October 21, 2024 • 53 mins
Every day at George Mason University, faculty like assistant professor Jeffrey Moran develop innovative solutions to the world’s grand challenges. And sometimes those grand challenges can have small solutions that come from the most unlikely of places. In this episode of Access to Excellence, join Moran and President Gregory Washington as they discuss the water-cleaning powers of spent coffee grounds, aerosol experiments on the International Space Station, and finding inspiration for innovation in jazz.
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(00:04):
Trailblazers in research,innovators in technology,
and those who simply have a good story:
all make up the fabric thatis George Mason University.
We're taking on the grand challengesthat face our students, graduates,
and higher education is ourmission and our passion.
Hosted by Mason PresidentGregory Washington,
this is the Access to Excellence podcast.
(00:27):
Every day at George Mason University,
our faculty are developinginnovative solutions to the world's
grand challenges.
And the great thing about innovationis that sometimes those grand
challenges can have small solutions thatcome from the most unlikely of places.
Joining me today is someone whoknows quite a bit about finding big
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solutions in small, unlikely places:
like the bottom of his coffee cup.
Jeffrey Moran is an assistant professorin the Department of Mechanical
Engineering and is an affiliatefaculty member in bioengineering.
His research lies inunderstanding and using microscale
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thermofluid transport phenomenato enable new solutions
to fundamental challengesfacing humanity. Jeff,
welcome to the show.
Thank you so much for having me. It'sa pleasure and an honor to be here.
What some of you may not knowis that Professor Moran and I
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have a connection, areally, really strong one.
Uh, your postdoc advisor?
That's correct.
His postdoc advisor at MITwas a former student of mine
back at Ohio State, and so we have a very,
very close connection interms of the work that
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he's actually doing.
I think we actually met before I cameto Mason at one of the cookouts that he
had.
Oh, that, that could verywell, could very well.
I think were,
I think you were visiting Bostonand he had occasional get togethers,
Professor Cullen Buie is his name.
And he actually just made fullprofessor at MIT, you may have seen.
Yeah, I did. Yeah, I did. And I, Iactually have not congratulated him. Yeah.
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So I need to go back and make surehe knows how proud of him I am.
So let's talk a littlebit about your work.
Sure.
So your work is in the field ofmicroscale transport phenomena.
Yeah.
And for those listeners whoare out in the audience,
who could be just inother fields or students,
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can you explain a little bitof what that actually is?
Sure. So transport phenomena is a,
a somewhat wonky term thatbasically means the science
of how stuff goes fromone place to another.
And that sounds broad because it is,
the stuff could beliteral stuff like matter.
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Think about a drop of food coloringspreading in a glass of water.
And if you don't stir the water,
then the food coloring spreadssmoothly and radially outward
in a process called diffusion.It could be something like that,
but the stuff could alsobe something like heat or
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something like electricalcharge, or even fluid motion,
a little vortex or an eddy. Sotransport phenomena, you could argue,
underlie just about everythingthat happens in the universe.
But usually when people use thatterm, they're referring to artificial,
engineered systems.
And I'm really fascinated by thistopic because there are a lot
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of parallels in the way that differenttypes of things are transported from
place to place.
I mentioned the example of foodcoloring spreading in a glass of water.
There's also heat, right?So you could imagine, like,
your stove top in the morning afteryou make coffee in the morning,
you turn the heat on and the temperatureis hot right in the center of the
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burner. And then it spreads radiallyoutward after you turn the heat off.
And it turns out the math that describesthat process is essentially identical
to the math describing thefood coloring: diffusing.
And so it's fascinating froma fundamental perspective,
but it's got lots of applications,
especially in things like the chemicalindustry or in, uh, microfluidics:
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the science of fluid flowthrough small passageway.
And the microscale is just referringto the fact that I like studying these
phenomena at the microscopic level.
And my fascination really derivesfrom the fact that we can see
some really bizarre consequencesof those transport phenomena
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that you would never seeat the macroscopic scale. And we'll get into this,
but these include things like a tiny pieceof platinum connected to a tiny piece
of gold actually propellingitself at the microscale in
hydrogen peroxide. Something you wouldnever see at the macroscopic level.
So that's a bit of a flavor ofwhat transport phenomena refers to.
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Well, that's interesting. So whatdo these phenomena look like?
Yeah. So some of them are visibleto the naked eye, like I was saying,
with the dye spreading in water.
Some of them are invisible or they'reonly visible under a microscope.
Something like moleculesmoving from place to place.
Some of them are completelyinvisible. Like for example,
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my PhD work was studying theseself-propelled particles, right? We're,
and we'll talk a lot aboutthese, but these are tiny rods,
small enough that you need amicroscope to be able to see them.
And what's fascinating about them isthat they actually propel themselves by
pushing an electricalcurrent through the solution.
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So ions are generated on thefront end and consumed on the
back end. And as a consequence of that,
ion motion propulsion is generated.So that's invisible, right?
Because if you were to justlook at it under a microscope,
you would just see the rods zippingaround in the fluid in the presence of
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hydrogen peroxide.
So some of them are visible like thedye spreading in the glass of water.
Some of them are invisible,
like the charges moving their waythrough the solution and ultimately
causing a variety of different forcesto be generated that lead to propulsion.
So it really depends on the typeof transport you're talking about.
So as a young person who'sgotten into this field and
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developing a passion forit, how did that develop?
What connected you to start looking at the
micro and nano scale?
Yeah. So I got into researchlate in my undergraduate days.
I was participating in a programwhere undergraduates could
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be paid to do researchin a professor's lab.
We have an analogous program at Masoncalled the Undergraduate Research Scholars
Program, through which I've mentoredabout nine undergraduate students.
And part of the reason for that is that I,
it was such a valuable experience for me,
and I just had the chance to workfor a professor whose lab focused on
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microfluidics.
As far as how I got intothe self-propelled particles
specifically, that was by accident.
It happened when I went to a master'sthesis defense early in my graduate school
days.
And there was a student who wasdefending his master's thesis.
And the thesis topic was howto manufacture the platinum gold rods I was talking
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about.
And the focus of his work was on moreefficient ways to manufacture them.
But he just happened to mention offhandthat they happened to propel themselves
in water, if you addhydrogen peroxide as a fuel,
and that intrigued me. So Iraised my hand and I said,
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how did they do that exactly? And it
wasn't really his main focus,but he, his explanation,
so he can be forgiven for givinga somewhat arm wavy explanation,
but he basically said, well,we don't really know, but it's,
it has something to do with the flowbeing induced in the fluid near the rod's
surface. And you know, the flow goesbackward and the rod goes forward.
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And I sat back and I thought, Hmm.
So I had the fortune of having athree year fellowship that allowed me
the freedom to pursue whateverI wanted for my thesis work.
So I approached my advisor and told himI was interested in really getting to
the bottom of this. And thateventually became my thesis.
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And you know, this is a very youngfield. It just started in 2004,
and so it's just passing the 20 year mark.
And I've just never been able toshake off this fascination with
how we can make these seeminglyinanimate objects that are not
living in any way moveand do things that mimic
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biological systems at themicroscale. And as an engineer,
I'm especially interested inwhat practical applications these sorts of devices
could have.
So my fascination with this reallyarose from that chance encounter at that
thesis defense. But people have beenthinking about this for a while. You know,
there are classic films like FantasticVoyage from the 1960s where a team of
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scientists shrink their submarine downsmall enough to enter the bloodstream of
a colleague and treat ablood clot in his brain.
So people have been thinking about thisand what applications it could have,
ways it could revolutionizemedicine for, for quite a while.
And at Mason,
I'm really trying to marry thatfascination that I still have from my
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graduate school days with a sort ofutilitarian outlook and thinking about
ways that we can start to realize thevision articulated in things like the
Fantastic Voyage film.
So that's a little bit about how myfascination came about. You know,
when I worked for Professor Buie atMIT, we were doing different things.
We were working on some differentareas. And when I came to Mason,
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the time came to establishmy own research program.
And so I'm incorporating someof what I did in my postdoc,
but my focus is really on using theseself-propelled particles to benefit
various different societal applications.
Well, let's talk about that.
Because that is what is soincredibly fascinating. Mm-Hmm.
So earlier this year,
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members of your lab made the news withthe invention of what's being called
the CoffeeBot.
And this is spent coffeegrounds coated in iron oxide
that can absorb pollutants and water.
That's right.
So tell me about how it works.
Sure.
How do they move throughthe water? And then let's,
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let's get into it a little bit.
Yeah. So on that topic, I actuallybrought some visual aids here.
So the, the listeners can't see this,
but I'm holding a vial of what arejust ordinary coffee grounds, right?
And these are coffee grounds Iliterally brought from home and.
Now spent coffee grounds, which means.
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Spent coffee grounds.
Which means they've been used.
That's correct.
That's even better.
That's correct. Yeah. And by one estimate,
we throw away about 23 milliontons of spent coffee waste per
year. Much of that isbeing sent to landfills.
Although increasingly I'm heartenedto see that places like Starbucks
are making just bags of the stuffavailable for folks to use for compost.
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So I've got a vial ofspent coffee grounds here,
and in my other hand I have a magnet.Now, if I hold the magnet up to the vial,
nothing interesting happens.Coffee is not magnetic. However,
if I have another vial here, thesealso look like spent coffee grounds.
They are. But they've been coatedin, as you said, iron oxide,
which is the main chemicalconstituent of rust.
(12:00):
So we sometimes call these rustycoffee grounds because in a real sense,
they are rusty. And if I hold the magnetup, I don't know if you can see, uh,
and for the listeners, the coffee grounds,
once they've been coated inthe iron oxide particles,
they will actually follow the magnet.
So I can make them go wherever Iwant to by holding up a magnet to it.
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So the essence of what wedid was develop a safe and
eco-friendly approach to coating thecoffee grounds with these little tiny
bits of rust. So what does that do forus? Well, it does two important things.
First, it allows us to use a magneticfields. You asked how they move.
It allows us to use a magnetic fieldto drive them through the water.
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So for now, we're just propellingthem with the external magnetic field.
We can come back to that in a second.
We're looking at waysto improve upon that.
And one of the things we demonstratedwas that moving coffee grounds will
actually remove pollutants from watermore efficiently than stationary ones do.
And this makes intuitivesense because, in a sense,
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the moving coffee grounds encountermore pollutants per unit time than
stationary ones do. So we demonstratedthree different pollutant types.
Methylene blue, which is kind of astand-in for a chemical pollutant.
