It's very very pleasure like to introduce
it is the single with pleasure professor.

To do a special.

Instruction for
the day it's about two years ago

I was still a post-op press
room trying to get a job.

But we really want to get rid of me
Georgia Tech was nice enough to take me so

everything worked out.

Great is really going to see significant
presence in the home are signs that.

He's working to mark the white
range of topics getting a lot of

areas all of the Center for.

New ways to approach making materials and
making.

Things work I never areas
both industrial and

academics spend a significant time I hear
work join the Army just for work and

it's really change the perspective
on all of science for both don't go.

Back to the tax breaks.

And really does mean credible innovations
all the way going all the way back to when

you suppose not pushing the revolutionize
the way people are on the bright

colors inventors then when she would die
young interesting completely new type

of control radical rejection I caught
sight of his age when we went to U.C.

Santa Barbara very pleased with
adopting new ideas of click and

change the way people bought
about how many materials homers

use these things building blocks in
themselves open up the doors and create.

The most recent years to see any area like

conversation with me now OK you know
the selling point of calling the very.

First time you are with me and

I think he's really smart display or just
he's been involved in a lot of different

successful startup things
like the looks of.

But the most natural honest
person country guys walked in and

saw your house right here.

You can tell you can touch it and
feel it if you want will really like.

And that's because it's what.

You're all about which is actually
taking the entire world but

it is now over three hundred
seventy thousand long.

It's wonderous odds over
the years it's been

used by most celebrities that
you know sometimes it's.

For instance you could actually
just we did that because.

You realize just recently she went
like this like crazy for yes.

Character doesn't make.

Any Carly you want my friend and
guess what the first time for

you first times free.

I want to hear from.

Her the same second yes it's really
great to go through all the success rate

you really get your first words with
them all name a couple is one word

on the screen for
my younger son works toward.

The roles I used to look at.

And the list goes on.

But off we see it's a pretty good guy.

Using your version and like to be.

Here.

But soft spoken.

To the everyone in the pleasure
to be here today and I like.

Dory will you because.

You didn't know who he was by.

Realizing that here.

And so I like your feelings
here in the land I will go

back to Santa Barbara but the M.R.O.

which is where we'll spend most of these
time is around about here it's hidden

behind this building and
we have a Christmas party and the biggest

while we all watch this and you can see
it's true because we're starting to read.

How big a soiree with
the Christmas party at the M.R.O.

was not whether we had enough
food whether we had enough drink

was what was going to do and

where was will going to end up
because the challenge was the.

Christmas party will go into the evening
and we dock outside and here are cliffs

and it's cliffs down to the beach and
on more than one occasion and

we're not talking about fifteen twenty
Christmas parties to will where

I talking about three Christmas parties so
he has a really good success right

all disappearing dring
the Christmas party and.

All of this then having to look for him
because we were concerned that he would he

handle the Christmas parties so badly
that he would just simply walk out and

fall down and we'd find him on
the ocean in the morning and so

I'm really happy that he survived
the Christmas parties and

a look at him gee right in the eye and

never hold the Christmas party when
he's in town OK you have been warned

That's right make sure there's no
water body anywhere around will

around the Christmas party so I'd like
to tell you two short stories today

in the general area of bio
inspired materials but

I'd first like to really think
Miller Paul sigma for supporting

chemical research throughout the United
States and actually throughout the world.

It really isn't one of the research and
I will now show you how all

I am by telling you exactly
what I still look for

from Miller pore Sigma and
that's the chemical catalog for

many students in the room you've
probably never actually touched.

The old rich catalogue but
this is a very very thick book and

as a student I would actually
look through this and

it was I really miss it he's some
feedback for you guys I really miss it

because you'd find the chemical that you
were looking on a page and guaranteed on

the next page all the opposite page they'd
be another chemical that you'd see and

you'd order up and so this was a great
heaven you not only to discover

compounds but
to order even more chemicals and so.

Orders chemical catalogue
will always be in my hot and

the other thing is I always used to
love these ads from Alpha who was one

of the founders of the orders chemical
company and please please bother us and

again this is something that
Aldridge brings to the community and

that's all of these unique chemical
compounds that other people find

extremely useful and this is going to be
a theme throughout my lecture today and

it really was inspired by our
initial collaboration with with M.G.

and Barry shoplifts was that
making chemistry simple and

decreasing the activation
energy is really important and

having Aldridge supply all of these
all middle posting there I apologise

all of these chemicals is really
actually really tremendously useful So

these are the two stories I'm
going to tell you bet today

the first is the development of
a new class of it he's eaves and

the second is instruction in a particle's
again the common thing that I want

the students to take away
is using simple chemistry

true Mike materials with application and
with purpose and

so both inspired by marine organisms the.

