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to Wednesday Nite at the Lab. >> I'm Tom Zinnen.ody,
I work here at UW-Madison for UW-Extension.
We're delighted to have you here.
We have Wednesday Nite at the Lab every Wednesday night, 50
times a year. It's co-organized by the
Wisconsin Alumni Association and
Institute. UW-Madison Lifelong Learning
tonight. So, happy to have everybody here
two speakers on nanotechnology. The first is Kimberly Duncan.e
She's a post-doctoral associate with the Interdisciplinary
Education Group of the
Science and Engineering Center, which everybody likes to call
MRSEC.
programming and instructional materials on nano-scale science
and engineering for a variety of
Prior to coming to UW-Madison, audiences and settings.
Policy Fellow with the American DuPhysical Society's Officece
of Public Affairs in Washington, D.C.
She holds a PhD in chemistry
And Katie Cadwell, who's also a post-doctoral researcher for
the Interdisciplinary Research
She holds a PhD in chemical engineering from our fair
UW-Madison. Please join me in welcoming Kim
and Katie to Wednesday Nite at
( applause ) the Lab.
And thanks for such a great turnout tonight, especially with
the new date, doing Thursday
Wednesday, as the name of the night atevent says.stead of
As Tom said, tonight we are going to do a brief journey into
the nano world. And together, we'll explore what
is nanotechnology; what is it doing for us; and where we might
we find it in our everyday life.
acronyms and the long-winded Thankfully, Tom got all the
Interdisciplinary Education nameGroup of the MRSEC. the
The role of our group is to do
to help get the public informed educaabout nanotechnology. one,
And so, a lot of us may have
nanotechnology. And really, it's quite possibly
all around us.
see in Hollywood. Michael Crichton started a big
stir about it a few years ago,
nanobots that were consuming talking about self-replicating
We're also seeing it in the cars human flesh.
that make up the bumpers and that we drive and the materials
In our computers, as the silicon other parts of the car.
We have it in our clothes, for chips get smaller and smaller.
more messy, like myself. those of us who are a little bit
anything on and it washes right Ioff thanks to nanotechnology.l
And even one of my favorites
I know how much it really stinks is the self-cleaning windows.
and clean them off. tSo hopefully, nanotechnologyg
will prevent us from ever having
So it is all around us. We're already seeing things
about it in the media.
nanotechnology? If you're out there and you
don't know, don't worry.
only about 50% of Americans have Actually, recent studies show
nanotechnology. And a very small percentage
of those people can actually
define it. technically and correctly
formal definitions. So One comes from the federalome
government. It sounds very professional.
"Nanotechnology is the
matter at dimensions of roughly unde1 to 100 nanometers,l of
where unique phenomena enable novel applications."
And it says that it's very
If you look at the MRSEC, you'll interdisciplinary.
do nanotechnology research span noticanywhere from chemicalthat
engineering, physics, materials research, biology.
It really is very interdisciplinary as a science.
But for the public, what most of us want to walk away with is
that the nanometer is extremely small.
And at the nanometer scale, materials behave differently.
And we're trying to harness these new behaviors as a way
to come up with new and novel applications.
So exactly how small
We'll just to start off to talk about the metric system.
Some of us may remember that
You're likely more familiar with from back in school.
and the foot. thBut when thinking about theard
metric system, the base unit
I can then add prefixes to that system to say whether or not
it's bigger than a meter or smaller than a meter.
And the nanometer is
So if I took a meter stick, it's one-billionth of a meter.
and I cut it up to a billion about the same length as a yard,
would be a billionth of a meter pieces, eacin length.hose pieces
Probably, I know for me, that doesn't mean a whole lot.
It's hard to imagine exactly how
So let's try to put this in our biown cultural perspective.n.
So if I talk about a kilometer. I've got a picture of the Sears
Tower down in Chicago.
United States. It's the tallest building in the
air. It stretches 1750 feet into the
So a kilometer, pretty long. It's only half a kilometer high.
It's also the distance, if It's 1,000 meters.
the UW campus and looking down you're standing at the edge of
a kilometer to the State State Street, it's approximately
So many of you may have already walked that at one point this
week, and you'll remember, oh,
If I cut the kilometer okay, that's about a kilometer.
I get down to the meter. into a thousand pieces,
height of a bicycle seat for A meter is approximately the
If I cut that meter into a a typical adult bicycle.
down to the millimeter scale. thoIt's about the same sizeI'm
as the tip of a pen.
If I keep going down-- So, it's pretty tiny already.
things that we can And remember, these are all
If not with our naked eye, still pretty easily see.
a magnifying glass with eye glasses or
If I go even smaller, I get down to see the tip of that pen.
So I take that millimeter and cut it, again into a thousand
pieces. I'm left with a micron.
