people on the planet who live on less
than two dollars a day what happens when
those people get sick how can they
afford to go to a doctor and take a test
and find out what what’s wrong with them
the answers to the diagnostic needs of
the patients at the bottom of the health
care pyramid can be found in our
children’s toy boxes on the kitchen
counter on the poster for this weekend’s
rave all we have to do is open our eyes
to the possibilities of everyday objects
and phenomena this map shows that the
world is a dangerous place the darker
the color of red the more deaths due to
infectious disease diseases like flu
diarrheal disease malaria tuberculosis
hiv/aids scarier sounding things like
Ebola chikungunya the Zika virus but the
other thing that you should notice from
this map is that the vast majority of
this burden resides in the developing
world in my lab we study malaria malaria
is a parasitic disease that you can
contract when you’re bitten by a female
infected mosquito the map on the top
shows the some 91 countries and over 200
million clinical cases of the disease
that occurred in 2015 the bottom part of
that map shows that unfortunately
everywhere on the planet that we have
malaria we have drug-resistant malaria
which means it’s more difficult to fight
but how can I relate the massive burden
of this disease to everybody in this
auditorium let’s try this out on a
preform well’ve
the ocean liner rms titanic struck an
iceberg at about 11pm within three hours
she sucked to the bottom and 1517 men
women and children perished in the
2015 in sub-saharan Africa four hundred
and thirty-five thousand people died
from malaria most of them were children
under the age of five that’s almost a
Titanic a day of death from a disease
that is largely curable now if James
Cameron really wanted to make a movie
about a tragedy I have a suggestion now
what could a single chemists do in light
of these massive numbers william osler
one of the founders of modern American
medicine once said there are three
phases to treatment diagnosis diagnosis
and diagnosis when you go to the
hospital with an unknown ailment you
have a full service clinical diagnostic
lab at your disposal they have the most
modern medical equipment electronic
record-keeping and some of the most
highly trained technical staff on the
planet all working with your team to
find out what’s wrong with you this is
what a full-service clinical laboratory
looks like at my research site in Zambia
Africa many such sites have decades old
hand-me-down equipment maybe there’s a
light microscope like the one you used
in high school biology class there’s no
reliable electricity the only clean
water you have is the clean water you
carry into the clinic every morning and
instead of highly trained technical
staff we have tirelessly dedicated
community healthcare workers who serve
the role as nurse technician
and public health officer this is the
world of a low-resource setting low
resource medicine and low resource
Diagnostics the buzzword around new
innovations in low-resource diagnostics
is what we call assured assured stands
for affordable sensitive specific user
friendly a rapid and robust equipment
free and deliverable if we can make
assured diagnostic devices we can then
provide the necessary health care that
our patients in low-resource settings
need the challenge we’re facing is being
able to give a patient an accurate
diagnosis as quickly as possible for as
little money as possible and assured
Diagnostics are the first step to
reaching that goal now the most common
assured device is what we call the rapid
diagnostic strip test or rdt in the most
familiar forms of this test you add a
sample blood or urine at one of the
tests and it runs down the strip like in
a home pregnancy test that you buy at
the drugstore a pregnancy test is
looking for hormones in the urine that
are produced when you become pregnant
these hormones are the test target and
over time they accumulate at the end of
the strip and they form a line the more
targets you have the dark of the line no
line no targets not pregnant but the
problem with rapid diagnostic tests in
low-resource settings is it for many of
the diseases that were interested in
these tests simply aren’t sensitive
enough that means a patient could be
sick even though the tests told them he
or she was well so how do we solve this
problem how do we make these tests more
sensitive with
making them dramatically more expensive
the answer is origami now you all
probably know somebody who’s talented
enough to fold the paper left and right
and forwards and backwards and follow
these directions and create these
amazing paper figurines you’ve seen them
the cranes whales flowers even Yoda but
did you know that origami has been used
to solve some really challenging
engineering problems it was with origami
that engineers were able to figure out
how to pack an air bag into the
dashboard of your car mechanical
engineers use this concept of paper
folding to design the crumple zones that
protect your family from an automobile
accident and biomedical engineers
designed a stent that would collapse and
be small when it was inserted into your
vein but could be unfolded and made
rigid to improve your circulation but
how in the world is origami going to get
more targets on the test to make the
test more sensitive well imagine that we
modify the rapid diagnostic strip test
one side is the test just like it was
before but on the other side we have a
filter this filter allows us to add much
larger volumes of blood or urine that
simply flow through the test without
disturbing its performance the targets
bind to the filter and when we’re done
we simply fold the filter over add a
reagent that releases the targets from
the filter the targets run down the test
and we now are looking for many many
many many more targets which produce the
line we need to tell people that they’re
sick but this isn’t the only kind of
origami RTT we can make we can make very
complicated devices that we print on a
piece of paper fold it up it’s
essentially a diagnostic
lab on paper we can look for multiple
diseases at the same time and when we