First by simple muscles and
the second boy cuttlefish So

if we look at the first area and
this is in underwater and

he's eaves walk in to tell this well
this was really inspired by a colleague

of mine in the Marine Sciences Institute
a White who's been studying muscles for

the last thirty to forty years and
Herb is a biochemist so

he tries to understand all
the biochemical underpinnings of

what the muscle does and then where we
come into the picture is to try and

train slight those understandings
into actual synthetic materials and

so this is what Hood has discovered
over a number of years and

that is the must all prepare is
two types of catatonic peptides

a cat on a set of Pip tides and
a separate set of Ed

on it peptides both of
these are water soluble but

what it does next I
think is really smart or

I was going to make a political joke
because you know this is a real genius OK.

And what the muscle does is
that it takes these two water

soluble all you want to pick
tides mixes them together

in a special chimed in its body
to form what's called a CO S.

of eight which is Ward it insoluble so
that's the first trick

it's taken to water soluble materials and
made a water insoluble material but

from a material science viewpoint these
coercive eight systems are really

exceptional for
that he should they share thinning

the organism can easily spread it
out of the orifice that it uses

has low into facial energy so it's
spreads readily over the surfaces that

can be extremely by a fair out and then
it has high frictional coefficient and

secondary chemistry which we were
exploited Lyta that allows you to

cross link and sit here and
he's Eve so comes that sticky and

ends up being an extremely
stable under water and

he's live again starting from
water soluble materials and

it does this through a lot of the same
really of structure in water and

two key structural motifs the coalesce
of that I'll go on in a second but also.

Modified peptide Torah scene
which is modified to dope

in essence think of it as a cad
a coal unit and it's this also Di

phenolic unit that is really really useful
from an adhesive point of view as well so

these are the mind to structural
motifs that muscles and

a lot of other marine
organisms use to survive

in a hostile environment if the muscles
don't get here to the surface they die

there is a really strong incentive for
them to actually use this chemistry and

use it will as I said the other thing
that I want to get across to the student

is that from the simple
building blocks we can assemble

a large range of structures
in a solution and

this is something that many people
here at Georgia Tech do and

that is looking at the assembly
of different systems

in water typically a mixture
of chaotic systems and

on an existence allows you to
create larger structures and

provide more powerful
properties to the systems

than the single systems alone so again I
just want to kind of bring out the work of

else a poll Jennifer Blair
in also looking at

these are your own existence and so
what would we like to do well we

want to look at these coercive eight
systems to make synthetic materials and

our first test case was
can we make hydrogels

that have significant physical properties
and mechanical properties but on.

Bonding and
essentially based on these Co S.

of A interactions so you can think of
these is similar to them a plastic

elastomer as on the soles of all of our
shoes these are non cross-link systems

in the terms of your shoes they held
together by glossy polystyrene domains

in this case we're going to have hydrogels
held together by the water insoluble

coercive phase and so again we start
with water soluble materials and

we end up with water insoluble but
swallow bull Hydra job and

so this is some work that Jasmine and
Jason did a number of years ago.

And Jason I had the very smart idea
to start from a common stock to

try block Coppola So
we have one block a central block and

another terminal block so that we could
really do structure properly relationships

since we're going to mix two things that
have share a common starting material so

using chemistry that I'll go over in
a minute Jasmine and Jason were able to

functionalize the terminal blocks
with author catatonic units or

an eye on it units in such a way
that we have the same number

of catatonic units at both ends but
also the same number of and

only on it communities at both ends as
the number of cattle and units and so

we can really balance
the charges if we want to or

on balance the charges if we want to so
we have a lot of structural control over

these systems so again a plug for Aldrich

they supplies to really useful
starting with truly cheaply and so

we start with polyethylene glycol as our
central block how key building block is.

Up which is dirt cheap we
love things the cheap but

it carries a lot of functionality
it has the POC side and

it has the alkane Typically
this is used in industry put

through the keen to give poly sides we're
going to actually turn it around and we're

going to do ring opening pluralization
initiated from the polyethylene glycol

all the Apoc side to give these I B I try

block Coppola's in which we
have terminal units that have

a lot of alloy units so a lot of
double bonds that we can secondarily

functionalize So this is going to
be a common starting material and

as you can see here we can control
the molecular weight we get low poly

dispersed the materials the polyethylene
glycol is cheap and the.

Thing is also very cheap
we can actually make this

on multi gram Scouse I think our largest
scale is about two hundred grams

because you don't need solvent for this
pluralization And so this is a bad is easy

to get you simply take
your SIL ether add it to

peg in the Plumber zation the Shiites when
you have the potential potassium salt.

