TED2017
Manu Prakash: Lifesaving scientific tools made of paper
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Inventor Manu Prakash turns everyday materials into powerful scientific devices, from paper microscopes to a clever new mosquito tracker. From the TED Fellows stage, he demos Paperfuge, a hand-powered centrifuge inspired by a spinning toy that costs 20 cents to make and can do the work of a $1,000 machine, no electricity required.
Manu Prakash - Physicist, inventor
TED Fellow Manu Prakash is on a mission to bring radical new technology to global health. Full bio
TED Fellow Manu Prakash is on a mission to bring radical new technology to global health. Full bio
Double-click the English transcript below to play the video.
00:13
So, I love making tools
and sharing them with people.
and sharing them with people.
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I remember as a child,
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my first tool I built
was actually a microscope
was actually a microscope
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that I built by stealing lenses
from my brother's eyeglasses.
from my brother's eyeglasses.
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He wasn't that thrilled.
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But, you know, maybe
because of that moment,
because of that moment,
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30 years later,
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I'm still making microscopes.
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And the reason I built these tools
is for moments like this.
is for moments like this.
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(Video) Girl: I have
black things in my hair --
black things in my hair --
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Manu Prakash: This is a school
in the Bay Area.
in the Bay Area.
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(Video) MP: The living world
far supersedes our imagination
far supersedes our imagination
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of how things actually work.
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(Video) Boy: Oh my God!
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MP: Right -- oh my God!
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I hadn't realized this would be
such a universal phrase.
such a universal phrase.
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Over the last two years,
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in my lab,
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we built 50,000 Foldscopes
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and shipped them
to 130 countries in the world,
to 130 countries in the world,
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at no cost to the kids we sent them to.
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This year alone,
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with the support of our community,
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we are planning to ship
a million microscopes
a million microscopes
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to kids around the world.
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What does that do?
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It creates an inspiring community
of people around the world,
of people around the world,
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learning and teaching each other,
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from Kenya to Kampala
to Kathmandu to Kansas.
to Kathmandu to Kansas.
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And one of the phenomenal things
that I love about this
that I love about this
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is the sense of community.
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There's a kid in Nicaragua
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teaching others how to identify
mosquito species that carry dengue
mosquito species that carry dengue
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by looking at the larva
under a microscope.
under a microscope.
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There's a pharmacologist
who came up with a new way
who came up with a new way
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to detect fake drugs anywhere.
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There is a girl who wondered:
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"How does glitter actually work?"
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and discovered the physics
of crystalline formation in glitter.
of crystalline formation in glitter.
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There is an Argentinian doctor
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who's trying to do field cervical cancer
screening with this tool.
screening with this tool.
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And yours very truly found
a species of flea
a species of flea
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that was dug inside my heel in my foot
one centimeter deep.
one centimeter deep.
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Now, you might think
of these as anomalies.
of these as anomalies.
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But there is a method to this madness.
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I call this "frugal science" --
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the idea of sharing
the experience of science,
the experience of science,
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and not just the information.
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To remind you:
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there are a billion people on this planet
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who live with absolutely
no infrastructure:
no infrastructure:
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no roads,
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no electricity
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and thus, no health care.
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Also, there a billion kids
on this planet that live in poverty.
on this planet that live in poverty.
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How are we supposed to inspire them
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for the next generation
of solution makers?
of solution makers?
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There are health care workers
that we put on the line
that we put on the line
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to fight infectious diseases,
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to protect us with absolutely
bare-minimum tools and resources.
bare-minimum tools and resources.
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03:02
So as a lab at Stanford,
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I think of this from a context
of frugal science
of frugal science
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and building solutions
for these communities.
for these communities.
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Often we think about being able to do
diagnosis under a tree, off-grid.
diagnosis under a tree, off-grid.
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I'll tell you two examples
today of new tools.
today of new tools.
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One of them starts in Uganda.
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In 2013,
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on a field trip to detect
schistosomiasis with Foldscopes,
schistosomiasis with Foldscopes,
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I made a minor observation.
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In a clinic,
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in a far, remote area,
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I saw a centrifuge
being used as a doorstop.
being used as a doorstop.
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I mean -- quite literally, the doorstop.
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And I asked them and they said,
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"Oh, we don't actually have electricity,
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so this piece of junk
is good as a doorstop."
is good as a doorstop."
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Centrifuges, for some of you
who don't know,
who don't know,
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are the pinnacle tool to be able
to do sample processing.
to do sample processing.
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You separate components
of blood or body fluids
of blood or body fluids
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to be able to detect
and identify pathogens.
and identify pathogens.
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But centrifuges are bulky, expensive --
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cost around 1,000 dollars --
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and really hard to carry out in the field.
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And of course,
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they don't work without power.
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Sound familiar?
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So we started thinking
about solving this problem,
about solving this problem,
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and I came back --
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kept thinking about toys.
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Now ...
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I have a few with me here.
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I first started with yo-yos ...
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and I'm a terrible yo-yo thrower.
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Because these objects spin,
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we wondered,
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could we actually use
the physics of these objects
the physics of these objects
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to be able to build centrifuges?