A human hair, which sort of pushes our eyes to the farthest
they can go, to be able to see
held it on end and looked down the diameter of a hair if you
That's 40 microns. the small end of it.
the micron is a red blood cell. So, It's about 7 microns.le of
These are still things we can see with a typical light
microscope that you might use in
buy at a specialty sort of a biology class, or that you can
A nanometer is a thousand times scsmaller than this..
So when we get down to the nano scale, one nanometer, we're on
the scale of atoms. So the atoms, the ubiquitous
things that make up everything
If you've gotten a virus, it's around us.
depending on the virus about 3 to 50 nanometers,
DNA, the building block of life, you look at.
are about 2.5 nanometers wide. the diameter of those helices
here on the right, if you have And this iconic picture over
might be familiar with that heard of npicture.ology, you
It's a picture of 49 iron atoms that have been painstakingly
placed, atom by atom, on a surface.
The diameter of this corral is 14 nanometers.
So, nanometer, the take away
small. definition, very, very, very
with your eyes. And so at this point, I'm going
to pass it off to my colleague
So Kim mentioned that when Katie.
cells, which are on the micron you're looking at red blood
see those using light. to 10 micron level, we can still
viruses, DNA and molecule that And we can't see things like
And does anyone know why we might not be able to see those
things using light? Any volunteers?
( inaudible ) Optical length.
Sort of.
fine enough that you could get If you could, say, grind a lens
it. alAnd the reason you can't seen
things that are down on the nano
actually smaller than the scwavelength of light.re
So light is too big of a tool to
scale. use to see things on the nano
nano scale, how is it that we're So if we can't see things on a
So everyone should have, maybe able to "see" them?
sat down, or on a table in front it was in their seat when they
And we're going to do a little of them, one of these magnets.
demonstrate how it is that we can see things that we can't
actually see using light. So each one of these magnets
has a probe strip on the end. And if you--
( inaudible ) Okay.
They're also in the back if you want one.
So you can bend the probe strip and break it off from the rest
of the magnet.
everyone to do is to take this And then what I'd like for
side of the magnet, where there's no sticker, draw the end
of their probe stick lengthwise across the magnet and then
widthwise across the magnet.
what they observed when they Does someone want to tell me
across the magnet? pulled the strip the long way
It feels smooth. ( inaudible )
pull the strip across the short And thend of the magnet?en you
It kind of bumps up and down, right?
So the reason it does this is because this magnet has been
manufactured to have a pattern
Now, when you look at the back of north and south poles in it.
the north and south poles are? of the magnet, can you see where
But I'm going to have you guys No, you can't see them.
north and south poles would look vote now on what the pattern of
could see them. So, is it all north or south
pole? Is it stripes of north and south
poles?
How many people want to vote for Or is it a checkerboard?
All right. all one pole?
south poles? How about stripes of north and
So most people think that it's And how about a checkerboard?
poles. stripes of north and south
because when you dragged the And the reason you think that is
There was no change in whether strip this way, it felt smooth.
and south pole. And when you dragged your strip
this way, it bumped up and down because it was alternately
repelled and attracted to the north and south poles.
So even though you couldn't see with your eyes, what the
magnetic pattern was on this
this probe. maAnd scientists and engineersg
use a similar technology. In general, they're called
scanning probe microscopies.
specifically, an atomic force And I'microscope.e here,
And what this does is it has a
And this tip is attached to the end of a cantilever that's
really delicate.
molecules wide at the end. And this tip is maybe a few
And you can drag it across a So it's very, very small.
forth in both directions. And as this tip goes across the
surface and encounters features on the surface, it moves up and
down. As it does that, you can shine a
laser on top of this cantilever.
fluctuations in how that And very, very small
projected into much larger cantilever moves can be
with a laser detector. movements that can be detected
today, because maybe she's a So, if Kim has a shaky hand
she's not moving her hand very little nervous, even though
see the movement further away in much at all, you can definitely
It's amplified by the distance. And by doing this, you can
actually map out surface
small scale. features down to a very, very
an AFM image from Professor Max Lagally, here at UW-Madison, of
a silicon wafer.
with me, in a petri dish. And And I'll pass it around.ere
When you look at the silicon
shiny. wafer, it looks very smooth and
And so, you can't see with your eye that there's any features
there at all. But when you use the atomic
force microscope, we can
that's below a nanometer. And these features that you see
are actually just one single
And so, using these scanning atom in width.
what we can't really see. And I'll pass it back to Kim.e
Mm-hmm? ( inaudible )
...the surface, so that you know that your disturbances
are caused by molecules,
whatever you polished it with. not by, you know, the physical
we think of as a physical Or the kindsurface.more things
I think that would have-- I can't imagine something that
would be smooth enough so that, you know, that something
detecting the surface would be
of polishing. >> So partly, we know that those
are atoms or atom vacancies because of the size that they
are.
that it will cleave. Also, silicon itself, the way
very abrupt and clean cuts in It actually silicon.ou can make
And you still polish it, but it actually likes to kind of
splinter along the crystalline
And so, it's well-known that faces.
nice, clean and flat surface, at you're going to have a very
atomic scale. lBut even on the atomic scale,e
this is really flat.
pattern. >> It's not a completely uniform
light? So are they reflections of
of light. >Because light is, you know, ans
thousand time larger than these features.
