticles or microparticles, and it's not just the proteins that then carry those nanoparticles into the, the collagen that's there. All of these things kind of work together with one another. And there's some really interesting kinetics that, that allow this stuff to happen too. And this formation process,

25:48um, none of these things are static. It's in that growth process that all of these things find ways to work with each other to make this thing. And so that's, what's really fascinating about it to me is, is that it's these controlled, intricate chemical kinetic processes that ultimately dictate sort of what my teeth are like, or what, you know, what my jawbone is like, or, or whatever the case may be. Um, and so trying to sort of get at that piece by piece and, and seeing if we can take advantage

26:21of some of those same kinetic processes and making other materials that we haven't, we haven't explored

Exploring the everyday chemistry of cooking

26:27yet is really is, is what fascinates me. Awesome. Thank you so much. Um, I think we'll take a little second to transition over to the food chemistry aspect of your work in this interview. I have already talked a little bit about how you actually teach a course, um, about the chemistry of cooking. What is maybe the one piece of chemistry that you find yourself explaining the most often, or maybe even a recipe from your book, um, or course that is the most fascinating to you?

26:58Um, well, so people are always asking about nutrition and, and so, um, I'm going to hedge all of those, right? Because all of my students, whenever they come into class, there's always nutrition stuff that's in the headlines. Um, I had a student, we were, I had a student last year, we were talking about, um, we're talking about different kinds of flour. So pastry flour, um, all purpose flour, uh, bread flour, and talking about the different protein content in all of those and how that protein content allows you to, you know, make bread or make croissants or,

27:31or whatever the case may be. Um, and, and so, you know, the student asked me, you know, is the bread flour healthier because it has more protein in it? No, no. Like, you know, protein is having a moment now is what I said. Um, but like, I always get lots of questions about nutrition and, and really, you know, it all comes back to eat lots of everything, right? Have a balanced diet, all of that stuff. Um, I think what is most interesting to me,

28:02and, and maybe we got to that a little bit in the biomineralization question, um, with cooking, you are so well served by taking your time, organizing early, maybe starting your prep the night before.

28:25Both texture and flavor are served by that in really, really fascinating ways. Um, I think one of the, one of the big things that I do, that we do at home. So there's a recipe, um, from a restaurant in California called, uh, Zuni Kitchen, and they have a, a roasted chicken recipe. And, and so my wife is the best at making that. So she makes it, I make it every now and then, but she's, she's better at

28:55it than me. So she, she gets to make it. Um, but that one, you, you salt your chicken, right? So you, you season, right? You season your, your, your food, but you salt that chicken two days in advance before you do anything. And, and so there's no time difference, right? If you're just prepping at the day of to roast a chicken, you're going to salt it. You're going to do all these things anyway. Um, but if you salt it in advance, the skin dries out and gets crispy as you bake it.

29:25Um, and, and all of that salt permeates through your chicken so that, um, again, the, the skin has good flavor. The chicken itself actually gets more tender because of the way the salt iron, the ions in the salt interact with the, the muscles, the proteins in the muscles. Um, so salting early is one example of how doing some of your prep early, even though it takes the same amount of time, if you do it early, the benefits are just astounding. Um, and I, even cookies are the same

30:00way, right? If you were making cookies at home, if you make your dough, your batter the night before, just pop it in the fridge and then bake them the next day. They're better. The flavor is different. The texture is a little bit different. Um, letting your, letting your food rest after you seize it, prep it, seize it, season it, prep it, whatever, um, is really a key to amazing cooking that a lot of us in our very busy days don't want to use. Don't think of using, you know, it's hard to be

30:33that organized sometimes, but when you know that there's something that you want to make a little prep beforehand goes, goes a real long way. That is awesome. And you talked a little bit about cookies specifically. So what actually happens chemically as a food or beverage, you know, flavor evolves. Damn. So part of it is in how some of the, uh, it's so tricky with food. What, what I tell my students is that in the kitchen, your chemistry gets super tricky real fast.