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This was possibly the worst
throw I could make.
throw I could make.
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But you might start realizing,
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if you start exploring
the safe space of toys --
the safe space of toys --
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we tried these spinning tops,
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and then in the lab,
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we stumbled upon this wonder.
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It's the whirligig,
or a buzzer, or a rundle.
or a buzzer, or a rundle.
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A couple of strings and a little disk,
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and if I push, it spins.
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How many of you have played
with this as a kid?
with this as a kid?
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This is called a button-on-a-string.
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OK, maybe 50 percent of you.
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What you didn't realize --
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that this little object
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is the oldest toy
in the history of mankind ...
in the history of mankind ...
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5,000 years ago.
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We have found relics of this object
hidden around on our planet.
hidden around on our planet.
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Now the irony is,
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we actually don't understand
how this little thing works.
how this little thing works.
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That's when I get excited.
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So we got back to work,
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wrote down a couple of equations.
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If you take the input torque
that you put in,
that you put in,
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you take the drag on this disc,
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and the twist drag on these strings,
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you should be able
to mathematically solve this.
to mathematically solve this.
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This is not the only equation in my talk.
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Ten pages of math later,
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we could actually write down
the complete analytical solution
the complete analytical solution
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for this dynamic system.
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And out comes what we call "Paperfuge."
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That's my postdoc Saad Bhamla,
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who's the co-inventor of Paperfuge.
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And to the left, you see
all the centrifuges
all the centrifuges
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that we're trying to replace.
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This little object that you see right here
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is a disc, a couple
of strings and a handle.
of strings and a handle.
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And when I spin
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and I push,
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it starts to spin.
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Now, when you realize,
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when you do the math,
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when we calculate the rpm for this object,
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mathematically, we should be able
to go all the way to a million rpm.
to go all the way to a million rpm.
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Now, there is a little twist
in human anatomy,
in human anatomy,
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because the resonant frequency
of this object is about 10 hertz,
of this object is about 10 hertz,
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and if you've ever played the piano,
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you can't go higher
than two or three hertz.
than two or three hertz.
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The maximum speed we've been able
to achieve with this object
to achieve with this object
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is not 10,000 rpm,
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not 50,000 rpm --
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120,000 rpm.
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That's equal to 30,000 g-forces.
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If I was to stick you right here
and have it spin,
and have it spin,
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you would think about the types
of forces you would experience.
of forces you would experience.
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One of the factors of a tool like this
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is to be able to do diagnosis with this.
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So, I'm going to do
a quick demo here, where --
a quick demo here, where --
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this is a moment where I'm going
to make a little finger prick,
to make a little finger prick,
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and a tiny drop of blood
is going to come out.
is going to come out.
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If you don't like blood,
you don't have to look at it.
you don't have to look at it.
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Here is a little lancet.
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These lancets are available everywhere,
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completely passive.
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And if I've had breakfast today ...
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That didn't hurt at all.
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OK, I take a little capillary
with a drop of blood --
with a drop of blood --
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now this drop of blood has answers,
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that's why I'm interested in it.
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It might actually tell me whether
I have malaria right now or not.
I have malaria right now or not.
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I take a little capillary,
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and you see it starts wicking in.
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I'm going to draw a little more blood.
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And that's good enough for right now.
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Now, I just seal this capillary
by putting it in clay.
by putting it in clay.
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And now that's sealed the sample.
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We're going to take the sample,
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mount it on Paperfuge.
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A little piece of tape
to make a sealed cavity.
to make a sealed cavity.
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So now the sample is completely enclosed.
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And we are ready for a spin.
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I'm pushing and pulling with this object.
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I'm going to load this up ...
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And you see the object starts spinning.
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Unlike a regular centrifuge,
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this is a counter-rotating centrifuge.
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It goes back and forth, back and forth ...
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And now I'm charging it up,
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and you see it builds momentum.
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And now -- I don't know
if you can hear this --
if you can hear this --
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30 seconds of this,
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and I should be able to separate
all the blood cells with the plasma.
all the blood cells with the plasma.
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And the ratio of those blood
cells to plasma --
cells to plasma --
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(Applause)
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Already, if you see right here,
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if you focus on this,
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you should be able to see
a separated volume
a separated volume
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of blood and plasma.
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And the ratio of that actually tells me
whether I might be anemic.
whether I might be anemic.
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One the of aspects of this is,
we build many types of Paperfuges.
we build many types of Paperfuges.
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This one allows us to identify
malaria parasites
malaria parasites
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by running them for a little longer,
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and we can identify malaria parasites
that are in the blood
that are in the blood
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that we can separate out and detect
with something like a centrifuge.
with something like a centrifuge.
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Another version of this allows me
to separate nucleic acids
to separate nucleic acids
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to be able to do nucleic acid tests
out in the field itself.
out in the field itself.
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Here is another version that allows me
to separate bulk samples,
to separate bulk samples,
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and then, finally,
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something new that we've been working on
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to be able to implement the entire
multiplex test on an object like this.
multiplex test on an object like this.