What are the stripes? There are several different
ones. >> These stripes versus the
stripes here? >> Right, it looks like a very
regular background, and then
some white. t>> This is an artificiallyd
colored image, is the first thing that you have to realize.
It's not white, black and turquoise, like it looks up here
on the screen.
map it out using a computer That was howprogram. decided to
There's no color at all, in fact.
What they've done is they've
represent different heights. used different colors to
I don't know specifically with So, usually the way they do it,
lighter colors representing this imhigher places.l have
So there's just a few more atoms
tip to deflect further from the in this spotsurface.causing that
So the coloring is completely artificial.
We've had a brief introduction to what the nano
scale is and how we see there.
Well, a lot of people are saying But what is the big deal?
revolution, that nanotechnology twill do the same thing for ust
that the industrial revolution
It will do the same thing for us did in the early 1900s.
the '80s and '90s. that the Internet did for us in
1900s versus life today, very So if we thdifferent.life in the
The same thing, I imagine.
a day without checking our email Many of us can't think of going
I apologize, I'll scooch out of or looking othe way.r the news.
The news of the day or even doing a little Internet
shopping. And you'll see that a lot of
these revolutions for technology
Railroads came around. take about 100 years.
period where a lot of Theredevelopment happened.growth
A steady climb, and then a
commonplace. plateau as railroads became more
tracks and such. We weren't building as many
thing goes for the computer Well, for taking off.Or the same
We're starting to probably
But for nanotech, we're pretty plateau for computers.
this next revolution, for nano early on in this take-off of
A lot of the proponents of to be the next big thing.
to follow this curve as it's nanotechnology think we're going
Some of the naysayers say we're going to get to about here, and
then just turn over, and
to be all hype. So it's up to you guys out there
to start thinking, is it hype or
promise. is it really a technological
saying it's going to be a big So there ardeal.ot of people
Just one quote I wanted to point
One of the reasons that people out.
deal is that it has an amazing think it's going to be a big
products that are traded on the possibglobal market.ct on
Mike Roco, who is the director
called the National Nanotechnology Initiative,
a group that's sort of involved in setting the U.S.'s trajectory
for research and development
He thinks that by 2015, nanotechnology enhanced products
will account for $1 trillion, and that in order to reach this,
we're going to need two million workers to fill the positions in
nanotechnology. So a really huge opportunity for
companies, consumer products and
And also a huge opportunity for job creation.
Supporting Dr. Roco's claim is
already started heavily thinvesting in this branch ofas
science.
the left hand side. You'll sBeing from D.C.,cies on
I'm really used to the
the agencies are represented. alHowever, you'll notice atat
the top, we're talking about
the Department of Defense, the National Science Foundation,
They're sort of the big players when it comes to scientific
research. You can see that their
investment is much heavier than places maybe like the Department
of Justice, or even the Department of Transportation.
But the total investment
$1.4 billion. So there are people out there,
and certainly a lot of
is going to be a great place to sciebe investing our money. this
Why do people think it's
It turns out when things get such a big idea?
actually matter. very, very small, that size does
see some gold and silver bars. At the top of this slide you'll
with gold or silver, either through jewelry we own or metalr
work we've seen.
bars sitting in our closets at We might not have those gold
Maybe just take a look if you have ring or earrings on to
remind ourselves that gold is shiny.
It's yellow in color. Silver is shiny.
It's gray in color. However, when you get down to
the nano scale, when you go from
nanometer, the silver and gold bulk all the way down to the
I have a picture up here. The nano particles of silver
turn yellow.
turn red. I brought a sample of gold and
silver nano particles here that I'll pass around.
Please do not open them.
I've super glued them shut, but don't try to beat
the super glue. >> If they're smaller than the
wavelength, how can there be
That is a great question. And what happens is that the
light interacts with the
way. particle in a very different
that have electrons that are So the particle is made up atoms
And then when the light wave freely roaming on that particle.
electrons to vibrate. Then they're able to emit a
color.
wavelength of light. So it is smaller than the
interact with the light. It's the way that the electrons
and think I just put Kool-Aid in So you might look at these vials
There's no particles. But I'm not that sneaky.
In addition to the vials I'll pass around, I'll pass around a
laser pointer.
in your neighbor's face as you Please make sure not to shine it
If you take the laser pointer, are investigating it.
going to try not to hit Katie in and you shine it through, I'm
nanoparticle vial, you'll tactually be able to see thee
laser pointer pass through. The reason you're able to see it
is because they're are little itty bitty particles that are
interacting with this laser.
pointer appear. To test yourself, I have a vial
of plain water. You can do the same thing.