And so this is where chemistry
comes in because now we have

all of these Hello units along
the backbone we need highly

efficient chemistry to functionalize those
we want to put a lot of function different

functionalities on without protecting
the protecting chemistry we also

cannot purify these functionalize
try book Coppola miss so we need

efficient chemistry that's compatible for
a lot of functional units and

again this is where the concept
of click chemistry comes in and

I took this from the total
of M.G.'s two thousand and

one paper where he and

Barry introduced this
concept of chemistry and

this pipe I don't know whether you've
looked it up recently has been signed to

approaching ten thousand times and
so you know this is

probably one of the highest cited pipe
in the last twenty to thirty years and

so this is really impacted a lot of people
in this really impacted all of the work

that I'm going to show you
the softer noone has also used

other click type reactions to put
together the materials it really is so

simple that I am hoping now that Natalie

has left Imperial College that
she will become a synthetic

chemist and stop making all who
materials with chemistry OK And

so we exploit thought Eileen
chemistry as you can appreciate to

functionalize all of these units and
again it's a quantitative reaction and

as I show you we can introduce a wide
variety of functional units with that

protection D protection chemistry so to
cut a long story short we made a whole lot

of different materials where we had
different cattle ya Nick units and

different and ionic units and

then we start to mix these to see whether
we see any impact from not only the number

of groups but also the night of
the on the ON IT groups and so

again cutting a long story short when we
have these tribal Coppola misfunction

Elias with primary amino groups all
come to groups you mix these together

in water nothing happens you don't
get any increase in viscosity and

so there may be some association but
it's not leading to any useful properties.

When we swap the casket with the SO

FUNNY tested you get a slight
increase in the scar city but

still it really is not a useful
increase in performance and

so it's only when we go to
the going to do any M and

the cupboard Cassatt that
we actually start to get so

we're making a hard job but
in this case it's really soft.

Has the mechanical properties
similar to Jell-O.

and so it's not it's but again it's not
going to give us any of the mechanical

performance that we want only when we
go to the GO ON A Deanie M and the SO

FUNNY Cassatt do we get a tough Jill that
actually is I'll show you in a second

is so tough it's actually hard to
cut it with a rise of blight and

so the difference in physical
properties simply biased

by choosing the groups is
really actually significant and

we will stop to see that we can go
from something that has the scarcity

of water to something that you can't
cut with the rights of blood and so

the other thing that was really surprising
about all of this in retrospect

maybe we should have expected it we
didn't expect all was how quickly this.

Is And so this is an experiment
the Jasmine was doing we have one wait

percent solutions of
the Caddo on it try block and

the an eye on it try block in water
there's simply different colors because

they have Ph indicated in them Jasmine
sucks up the gun a dinny a material and

by the time she squirted it in
to the end on a try block and

mixed it it's jailed these
things exceptionally quickly and

in retrospect this is
understandable from two reasons.

The muscle is not going to wait around for
die for

it's coercive to form it needs to
survive so it needs to do it quickly and

we're talking about ionic bones and so
they're going to associate very quickly as

well and so we were surprised
that this form so quickly but

the thing that was even more surprising
was one when Katie looked at the structure

of the system so this is the you
can think of it as the crude

Hydra Joe that we form when we mix either

end on a concurrent try blocks that have
a middle polyethylene glycol of ten K.

twenty K.

or thirty five K.

together and
then looking at the structure that you get

that is immediately form so
there's no one kneeling here

this is the structure that you get and
you can see that for the ten K.

and the twenty K.

especially we get very long range
water out of these systems and so

we get these assembling into
these spherical done mines and

then those domains
assemble many many orders

of repeats so
that we have this cross-linked but

not chemically cross-link hydrogen where
the matrix is ninety five percent water

it's wall and polyethylene glycol and
it's held together by the spherical CO S

of a domains which interesting
really somewhat hard to fill it.

Somewhat hydrophobic there about thirty
five percent water obviously not saw

a balloon water but so show you they
do have enough hundred felicity

to soluble lies small organic
molecules which again we've used for

drug delivery system so this was really
surprising that they form with such

a high degree of long range order
the other thing that was interesting

was that these samples extremely
robust not only to temperature but

to also on it content so
many systems use ionic screening

to stop coercive bone formation
in this case you can see

that as we prepare these hydrogels
we can choose in their performance

by choosing the number of oil
on it groups in each domain but

also by swelling them in
this sodium chloride or

hot water we see very little change
expression as we go to D.P. thirty and

forty and so seawater is much less
than one mole a sodium chloride but

this shows you that even with that
high degree of salt that these

coercive domains are stable
under these conditions and

we don't screen on a CLI
the bonds that form the bonded

interactions that stabilize these
hydrogels So the one thing I

insinuated a number of times already is
the degree of control that we have in

these systems so as I said before we
have a common starting material so

that we can match the number of oil and
groups but

we don't have to do that we
can actually do a mismatch so

that in this case we have had on
it try block and we mix it with.