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So where you do the sample preparation
and the chemistry in the same object.
and the chemistry in the same object.
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Now ...
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this is all good,
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but when you start thinking about this,
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you have to share these tools with people.
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And one of the things we did is --
we just got back from Madagascar;
we just got back from Madagascar;
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this is what clinical trials
for malaria look like --
for malaria look like --
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(Laughter)
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You can do this while having coffee.
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But most importantly,
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this is a village six hours from any road.
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We are in a room with one of the senior
members of the community
members of the community
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and a health care worker.
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It really is this portion of the work
that excites me the most --
that excites me the most --
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that smile,
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to be able to share simple but powerful
tools with people around the world.
tools with people around the world.
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Now, I forgot to tell you this,
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that all of that cost me 20 cents to make.
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OK, in the negative time I have left,
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I'll tell you about the most recent --
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(Laughter)
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invention from our lab.
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It's called Abuzz --
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the idea that all of you
could help us fight mosquitoes;
could help us fight mosquitoes;
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you could all help us track our enemies.
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These are enemies because they cause
malaria, Zika, chikungunya, dengue.
malaria, Zika, chikungunya, dengue.
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But the challenge is that we actually
don't know where our enemies are.
don't know where our enemies are.
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The world map for where
mosquitoes are is missing.
mosquitoes are is missing.
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So we started thinking about this.
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There are 3,500 species of mosquitoes,
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and they're all very similar.
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Some of them are so identical
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that even an entomologist cannot
identify them under a microscope.
identify them under a microscope.
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But they have an Achilles' heel.
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This is what mosquitoes flirting
with each other looks like.
with each other looks like.
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That's a male chasing a female.
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They're actually talking to each other
with their wingbeat frequencies.
with their wingbeat frequencies.
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(Buzzing sound)
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And thus, they have a signature.
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We realized that using a regular phone,
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a $5-10 flip phone --
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how many remember what this object is?
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(Laughter)
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We can record these acoustic
signatures from mosquitoes.
signatures from mosquitoes.
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I'll tell you exactly how to do this.
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I caught some mosquitoes outside.
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Unlike Bill [Gates], I'm not
going to release them.
going to release them.
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(Laughter)
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But I will tell you how
to record from this.
to record from this.
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All you do is tap them and they fly.
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You can first test --
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I can actually hear that.
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And you bring your phone,
which has microphones --
which has microphones --
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it turns out the mics
are so damn good already,
are so damn good already,
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even on regular phones,
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that you can pick up
this near-field signature.
this near-field signature.
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And since I'm out of time,
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let me just play the recording
that I made a day ago.
that I made a day ago.
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(Mosquitoes buzz)
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This is all the charming sound
that you heard before
that you heard before
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that you all love.
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One of the contexts of this
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is that being able to do this
with a regular cell phone
with a regular cell phone
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allows us to map mosquito species.
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Using a flip phone,
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we mapped one of the largest
acoustic databases
acoustic databases
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with 25 to 20 species of mosquitoes
that carry human pathogens.
that carry human pathogens.
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And from this and machine learning,
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anybody who uploads this data,
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we can identify and tell the probability
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of what species of mosquitoes
you're actually working with.
you're actually working with.
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We call this Abuzz,
and if any of you want to sign up,
and if any of you want to sign up,
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just go to the website.
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Let me close with something
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that's very important
and dear to my heart.
and dear to my heart.
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One of the challenges of today
is we have terrible problems.
is we have terrible problems.
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We have a billion people
with absolutely no health care,
with absolutely no health care,
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climate change, biodiversity loss,
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on and on and on.
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And we hope that science
is going to provide the answer.
is going to provide the answer.
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But before you leave this theatre today,
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I want you to promise one thing.
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We're going to make science accessible --
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not just to the people who can afford it,
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but a billion others who can't.
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Let's make science and scientific
literacy a human right.
literacy a human right.
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The moment that you pass the tingling
feeling of making a discovery
feeling of making a discovery
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to another child,
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you're enabling them to be
the next group of people
the next group of people
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who will actually solve these problems.
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Thank you.
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(Applause)
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ABOUT THE SPEAKER
Manu Prakash - Physicist, inventorTED Fellow Manu Prakash is on a mission to bring radical new technology to global health.
Why you should listen
An assistant professor of bioengineering at Stanford University, Manu Prakash is a physicist working at the molecular scale to try and understand no less than how the world really works. As he told BusinessWeek in 2010, he is humbled and inspired by nature’s own solutions to the world's biggest problems. "I build and design tools to uncover how and why biological systems so often outsmart us. I believe one day we will be able to understand the physical design principles of life on Earth, leading to a new way to look at the world we live in."
Born in Meerut, India, Prakash earned a BTech in computer science and engineering from the Indian Institute of Technology in Kanpur before moving to the United States. He did his master’s and PhD in applied physics at MIT before founding the Prakash Lab at Stanford.
Prakash's ultra-low-cost, "print-and-fold" paper microscope won a $100,000 grant from the Gates Foundaton in 2012.
Manu Prakash | Speaker | TED.com