But methylene blue itself isa textile dye that has some
negative health effects,
that is itself a pollutant ofconcern in some areas of the world,
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particularly where textileproduction is common.
Oil spills and microplastics:
those are additionallypollutants of concern.
So both of those are problematic.
Absolutely.
Today. Oil spills and microplastics.
So much so fish todayHave an incredibly large
amount of digested microplastics intheir, in their, in their systems.
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And potentially we do too, potentially.
And because there are so many consumerproducts that contain plastic,
they make their ways into waterways,right? And eventually in some areas,
uh, it probably varies significantly.I haven't seen the statistics,
but definitely lots of differentforms of life are consuming these
microplastics. And I wanna say, this isnot my area, but I think we're still,
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as a community, figuring outexactly what the health effects are.
But they're definitely somethingto be concerned about for sure.
So we demonstrated that we canremove each of those three types. Um.
So microplastics...
Mm-Hmm.
oil and methylene blue asa model for a dot--methylene blue is,
is a textile dye. And it'sblue as the name suggests.
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And that was convenient because thenit's very straightforward to monitor
how much of the methylene bluewe've removed at any given time.
Because you can use an instrument thatessentially looks at how much blue light
is being absorbed.
You can use essentially the intensityat a certain wavelength to determine how
much of the dye is left. So it was,
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it was partially out ofconvenience that we chose that.
Hmm. So
reuse of these coffeegrounds was mentioned.
Yeah. Yeah.
So how often can you use them?
Yeah. So that brings me to the secondmajor thing. That the magnetism enables.
So just to recap,
the first thing the magnetism does isit allows us to drive them through the
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water. And that speeds up thepollutant removal process.
The second thing it does is it allows usto take the magnet and pluck the coffee
grounds out of the water afterthe treatment is complete.
What we do next is rinse it off.We can rinse the pollutants off,
and we do still have to disposeof the pollutants elsewhere.
That is a separate issue that is for now,
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tangential to the work that we're doing.
We're mainly focusing onremoving them from the water.
But that is something that you do stillhave to do something with the oil or
with the microplastics.
And that's something that otherresearchers are working on.
So then after you rinse them,
we typically rinse them with anorganic solvent like acetone.
Acetone works pretty well.
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And then you can actuallydrop them back into the water.
And we showed in the journal paperwe published on this that you can
reuse them at least four times with aminimal reduction in pollutant removal
efficiency. So wehaven't gone beyond that.
But based on how well the first fivetrials went, and this is true by the way,
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with each pollutant class, withdyes, oils, and microplastics,
we have reason to believethat you could go further.
So let me get this straight 'cause Iwant to make sure that the folk out there
see the depth and theprofoundness of what you
are stating.Spent
coffee grounds coatedand iron oxide can be
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dropped into, say, an oil spill.
Absolutely.
And the coffee grounds willattach themselves to the oil.
That's right.
You have a process forthen pulling those grounds,
separating those grounds withthe oil on them from the water.
The oil is rinsed offwhere it can be disposed.
You throw the grounds backout to repeat the process.
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And you can do it up to four times.
Five times total. Right. So four reuses.
Four reuses.
So five times total. So five total uses.
That's amazing.
You nailed it. That's exactly right.
And so when you talk about the coffeegrounds attaching themselves to a
pollutant like oil, or microplastic,how long does that take?
Is it an immediate attachment or...
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So that's a good question.
And it's one that we are really workingon answering more systematically,
to really be able tosay, if you have, say,
a section of a river thathas a certain area, say,
an acre,
and you have a rough estimateof how much oil has spilled,
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there's been an oil spilland some X number of liters.
We don't really currently havea number to say definitively,
this is how much coffee you wouldneed for that section of the river.
But much of the testing we've done sofar has been mainly on the size scale of,
you know, a small beaker, asmall container. That's maybe,
maybe a quarter of a liter of water.
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And we can get away withabout 50 milligrams of coffee.
So just enough to sprinklethe coffee bots in a,
a layer that will approximatelysparsely coat that top layer.
And then as you say, the pollutantsattach themselves to the coffee grounds.
Does that happen immediately?
It's not immediate. So itdepends actually on how,
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whether the coffee groundsare moving, first of all.
So if they're stationary by themselves,
the testing we did was on thetimescale of about 40 minutes.
And after 40 minutes withstationary coffee grounds,
some of the pollutanthas been removed. Right?
But if you drive them through thewater, it increases from about 50,
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60% to about 90 to 95% inthe case of methylene blue.
In the case of oilspills and microplastics,
it's on a similar order.
Wow. That's amazing. So...go ahead.
Oh, I was just gonna say, becauseanother question that I've gotten a lot,
and that is a good question,
is what is it that attaches thepollutants to the coffee grounds?
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Right. That's a fair question.And in the case of oil spills,
it has to do with a propertycalled hydrophobicity.
And it means basically, as thename suggests, hydrophobic,
it turns out that the coffee groundsare what we call hydrophobic.
So for folks listening out there, ifyou've ever waxed your car, right?
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And you put some droplets of wateron afterward, it kind of beads up.
Because the wax has renderedthe surface hydrophobic. It
doesn't like water. So whenwater comes in contact with it,
it tries to avoid touching thesurface as much as possible.
So that's why it forms that bead.
And we have some pictures from the paperwhere if you take a bed of spent coffee
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grounds, it does the samething. So why does that matter?
It matters because thingsthat don't like water
tend to like oil.
So the same interactions that causeoil droplets to coalesce together
in say, salad dressing arealso the forces we believe,
and we have good reason to believe,
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that cause oil to glomonto the coffee bots.
And there's some nice videosthat are included with the paper,
and also in the news segment that wasfeatured on Channel 9 news in March of
this process actually happening.
So it looks kind of like the coffeegrounds are kind of soaking up the oil.
Huh. Amazing.
Yeah. And a similar thing we thinkis happening with microplastics,
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because microplastics arealso hydrophobic in general.
So it's a good rule of thumb thathydrophobic things tend to like to
congregate with other hydrophobic things.
Okay. So you know, this is amazing. So
the question that I always havewhen confronted with, you know,
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this is an everyday product.
Sure.
You know, we toss thecoffee grounds all the time.
That's right.
How did you discover such a use outof something that most of us consider
trash?
Yeah. This is where I have togive credit to my group members.
So I had two awesome members ofmy group who have since gone on to
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other things.
It was a postdoc in my groupnamed Amit Kumar Singh.
And at the time, a high schoolsenior named Tarini Basireddy.
Amit is now a professor himselfat a university back in India.
And Tarini is just beginning hersophomore year at Johns Hopkins.
We were trying to figure out aproject for Tarini to work on,
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because she was doing a year longinternship in my lab as part of a,
she was a senior at ThomasJefferson High School.
And they had this program where, um,their seniors can do research internships,
and Mason, quite understandably,
has restrictions on things thatminors can do in the lab. Uh,
so what happened was, you know,
we were thinking about aproject that would involve
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the things that I was interested in onusing particles that move in liquids that
would not involve any particularhazards. And it was one of those, Hey,
what if we tried this kind ofconversations that I've come to love,
I've come to treasure those conversationsbecause they can lead to interesting
things like this. And I should say,
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we are not the first people touse self-propelled or magnetically
propelled nanoparticles ormicroparticles to clean up water.
There have been a variety of differentstudies in that direction already.
The problem is a lot of those arejust proof of concept demonstrations,
that if you have a particle that's madeof maybe a metal or some other toxic
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substance, but if it moves and it'sable to break down pollutants, you know,
people will publish thatand they'll say, look,
we can use propelledparticles to clean up water.
But one of the major focus areasof my lab in general is trying to
engineer these kinds ofparticles from safe materials.
And we were brainstormingone day and one of us said,
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I'm not sure that it was me. I don'tthink it was me. One of us said,
what about coffee as a way todemonstrate water treatment with
active particles?
Yeah. But why would they say coffee?You know what I'm saying? It makes,
absolutely, that's not whatyou would think of when...
Yeah. Well I have, uh...
I mean, I would think of sandbefore I would think of coffee.
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Yeah, absolutely.
You know what I'm saying?
Well, sand is another material that wework with or silicon dioxide. And we'll,
we will get to that in a separateproject. But, you know, my postdoc,
particularly Amit, I used to say,you give him any three materials,
he would figure out a way to make, makea self-propelled particle out of it.
And so he had a previouspaper on using tea buds,
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like bits of tea,
to make nanoparticleantibiofilm treatments.
So things to treat bacterialbiofilms, for example,
which are part of how antibioticresistance comes about.
So it was just one of thoserandom sort of suggestions
that once somebody said it,
we all kind of sat back for aminute and thought about it.
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And it started to make more sense. Becausefirst of all, as we've already said,
coffee is discarded by the millionsof tons every year. It is hydrophobic.
So it, it can pick upother hydrophobic things.
And if you look at a microscopeimage of a coffee ground,
it has this very irregular,
very dense surface where whatI mean is that there's a lot of
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active surface area given thesize of the coffee ground,
which means it can pick up alarge quantity of pollutants relative to its size.
So the answer to the question "whycoffee?" is really three-pronged:
it's hydrophobicity, it's common andit's relatively safe to work with,
and it has a high surface area to volumeratio, which turns out to be important.
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Hmm. That is amazing.
So what do you think a discoverylike this could have on
protecting and preservingwater systems around the globe?
Yeah, I mean,
we certainly hope that it has farreaching impacts in all corners of the
world. There are lots of areas wheretwo things are true at the same time.
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One, there's an urgent lackof clean available water.
Two coffee is produced and orconsumed in large quantities.
An example would be Ethiopia. Ethiopiais facing a water crisis right now,
and they also grow andconsume more coffee,
to my knowledge than anyother country in Africa.
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But there are other countriesas well. Brazil, Vietnam, Peru,
other areas of the world where coffeehas grown and produced and consumed.
But people don't always have accessto clean water. And in many cases,
actually the challenge is notnecessarily lack of water per se.
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It's lack of access tomethods to decontaminate the
water that is already therein ways that don't use,
or that don't require extensiveinfrastructure that is not available to
everybody in the world.
So our hope is that wecan eventually disseminate
this method and enable peoplewho don't have, you know,
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a huge amount of scientific training,
don't necessarily have accessto nano fabrication equipment,
which I have to say a lot ofpeople in my field still rely on to
basically use the materials theyhave available to them and to
make these themselves. And, you know,it could be implemented in the home,
(27:13):
for example, you couldimplement it in just a cup of,
of of water that youwant to decontaminate.