Really decreased amount of the and
ionic try block and then some I honestly

will and ironically chacha small molecule
Kaga with the idea that hopefully

these will form a hydrogen but
incorporate our desire.

Into the CO S.

of A domains and release that over time so
think of this as a delivery system for

a range of different charge materials
the other thing that this in C.

This implies is that if we
could make this into a mock or

Jill it may actually be more
easily implanted into the body or

taken through the G.I. track and so that's
exactly what we wanted to do in this piece

of work we wanted to answer these
two questions can we include go and

can we make something other than
a slab of hard to chill and

so to look at that we turn to.

Michael fluidics.

The idea being that we have night Paul and
it dissolved in water going to Denny and

Palmer dissolved in water and
in a model fluidic device and

taking advantage of the really
fast speed these things jail

can we simply make spherical
particles that during the residence

time in the model fluidic device will
actually Jill and become stable and

again I want to really cut
a long story short and

in a mixing channel that has arisen this
time of less than a minute you can make

these spherical particles that
you can collect in the outlet and

these are now stable they
are held together by the CO S.

of a bonding they do not clump and
this stable for long periods of time and

we can also form these in
the presence of various Cod goes I.

Cast the.

Self on a castle and a tryst so funny
casts that you can see here that the model

for the way the device actually really
does allow us to control the diameter

all of the big pot of coals and
in the and then our skull Picco S.

about domains we can get fairly
high loading all of these.

Up to twenty percent and

then these Cod goes can
be released over time and

they release right as you express it
is really dictated by this structure

the more I own it groups the slower
that there were at least so

funny classes are released
slower than comp oxalic acid so

you can really showing
your release profile based

on the structure of your car go and
the structure of your original try block.

And so that was the stories I wanted to
tell you using direct mimic of the CO S.

of a formation where instead of peptides

way using synthetic Palmas but
night is somewhat limited

the muscles can use peptides pick tides or
peptides but

as synthetic chemists we're not
limited to organic materials so

this is one project that we
did in collaboration with.

At the University of Tokyo where
we asked a simple question.

KNIGHT You cannot use inorganic materials
they limited to peptides as I said

can we actually start to use in only
inorganic materials and actually Mike

hydrogen that has significantly different
properties to the organic one and

it's actually quite simple to do
here we have the same carry on to

try block that I showed you before
polyethylene glycol made block one a D.M.

groups at the end and
instead of using the corresponding N.O.I.

on it try block we're going to use
an eye on it client in a sheet and

so the idea is that we're going to have

the trouble of Palma essentially act
like a bind up binding to the surface

of the clay sheets and
bridging the clay sheets to again give us.

Cross-linked hydrogen but you can now
think of this is being plated since

instead of purely organic systems
we now have these very stiff

clay Nana sheets in these materials
they are transparent because of

the dimensions of the client in a sheet
but we do see a significant improvement

in performance for
the all organic system we have G.

prime and D.

double prime a random ten to the three
tenths of the four in this case

we got about a two orders of magnitude to
three orders of main chute increased in G.

prime and double prime by simply
using the client in a sheets

instead of the polyethylene glycol based
try block Coppola as I said before

you know these things stream Lia robust
This is actually a rise of blade and

you can see that you can put a significant
degree of force on the rise of blade and

it's not cutting the hydrogen even though
the hydrogels about ninety seven percent

water the other nice feature is
that these materials still have

the robustness that you would expect
from a organic harder job and

so these are really interesting materials
one of the things that your highness and

Jeff was able to show is that these
are robust These are tough but

remember these are not covered systems so
they should sail heal and

that's exactly what they did
they looked at the mixture

of these catatonic try blocks
the client in a sheets and

it's a real study where they
look at the real they then.

Put a lot of stress on
the system we get Strine we get

recovery we constrain and again it
recovers we constrain it again and

it recovers and you can see that the self
healing or the recovery time is again

very short that's tracking the quickness
that these materials are formed by and

we recover to approximately the same
properties that we saw before this

is really kind of easy to understand again
biased on the fact that we're using on it

Bones which if you pull them the pot
will find each other again and

really heal and reform and so we did
a number of cute little studies with to

KUSA where we cut things we
put them back together we D.

swelled and then REESE Well and so

again these have really good self healing
properties driven by the fact they're not

bad not based on cross links that based
on physical cross links and on and on.