You can't see the laser pointer go through the water because
there's no physical particles.
no particles for the light to There's interact with. there's
You can do it for both the gold and the silver.
( inaudible ) The particles are approximately,
for the silver, are approximately
50-100 nanometers large.
is a tenth of a nanometer, So if you think that an atom
of atoms. there'The gold is aboutnumber
25 nanometers in size.
nanotechnology is not really It turns out, though,
Medieval artisans have been using this technique of creating
gold and silver nanoparticles,
for a thousand years. They didn't know it at the time.
But when the artisans back in the Middle Ages added the metal
oxides and the metal chlorides
process actually caused gold and to their hot, molten glass, the
So the way that they got all silver nanoparticles to form.
adding different metals and creating nanoparticles of the
metal within the glass. They certainly didn't know
that's what they were doing.
added these compounds to the What they saw was when they
color. glass, it made this beautiful
Did I hear a question? And they put it to good use.
They're solid particles. ( inaudible )
in the glass. AThey're embedded.ed
Are there no particles
There are molecules in water. But the nanoparticles are a
collection of atoms.
explain that? >> When you're talking about
particles, we're actually talking about a big chunk of
atoms and molecules that are all
So, as Kim mentioned, your stuck together.
to be on the order of a tenth of average atom, say, is just going
And we're talking about particles that are 50 nanometers
across. So that's a whole lot of
molecules or atoms. >> Yeah?
What about colloids?
nanoparticles? Wouldn't you call a colloid like
suspension of nanoparticles. >> They are called colloidal
definition of a colloid. So it does fall under the
nanoparticles of gold back in the Middle Ages, we're also
using it today for a very dramatically different
application.
researchers at Rice University It turns out that there are
cancer using nanotechnology. who are developing ways to treat
gold nanoshell. So they take a piece of glassa
and they coat the outside of
layer of gold or, I believe they that glass with a very thin
And as they change the size or have also tried silver.
nanoshell, they get a lot of thickness of this gold
A lot like the picture I just showed on the last slide, where
we had all those different
Why does this work? Well, it turns out that these
nanoparticles or these
infrared light. nAnd when they absorb the
infrared light, the atoms get very excited because they're
being irradiated with light.
And then the scientists have And they get hot.
nanoshells can be injected into fthe body, localized into ae
cancer tumor. And then when the tumor is
exposed to infrared light, the
They increase in temperature nanoshells heat up.
were, and it causes the cells to over 30 degrees from where they
The great thing is also it's die.
light doesn't affect normal, very targeted and the infrared
We're exposed to infrared light during a regular day and we're
not affected. However, if we had gold
nanoshells within a tumor, it would cause the tumor to heat
up, the cells to die. And hopefully they're working
towards a way of treating cancer
They're just starting clinical in the future.
So this won't be a therapy that will be available any time soon.
But it's certainly a way that these nanoshells are being
utilized for a treatment. Just another example of why
size matters. Something we might be more
familiar with in our daily life is sunscreens.
I know that with my fair skin,
creamy, goopy stuff all over me. I'm constantly slathering white,
have on my face. And there's always a spot that I
the beach with a big, white, It's embarrassing to walk around
However, the way that the sunscreens work is that there's
zinc oxide and titanium dioxide in there.
And it's those particles of the zinc oxide and the titanium
dioxide that reflect the light
sunburn. and prevent us from getting a
comes from. If I start to more finely divide
those particles until they're the size on the nano scale,
again, they interact with the light differently and now the
sunscreens are clear. So you can easily buy these
sunscreens on the market now. You might have already purchased
them this past summer or gearing
Besides color, lots of other up for the summer that's coming.
scale. things change with the nano
there's also reactivity, how I just wanted to point out that
environment. reactive something is with its
on my desk, I have no worry that For soda cans, if it's sitting
in any way. But if I take the same aluminume
that's in a soda can, and I make
actually turns out to it dspontaneously combust. it
All right, so now we're going to take a little break from just
the plain old lecture and do a
I would like two volunteers from the audience.
All right, I have one.
So what I have up here is just I need a second, two, all right!
And in the bottom of each tube two plastic tubes.
I have some stainless steel is a meballs.linder.
It doesn't matter which one you take.
I promise you they are the same.
to do. Now, here's what I need you guys
I'm going to say, I'm"One, two, three, go."ee.
And on "go," I want each of you to drop your ball into one
of these cylinders. All right.
One, two, three, go.
Have you been practicing? Y( light laughter )at this.
That's amazing. You got that ball to bounce
for a long time.
and try it again. Maybe it was just your superior
technique.
Let's do it one more time. So maybe we should start over.