You could envision this beingimplemented on a small boat where there's
a magnet on the back end of the boat.
And so if you wanna clean upan oil spill in a small river,
you can deploy it that way, deploy alarge quantity of these coffee bots,
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and then move the boat along.
And it kind of tugs the bed of coffeebots behind it--in the news segment they
made a nice animation ofwhat this would look like.
Or you can imagine somethinglike sewage treatment ponds.
So in water treatment plants,
they often will just leavesewage to sit and allow the,
all the microbes to break itdown and decompose it over time.
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So you can imagine just,
and you don't even necessarilyneed them to be magnetic,
you just need to put a whole bunchof coffee grounds on the top layer.
And over time it willbreak down the pollute,
or at least we believe itwill absorb, I should say,
absorb the pollutants more efficientlythan just if you left it to decompose
over time.
Huh. Interesting.
Yeah. So there are alot of potential uses.
(28:16):
So we're in the process of, we'veapplied for a patent on this and...
Yeah, you should.
We, we published this work in a scientificjournal a few months ago. Tarini,
now a sophomore in college, is ajoint first author on the paper.
Wow.
And I think when I was her age, I didn'treally even know what research was.
Well, let me make sure,lemme make sure we're clear.
(28:37):
Yeah.
Most high school seniorsdon't get a publication.
Oh yeah.
A first author publication at that. Okay.No, that is, that's really cool. Now,
your previous advisor at
MIT when he was my student. That's wherehe came to me after his freshman year,
he started working with me in my lab.
(28:57):
I remember that.
Yeah. So, so this is, you're,you're keeping that tradition going.
. Yeah.
And that is phenomenal.
Getting started early.
That's exactly right. Yousee where it can turn.
And I hope that you stay in contactwith this young person and that you
help guide her along togoing to grad school.
She has a bright futureahead of her, for sure.
(29:18):
Outstanding. Yeah. So I'mgonna shift gears a little bit.
In August it was announced that youand your colleague at Purdue University
received NSF funding to design astudy for astronauts to conduct on the
International Space Station.
The research aims to betterunderstand thermophoresis, or
(29:39):
the migration of particles inresponse to temperature gradients.
And that can happen with orwithout the influence of gravity.
So as your work mainly focuses withparticles moving through water,
how do you realize that there wasthis a gap in knowledge about how
aerosols might actually migrate inresponse to temperature and that how they
(30:00):
might migrate without gravity.
Mm-Hmm..Yeah. So once again,
this is another example of aproject that originated from just a
very casual, "what if wetried this?" conversation.
So the impetus for this is that theNational Science Foundation has a program
called Transport PhenomenaResearch on the ISS to benefit
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life on Earth. So we invoketransport phenomena again.
And I was telling,
and I I should mention that I've beenobsessed with space since I was a little
kid.
The house I grew up in is still litteredwith drawings of space shuttles and
models of fighter jets andthings like that. It, it was, uh,
one of the major draws for me to getinto engineering in the first place.
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I understand that one.
And so I've actually wanted tobe an astronaut for a long time.
I applied to the astronaut call in2016. Didn't get selected, obviously,
but there's still a part of methat really wants to go to space.
And so I was really interested in thiscall because if I can't go to space
myself, getting to send an experimentup there is kind of the next best thing.
(31:09):
That's exactly right.
So I was talking to my friend andcollaborator, David Warsinger.
We're kind of going through thejunior faculty process together.
We met at MIT when he was a gradstudent, and I was a postdoc.
And I told him about this and hejust offhandedly said something like,
has anyone made a microswimmer that moves in air?
And micro swimmer isanother term for my field.
(31:33):
There are lots of different terms,self-propelled particles, micro motors,
active colloids, things like that.
And initially the questionstruck me as rather odd.
It was not something Itypically think about.
My field is overwhelmingly concernedwith propulsion through liquids
and gels, not air.
But air is a, can be considereda fluid in some sense.
(31:55):
Absolutely. Yeah. So, right.And so it got me thinking,
and I kind of sat back and it was avery similar moment to the moment when,
back in 2008 at the master's defense Imentioned when the guy mentioned that
these particles happen toswim. It's just kind of,
I kind of sat back and thought, huh,that's odd. How might that work?
(32:18):
And so then I got to thinking aboutthe mechanisms that are active in both
liquids and gases. And oneof those is thermophoresis.
So thermophoresis essentially means it's a
phenomenon, it's a transport phenomenonthat happens in liquids and gases.
And it's basically whensmall particles under certain
(32:40):
circumstances, if they arein temperature gradients,
which essentially means thatthe fluid on one side is cold,
the other side is hot,
there is a force that is aresult of transport phenomena.
There is a force that can push theparticle either in the direction of hot
or in the direction of cold.
Oh. So the force works both ways?
(33:02):
It depends.
So it's not always hot. Usuallyit's cold to hot, right?
In liquids, it can be in either direction.
I see.
It depends on the liquid and itdepends on what you add to the liquid.
And I should mention in liquids,
it's not really fully understood exactlywhat causes it to move towards hot or
towards cold. In gases, however,it's more straightforward. In gases,
(33:22):
motion by thermophoresis prettymuch always occurs from hot to cold.
So if you have a particle that's in air,
and the air is hot on oneside and cold on the other,
then the nitrogen and oxygenmolecules on the hot side
are by definition zipping aroundwith more velocity, right?
When they collide with the surface ofthe particle, they impart a force to it.
(33:45):
On the cold side, they'rezipping around with less energy.
So the force that they impartfrom the cold face is less.
And so the end result is thatthere's a net force owing to the more
forceful collisions on the hot sidethat pushes the particle towards cold.
So this is known to happen in gases,but then I got to thinking, okay,
(34:07):
could we then quantify it somehow?
And it's difficult to do on earthbecause of things like gravity,
which will cause the particlesto fall out of the air.
And there's an additional problem withthermophoresis because hot air rises,
right? So if you were to try tohave a sample of particles and air,
and you somehow kept them from fallingto the ground and you heated the air on
(34:31):
one side, it would rise. And thatwould cause the particles to move.
And it would be hard to discern how muchof the particle motion is really due to
thermophoresis in that case.
I see. I see.
So what we realized wasthat in microgravity on the international Space Station,
you don't have thoseconfounding factors, right?
And it would be possible, we think,
(34:54):
to isolate just the componentof thermophoresis that
drives different typesof particles through air.
So why would anybodycare about this? Right.
That was kind of the next question thatwe had while we were thinking about
this. And it turns out that aerosols,
small particles suspended in air,
(35:16):
are very important to ourunderstanding of the global climate.
And they pose a pretty largeamount of uncertainty actually,
in terms of what their neteffect is on the global climate.
Some aerosols actually can exert an
overall cooling effect. Someaerosols warm the planet.
(35:38):
Aerosols are produced byvolcanic eruptions, dust storms,
other natural events like that.
Human activity like burning fossil fuelsalso injects a bunch of aerosol into
the atmosphere.
And so it's a very active area ofresearch in climate science right now.
And so what we're intending todo is take measurements of how
(35:58):
efficiently different aerosolsmove by thermophoresis.
And the hope is to help climatescientists understand how important this
mechanism is in the atmosphere,
because the problem of aerosols inthe atmosphere is only gonna increase.
Rocket launches are anothermajor source of, uh,
space junk that can sometimesbe in the aerosol range. Um,
(36:20):
and it turns out that thisphenomenon, thermophoresis,
is most important at very high altitudes.
Hmm. Interesting.
So that's one part of the project.And the, the swimming part,
the self propulsion partis to look at whether,
instead of say applying heat on oneside and cold on the other side,
looking at just a single particle withhalf of its surface coated in a metal,
(36:43):
something that absorbs light reallyefficiently shining a light on it,
and then seeing if the metal sideabsorbs the light more efficiently
than thus heating up faster, that willthen heat the air surrounding the,
the metal side leading to propulsion.
This is something that's been demonstratedon earth but has never been seen in
air before.
So we call this self-thermophoresisbecause here the particle doesn't require an
(37:08):
external temperature gradient, but itgenerates it itself and then moves.
So we're gonna also see whether thathappens and we call those micro flyers
instead of micro swimmers.
. That is a greatway to describe them. Hey,
so there's a healthcare, uh,spin on this as well, right?
I mean aren't the vectors for carryingdisease, especially Covid, for example,
(37:31):
as carried like an aerosol.
Yep, absolutely.
And so, so you have,
if you can deliver somethingharmful using this mechanism,
you can actually deliversomething helpful.
That's right. That's right.
So I think NASA wouldprobably balk at the idea of
(37:53):
us sending virus-ladenaerosols to the space station.
They might have one ortwo issues with that.
I understand.
But it's a very good point.
And that is an additional applicationwe're interested in because if we
find that thermophoresis indeedis an efficient way to move
aerosols around,
this could suggest anothermethod to collect virus laden
(38:18):
aerosols from say, the HVACsystems of hospitals, right?
Which is obviously a big problem there.
And we're still figuring out exactlywhich aerosol materials we're going to
send. So we launch sometimelikely in the second half of 2025.
And most of the materials we'reinterested in are things like,
(38:40):
I mentioned sand earlier,sulfate aerosols.
These are aerosols that comefrom volcanic eruptions.
They're also geoengineering proposalsto intentionally inject aerosol to cool
the planet. Obviously controversial.Lots of research going on into them.
So we're looking at that (38:56):
sodium chloride, believe it or not, table salt.
Comes from sea spray.
And that can actually drift todifferent parts of the globe.
And that can affect the climate inways that we don't fully understand.
But we're also looking at somethingthat could act as a stand-in for
an aerosol that is produced by say,somebody coughing or somebody sneezing,
(39:18):
and we'll see what we see.But you could easily envision,
and this has somewhat been exploredbefore, but you could envision, say,
having a stream of air where you havethe stream going in one direction,
and then a temperaturegradient perpendicular to the stream of air so that the
particles, the aerosols, ifthey migrate thermophoretically,
(39:39):
they would bend toward the cold side.And just be collected on the cold plate.
So the viability of that, you know,
that is something you could in principletest on the ground, you could test.
On the ground and youcan test that at scale.
Yeah, that's right. So what's gonnahappen is on the space station,
there's actually a microscopeon the space station already.
And so what we're doing isdesigning and building a,
(40:01):
an apparatus to apply thetemperature difference to a series
of different cuvettes--tiny transparentcontainers--that each of which
contains a different particle sample.
And so the ISS crew isgoing to then look at those
different samples, apply thehot and the cold as needed.