And so that was the first structural motif
that I really wanted to tell you about

today the second structural
motif is really based

on some chemistry that that
will brought to the table and

so again very cheap
starting with truth about

Yes So so
this is the this is the before picture.

This is the after all flicks picture OK so

I won't be selling it outside
off of the lecture and

if you just feel you if you buy one
you get the second one free OK and

we'll throw in shipping so so
if you look at that cattle call group

a really nice functional functionality but
doper itself is extremely expensive and

so we wanted a much cheaper
functionality that allowed us to

access these cattle call units and
huge an all or

clove oil is as you can see really very
very cheap also makes the lab smell

on believed to be good and so this was
the starting material that we wanted but

from a synthetic chemist viewpoint you
know it's a bit of a challenge we have

one free phenolic group one
protected is the metal ether it

does have the a little like double bone
that we want so it's almost there but

it's not really there and if you look
at all the protection the protection

chemistry is a valuable nothing really
worked very well but will come along.

And took out the next slide OK So
we'll come along and

I was going to promote some of what
Will's other would just looking at again

using cheap styling materials in this
case saccharin to build quite complex

macromolecules but since Will's been nasty
to me I'm going to pos over this work and

show you again a photo of
the younger will and so

this is the chemistry the Will brought to
the table that we can take you to know and

treat this with a variety of different
sidelines in the presence of this Boron

trist pencil Fluor fennel catalyst
is a room temperature reaction

no solvent Natalie could
do this really easily and

get very very good yields of a protected
derivative so we've not only got rid of

that method which is rube although we've
protected it we've got a quantitative

yield we can do this on very high scale
it's a room temperature reaction and

now we're perfectly set up to start
incorporating this building block

into a variety of different poll
America's systems and have the.

Catacomb very easily obtainable by
simply as a deep protecting the SOL.

So again one of the chemistry's
that we've used a lot is

the thought I'll addition to this
double bond with a lot of these

sawlog same derivatives that have
thought all groups off the back burner

again we can vary the number of catacombs
along the backbone the molecular weight

of the backbone this is all quantitative
chemistry that works very well and

now we can start to use
the excess thought well to cover

cross-link these systems so
in this case we use some thought

I lean cross-linking chemistry these are
all well studied materials and if we add

shootable amounts of this thought
derivative that has the chemical units

we can actually functionalize
silicones where we

have controllable amounts of catacombs
just waiting there to be exploited.

We treat this one facet we protect and
now we have these that he is the groups

that I told you about before
that who was able to show

really had he had strongly to surfaces and
so

just to prove this if we look
at these catacombs surfaces and

compare them on so essentially we
make a pure chemical surface and

then deposit these gold squares
on top if we go across this and

measure the IT HE Asian to a silicon
dioxide probe as we go across

it really correlates very nicely we get
stronger he Asian where we had to catapult

we get no wood he's in where we have the
gold we can do a similar experiment way

instead of gold these Nandi protected had
a coals and they get very similar behavior

only when you have to cut a cold do
you have the to the oxide surface and

so these are just some pretty
experiments that we decided to try where

we take silica we
functionalize them a stamp

with the chemical units and
see whether we can pick up these beads and

how strongly these beads are and
he had to the surface so

these are silica be aides and
we've fabricated these little.

Cylinders and we can either have
protected catacombs at the surface or

non protected free catacombs and
just to cut a long story short

when the chemicals are protected
you can't pick things up but

I was very very easily because you
just use ing Vanda Wells forces

to pick it up but there's nothing really
sticking the beads to the Pillas But

when we have the freak out a cause even
when we all just on the Cape these

the beads a stuck to the catacombs units
that are on the solid sign pillars.

This actually then starts to allow you
to think about capturing things so

imagine you have a surface where we have
predefined areas that we have had a coast

and other areas that we don't have had
a cold can we simply flow a solution

of silicon beads over the top and
start to capture the silicon what is

delicacy of capture does it happen
everywhere we have Cata calls or

only occasionally so that was
the experiments that decided to look at

this is has stamps if you can capture
the beads with really high fidelity and

even very very small structures so
these pillars that as you can see

are about five mark crones
in diameter the surface of

these have the free Cata calls and
again these capture the silica be

by simply flowing over the top very
very easily so the final thing

I want to show is that we can actually now
use these Catacomb as well as the CO S.

of chemistry to actually make some and

he's lived very much mimic a marine
organism and the marine organism

the sandcastle wombs which are found
off the coast of Santa Barbara and

they're fascinating creatures
that form the habitat to protect

themselves from predators and
so what the animal does and

you can see it here it makes these choose
by simply taking sang grains rubbing it on

all going in the chest and that organ
then puts a little bit of it he.