One, two, three, go. I'll count to three.
ball bouncing skills that led Okthat one to bounce longer.r
So what did you guys notice happened between the two trials?
Anyone? I switched the two cylinders,
right?
different. So it's not the balls that are
assistants. It's nI'm done. lovely
Thank you very much.
the two metal cylinders. What's actually different are
around. AnYou'll probably notice thatese
they're a little bit different. First of all, this one has
something glued to the top. And the reason this one has
something glued to the top
of one single metal, is the stuff that's glued to the top is
really expensive. I wasn't going to make a big
cylinder out of it. But what's actually important is
the tops of the cylinders,
stainless steel balls are anyway,bouncing against.hat the
So as I pass these around, I
surface. kind of want you to look at the
has the extra stuff on top is the one that the ball bounced on
for a really long time. And as I pass these around,
you'll notice that on that one, the one that the ball bounced a
long time on, it's really smooth
It's gotten a little bit and shiny.
in a container with a bunch of scratched up from sitting around
But overall, it's smooth. Then if you look at the one
where the ball didn't bounce as much, it has a lot of pits in
it, dents.
from? AFrom dropping stainless steelng
balls on it.
But the one the ball bounces on a long time doesn't dent.
So what's the difference
Well, the one that's all dented, between these two cylinders?
steel, also. it's just made out of stainless
the one that the ball bounced a But long time on, is made ofed,
something called amorphous
So it turns out that not only does size matter in the property
of a material, but the
the nano scale also make a arrangement of molecules down on
that a material exhibits. So in regular metals, regular
metal, such as stainless steel, the atoms within that metal tend
to form a very regular
What we call a crystalline arrangement.
And because these atoms are all arranged nicely, they can kind
of move as a group and slide
lines. past one another along fault
the stainless steel cylinder And that's what's happening to
stainless steel ball. That stainless steel ball is
taking some of its kinetic
atoms within the stainless steel energy, transferring it to the
those atoms to shift along those cylinder, and actually causing
So you get a dent. fault lines.
energy to the cylinder. TAnd eventually, it quitss
bouncing. However, with the amorphous
metal, this particular amorphous
different atoms. metal is a mixture of five
top of my head, I don't remember And I'll tell you just off the
now. what all five of them are right
together at a very high Atemperature and then cooleded
really, really, really fast.
that the atoms don't have time This metal is cooled so fast
nice, regular crystalline to arrangelattice.ves into a
Instead they get stuck with no
That's why we call it an particular form or pattern.
Amorphous means no shape, no amorphous metal.
Because these atoms are just form.
when the stainless steel ball hits this surface, it's not able
to easily dislodge a whole bunch
any clear fault lines in that of atoatomic structure. aren't
So, the stainless steel ball
creating dents in the surface, doesn't lose kinetic energy to
longer. Eventually, it's going to stop.
Some energy is lost to
You heard it as it was bouncing on the surface.
That's acoustical energy. Some of the energy is lost just
between molecules in the air. But it did bounce a lot longer.
And so some of the applications for amorphous metal, it's
already being used in sports
So you can't use it in a equipment.
golf clubs that have amorphous regulation game, but you can get
a golfer. But it's on the end of the clubt
where you hit the ball. And because you're not losing
energy to deformation within the
actually able to, in theory, hit head of your golf club, you're
these golf clubs. If you have a lousy aim, it's
not going to help you out any.
just recreational side, these have been proposed for use in
surgical metals.
someone's bone, cartilage or If you want to cut through
knife that's going to dull other tissues, you don't want a
And so, they can use amorphous quickly.
they stay sharp for a lot materials flonger.e knives and
And Kim's up again. >> So we talked about what seems
like some high-tech applications
Cancer treatment. I don't know how many stained
glass artists we have out there.
in your life already. ButI mentioned a few in thelly
beginning.
movies, and some products. I mentioned the books, the
few more products that might We're just going to talk about a
in your house. actually already have turned up
nanoparticles have an anti-microbial property.
So they kill the bacteria that
So manufacturers are now might be building up.
with these silver nanoparticles sso that the material, possiblys
on the right hand side, like a
bacteria that is starting to Tupperware, can kill the
Maybe it makes the Tupperware last longer because you don't
have things go bad in it. You don't have to throw it away.
It's also been showing up in
maybe wear your workout shirt once or twice before you have to
wash it and it starts to smell. The same thing goes for socks.
Your refrigerator.
There's even a washing machine I mentioned Tupperware.
these silver nanoparticles that was developed that had
an anti-microbial effect. in>> How does it have and
anti-microbial effect?
about how it works. But what I understand as far as
how the silver interacts, is
anti-microbial before. that silver has been used as an
sort of in older days, they would put silver solutions intod
cuts to kill things.
cells to die. What they found out with the
nanoparticles is the way to get them into materials like socks,
and fibers, and other things. >> They used to use silver
nitrates. >> That's a great example.