(40:22):
We're gonna be able to watch inreal-time as the astronauts perform the
experiments and measurethe migration speeds
of these different aerosolparticles as a function of say,
what type of particle they are, youknow, the temperature difference,
things like that.
As we start to wrap uphere. So what drives you to,
(40:42):
towards this sort of innovative research?
I could sum it up in oneword, which is curiosity.
Hmm. Interesting.
I have in this job as a,
one of my favorite parts of thisjob is that I have the privilege
to
pursue ideas that pique my interestwithout much more of an imperative than
(41:05):
that. Actually, Professor Buie, my mentor,
your protege, he once described itas being an idea entrepreneur. And,
you know, it sounds like him, right?He's, he, he's, he's got a way with words,
with he is a way of coiningthose kinds of phrases.
But I think it captures a lot of whatI love about this job, along with,
of course, working with andteaching and mentoring students.
(41:27):
That's definitely another favoriteportion. But like I said, you know,
both coffee bots and this ISSproject both grew out of just
conversations I was having.That piqued my curiosity.
And because I have this role,
I was able to follow up on that curiosity.And in the case of the ISS project,
(41:48):
write a grant proposal about it thatjust so happened to be funded. And
so I really think curiosity-drivenresearch is a buzzword you hear sometimes.
And I think it's certainly good for doingresearch that is just kind of on the
pure science side that is just, you know,to kind of satisfy our, our curiosity.
But I think it's also a good wayto unexpectedly discover new roots
(42:13):
for applied research, likein the example of coffee.
So I'm a big fan of curiosity.
I think I've been able to work ona really eclectic mix of different
problems as a faculty member frommaking more insulating wetsuits
to the projects that we've beentalking about today to other
(42:33):
projects and collaborations I havethat are more on the medical side where
we're trying to, say, penetrate abacterial biofilm with active particles.
A lot of these really, the impetus forme, really stems from my curiosity.
That's what got me into thisself-propelled particles field in the first place.
Just that I wasn't really satisfied withthe answer that I got in that master's
(42:55):
thesis defense. And, you know,
I was able to just follow upon it and make it my thesis.
So if there's one driving force, it,it would definitely be that just,
I'm just a curious person by nature,
and I have a hard time shaking offquestions that really get under my
skin and that I reallywanna know more about.
No, that's cool. Well, Jeff, there'splenty of room at the bottom.
(43:17):
. That's exactlyright. That's exactly right.
So I often invoke that speech that, uh, there's plenty.
Plenty of room at the bottom.
There is, uh, the, the speechby Richard Feinman in 1959.
Fineman. That's exactly right.
And in that speech, he talks aboutswallowing the surgeon. He said,
there's a friend of his that said it, it,
it would be very interesting in medicineif you could swallow the surgeon that
(43:41):
it goes inside the body and, you know,goes to an organ and looks around.
And actually later in that speech,
he challenged the community to builda tiny motor that fits inside a cube,
1/64th of an inch on its side.And a lot of what we're doing is,
is exactly that, is we'rereally trying. In fact,
we could probably fit muchsmaller than 1/64th of an inch.
(44:02):
Some of the particles we work on aretoo small to even be seen on an optical
microscope. So, well, yeah.There's plenty more to do. Yeah.
That is really cool. Yeah. Um,that's cool for drug delivery.
That's cool. For all typesof treatments for disease.
So really, really cool stuff.
And I should mention, you know, this hasreally grown in the last 20 years to a,
(44:25):
a robust field in its own right.
The first ever startup company thatI'm aware of was founded recently by
a guy in Spain named Samuel Sanchez,
who's kind of one of thesuperstars of the field.
They're looking to develop a bettertreatment for bladder cancer.
Part of it has to do with makingparticles that use enzymes,
nature's catalysts, asthe engines, basically.
(44:48):
And we have some other projects in thelab that use those very same enzymes
partly for, for biofilm eradication orother sorts of applications like that.
So it is growing, and I don'tknow if we're gonna see it,
we're not gonna see it in clinicsin a year or in five years,
or probably not even in 10 years,but maybe in 15 years, right?
There are some fundamental challengesthat we still have to address.
(45:12):
And on the medical side, we haven'treally talked about that today,
but on the medical side, we're reallytrying to address, uh, some of those,
particularly making themfrom safe materials.
That is cool. As a wrap up here,
one of the things that I really,
really like about you isthat your passion is not just
(45:32):
in engineering. It's not just in thesciences. You know, I was happy to see,
uh, one day when we had our jazzmusician quartet at the house
playing music for one of ourevents to say, wait a minute,
that guy looks familiar.
Yep. Yep. That's me.
And so you, and so you moonlightas a freelance jazz musician.
(45:53):
Specializing in the double bass.
That is correct.
So talk a little bit about that,
how long you've been playing the doublebass and what excites you about jazz.
Yeah. Well, I've been playing thebass since I was in sixth grade. So,
quite a while, quite a while.
But I've been entranced by the doublebase for as long as I can remember
(46:14):
since I was about four,
I think I was about four when I startedbegging my parents to get me an upright
bass.
And my mom still has someembarrassing photos of me as like
a 4-year-old wearing atuxedo for Halloween.
I was a conductor tryingto conduct the orchestra,
and I can't really saywhat drew me to the bass.
(46:35):
I still can't really fully explainit. And maybe that's part of a,
a testament to how powerful itis. I just love the way it sounds.
I love the depth,
I love the character of awell-struck double bass string,
a well-plucked double bassstring, you could say.
And so I did piano lessonsas a kid, like many kids do.
(46:55):
Didn't really enjoy themthat much, but it really, it,
it was useful though because I learnedhow to read music that way. And,
you know, also having a prettyrobust interest in math. I,
I saw pretty quickly the parallelsbetween music theory and mathematics.
Okay. So that was gonna beone of my next questions.
(47:16):
Yeah. Yeah. So, butthen in the sixth grade,
I had the chance to take amusic appreciation elective,
and there was one day where they justturned us loose to try out different
instruments and I made a beeline forthe double bass and just haven't really
set it down since. Incollege, in undergrad,
I was briefly for about two years,
(47:38):
a double major in jazz performanceand mechanical engineering.
I ended up just sticking with theengineering major. But during that time,
I had the chance to study with ajazz bass instructor who really
was a fantastic mentor to me, notjust as a musician, but just as a,
as a young adult.
So I think I got what I needed becauseI realized that you don't need a music
(48:01):
degree to play music.
But the same is not exactly true fordoing engineering work professionally.
So college was when I reallystarted to freelance on the bass.
And it ever since has been acreative outlet and it's been
something I've been able tocontinue to do, which I'm really,
really happy about. Um, so, so youasked about jazz. You know, we,
(48:25):
we had jazz records playing in thehouse growing up. I was in, you know,
classical orchestra in high school.
And I still enjoy classical music as well.
But I think part ofwhat drew me to jazz was
it can be very mathematical, it can bevery complex in terms of the harmonies.
(48:46):
So I think the mathematical sideof me gets really, you know,
intellectually stimulated by that.
There are a lot of parallelsactually between, and that's,
this is the great thing about jazz isthat it's such a mix of different rhythms,
different traditions. And so there's the,
the left brain and theright brain side, right?
I think both of those things appeal tome. Of course, the improvisation aspect.
(49:08):
Improvisation is a veryimportant part of jazz.
So being able to play the sametune night after night after night,
but differently each time is anotherthing that I really enjoy about
jazz. So it's really,
I think it marries the cerebralwith the visceral, you know,
because there's a lot ofintellectual stuff to appreciate
(49:31):
about it, but there's also a lotof rhythm and a lot of groove.
And just having that complicated soup--
jazz is such a soup. It's a rich souptogether. And I think it, that's.
Exactly right. That's why Ilove it. So, last question.
So what would you say is thevalue of the arts in arts
(49:51):
education and producing advancements inSTEM? Science, technology, engineering,
and mathematics.
Yeah. It's really, I think,undervalued. I think I,
I kind of like the acronym STEAM youknow? science, technology, engineering,
arts and mathematics.
There's a colleague down the hallfrom me who has a quote on their door.
It's from, uh, TheoJansen, the Dutch artist.
(50:14):
You may be familiar with the Strandbeest.
Those mechanisms that look likethese big creatures that walk.
And he has a quote. It's something like,
the walls between art and engineeringonly exist in our minds, right?
I agree with that.
That engineering, I mean, youknow this as an engineer yourself,
that engineering at its bestis a very creative pursuit.
(50:36):
Even the pure sciences and mathematicscan be creative pursuits as well.
And so I would say, I mean, Ican speak from my own experience.
My main creative artisticoutlet has been jazz bass.
I think I'm absolutely a more effectiveand creative engineer for being a
musician.
It's certainly made me better at givinglectures because that's a performance,
(50:58):
right? And so a lot of the sameskills from playing jazz bass,
like thinking on your feet and readingthe crowd and reading their response.
That comes in handy whenyou're giving a lecture too.
I'm also a better musicianfor being a scientist and an,
and an engineer because it mademe appreciate the complex theory.
And when I listen toa Charlie Parker solo,
(51:20):
I can appreciate the geniusthat is on display there. Right?
In a very deep and richlysatisfying way that I would not
necessarily have if I didn'tstudy jazz theory. Right.
Understood.
So for me,
I guess maybe the value isin realizing how similar
(51:41):
they are, how they're almost twosides of the same coin, you know,
and they're just two different waysthat I can be myself and be creative
and produce things, right?
So I think I would exhorteverybody listening to this,
particularly those who have a bent towardseither the arts or towards science to
try to explore the other thing too, right?
(52:02):
And to start to see kind ofthe commonalities between them.
Outstanding. Outstanding. Well,we're gonna have to leave it there.
Jeff Moran, thank you forworking towards a cleaner,
healthier future forus and for the planet.
Thank you again forthe invitation. And uh,
(52:23):
it's really a pleasure to be here.
And it's a pleasure to be workingat Mason and I love it here.
So hope to keep doing, hope to keepdoing this for a, a very long time.
Keep doing good stuff.
Alright. I am GeorgeMason University President
Gregory Washington. Thanks for listening.
(52:43):
And tune in next time for moreconversations that show why we are
All Together, Different.
If you like what youheard on this podcast,
go to podcast.gmu.edu formore of Gregory Washington's
conversations with thethought leaders, experts,
and educators who take on the grandchallenges facing our students, graduates,
(53:06):
and higher education.That's podcast.gmu.edu.
Trailblazers in research,innovators in technology,
and those who simply have a good story:
all make up the fabric thatis George Mason University.