unfold the disease the the origami
structure rather than seeing a simple
test line what we have at the center is
a QR code a quick response code just
like the ones that you see in your
magazine or that on the back of a soda
bottle or advertising this weekend’s
band and using the cell phone app you
can read that QR code and it immediately
links the patient to the doctor it tells
the patient the use-by date of the test
they just took it allows us to fight
counterfeit tests we can also find out
information about when and where the
test was performed now these origami and
QR origami tests require no additional
technical skill other than the ability
to fold paper and use a cell phone
camera app cell phone camera app the
same cell phone camera app that is used
around the world they also only cost 37
cents a test to mass-produce but these
QR and origami are DTS or what I like to
think of as RTT two point oh what if you
really wanted to think outside of the
box and create an entirely new way to
make a diagnostic I don’t know about you
but for me that first cup of coffee or
first pot of coffee is a little more
important than it probably should be and
I’m not too tidy about making that pot
of coffee there are grounds on the
counter there’s maybe sugar and there’s
always these coffee rings stains we’ve
all seen them on our kitchen counters
but how are they made well it turns out
that a simple cup of coffee is not a
simple cup of
it’s not what we chemists would call a
solution what it is is the suspension of
particles your cup of coffee is full of
all kinds of fine grounds that were so
small they just flowed straight through
your filter into your cup you’ve seen
these when you let your coffee get cold
and that stuff gathers at the bottom of
your cup those are the particles I’m
talking about now what happens when you
spill a drop of coffee is that the water
begins to evaporate out of that drop and
it evaporates fastest at the very edge
of the drop so when the water is
evaporating out here at the edge the
water and the particles in the middle
flow in a specific direction to the edge
so that when all the water is gone what
you see our coffee rings it’s called the
coffee ring effect now my colleague rick
Hazleton and i realized that we could
take this coffee ring phenomena and turn
it into a biological assay for the
detection of malaria all we would have
to do is make a drop of infected malaria
blood look like a drop of coffee and so
we added special particles to the
patient’s blood that would bind a
malaria target we spot that blood on a
glass slide and as the water begins to
evaporate out of the blood the particles
with the target run to the edge now it’s
true that when it all dries it looks
like that pre-wash up there and that’s
not very clear but because the target
binds to the slide and binds to the
particles we can dip it in water and get
rid of all the gunk and what you’re left
with is a ring that ring is the same
ring that you make when you spill your
coffee and it actually means that the
patient would have malaria this kind of
10
costs seven cents to make and doesn’t
need any additional technical skill
other than the ability to spill your
coffee now the last example of a toybox
diagnostic that I want to tell you about
is about glow sticks and when my kids
were in middle school they would come
home from parties and they always had
glow sticks the kids loved the glow
sticks we’ve seen them they’re down at
the river at the fourth of July or
they’re at the party you went to last
night in my house the glow sticks always
ended up on the floor or the sofa so one
morning while I was having my first cup
of coffee I picked one up and I started
playing with it I don’t know when the
last time you played with a glow stick
was but when you play with him you bend
them they’re very flexible and you can
hear it critical and pop and you ask
yourself what’s going on and it turns
out that a glow stick is a pretty
interesting device what I discovered was
that when you manufacture a glow stick
you have an inner chamber an inner tube
and that tube is made of some brittle
material and you have a flexible
translucent outer tube and when you flex
that tube the inner brittle tube
shatters you have a compound in the
inner tube a compound in the outer tube
and when those compounds react the
product of that chemical reaction glows
you have different chemicals you get
different colored glow sticks then it
hit me I could make my very own glow
stick that could detect malaria how you
ask well it just turned out that a
student of mine had discovered a
chemical compound that when it bound to
a malaria tart
get it glowed blue no malaria target no
glowing blue color and so the idea was
pretty simple we take that brittle inner
chamber we fill it with the special
compound that binds the target we put
the brittle chamber inside an outer tube
we had the patient sample to the outer
tube we flex the tube just like you
activate your glow stick when you go
camping and if there’s target it glows
blue no malaria no glowing whatsoever so
this despite the fact that this test
works best in the dark it requires no
additional equipment to read cost about
fifty cents to produce and can be made
on the exact same equipment that
mass-produces glow sticks for
distribution all around the world now we
have to remember that it’s true without
Diagnostics medicine is blind but we
also need to realize that low resource
settings don’t just exist in the
developing world we have low resource
settings right here at home it’s a
low-resource setting at the homeless
encampment under the bridge by the river
it’s a low-resource setting in many
parts of rural america it’s a
low-resource setting across Native
American tribal reservations what we
need to be thinking about is making
effective assured diagnostic devices for
everyone everywhere and we can do that
all we have to do is play with our
children clean up the kitchen counter
and open our eyes to the every
day objects in our lives so that we can
discover new principles and new objects
which we can transform into assured
diagnostic devices thank you [Applause]