( inaudible ) >> Unfortunately, what
they may do is select for micro organisms that are
resistant to the materials, and then become problematic
in other ways.
to realize. There's a lot of these products
on the market.
they should be regulated. And wWhat happens to theut how
nanoparticles that are in that
What happens as you wash the washing machine when you use it?
The nanoparticles can come off socks?
water stream. in These are all really bigur
questions that scientists and policy makers across the board
are trying to figure out how
It seems like it would take an awful lot of them to clog up
any system. >> That's one of the issues.
In a washing machine, it
and millions. >> There are a couple questions.
What do we know about nanoparticles being absorbed
into our body?
of study. It is starting to get a lot more
attention.
point to certain sizes of Tnanoparticles being cancer
causing, causing other issues within cells.
There's been studies that have
other types of nanotechnology, shown that carbon nanotubes and
actually cross the blood-brain or another form of carbon, can
So these are all really big questions that people are
starting to investigate.
studies, of how much nano until And theya cell dies.xicology
Or, how much, at what size are
Sometimes the size of one gold they dangerous.
But when you get to another partsize, it is toxic.ic.
So there's a lot of questions that remain unanswered about
nanotechnology. >> Do these particles exist in
nature? Are we really exposed to them?
In some cases, yes. The carbon nanotubes I just
mentioned are actually a natural
The same thing goes for another carbon molecule called a Bucky
Ball. Again, a natural product of
combustion. Some of them do occur naturally.
Things like for welding,
that come off a weld. tThose particles are actuallys
nano-sized, pieces of metal.
there's many products that say Another thing on these products,
have any. "nano" a>> Exactly.y doesn't
A great example of that is the
( laughter ) iPod Nano.
Another one is there's It's pretty big.
with a car called a Tata Nano. an Indian company that came out
It's not nano. Again, it's a car.
comparison to any other car. But it's very small in
had it all right. They had the regular iPod and
the had the little baby iPod
Did you have a question? called the Nano.
Bucky Balls. >> Well, I've heard about
I've heard that they can trap molecules of gas in them.
Oh, I hadn't heard that.
application. But that would be a very cool
If carbon nanotubes can cross the blood-brain barrier,
couldn't they be used to help treat Tay-Sachs?
Maybe.
possible. But certainly, carbon nanotubes
have been investigated as possible therapies for different
brain disorders or diseases.
toxicology of nanoparticles is >> So, definitely a lot of the
And a lot of it is because not a unknown.
So when we talk about the sunscreens that have zinc oxide.
and titanium dioxide
point, as far as the FDA is naconcerned, zinc oxide andhis
titanium dioxide have been
materials. established as being safe
those studies to establish that, Of course, when they did all of
larger particles. And as we talked about earlier,
changing the size changes the properties.
And when I last read up on it,
But within the last year, they which has been a few months.
if nanoparticles could be wabsorbed through your skin ort
not.
was inconclusive. SAnd I think in August, 2007,h
there was a really good article in Scientific American, kind of
on this, you know, we need to be
possible impacts of doinanotechnology now. the
And specifically, they were talking about sunscreen.
So that would be something that if you were interested in
looking kind of where that is now, or at least within the last
year, you could look at that
When you talk about changing article.
combining nanoparticles and nano, tiny, tiny, together to
make a larger particle? What does it mean, to change a
nanoparticle? >> In the example of the
sunscreen, the reason that it's white is the particles, the
titanium dioxide compound, are
And so, when you start to make big.
they lose their color. them even smaller, that's when
material that we know on a macro So the change is really taking
scale, and making it small. And it's just the size change
that makes it behave
Does that help to clarify? differently.
vegetable matter? >> >> In vegetable matter? in
So, right now, when we are
we're kind of talking about talksynthetic, man-madecles,
nanoparticles.
and you're talking about If you're getting into nature,
Molecules are on the nano scale. materials on the nano scale.
semantics as to what you're going to define as being a
nanoparticle or not being a nanoparticle.
Kind of what we're talking about
nanotechnologies. >> But they might be in nature
as well.
that are on the nano scale. >> There aFor sure. in nature
Is-- nanotechnology due to
nanoparticles? technologies for our generating
time that list that we're using. Because you said that for a long
I heard that one of the Whatdriving factors in --?
nanotechnology is that we constantly want electronics that
are smaller.
regular silicon as we showed on this, there's only so small we
can really go.
smaller, we needed to come up Sowith new technologies.t
And that sort of opened up the
Also the development of instrumentation that allows you
to work on nano.
That allows you to see things at the nano scale.
The scanning probe technologies that we were talking about.
So, yeah, people have been
Medieval Ages, but they weren't mable to study them, really.he
So being able to do that makes a
And some of you may have lot of difference.
the table with the interesting already seen the little vials on
You may notice that the liquid black liquid in it.