We're taking on the grand challengesthat face our students, graduates,
and higher education is ourmission and our passion.
Hosted by Mason PresidentGregory Washington,
this is the Access to Excellence podcast.
(00:27):
Every day at George Mason University,
our faculty are developinginnovative solutions to the world's
grand challenges.
And the great thing about innovationis that sometimes those grand
challenges can have small solutions thatcome from the most unlikely of places.
Joining me today is someone whoknows quite a bit about finding big
(00:50):
solutions in small, unlikely places:
like the bottom of his coffee cup.
Jeffrey Moran is an assistant professorin the Department of Mechanical
Engineering and is an affiliatefaculty member in bioengineering.
His research lies inunderstanding and using microscale
(01:12):
thermofluid transport phenomenato enable new solutions
to fundamental challengesfacing humanity. Jeff,
welcome to the show.
Thank you so much for having me. It'sa pleasure and an honor to be here.
What some of you may not knowis that Professor Moran and I
(01:32):
have a connection, areally, really strong one.
Uh, your postdoc advisor?
That's correct.
His postdoc advisor at MITwas a former student of mine
back at Ohio State, and so we have a very,
very close connection interms of the work that
(01:54):
he's actually doing.
I think we actually met before I cameto Mason at one of the cookouts that he
had.
Oh, that, that could verywell, could very well.
I think were,
I think you were visiting Bostonand he had occasional get togethers,
Professor Cullen Buie is his name.
And he actually just made fullprofessor at MIT, you may have seen.
Yeah, I did. Yeah, I did. And I, Iactually have not congratulated him. Yeah.
(02:16):
So I need to go back and make surehe knows how proud of him I am.
So let's talk a littlebit about your work.
Sure.
So your work is in the field ofmicroscale transport phenomena.
Yeah.
And for those listeners whoare out in the audience,
who could be just inother fields or students,
(02:37):
can you explain a little bitof what that actually is?
Sure. So transport phenomena is a,
a somewhat wonky term thatbasically means the science
of how stuff goes fromone place to another.
And that sounds broad because it is,
the stuff could beliteral stuff like matter.
(02:59):
Think about a drop of food coloringspreading in a glass of water.
And if you don't stir the water,
then the food coloring spreadssmoothly and radially outward
in a process called diffusion.It could be something like that,
but the stuff could alsobe something like heat or
(03:19):
something like electricalcharge, or even fluid motion,
a little vortex or an eddy. Sotransport phenomena, you could argue,
underlie just about everythingthat happens in the universe.
But usually when people use thatterm, they're referring to artificial,
engineered systems.
And I'm really fascinated by thistopic because there are a lot
(03:41):
of parallels in the way that differenttypes of things are transported from
place to place.
I mentioned the example of foodcoloring spreading in a glass of water.
There's also heat, right?So you could imagine, like,
your stove top in the morning afteryou make coffee in the morning,
you turn the heat on and the temperatureis hot right in the center of the
(04:02):
burner. And then it spreads radiallyoutward after you turn the heat off.
And it turns out the math that describesthat process is essentially identical
to the math describing thefood coloring: diffusing.
And so it's fascinating froma fundamental perspective,
but it's got lots of applications,
especially in things like the chemicalindustry or in, uh, microfluidics:
(04:24):
the science of fluid flowthrough small passageway.
And the microscale is just referringto the fact that I like studying these
phenomena at the microscopic level.
And my fascination really derivesfrom the fact that we can see
some really bizarre consequencesof those transport phenomena
(04:45):
that you would never seeat the macroscopic scale. And we'll get into this,
but these include things like a tiny pieceof platinum connected to a tiny piece
of gold actually propellingitself at the microscale in
hydrogen peroxide. Something you wouldnever see at the macroscopic level.
So that's a bit of a flavor ofwhat transport phenomena refers to.
(05:06):
Well, that's interesting. So whatdo these phenomena look like?
Yeah. So some of them are visibleto the naked eye, like I was saying,
with the dye spreading in water.
Some of them are invisible or they'reonly visible under a microscope.
Something like moleculesmoving from place to place.
Some of them are completelyinvisible. Like for example,
(05:28):
my PhD work was studying theseself-propelled particles, right? We're,
and we'll talk a lot aboutthese, but these are tiny rods,
small enough that you need amicroscope to be able to see them.
And what's fascinating about them isthat they actually propel themselves by
pushing an electricalcurrent through the solution.
(05:50):
So ions are generated on thefront end and consumed on the
back end. And as a consequence of that,
ion motion propulsion is generated.So that's invisible, right?
Because if you were to justlook at it under a microscope,
you would just see the rods zippingaround in the fluid in the presence of
(06:10):
hydrogen peroxide.
So some of them are visible like thedye spreading in the glass of water.
Some of them are invisible,
like the charges moving their waythrough the solution and ultimately
causing a variety of different forcesto be generated that lead to propulsion.
So it really depends on the typeof transport you're talking about.
So as a young person who'sgotten into this field and
(06:35):
developing a passion forit, how did that develop?
What connected you to start looking at the
micro and nano scale?
Yeah. So I got into researchlate in my undergraduate days.
I was participating in a programwhere undergraduates could
(06:55):
be paid to do researchin a professor's lab.
We have an analogous program at Masoncalled the Undergraduate Research Scholars
Program, through which I've mentoredabout nine undergraduate students.
And part of the reason for that is that I,
it was such a valuable experience for me,
and I just had the chance to workfor a professor whose lab focused on
(07:15):
microfluidics.
As far as how I got intothe self-propelled particles
specifically, that was by accident.
It happened when I went to a master'sthesis defense early in my graduate school
days.
And there was a student who wasdefending his master's thesis.
And the thesis topic was howto manufacture the platinum gold rods I was talking
(07:37):
about.
And the focus of his work was on moreefficient ways to manufacture them.
But he just happened to mention offhandthat they happened to propel themselves
in water, if you addhydrogen peroxide as a fuel,
and that intrigued me. So Iraised my hand and I said,
(07:57):
how did they do that exactly? And it
wasn't really his main focus,but he, his explanation,
so he can be forgiven for givinga somewhat arm wavy explanation,
but he basically said, well,we don't really know, but it's,
it has something to do with the flowbeing induced in the fluid near the rod's
surface. And you know, the flow goesbackward and the rod goes forward.
(08:21):
And I sat back and I thought, Hmm.
So I had the fortune of having athree year fellowship that allowed me
the freedom to pursue whateverI wanted for my thesis work.
So I approached my advisor and told himI was interested in really getting to
the bottom of this. And thateventually became my thesis.
(08:45):
And you know, this is a very youngfield. It just started in 2004,
and so it's just passing the 20 year mark.
And I've just never been able toshake off this fascination with
how we can make these seeminglyinanimate objects that are not
living in any way moveand do things that mimic
(09:08):
biological systems at themicroscale. And as an engineer,
I'm especially interested inwhat practical applications these sorts of devices
could have.
So my fascination with this reallyarose from that chance encounter at that
thesis defense. But people have beenthinking about this for a while. You know,
there are classic films like FantasticVoyage from the 1960s where a team of
(09:30):
scientists shrink their submarine downsmall enough to enter the bloodstream of
a colleague and treat ablood clot in his brain.
So people have been thinking about thisand what applications it could have,
ways it could revolutionizemedicine for, for quite a while.
And at Mason,
I'm really trying to marry thatfascination that I still have from my
(09:51):
graduate school days with a sort ofutilitarian outlook and thinking about
ways that we can start to realize thevision articulated in things like the
Fantastic Voyage film.
So that's a little bit about how myfascination came about. You know,
when I worked for Professor Buie atMIT, we were doing different things.
We were working on some differentareas. And when I came to Mason,
(10:14):
the time came to establishmy own research program.
And so I'm incorporating someof what I did in my postdoc,
but my focus is really on using theseself-propelled particles to benefit
various different societal applications.
Well, let's talk about that.
Because that is what is soincredibly fascinating. Mm-Hmm.
So earlier this year,
(10:34):
members of your lab made the news withthe invention of what's being called
the CoffeeBot.
And this is spent coffeegrounds coated in iron oxide
that can absorb pollutants and water.
That's right.
So tell me about how it works.
Sure.
How do they move throughthe water? And then let's,
(10:54):
let's get into it a little bit.
Yeah. So on that topic, I actuallybrought some visual aids here.
So the, the listeners can't see this,
but I'm holding a vial of what arejust ordinary coffee grounds, right?
And these are coffee grounds Iliterally brought from home and.
Now spent coffee grounds, which means.
(11:15):
Spent coffee grounds.
Which means they've been used.
That's correct.
That's even better.
That's correct. Yeah. And by one estimate,
we throw away about 23 milliontons of spent coffee waste per
year. Much of that isbeing sent to landfills.
Although increasingly I'm heartenedto see that places like Starbucks
are making just bags of the stuffavailable for folks to use for compost.
(11:38):
So I've got a vial ofspent coffee grounds here,
and in my other hand I have a magnet.Now, if I hold the magnet up to the vial,
nothing interesting happens.Coffee is not magnetic. However,
if I have another vial here, thesealso look like spent coffee grounds.
They are. But they've been coatedin, as you said, iron oxide,
which is the main chemicalconstituent of rust.
(12:00):
So we sometimes call these rustycoffee grounds because in a real sense,
they are rusty. And if I hold the magnetup, I don't know if you can see, uh,
and for the listeners, the coffee grounds,
once they've been coated inthe iron oxide particles,
they will actually follow the magnet.
So I can make them go wherever Iwant to by holding up a magnet to it.
(12:25):
So the essence of what wedid was develop a safe and
eco-friendly approach to coating thecoffee grounds with these little tiny
bits of rust. So what does that do forus? Well, it does two important things.
First, it allows us to use a magneticfields. You asked how they move.
It allows us to use a magnetic fieldto drive them through the water.
(12:48):
So for now, we're just propellingthem with the external magnetic field.
We can come back to that in a second.
We're looking at waysto improve upon that.
And one of the things we demonstratedwas that moving coffee grounds will
actually remove pollutants from watermore efficiently than stationary ones do.
And this makes intuitivesense because, in a sense,
(13:09):
the moving coffee grounds encountermore pollutants per unit time than
stationary ones do. So we demonstratedthree different pollutant types.
Methylene blue, which is kind of astand-in for a chemical pollutant.
But methylene blue itself isa textile dye that has some
negative health effects,
that is itself a pollutant ofconcern in some areas of the world,
(13:31):
particularly where textileproduction is common.