31:11When I'm working in my lab, if you guys are working in labs at Georgia, that chemistry is simple in that you mix two things together and you know, what's going to come out at the end and, and you design your reactions that you do so that you get 90% yield, you get 98% yield. That doesn't happen in the kitchen. There's no, like there are a million different things interacting with one another in, in your batter and you're in these systems. And so there's lots

31:44of stuff going on. Um, part of it is how the, the sugar molecules migrate around, interact with the, the flour proteins, interact with the egg proteins. If that's what you go, you've got going on. Um, it's about how the, the fats and the butter separate themselves into the batter as well. If you just mix your batter and start baking right away, your, your butter is mostly melted. And so because it's mostly melted already, your cookies are going to set differently than if your

32:16butter is still a solid, if you take it and put it in the fridge, so that butter solidifies so that when you start baking it, it takes a little bit of time for that butter, butter to melt as your batter starts to set the, you get completely different results. And I think the, the butter is a good one. And that one you can change just by letting your dough rest for an hour after you're done mixing it. Um, so there are lots of different things that going on that are going on, um, with the flavor. It's really about migration of all of your ingredients, diffusion so that they're evenly mixed.

32:51There are just different chemistries that are available to them, um, when they are well separated and well mixed.

Tackling the crisis of food waste

33:02Awesome. And we understand that you work with an organization called the Recipes Network. Um, how does chemistry actually fit in to a problem like food waste? And I know you talked a little bit about this earlier, whereas most people might immediately feel like maybe a logistics or a policy issue. So let's, let me, let me start at the beginning with this, because food waste is a really important subject for many different things. In the US, we waste 40% of the food that is produced here.

33:34So it is an astounding number. And that is that 40% is food that is never eaten. We buy it, it goes bad, or it goes bad on shelves, or it goes bad on the farm, it goes bad in process. 40%. It's a huge number. And, and we have so many people in the US who are living in food insecurity, who live without the food that they need. And so it is unconscionable that all of this food goes to waste while people get, while people are hungry. So 40% is just a huge number. It's, it's bad,

34:07right? Morally, ethically, it's, it's horrible. It's terrible. So, um, along with that really important part of it, um, when we throw food away and it goes into landfill instead of into, um, composting or to green waste or, or whatever, if it goes into landfill, um, that is likely to decompose into methane. And so methane is a stronger greenhouse gas than carbon dioxide. And there's some number I'm going to say this wrong. It's either 60 or 70% of the methane

34:44that is produced in landfills comes from food that we throw away. So if a landfill is making methane and they all do, they've got little vents on them. Some of them, they, they light those events on fire to burn the methane as it's coming out. Um, if a, if a landfill is producing methane, it's likely that the source of that is our thrown away food. And so there are sort of environmental reasons why we want to minimize our food waste as well, or divert it to different pathways. Um, so this team

35:16that I work on, right, there are 17 institutions across the U S um, you know, 50, some, um, 50, some researchers who are in, um, uh, permanent positions at their research and institutions, lots of graduate students, lots of undergrads, um, lots of other researchers who are, or, um, accessory along with what we do. Um, but the, we range from chemists like me, there are engineers, there are engineers who specifically work on transportation issues. They're mathematicians who work on modeling how food

35:52flows from one place to another. We have people who work on ag policy. We have people who work with, um, with local citizen groups on food rescue. Uh, we have people who work with large grocery stores to figure out, well, how do we capture food before it goes bad on the shelves to get it where it needs to go, right? You're not going to sell it. You know, you're not going to sell it. How do we get it from there to people who need it? And how can we do this in a way that benefits you? Um, so it's a huge broad sprawling team and we all have really different roles. Um, and, and again,

36:28none of those roles are more important than the other. Uh, my small part that I play in that is really thinking about how do we take food at the end of its life, at the end of its edible life, and then come up with something useful to do with it, right? So that it's not going into landfill. And, and we do, we evaluate, um, we do evaluate composting. We evaluate a process called anaerobic digestion, which you take all of your food waste, put it in a huge bin, um, and, and throw some

36:58microbes at it. And those microbes spit out methane and, and other things too, but you capture the methane from, from that and can use it for, for other things that you might want. Um, it's, it's a process called valorization. How do you take this waste material and then turn it into something that is of value to people? Um, we live in a very capitalistic society. And so we need to find ways to put value into things or find value from things that wouldn't otherwise be used. If we want to convince people on mass to, all right, we need to take up this, this larger scheme to, you know,