That is based on coercive chemistry
as well as Quetta calls and

then sticks those saying grains
together so that they have a little

Ahmed helps in amongst all of the end
of the animals that want to kill it.

So.

And I should say I was not involved
in these experiments at all but.

Stressed the same cost
a woman out by making them

build their houses out
of spherical silica B.

instead of saying grains
this really stresses

the sand castle rooms and
they want these irregular.

Sand grains if you give them the choice
they will never pick a spherical

silica particle might have something to
do with the mechanics into locking but

you can get them to use
spherical particles and

you can see here the little
bit of glue that they put and

used to stick the silica
particles together so

this is how the same castle works and
this is the set of experiments that in

June why did she talk to silica
bees that I showed you before and

then the Cata called Paula again
that I showed you before and

simply had a solution of the two so
that the silica particles

had here some of the catacombs which
undergo deep protection in solution

to the surface and
now she has the silica particles

that have these cattle call groups that
have additional Cata calls as well

as freeze thaw oils attach to
the surface she then takes these B.

and one by one puts them
with the surface coating

into a solution that let me get.

That has ten million dollars of
sodium pariah date and this is two.

Stott cross-linking chemistry that
night she uses nature uses an oxidative

chemistry as I'll show you a second
to cross-link up the particles and

the chemistry that we've put on the
surface and so she does this one by one

and slowly but surely builds up the
cylindrical habitat that is very similar

to what the same kus a worm does and again
you can see here the secondary chemistry

that the sodium Polaroid they
initiate that allows us to stick

the chains together which in turn
stuck to the surface of the silica

particles and
cross-linking is absolutely key for

the stability as is the presence
of the free Catacomb unit so

this just shows you an image of
the cylindrical habitat that

gene while was able to make the same class
a womb is actually happy to live in there

but the key is that in
the absence of pariah date or

if you get used protect the catacombs
you cannot make this habitat at all.

With just the slightest knowledge and the
same Casa womb will also as it goes in and

out will destroy it and so
this was really nice example of

not only using secondary chemistry but

was an absolute expert with chopsticks and

I tried that with that was how she
placed the be in the solution I tried

to do this and I could get up to a bet to
lie and everything just fell apart and so

this was really nice use of that chemistry
again inspired by the marine organism so

in the last five to ten minutes I'm just
going to tell you a very short story about

some structured nanoparticles again
inspired by marine organisms in this

case the cuttlefish again
that's a strength of Georgia

take looking at structured in
a particle and structured and

functional particles we're
going to take advantage of

particles that is somewhat similar
to what Todd looks at with respect

to having lie is in this case these
generous particles we're going to try and

make particles that have more than
one law is and so this was inspired

by a collaboration with Dan Morse who's
also in the Marine Sciences Institute and

then has been studying for a number of
years cuttlefish which are absolutely

unbelievable with respect to camouflage

this is what the cuttlefish looks like
when it swims normally when it settles

down on the surface you can see that
it mimics what's underneath that.

Almost perfectly Hal these animals
do this no one really knows but

what they do know is how they
choose the color on this

surface and it's done using
these specialized sales called

really a full cells which I'm showing
you here and if I just showed you this

photo with that telling you that
these are Radio four cells and

you are in the poem a science community
you'd say well that's a Lamell a die block

obviously they're not what
they are protein platelets

that a separated boy extracellular
space there's a small we frac to in

the difference between the protein and
the extra So you'll fluid and

what the organism does is it just
swells the protein platelets

by a very small amount but that amount is
enough to impact the brag reflection which

allows it to choose the color so if it
wants a dock it colors a little bit more

light a color it doesn't swell as much and
so these this is how these cuttlefish and

a lot of other marine organisms actually
do camouflage and so again we wanted to

see with that we could learn anything by
translating this to synthetic systems so

I'm going to go over this relatively
quickly as I said when we look at this

we don't see Radio four cells we see
the M L A die block Coppola MS So

when we wanted to make instant that
equivalent of this we thought can we make

spherical or ellipsoid shaped
particles from a block of Palmas

have them face separate to give us
the M L a dog walker problem is and

then we can can we swell those.

Block of pollen is one of the biggest
challenges that we initially

had was to make ellipsoids an ellipsoid.

Orientation of the dog.