Can anyone think of another liquid that is magnetic?
That's because there really isn't any.
( laughter )
quick movie. So I'm just going to show a
in front of you. You already have it
that using nanotechnology, we've But just another dramatic way
magnetic liquids. And hopefully, technology--
It is liquid. Next slide.
Notice that we had a pool of the
I brought down the magnet, which black liquid at the bottom.
And I think it's much better to see it when you're actually
using the vial. The resolution is much better.
So we see that the liquid is
When the magnet is taken away, attracted to that magnet.
of the apparatus. thIt turns out this liquid isger
called Ferrofluid.
invented in the 1960s, as a way to try to control liquids in
space.
particles of magnetite or rust. AnWe make these particles sony
they're only 10 nanometers in size.
We coat them with something special called a surfactant.
It just keeps the magnetite particles from conglomerating
together and losing that nano scale behavior.
So you'll see that the magnet interacts with the black
Ferrofluid just like any old
It's a lot different than maybe those hairy Harry drawing
pictures, if you've ever played with iron filings.
It looks like a solid when you
iron filings. hThe current uses for this sorte
of Ferrofluid is in stereo
external vibrations, so the music that you listen to sounds
a lot better. And even shock absorbers in
cars. You can tune, sort of the
viscosity of the degree of absorption in that
shock absorber by applying
the way that the Ferrofluid a mais interacting there.ging
Some future use that's been suggested is, again, maybe
another example of targeted drug delivery.
If I can coat these nanoparticles with some sort of
drug, and then use a magnet to
concentrate them in the part drag them through my body and
to go. that I wanted the medication
of other things Jthat might be around.es
Monolayers, which are just very thin layers.
Layers that are approximately a few nanometers in thickness
can really change the way that a surface interacts.
So this is where the
Possibly being used on bake ware self-cleaning windows come in.
If you look at the top picture, toyou'll see that that bead of.
water is not splattering out on glass like we're used to.
It's beading up and repelling that monolayer that we've laid
down. It turns out that these things
come from an inspiration in nature.
Again, we're still talking about
to special particles. The lotus leaf, or a kale leaf,
or a water lily, when you look
the water beads up. aIt enables the leaf to clean,
itself, because when the water
dirt as it travels off. It turns out that this special
beading process comes from tiny,
So these tiny bumps prevent the water from being able to spread
out on it.
tiny bumps. And with this inspiration, we've
been able to develop coatings that mimic these tiny bumps.
So we have buildings, when you
it, the water beads up and rolls put the special Lotusan paint on
The same thing for water off the dirt.
So the wood on your deck isn't repellent wood.
It's repelling the water being soaked with water.
And then lastly, that's pooling on it.
So, Dockers has khakis, that if you spill wine on them, or get
any other dirt, the treatment that's on the fabric changes the
surface of the fabric so it doesn't stain.
But rather, the red wine just rolls right off.
And you can see that at the nano
they're coated with something. scale, these fibers look,
stains interact with them and That way, don't stick.and other
I'll just also make a plug. I know I've mentioned a bunch of
consumer products.
technology behind every single And while I don't know the
there is an extensive Web site consumer product out there,
Center. I'll put that link up at the
end.
of where nano is in the products That site has created a catalog
So I'll make sure to flash that arouup.you.
There are people out there
And if you're concerned about it, you can go and look at the
catalog they've created.
to seeing some of the things >> So I thought that in addition
products that incorporate tnanotechnology, it might beer
interesting to have at least one
research here at UW. example of some nanotechnology
is in chemical engineering and I And so Professor Tom Keuch, who
grad students of his are doing think physics, also, and some
that has to do with solar cells. some nanotechnology research
of background, the basic way So just to give you a tiny bit
it absorbs energy in the form of that a solar cell works is that
It uses that energy to create a positive and negative charge
within a solar cell.
positive and negative charges to Then, if you can get those
an electric current. move to electrodes, you create
competing issues in designing an And there's kind of some
First off, you want to be able effective solar cell.
possible. And so to do that, you want to
have a thick solar cell, with a lot of whatever material it is
that you're using to absorb that
However, the thicker you make the solar cell, the more
difficult you make it for those positive and negative charges to
get to the electrodes.
make it to the electrodes efficiently, so that you can get
your electrical current, you
cell as possible. So you want to simultaneously
have a thick and a thin solar cell in order to get good
efficiencies. And what they're trying to do
is to actually design an
organic solar cell active layer. electrode where they have an
sunlight and forms these That's the part that absorbs the
But then they're growing kind of positive and negative charges.
oxide. nanopins, nanorods of zinc
electrode. And they're using that as the
zinc oxide push up into the active layer, they reduce the
length that these positive and
in order to make it to an negative chelectrode. to travel
So you can have a thicker absorbing layer, but without
having to worry about those positive and negative charges
having to go all the way through
electrode. that layer to get to an
and thin electrode at the same So you're kind of having a thick
And this is just a scanning electron micrograph, one of
those scanning probe
about earlier. microscopies we were talking
oxide nanorods. You probably can't see this text
from where you're sitting, but
that that distance is one thimicrometer in length.ting
So these are definitely down on the nano scale.