37:35reduce food waste to, to move it into this process. Um, so that we reduce greenhouse gas. And oh, by the way, your municipality will make X number of dollars from doing it, right? So there are arguments that you can make that people respond to because of that. Um, and so we are, we are looking for ways to valorize wasted food products. And, and part of what I do too, that gets back to some of the other work that we talked about is, is I'm looking at, at wasted food streams from different specific kinds of food manufacturers to see, can we now design

38:09new materials from that, that we can use for packaging that we can use for other things, right? What, what functional materials can we make from all of this wasted food stuff that you've got here? Thank you. We are now going to transition to just some forward looking and concluding questions.

Defending journalistic independence in science

38:31Okay. So you've served on the chemical and engineering news's advisory board and helped organize an open letter about the magazine's editorial independence. Yes. How excited. Why was that issue or science journalism inside a scientific society so important to you? Yeah. So I feel very strongly about, um, a couple of things in this and where, where this is concerned. The first is that CNE news, um, is I have, do you guys read CNE news?

39:06Are you ACS members? Do you get CNE news to, to look through it and read it? It is for ACS members. I think it is the most important member benefit that we have as ACS members. Um, the journalists who work for CNE news, uh, cover both the chemicals, chemical industry, chemical research, uh, jobs, futures, other things that are important to us as professional chemists and do so in a way that is honest with us. That shows us broadly what's going on in our

39:37chemistry world, uh, to, to allow us to see things that are happening while we're focused on our day jobs. It is always good to see the health of our profession. Um, what's happening where and, and things like that. And so there was a change that had started to be made at CNE news that involved, um, removing the current that at the time, the editor in chief and the managing editor had, had just moved to a new job. And, and so there was talk of CNE news losing their editorial independence.

40:18Now the ACS in general, right, operates from our user fees, right? So our, our dues, our membership dues that we pay. Um, but that's not the primary source of revenue in the ACS. The primary source of the re of revenue in the American chemical society comes from chemical abstract at chemical abstracting services or CAS and also from ACS publications, right? Which publishes all of the research journals that we try to publish in and read and do great work.

40:50There is a lot of money that flows into the society in general because of those. And the threat there was that the, some of the leaders of, of the chemical abstracting services and the journals were going to have more oversight over what was happening in CNE news. And so they would be able to dictate. And that was the concern. They would be able to dictate what CNE news covered. The journalists and the editorial staff at the magazine wouldn't figure out on

41:24their own independently what is important for us to cover and how do we cover it. They would be told, this is how you're going to cover this or this is. And so that fundamentally does not serve the members of the ACS. That, that change would have taken a huge resource away from the members at ACS and, and shifted it into cheerleading for all the work that ACS somehow has their hands in. Whether it was

41:55work that's published by ACS journals or, or the businesses that, that contract with chemical abstracting services. And that's not, that's not what a journalistic outlet should do. And, and so as a member and someone who was on the advisory board, I was very concerned about this. And, and, um, there were several of us who were working very hard and, and, and sort of, there was a lot sort of on the scene that people could

42:31see. There was a lot that we did behind the scenes too, to try to lobby, to prevent these changes, to make sure that ACS kept their, um, journalistic integrity and, and, and whatnot. Um, I, I do want to, to say, and it's, it's hard, like, these are things that I, you know, I didn't really understand how it all worked when I, like, certainly when I was your age. Um, but then even until I started working, like being on the advisory board and seeing how they operate, um, and really the amazing things

43:03that they do, the journalists that the ACS gets at, at Cine News are incredible. They do amazing work. They're super creative and, and it is amazing that we are able to benefit from that. And so I wanted to make sure that we didn't lose that in, in the current generation or future generations as well.

43:24Sorry, another long, rambly answer. No, absolutely. And I think, um, that's amazing. And speaking on that topic of like publication education, you often write, you know, blogs, publish books, and frequently share this approachable knowledge about food science and other chemistry. Um, so what motivated you to really be a steadfast educator alongside your incredibly successful career as a scientist? Well, I mean, I, I think that

43:56that's a long, rambly answer too, like all of these other ones. I don't think I'd planned any of that. Um, certainly, and you know, I talked about my mom earlier and I, you know, I, I do think I learned a lot from her and, and sort of she infused into me a lot of, of sort of my approach and, and enjoying the education part of educating and working with students. And I think that's always been a big part of it, but I also think sort of where our careers take us allow for different opportunities.