Oil spills and microplastics:
those are additionallypollutants of concern.
So both of those are problematic.
Absolutely.
Today. Oil spills and microplastics.
So much so fish todayHave an incredibly large
amount of digested microplastics intheir, in their, in their systems.
(13:56):
And potentially we do too, potentially.
And because there are so many consumerproducts that contain plastic,
they make their ways into waterways,right? And eventually in some areas,
uh, it probably varies significantly.I haven't seen the statistics,
but definitely lots of differentforms of life are consuming these
microplastics. And I wanna say, this isnot my area, but I think we're still,
(14:18):
as a community, figuring outexactly what the health effects are.
But they're definitely somethingto be concerned about for sure.
So we demonstrated that we canremove each of those three types. Um.
So microplastics...
Mm-Hmm.
is a textile dye. And it'sblue as the name suggests.
(14:41):
And that was convenient because thenit's very straightforward to monitor
how much of the methylene bluewe've removed at any given time.
Because you can use an instrument thatessentially looks at how much blue light
is being absorbed.
You can use essentially the intensityat a certain wavelength to determine how
much of the dye is left. So it was,
(15:03):
it was partially out ofconvenience that we chose that.
Hmm. So
reuse of these coffeegrounds was mentioned.
Yeah. Yeah.
So how often can you use them?
Yeah. So that brings me to the secondmajor thing. That the magnetism enables.
So just to recap,
the first thing the magnetism does isit allows us to drive them through the
(15:25):
water. And that speeds up thepollutant removal process.
The second thing it does is it allows usto take the magnet and pluck the coffee
grounds out of the water afterthe treatment is complete.
What we do next is rinse it off.We can rinse the pollutants off,
and we do still have to disposeof the pollutants elsewhere.
That is a separate issue that is for now,
(15:46):
tangential to the work that we're doing.
We're mainly focusing onremoving them from the water.
But that is something that you do stillhave to do something with the oil or
with the microplastics.
And that's something that otherresearchers are working on.
So then after you rinse them,
we typically rinse them with anorganic solvent like acetone.
Acetone works pretty well.
(16:07):
And then you can actuallydrop them back into the water.
And we showed in the journal paperwe published on this that you can
reuse them at least four times with aminimal reduction in pollutant removal
efficiency. So wehaven't gone beyond that.
But based on how well the first fivetrials went, and this is true by the way,
(16:28):
with each pollutant class, withdyes, oils, and microplastics,
we have reason to believethat you could go further.
So let me get this straight 'cause Iwant to make sure that the folk out there
see the depth and theprofoundness of what you
are stating.Spent
coffee grounds coatedand iron oxide can be
(16:53):
dropped into, say, an oil spill.
Absolutely.
And the coffee grounds willattach themselves to the oil.
That's right.
You have a process forthen pulling those grounds,
separating those grounds withthe oil on them from the water.
The oil is rinsed offwhere it can be disposed.
You throw the grounds backout to repeat the process.
(17:15):
And you can do it up to four times.
Five times total. Right. So four reuses.
Four reuses.
So five times total. So five total uses.
That's amazing.
You nailed it. That's exactly right.
And so when you talk about the coffeegrounds attaching themselves to a
pollutant like oil, or microplastic,how long does that take?
Is it an immediate attachment or...
(17:36):
So that's a good question.
And it's one that we are really workingon answering more systematically,
to really be able tosay, if you have, say,
a section of a river thathas a certain area, say,
an acre,
and you have a rough estimateof how much oil has spilled,
(17:58):
there's been an oil spilland some X number of liters.
We don't really currently havea number to say definitively,
this is how much coffee you wouldneed for that section of the river.
But much of the testing we've done sofar has been mainly on the size scale of,
you know, a small beaker, asmall container. That's maybe,
maybe a quarter of a liter of water.
(18:20):
And we can get away withabout 50 milligrams of coffee.
So just enough to sprinklethe coffee bots in a,
a layer that will approximatelysparsely coat that top layer.
And then as you say, the pollutantsattach themselves to the coffee grounds.
Does that happen immediately?
It's not immediate. So itdepends actually on how,
(18:42):
whether the coffee groundsare moving, first of all.
So if they're stationary by themselves,
the testing we did was on thetimescale of about 40 minutes.
And after 40 minutes withstationary coffee grounds,
some of the pollutanthas been removed. Right?
But if you drive them through thewater, it increases from about 50,
(19:02):
60% to about 90 to 95% inthe case of methylene blue.
In the case of oilspills and microplastics,
it's on a similar order.
Wow. That's amazing. So...go ahead.
Oh, I was just gonna say, becauseanother question that I've gotten a lot,
and that is a good question,
is what is it that attaches thepollutants to the coffee grounds?
(19:24):
Right. That's a fair question.And in the case of oil spills,
it has to do with a propertycalled hydrophobicity.
And it means basically, as thename suggests, hydrophobic,
it turns out that the coffee groundsare what we call hydrophobic.
So for folks listening out there, ifyou've ever waxed your car, right?
(19:47):
And you put some droplets of wateron afterward, it kind of beads up.
Because the wax has renderedthe surface hydrophobic. It
doesn't like water. So whenwater comes in contact with it,
it tries to avoid touching thesurface as much as possible.
So that's why it forms that bead.
And we have some pictures from the paperwhere if you take a bed of spent coffee
(20:11):
grounds, it does the samething. So why does that matter?
It matters because thingsthat don't like water
tend to like oil.
So the same interactions that causeoil droplets to coalesce together
in say, salad dressing arealso the forces we believe,
and we have good reason to believe,
(20:31):
that cause oil to glomonto the coffee bots.
And there's some nice videosthat are included with the paper,
and also in the news segment that wasfeatured on Channel 9 news in March of
this process actually happening.
So it looks kind of like the coffeegrounds are kind of soaking up the oil.
Huh. Amazing.
Yeah. And a similar thing we thinkis happening with microplastics,
(20:54):
because microplastics arealso hydrophobic in general.
So it's a good rule of thumb thathydrophobic things tend to like to
congregate with other hydrophobic things.
Okay. So you know, this is amazing. So
the question that I always havewhen confronted with, you know,
(21:15):
this is an everyday product.
Sure.
You know, we toss thecoffee grounds all the time.
That's right.
How did you discover such a use outof something that most of us consider
trash?
Yeah. This is where I have togive credit to my group members.
So I had two awesome members ofmy group who have since gone on to
(21:38):
other things.
It was a postdoc in my groupnamed Amit Kumar Singh.
And at the time, a high schoolsenior named Tarini Basireddy.
Amit is now a professor himselfat a university back in India.
And Tarini is just beginning hersophomore year at Johns Hopkins.
We were trying to figure out aproject for Tarini to work on,
(22:00):
because she was doing a year longinternship in my lab as part of a,
she was a senior at ThomasJefferson High School.
And they had this program where, um,their seniors can do research internships,
and Mason, quite understandably,
has restrictions on things thatminors can do in the lab. Uh,
so what happened was, you know,
we were thinking about aproject that would involve
(22:25):
the things that I was interested in onusing particles that move in liquids that
would not involve any particularhazards. And it was one of those, Hey,
what if we tried this kind ofconversations that I've come to love,
I've come to treasure those conversationsbecause they can lead to interesting
things like this. And I should say,
(22:46):
we are not the first people touse self-propelled or magnetically
propelled nanoparticles ormicroparticles to clean up water.
There have been a variety of differentstudies in that direction already.
The problem is a lot of those arejust proof of concept demonstrations,
that if you have a particle that's madeof maybe a metal or some other toxic
(23:07):
substance, but if it moves and it'sable to break down pollutants, you know,
people will publish thatand they'll say, look,
we can use propelledparticles to clean up water.
But one of the major focus areasof my lab in general is trying to
engineer these kinds ofparticles from safe materials.
And we were brainstormingone day and one of us said,
(23:31):
I'm not sure that it was me. I don'tthink it was me. One of us said,
what about coffee as a way todemonstrate water treatment with
active particles?
Yeah. But why would they say coffee?You know what I'm saying? It makes,
absolutely, that's not whatyou would think of when...
Yeah. Well I have, uh...
I mean, I would think of sandbefore I would think of coffee.
(23:52):
Yeah, absolutely.
You know what I'm saying?
Well, sand is another material that wework with or silicon dioxide. And we'll,
we will get to that in a separateproject. But, you know, my postdoc,
particularly Amit, I used to say,you give him any three materials,
he would figure out a way to make, makea self-propelled particle out of it.
And so he had a previouspaper on using tea buds,
(24:16):
like bits of tea,
to make nanoparticleantibiofilm treatments.
So things to treat bacterialbiofilms, for example,
which are part of how antibioticresistance comes about.
So it was just one of thoserandom sort of suggestions
that once somebody said it,
we all kind of sat back for aminute and thought about it.
(24:38):
And it started to make more sense. Becausefirst of all, as we've already said,
coffee is discarded by the millionsof tons every year. It is hydrophobic.
So it, it can pick upother hydrophobic things.
And if you look at a microscopeimage of a coffee ground,
it has this very irregular,
very dense surface where whatI mean is that there's a lot of
(25:00):
active surface area given thesize of the coffee ground,
which means it can pick up alarge quantity of pollutants relative to its size.
So the answer to the question "whycoffee?" is really three-pronged:
it's hydrophobicity, it's common andit's relatively safe to work with,
and it has a high surface area to volumeratio, which turns out to be important.
(25:25):
Hmm. That is amazing.
So what do you think a discoverylike this could have on
protecting and preservingwater systems around the globe?
Yeah, I mean,
we certainly hope that it has farreaching impacts in all corners of the
world. There are lots of areas wheretwo things are true at the same time.
(25:46):
One, there's an urgent lackof clean available water.
Two coffee is produced and orconsumed in large quantities.
An example would be Ethiopia. Ethiopiais facing a water crisis right now,
and they also grow andconsume more coffee,
to my knowledge than anyother country in Africa.
(26:08):
But there are other countriesas well. Brazil, Vietnam, Peru,
other areas of the world where coffeehas grown and produced and consumed.
But people don't always have accessto clean water. And in many cases,
actually the challenge is notnecessarily lack of water per se.
(26:28):
It's lack of access tomethods to decontaminate the
water that is already therein ways that don't use,
or that don't require extensiveinfrastructure that is not available to
everybody in the world.