They're very, very tiny.
technology, we'll be able to And the hope is that using this
efficient and eventually cheap make solar cells that are more
them in order to take advantage enoof solar energy generationse
within their own homes and
And I think that's about all we have for you tonight.
Of course, we would be more than
We've just listed a couple Web happy to take questions.
and find more information on sites up here where you can go
There's our Web site at the very nanotechnology.
Also, there's a link here for the UW-Madison NSEC.
And if I try and say what NSEC
It's the Nano Scale iEngineering Center.g.
And the link that I've actually selected to put up there is one
of the groups that explicitly deals with risk and societal
implications. So that addresses some of the
concerns that were coming up
And the name of some regarding the consumer products.
local group that does kind of science talks, like we're doing
tonight, but on different nano
The National Nanotechnology Initiative was the group that
Kim mentioned at the beginning, the government group that's
looking into funding and
And then, the last one is the projeWoodrow Wilson Center.ogy.
They have a list of different consumer products that
incorporate nanotechnology. So, with that, I think we're
done. ( applause )
Are there any lingering questions?
How do you make the nanoparticle sized zinc oxide?
How do they make these
In particular, the sunscreen. How do they pulverize it?
They don't pulverize it.
are small enough that you could easily pulverize things down to
the nano scale. At least not and get the size
distribution that you wanted. You'd have all different kinds
of sizes and dust that you would
They actually create them from, I guess, the bottom up is the
way you would put it. I don't know specifically for
zinc oxide, because I've never
We do make silver and gold made it.
And it's just a chemical nanoparticles ourselves, though.
specific amounts of each reaction that you control the
And then you usually stop the reaction as they're growing
bigger by capping those particles off with something
that's non-reactive.
of ions? >> Do you start with a solution
What would consider the two most important applications that
have come out of nanotechnology?
sunscreen. >> Wow, I'm all over the
question. I think it's hard to choose.
There are so many.
( inaudible ) I personally find the cancer
treatment with gold nanoshells
And also, there's a lot of pretty fascinating.
purification and desalination of research looking into water
drinking water for people who live in areas that don't have
it. So I think that has a tremendous
capability to impact a lot of countries who are without clean
water.
mentioned that a lot of what's >> I think also that Kim
research is the computer been driving nanotechnology
And we didn't talk a lot about industry.
But a lot of the research has been going into making smaller
and smaller and smaller circuits.
And I think, providing that they
to be pretty important for our can make it work, that's going
What industry? everyday lives.
Yeah? >> Is there, I heard that you
could possibly buy the
The Ferrofluid? pYou can..
It's available. I think it's called Teacher
Innovations.
your dad email me, my business If you email me, or if you have
can give you the link. cards are out at the table, I
It's definitely cool. You >> We did.em.
We bought those.
Any other questions? ( laughter )
If you're concerned about the safety of some of these things,
when you buy a consumer product will you know whether
nanotechnology has been used in it?
Like for example, fabrics.
coating might absorb through Is there concern that the
Would you know? >> At this point, you would,
because they're expensive,
And they're generally proud of relatively speaking.
fabric, and it's actively advertised on the tags, or
whatever. But no, not necessarily.
A lot of cosmetics are using
You can get a little more sparkly eye shadow, and stuff
like that.
that. And >> It's definitely ansting
interesting regulatory issue. ( inaudible )
Yes.
The situation in Washington is, there's been a lot of talk
creating the right definition of nano and what is going to be
considered nanotechnology.
currently regulating it. The FDA, I don't believe is
is starting to look into The only agency that I know that
The EPA has recently started a regulation is the EPA.
companies who are producing voluntthese nanoparticles.ss for
Industry is actually anxious to have something in place,
probably in response to the asbestos debacle, where
companies were making asbestos
harmful. and it turned out to be very
pay out a lot of money in And now comlawsuits.e having to
So the problem, sort of the conundrum is that the materials
are generally already tested and
But that's at the macro scale. shown to be safe.
But there's only one agency I know that's trying at this time.
Tom?
balls, how thin could you slice the amorphous metal before you
start to lose that property?
Any idea of how many layers? You had it really thick.
need? >> How I don't know.ou would
Thank you.
No, and certainly, just to make another
plug for Science Expeditions. We'll be doing a bunch of tables
on nanotechnology, and also a science spectacular on stained
glass, where you can take home a
you stop in. piece of nano-stained glass if
All right, well thank you so Great.
Enjoy your evening. ( applause )