For a number of years and not lying
a number of years we looked at taking

solutions of dog block of polymers
evaporating them down to give us and

in every case we've got
spherical particles and

as you can see they have a structure like
an onion exactly what we don't want and so

we were stuck in onion land for
a long long time and

everything we tried gave us onions and
SFI is and

so at the same time we were doing some
work with crime up and a post-doc of he is

looking at the control of block
a poem is in thin films and

we found that specifically
functionalize gold nanoparticles

really aligned at the interface
between the die block a poem is and

allowed us to control the orientation of
those dog but cupola as in thin films and

so our idea was pretty simple
can we use the sign tile of gold

nanoparticles and turn these onions
into these Lamell of footballs.

To cut a long story short it works
we get not only our lips oids but

we also get this Lamell orientation of the
die block PALMER The problem is that not

everyone wants to work with gold and
it gets pretty darn expensive but

this did showed that not only
could we get the ellipsoid but

it was really about this
interface between the surrounding

solution and the two Diable Coppola MS
because you can see that the golden in

a particle's all at the surface
at this interface so

that told us that we only need a small
amount of material to turn it from

being a sphere into an ellipsoid and
so traditional So

fact and don't work this was
an absolute disaster until Daniel and

Cynthia asked the simple question well
it's probably because we're using once

a fact that we should use a mixture of so
fact it's one that locks polystyrene and

one that locks Poly to volatile
period in the mines in polymer

if we do that maybe we will get
this preferential interactions and

again we stop with the c tab

commercially available we get
on humans if we make a very

small structural modification so

we have a hydroxy group at the end
of now I die Ethel version of C.

tab we still get onions but
we get the opposite.

So in this Anya we have polystyrene as
the external layer in this case we have

poly too volatile period in the external
layer so think of this as white and

think of this as black hopefully by
using a mixture of the suspect and

we can get some color of
gray in which we don't have.

We have these ellipsoids And
there's actually exactly what Cynthia and

Daniel did we start with onions somewhere
around about fifty percent we get

these really funny odd structures and
then between about seventy and

eighty five percent we get footballs and
we only get footballs

and they were thrilled and I was actually
even more thrilled since it actually

worked out that when we go even
higher we get back to onions so

this logical argument that I've told
you before that a version of grey.

Is exactly what we want and we get that
grey by mixing two relatively simple so

fact insta get that we can do this with
a variety of different molecular whites so

we can choose the thickness of these.

The next and final thing that
we needed to do was to swell and

contract the spacing so that we could
start to choose the Bragg reflection and

this is where a good friend of will
burn came in handy because burnout

again brought very simple chemistry to
this which solve this problem and so

this is the problem that we
have these ellipsoid particles

that composed of polystyrene and
Poly to volatile period thing

if we swell these in acid they
fall apart because the poly Tuvan

appear again is predicated it becomes
water soluble and so these water and

saw uble ellipsoids that we spent so
much time making full of pot and

give us the individual polystyrene
this that made up this for

so we've just disassembled the whole
structure so this was not good but

the solution is really quite
simple what we need to do

is to cross-link Cavalli cross-link
the poly Tuvan appear again

to stop this total
destruction of the particle

the cross-linking chemistry is very easy
we borrowed it from Karen willies group

you simply expose these ellipsoid
particles to a viper one for

dive Bromo butane it outta
lights the volatile period

in units we can control the level of.

Aggregation and cross-linking to
control the chemistry and now we have.

As you can see in this example ninety five
percent of the vinyl period in units free

that are available for proto nation and
hopefully by proto ending that and

the fact that we've now cross-link
these to make a hydrogen

will be out a swale and D.

swell these and these are my last
few slides this is what we get from

twenty five percent cross-linking you can
see that we start to change shape and

then if we go down in cross-linking
level to five mile percent

now we have a much better ellipsoid
shape we take these materials

we add acid and
we swell the Poly to volatile purity and

law is but because across linked
they don't fall apart and so

what you're seeing here all those
poly starring disks that I showed you

before that it's now just
like an accordion nice way O.

and contract swell and
contract by simply predicating the vinyl

period anes or
the proto naming the Vaio vinyl perience

we can go from ellipsoid to
very elongated ellipsoid and

back by simply controlling the ph out
Plimer area work does show that you can

control the brag this is about
as basic as you can do and

compared to the cuttlefish I hope you
appreciate that if we relied on this for

Kemah Flash movie did in
about thirty seconds but

it does show you that we can take a lot of
the inspiration from marine organisms and

translate that into
synthetic systems the key

is efficient and orthogonal chemistry and

hopefully I've demonstrated to you
today how we can use simple chemistry

to really affect the physical properties
of a water variety of synthetic systems

I like to acknowledge whole host
of people who supported this work

the National Science Foundation through
our materials research lab down and

mystic bitchy chemical was also a big
supporters and contributors to this

research I took to our talk a lot about
collaboration and really driven by

Kramer and Glen Frederickson who
Dan Morse to Koos and Knight And

finally I'd like to think Miller pour
sigma one more time and all of you for

your attention the soft and thank you.