44:28Um, again, an American, while I didn't have a huge, like sprawling lab and, and graduate students who were working in lab all the time and like, but I had the ability to do some really fascinating communications work and do some really fascinating education. And, and I would argue that the work that I have done on the communication side of chemistry and talking about that has been more impactful than the research that I get to do in my lab. And, and I'm, I'm really proud of that. And it's

45:04not something that generally as a profession that we tend to reward. Um, and that's not necessarily good for the health of the profession either. Um, you know, we, we tend to reward good laboratory results and, and new discoveries and, and we should, we should be doing that. Those are, those are integral to, to, to how we operate, but the health of, of a profession is also decided on, on how well,

45:36how well we interface with society, with how well we have, how well our, our policy knowledgeable chemists are able to interact with, with politicians and, and their, you know, local politicians, state national politicians. There's lots of things that go into making this whole enterprise that we do, everything that we do successful and for its health. And, and so you need sort of all of those things. Um, and so I'm, I'm really proud of the, the communications work that I've done. I'm really

46:09proud of, um, you know, really, you know, thrilled that I've been able to, you know, talk with fancy journalists at the New York times or NPR or whatever about, about food science and, and silly stuff, because it gets people thinking about chemistry a little bit. And, and again, like you guys are doing now, hooray, fantastic, good job getting people to think about chemistry when maybe they don't necessarily do that. It's a, it's a wonderful thing.

Advice for young and future scientists

46:36Absolutely. And I think that leads us to a perfect, you know, ending question. Um, what piece of advice would you give to a young scientist, you know, listening to this podcast right now? Damn. Um, so I have had lots of changes in my career, right? If you kind of look at it from the outside, we've talked about lots of different things today, right? Like there's no straight line from, from where I started at undergrad to where I am now. There's not even a straight line from where I started as a faculty member at AU to where I am now. And, and so, you know, my, my suggestion for

47:12people who are listening is just keep your eyes open, right? Follow what's interesting, follow what you decide is, is best for you at that moment. And, and just let your passions shine through there. And you can always look back and say, Oh, I should have made this decision there. I, there's none of that. There's none of, there are the decisions that we make and the, and the pathway that we're on. And you're always making the best decision for yourself at the time. And, and even with some forward thinking, right. But follow where your passions are and where your interests are. And, and I think in general society, we suffer when, when people lose their individuality a little bit.

47:48All right. We, we benefit from people being their own individual selves. So go on your path, find what's interesting to you and, and really hold tight to that.

47:59Thank you so much for joining us, Dr. Hardings. We really, really appreciate it. Yeah. And thank you both so much. It is so wonderful to hear Dr. Hardings discuss all of these interesting topics. I absolutely agree with his thoughts on the importance of communication. Through proper communication, we can ensure that a greater number of people are knowledgeable about important subjects and better prepared to make informed decisions, as well as encourage collaboration leading to greater innovation and success.

48:30Yes. Certainly. I also really appreciate his message about reducing food waste. In the U.S., food is the single most common material, landfill and incinerated. So it is essential to find ways to reduce food waste. Dr. Hardings work on solving this issue actually reminds me a bit of our interview with Dr. Benjamin Shao, where he talked about using the nitro oxidation method to extract locked nutrients from any natural waste, like food waste, to produce highly effective fertilizers. That's a good point. In order to solve the world's biggest problems, one solution is generally

49:03insufficient. And by utilizing a variety of different methods, we can have a greater and more diverse impact. Absolutely. Thank you again to Dr. Hardings for joining us and sharing your knowledge with us. And thank you to all of our listeners for tuning in. We'll see you in the next episode of Let's Talk Chemistry. Bye. Thank you for listening to Let's Talk Chemistry, a podcast by ChemTalk. We hope you enjoyed it. For more information on today's episode and countless chemistry resources, please visit our website at www.chemistrytalk.org.