So our hope is that wecan eventually disseminate
this method and enable peoplewho don't have, you know,
(26:51):
a huge amount of scientific training,
don't necessarily have accessto nano fabrication equipment,
which I have to say a lot ofpeople in my field still rely on to
basically use the materials theyhave available to them and to
make these themselves. And, you know,it could be implemented in the home,
(27:13):
for example, you couldimplement it in just a cup of,
of of water that youwant to decontaminate.
You could envision this beingimplemented on a small boat where there's
a magnet on the back end of the boat.
And so if you wanna clean upan oil spill in a small river,
you can deploy it that way, deploy alarge quantity of these coffee bots,
(27:33):
and then move the boat along.
And it kind of tugs the bed of coffeebots behind it--in the news segment they
made a nice animation ofwhat this would look like.
Or you can imagine somethinglike sewage treatment ponds.
So in water treatment plants,
they often will just leavesewage to sit and allow the,
all the microbes to break itdown and decompose it over time.
(27:55):
So you can imagine just,
and you don't even necessarilyneed them to be magnetic,
you just need to put a whole bunchof coffee grounds on the top layer.
And over time it willbreak down the pollute,
or at least we believe itwill absorb, I should say,
absorb the pollutants more efficientlythan just if you left it to decompose
over time.
Huh. Interesting.
Yeah. So there are alot of potential uses.
(28:16):
So we're in the process of, we'veapplied for a patent on this and...
Yeah, you should.
We, we published this work in a scientificjournal a few months ago. Tarini,
now a sophomore in college, is ajoint first author on the paper.
Wow.
And I think when I was her age, I didn'treally even know what research was.
Well, let me make sure,lemme make sure we're clear.
(28:37):
Yeah.
Most high school seniorsdon't get a publication.
Oh yeah.
A first author publication at that. Okay.No, that is, that's really cool. Now,
your previous advisor at
MIT when he was my student. That's wherehe came to me after his freshman year,
he started working with me in my lab.
(28:57):
I remember that.
Yeah. So, so this is, you're,you're keeping that tradition going.
And that is phenomenal.
Getting started early.
That's exactly right. Yousee where it can turn.
And I hope that you stay in contactwith this young person and that you
help guide her along togoing to grad school.
She has a bright futureahead of her, for sure.
(29:18):
Outstanding. Yeah. So I'mgonna shift gears a little bit.
In August it was announced that youand your colleague at Purdue University
received NSF funding to design astudy for astronauts to conduct on the
International Space Station.
The research aims to betterunderstand thermophoresis, or
(29:39):
the migration of particles inresponse to temperature gradients.
And that can happen with orwithout the influence of gravity.
So as your work mainly focuses withparticles moving through water,
how do you realize that there wasthis a gap in knowledge about how
aerosols might actually migrate inresponse to temperature and that how they
(30:00):
might migrate without gravity.
Mm-Hmm.
this is another example of aproject that originated from just a
very casual, "what if wetried this?" conversation.
So the impetus for this is that theNational Science Foundation has a program
called Transport PhenomenaResearch on the ISS to benefit
(30:24):
life on Earth. So we invoketransport phenomena again.
And I was telling,
and I I should mention that I've beenobsessed with space since I was a little
kid.
The house I grew up in is still litteredwith drawings of space shuttles and
models of fighter jets andthings like that. It, it was, uh,
one of the major draws for me to getinto engineering in the first place.
(30:45):
I understand that one.
And so I've actually wanted tobe an astronaut for a long time.
I applied to the astronaut call in2016. Didn't get selected, obviously,
but there's still a part of methat really wants to go to space.
And so I was really interested in thiscall because if I can't go to space
myself, getting to send an experimentup there is kind of the next best thing.
(31:09):
That's exactly right.
So I was talking to my friend andcollaborator, David Warsinger.
We're kind of going through thejunior faculty process together.
We met at MIT when he was a gradstudent, and I was a postdoc.
And I told him about this and hejust offhandedly said something like,
has anyone made a microswimmer that moves in air?
And micro swimmer isanother term for my field.
(31:33):
There are lots of different terms,self-propelled particles, micro motors,
active colloids, things like that.
And initially the questionstruck me as rather odd.
It was not something Itypically think about.
My field is overwhelmingly concernedwith propulsion through liquids
and gels, not air.
But air is a, can be considereda fluid in some sense.
(31:55):
Absolutely. Yeah. So, right.And so it got me thinking,
and I kind of sat back and it was avery similar moment to the moment when,
back in 2008 at the master's defense Imentioned when the guy mentioned that
these particles happen toswim. It's just kind of,
I kind of sat back and thought, huh,that's odd. How might that work?
(32:18):
And so then I got to thinking aboutthe mechanisms that are active in both
liquids and gases. And oneof those is thermophoresis.
So thermophoresis essentially means it's a
phenomenon, it's a transport phenomenonthat happens in liquids and gases.
And it's basically whensmall particles under certain
(32:40):
circumstances, if they arein temperature gradients,
which essentially means thatthe fluid on one side is cold,
the other side is hot,
there is a force that is aresult of transport phenomena.
There is a force that can push theparticle either in the direction of hot
or in the direction of cold.
Oh. So the force works both ways?
(33:02):
It depends.
So it's not always hot. Usuallyit's cold to hot, right?
In liquids, it can be in either direction.
I see.
It depends on the liquid and itdepends on what you add to the liquid.
And I should mention in liquids,
it's not really fully understood exactlywhat causes it to move towards hot or
towards cold. In gases, however,it's more straightforward. In gases,
(33:22):
motion by thermophoresis prettymuch always occurs from hot to cold.
So if you have a particle that's in air,
and the air is hot on oneside and cold on the other,
then the nitrogen and oxygenmolecules on the hot side
are by definition zipping aroundwith more velocity, right?
When they collide with the surface ofthe particle, they impart a force to it.
(33:45):
On the cold side, they'rezipping around with less energy.
So the force that they impartfrom the cold face is less.
And so the end result is thatthere's a net force owing to the more
forceful collisions on the hot sidethat pushes the particle towards cold.
So this is known to happen in gases,but then I got to thinking, okay,
(34:07):
could we then quantify it somehow?
And it's difficult to do on earthbecause of things like gravity,
which will cause the particlesto fall out of the air.
And there's an additional problem withthermophoresis because hot air rises,
right? So if you were to try tohave a sample of particles and air,
and you somehow kept them from fallingto the ground and you heated the air on
(34:31):
one side, it would rise. And thatwould cause the particles to move.
And it would be hard to discern how muchof the particle motion is really due to
thermophoresis in that case.
I see. I see.
So what we realized wasthat in microgravity on the international Space Station,
you don't have thoseconfounding factors, right?
And it would be possible, we think,
(34:54):
to isolate just the componentof thermophoresis that
drives different typesof particles through air.
So why would anybodycare about this? Right.
That was kind of the next question thatwe had while we were thinking about
this. And it turns out that aerosols,
small particles suspended in air,
(35:16):
are very important to ourunderstanding of the global climate.
And they pose a pretty largeamount of uncertainty actually,
in terms of what their neteffect is on the global climate.
Some aerosols actually can exert an
overall cooling effect. Someaerosols warm the planet.
(35:38):
Aerosols are produced byvolcanic eruptions, dust storms,
other natural events like that.
Human activity like burning fossil fuelsalso injects a bunch of aerosol into
the atmosphere.
And so it's a very active area ofresearch in climate science right now.
And so what we're intending todo is take measurements of how
(35:58):
efficiently different aerosolsmove by thermophoresis.
And the hope is to help climatescientists understand how important this
mechanism is in the atmosphere,
because the problem of aerosols inthe atmosphere is only gonna increase.
Rocket launches are anothermajor source of, uh,
space junk that can sometimesbe in the aerosol range. Um,
(36:20):
and it turns out that thisphenomenon, thermophoresis,
is most important at very high altitudes.
Hmm. Interesting.
So that's one part of the project.And the, the swimming part,
the self propulsion partis to look at whether,
instead of say applying heat on oneside and cold on the other side,
looking at just a single particle withhalf of its surface coated in a metal,
(36:43):
something that absorbs light reallyefficiently shining a light on it,
and then seeing if the metal sideabsorbs the light more efficiently
than thus heating up faster, that willthen heat the air surrounding the,
the metal side leading to propulsion.
This is something that's been demonstratedon earth but has never been seen in
air before.
So we call this self-thermophoresisbecause here the particle doesn't require an
(37:08):
external temperature gradient, but itgenerates it itself and then moves.
So we're gonna also see whether thathappens and we call those micro flyers
instead of micro swimmers.
so there's a healthcare, uh,spin on this as well, right?
I mean aren't the vectors for carryingdisease, especially Covid, for example,
(37:31):
as carried like an aerosol.
Yep, absolutely.
And so, so you have,
if you can deliver somethingharmful using this mechanism,
you can actually deliversomething helpful.
That's right. That's right.
So I think NASA wouldprobably balk at the idea of
(37:53):
us sending virus-ladenaerosols to the space station.
They might have one ortwo issues with that.
But it's a very good point.
And that is an additional applicationwe're interested in because if we
find that thermophoresis indeedis an efficient way to move
aerosols around,
this could suggest anothermethod to collect virus laden
(38:18):
aerosols from say, the HVACsystems of hospitals, right?
Which is obviously a big problem there.
And we're still figuring out exactlywhich aerosol materials we're going to
send. So we launch sometimelikely in the second half of 2025.
And most of the materials we'reinterested in are things like,
(38:40):
I mentioned sand earlier,sulfate aerosols.
These are aerosols that comefrom volcanic eruptions.
They're also geoengineering proposalsto intentionally inject aerosol to cool
the planet. Obviously controversial.Lots of research going on into them.
So we're looking at that (38:56):
sodium chloride, believe it or not, table salt.
Comes from sea spray.
And that can actually drift todifferent parts of the globe.
And that can affect the climate inways that we don't fully understand.
But we're also looking at somethingthat could act as a stand-in for
an aerosol that is produced by say,somebody coughing or somebody sneezing,
(39:18):
and we'll see what we see.But you could easily envision,
and this has somewhat been exploredbefore, but you could envision, say,
having a stream of air where you havethe stream going in one direction,
and then a temperaturegradient perpendicular to the stream of air so that the
particles, the aerosols, ifthey migrate thermophoretically,
(39:39):
they would bend toward the cold side.And just be collected on the cold plate.
So the viability of that, you know,
that is something you could in principletest on the ground, you could test.
On the ground and youcan test that at scale.
Yeah, that's right. So what's gonnahappen is on the space station,
there's actually a microscopeon the space station already.