So let me repeat in
paraphrase the question

I made the point of the fact that we
had the same starting material so

we could have the right same number
of an eye on a groups that was so

that we could really understand the system
so we when we went from you know

twenty to thirty to be forty we really
knew what we were doing if you don't

critically balance you get
materials that have properties that

are slightly less than the ones
that have the correct matching.

And so you can think of is as almost
a bell shaped if you too far off

you start not forming the CO S.

of eight or and an extreme examples
you get a precipitate And so

it's important to balance it but it
doesn't have to be balance perfectly and

that's what also allowed us to
have cod go in there and so

these co estimates do have a significant
amount of leeway you can't push it too far

but you don't have to have perfect balance
we just like this system because it really

allowed us to compare apples with
apples rather than apples with oranges.

So again let me repeat and
paraphrase the question

when we made the micro particles
using Michael fluidics And

again you know using some
cargo How did we stop.

And clogging of the market
fluidic channels and

so you might have noticed they would.

Fourth five things coming into
the mixing chamber there was

some water the cut on
it polymer the palm and

then some silicon fluid and
so we were forming the.

Droplets surrounded by silicon fluid and
so

by having that done correctly you
can get individual droplets and

then by having the residence time being
approximately a minute you gave time for

those droplets to solidify.

Fully cross-link So when they came out
the end they didn't Glaum up together and

also by having the individual
droplets He also stopped.

Cross-linking in the channels
when we didn't do it correctly so

that instead of individual droplets we
might have had a little bit more you know

tool three droplets connect together that
clogged very rapidly because then it just

formed this mass and that mass wouldn't
go through the mixing channel mode so

I didn't point this out but
you use your silicon fluid to actually

isolate the individual who is droplets so
all of the assembly.

In that droplets and
that droplet can travel through.

Charge complementarity is yours yes.

Yes.

Thermally.

Rapidly is that.

Why you range.

Things together because it.

Is able to relax.

You know that's the way the less was
that I know I saw again the question and

what was.

You know how do we get this long range
order and is that the fact that these

groups you know reach
a thermodynamic minimum easily is

that what gives us the long range order
naively as a synthetic chemist and

add in Glyn would probably
argue with me but

I that's the way that I think of
it that it's enough freedom for

all of these Chinas to find the time and
then at minimum and

space each other because they
want to get all these Co S.

about domains want to get
away from each other and

so it gives it enough time to actually.

Achieve the long run short and my and also
if you notice it at thirty five thousand

molecular Whitehall you think like it
didn't really get long range order and

we think that may be due to the fact
that now we have enough spacing so

that the domains are not
influencing each other

as they do when there's a shorter
polyethylene glycol or it might be.

Changed.

But the dynamics of that system.

So.

You can see one in which.

The So So
the comment was do you get exchange.

All of so if we do a thought
experiment I make my hide to Joe

with normal catatonic try block and
ionic trouble then add

a solution of a fluorescent Lee
labeled catatonic try block and

let it cool a bright
will I see the migration

of that catatonic try block into
the system the answer is yes but

it happens incredibly slowly and
that right of exchange is dictated

by the number of groups in
the little in the mines and so

if you have short enough ones the exchange
is somewhat rapid as you get to say D.P.

thirty forty this almost
becomes glacial time frames and

so you do get exchanged but

I like to think of it as as Velcro if
my velcro strip is long enough it's

really high to pull it all off that wants
but if it's short enough you can do it.

Later.

What.

You're.

So the.

Question was when we looked
at the cargo release.

You saw almost a bush just release and

then a much slower release we're not
sure exactly what's going on there

we think there may be some
cargo that is more on this

on the interface all of
the quests evade the mines and

some that are more interior
to the domains I'm not so

sure I'm a big believer in that because
these a very small done mines and so.

It.

Yeah and so
from a from a dragon release viewpoint.

I don't think these at the present
point in time have the right

release characteristics to be
of any great potential use.

It's.

All.

Right.

So.

QUESTION Was We can think of a lot
of really interesting other sofa

same beliefs strategies braced on both
the catacombs as well as a on in groups we

haven't done much work in the area but
Rohan has done an enormous amount of

work in this area and you know if
you look at some of his work you

know you can exchange a lot of interesting
things into these type of systems.

Now.

It's just.

A little more that happened Bill.

Like you this beautiful
blue crystal thing.

Thank you everyone.