And so what we're doing isdesigning and building a,
(40:01):
an apparatus to apply thetemperature difference to a series
of different cuvettes--tiny transparentcontainers--that each of which
contains a different particle sample.
And so the ISS crew isgoing to then look at those
different samples, apply thehot and the cold as needed.
(40:22):
We're gonna be able to watch inreal-time as the astronauts perform the
experiments and measurethe migration speeds
of these different aerosolparticles as a function of say,
what type of particle they are, youknow, the temperature difference,
things like that.
As we start to wrap uphere. So what drives you to,
(40:42):
towards this sort of innovative research?
I could sum it up in oneword, which is curiosity.
Hmm. Interesting.
I have in this job as a,
one of my favorite parts of thisjob is that I have the privilege
to
pursue ideas that pique my interestwithout much more of an imperative than
(41:05):
that. Actually, Professor Buie, my mentor,
your protege, he once described itas being an idea entrepreneur. And,
you know, it sounds like him, right?He's, he, he's, he's got a way with words,
with he is a way of coiningthose kinds of phrases.
But I think it captures a lot of whatI love about this job, along with,
of course, working with andteaching and mentoring students.
(41:27):
That's definitely another favoriteportion. But like I said, you know,
both coffee bots and this ISSproject both grew out of just
conversations I was having.That piqued my curiosity.
And because I have this role,
I was able to follow up on that curiosity.And in the case of the ISS project,
(41:48):
write a grant proposal about it thatjust so happened to be funded. And
so I really think curiosity-drivenresearch is a buzzword you hear sometimes.
And I think it's certainly good for doingresearch that is just kind of on the
pure science side that is just, you know,to kind of satisfy our, our curiosity.
But I think it's also a good wayto unexpectedly discover new roots
(42:13):
for applied research, likein the example of coffee.
So I'm a big fan of curiosity.
I think I've been able to work ona really eclectic mix of different
problems as a faculty member frommaking more insulating wetsuits
to the projects that we've beentalking about today to other
(42:33):
projects and collaborations I havethat are more on the medical side where
we're trying to, say, penetrate abacterial biofilm with active particles.
A lot of these really, the impetus forme, really stems from my curiosity.
That's what got me into thisself-propelled particles field in the first place.
Just that I wasn't really satisfied withthe answer that I got in that master's
(42:55):
thesis defense. And, you know,
I was able to just follow upon it and make it my thesis.
So if there's one driving force, it,it would definitely be that just,
I'm just a curious person by nature,
and I have a hard time shaking offquestions that really get under my
skin and that I reallywanna know more about.
No, that's cool. Well, Jeff, there'splenty of room at the bottom.
(43:17):
So I often invoke that speech
Plenty of room at the bottom.
There is, uh, the, the speechby Richard Feinman in 1959.
Fineman. That's exactly right.
And in that speech, he talks aboutswallowing the surgeon. He said,
there's a friend of his that said it, it,
it would be very interesting in medicineif you could swallow the surgeon that
(43:41):
it goes inside the body and, you know,goes to an organ and looks around.
And actually later in that speech,
he challenged the community to builda tiny motor that fits inside a cube,
1/64th of an inch on its side.And a lot of what we're doing is,
is exactly that, is we'rereally trying. In fact,
we could probably fit muchsmaller than 1/64th of an inch.
(44:02):
Some of the particles we work on aretoo small to even be seen on an optical
microscope. So, well, yeah.There's plenty more to do. Yeah.
That is really cool. Yeah. Um,that's cool for drug delivery.
That's cool. For all typesof treatments for disease.
So really, really cool stuff.
And I should mention, you know, this hasreally grown in the last 20 years to a,
(44:25):
a robust field in its own right.
The first ever startup company thatI'm aware of was founded recently by
a guy in Spain named Samuel Sanchez,
who's kind of one of thesuperstars of the field.
They're looking to develop a bettertreatment for bladder cancer.
Part of it has to do with makingparticles that use enzymes,
nature's catalysts, asthe engines, basically.
(44:48):
And we have some other projects in thelab that use those very same enzymes
partly for, for biofilm eradication orother sorts of applications like that.
So it is growing, and I don'tknow if we're gonna see it,
we're not gonna see it in clinicsin a year or in five years,
or probably not even in 10 years,but maybe in 15 years, right?
There are some fundamental challengesthat we still have to address.
(45:12):
And on the medical side, we haven'treally talked about that today,
but on the medical side, we're reallytrying to address, uh, some of those,
particularly making themfrom safe materials.
That is cool. As a wrap up here,
one of the things that I really,
really like about you isthat your passion is not just
(45:32):
in engineering. It's not just in thesciences. You know, I was happy to see,
uh, one day when we had our jazzmusician quartet at the house
playing music for one of ourevents to say, wait a minute,
that guy looks familiar.
And so you, and so you moonlightas a freelance jazz musician.
(45:53):
Specializing in the double bass.
That is correct.
So talk a little bit about that,
how long you've been playing the doublebass and what excites you about jazz.
Yeah. Well, I've been playing thebass since I was in sixth grade. So,
quite a while, quite a while.
But I've been entranced by the doublebase for as long as I can remember
(46:14):
since I was about four,
I think I was about four when I startedbegging my parents to get me an upright
bass.
And my mom still has someembarrassing photos of me as like
a 4-year-old wearing atuxedo for Halloween.
I was a conductor tryingto conduct the orchestra,
and I can't really saywhat drew me to the bass.
(46:35):
I still can't really fully explainit. And maybe that's part of a,
a testament to how powerful itis. I just love the way it sounds.
I love the depth,
I love the character of awell-struck double bass string,
a well-plucked double bassstring, you could say.
And so I did piano lessonsas a kid, like many kids do.
(46:55):
Didn't really enjoy themthat much, but it really, it,
it was useful though because I learnedhow to read music that way. And,
you know, also having a prettyrobust interest in math. I,
I saw pretty quickly the parallelsbetween music theory and mathematics.
Okay. So that was gonna beone of my next questions.
(47:16):
Yeah. Yeah. So
I had the chance to take amusic appreciation elective,
and there was one day where they justturned us loose to try out different
instruments and I made a beeline forthe double bass and just haven't really
set it down since. Incollege, in undergrad,
I was briefly for about two years,
(47:38):
a double major in jazz performanceand mechanical engineering.
I ended up just sticking with theengineering major. But during that time,
I had the chance to study with ajazz bass instructor who really
was a fantastic mentor to me, notjust as a musician, but just as a,
as a young adult.
So I think I got what I needed becauseI realized that you don't need a music
(48:01):
degree to play music.
But the same is not exactly true fordoing engineering work professionally.
So college was when I reallystarted to freelance on the bass.
And it ever since has been acreative outlet and it's been
something I've been able tocontinue to do, which I'm really,
really happy about. Um, so, so youasked about jazz. You know, we,
(48:25):
we had jazz records playing in thehouse growing up. I was in, you know,
classical orchestra in high school.
And I still enjoy classical music as well.
But I think part ofwhat drew me to jazz was
it can be very mathematical, it can bevery complex in terms of the harmonies.
(48:46):
So I think the mathematical sideof me gets really, you know,
intellectually stimulated by that.
There are a lot of parallelsactually between, and that's,
this is the great thing about jazz isthat it's such a mix of different rhythms,
different traditions. And so there's the,
the left brain and theright brain side, right?
I think both of those things appeal tome. Of course, the improvisation aspect.
(49:08):
Improvisation is a veryimportant part of jazz.
So being able to play the sametune night after night after night,
but differently each time is anotherthing that I really enjoy about
jazz. So it's really,
I think it marries the cerebralwith the visceral, you know,
because there's a lot ofintellectual stuff to appreciate
(49:31):
about it, but there's also a lotof rhythm and a lot of groove.
And just having that complicated soup--
jazz is such a soup. It's a rich souptogether. And I think it, that's.
Exactly right. That's why Ilove it. So, last question.
So what would you say is thevalue of the arts in arts
(49:51):
education and producing advancements inSTEM? Science, technology, engineering,
and mathematics.
Yeah. It's really, I think,undervalued. I think I,
I kind of like the acronym STEAM youknow? science, technology, engineering,
arts and mathematics.
There's a colleague down the hallfrom me who has a quote on their door.
It's from, uh, TheoJansen, the Dutch artist.
(50:14):
You may be familiar with the Strandbeest.
Those mechanisms that look likethese big creatures that walk.
And he has a quote. It's something like,
the walls between art and engineeringonly exist in our minds, right?
I agree with that.
That engineering, I mean, youknow this as an engineer yourself,
that engineering at its bestis a very creative pursuit.
(50:36):
Even the pure sciences and mathematicscan be creative pursuits as well.
And so I would say, I mean, Ican speak from my own experience.
My main creative artisticoutlet has been jazz bass.
I think I'm absolutely a more effectiveand creative engineer for being a
musician.
It's certainly made me better at givinglectures because that's a performance,
(50:58):
right? And so a lot of the sameskills from playing jazz bass,
like thinking on your feet and readingthe crowd and reading their response.
That comes in handy whenyou're giving a lecture too.
I'm also a better musicianfor being a scientist and an,
and an engineer because it mademe appreciate the complex theory.
And when I listen toa Charlie Parker solo,
(51:20):
I can appreciate the geniusthat is on display there. Right?
In a very deep and richlysatisfying way that I would not
necessarily have if I didn'tstudy jazz theory. Right.
Understood.
So for me,
I guess maybe the value isin realizing how similar
(51:41):
they are, how they're almost twosides of the same coin, you know,
and they're just two different waysthat I can be myself and be creative
and produce things, right?
So I think I would exhorteverybody listening to this,
particularly those who have a bent towardseither the arts or towards science to
try to explore the other thing too, right?
(52:02):
And to start to see kind ofthe commonalities between them.
Outstanding. Outstanding. Well,we're gonna have to leave it there.
Jeff Moran, thank you forworking towards a cleaner,
healthier future forus and for the planet.
Thank you again forthe invitation. And uh,
(52:23):
it's really a pleasure to be here.
And it's a pleasure to be workingat Mason and I love it here.
So hope to keep doing, hope to keepdoing this for a, a very long time.
Keep doing good stuff.
Alright. I am GeorgeMason University President
Gregory Washington. Thanks for listening.
(52:43):
And tune in next time for moreconversations that show why we are
All Together, Different.
If you like what youheard on this podcast,
go to podcast.gmu.edu formore of Gregory Washington's
conversations with thethought leaders, experts,
and educators who take on the grandchallenges facing our students, graduates,
(53:06):
and higher education.That's podcast.gmu.edu.
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