Welcome. Thank you for joining us today
for the special
virtual Electrical and Computer
Engineering Lunch and Learn.
My name is Megan Orr and
I am the event director for the College of Science and
Engineering.
Before we get started,
I will share a few
housekeeping items with you.
There we go.
If you prefer to listen to
today's webinar by phone,
you can call
using the instructions on the screen
and for accessibility purposes,
I will read those numbers to you right now.
The phone number that you would want to
call to listen is
253-215-8782
and when prompted you should
enter the
webinar id which is 943 0059  8469
and we welcome you to submit your
questions along the way for
either Professor Victora
or Professor Stadler.
Each of them
will field those questions from the Q&A
at the end of their presentations and
again all questions need to go through
the Q&A feature which is located at the
bottom of your screen.
You're welcome to continue to chat with
each other.
Also, please use the chat if you have any
technical questions.
My colleague Joelle
will answer those for you and try to
assist, but
if your question ends up in the chat we
might not see it.
So please do enter that
in the Q&A
and we are also recording today's
webinar
and we will send that to you via email
after this event
and now without further ado,
I would like
to
introduce our first presenter.
Our head and professor,
Randall Victora.
Randy has served as head of the
Department of Electrical and Computer
Engineering since 2015.
He received B.S. degrees from MIT in 1980
and a Ph.D. from UC-Berkeley in 1985.
He then joined Kodak research
laboratories,
where he worked until
joining the University of Minnesota
in 1998.
Victora's research interest
is theory and simulation of magnetic
materials
primarily directed towards spin torque
RAM,
a potential replacement for DRAM
microwave interactions with
magnetic materials
and magnetic recording hard disk drives.
He is best known for his work
on recording media for which he has
received several awards
including the achievement award of the
institute of electrical
and electronics engineers magnetic
society.
He served as president of the IEEE
Magnetic
Society and is general chair of the 50th
conference on magnetism
and magnetic materials.
Professor Victora
is a fellow of the American Physical
Society and of the IEEE.
Professor Victora, I am going to mute
myself and let you take it from here.
Thank you very much.
I will share my screen now
and I hope you can all see it.
Okay well,
welcome to our Lunch and Learn.
It's good to see that there are so many
of you here.
My recollection is actually a better
attendance than
when we have it
in person, so it's a very good thing.
Randy, sorry to interject
but we actually can't
see your screen yet.
One moment to give that a shot.
So it's showing up on mine as correctly.
I wonder if you un-shared your screen
first.
Did you?
Let's take a moment,
we're still not
seeing that randy but
while you click that share screen button
again,
why don't our attendees feel free to
talk amongst yourselves for a moment
again in that chat
and if you didn't have the
opportunity to share where you're
logging
in from that would be great.
I'm going to click share screen again
and again I'm seeing
work this time?
Yes, we see it.
Wonderful.
I always thought electronics was
deterministic but I guess not.
Okay and now let me
enlarge it a little here.
Well again,
welcome.
Glad to see so many people here.
Whenever I talk to people about
what's been going on in the department
lately,
a lot of what they ask is how are you
reacting to
the COVID-19 pandemic and
also what's next?
That's actually
going to be the first thing I'm going to
talk about
as you undoubtedly read about in the
newspapers and such
we closed down in about the middle of
March and we immediately had to
move everything online and so
that included the big lectures where the
evidence is starting to show that
actually the students like the big
lectures done remotely
and as well as the labs,
which probably is not as much a success
because of course in the labs they want
to have the personal experience.
Nonetheless, we have did
successfully
complete the term.
Another problem was in the research
area.
Of course about half of the people in
the
department actually do their research
computationally or theoretically
and they could really do that work
almost as well from home as they could
do it from work,
from the actual building.
That was fine.
However, another half of them including
professor Stadler who you'll be hearing
from today,
she does experimental work and
that meant that their laboratories were
closed they couldn't get in the building.
Fortunately, the University of Minnesota
responded fairly quickly to this
and brought in a sunrise process
beginning in early June and
by the end of the month of June,
we had
almost all of our experimental graduate
students and staff as well as some of
the professors
back in the building in a very
controlled way,
such as for example,
they're only allowed to have one person
in a room unless it's a very large room,
but it's been pretty successful and a
lot of our
experimental effort, probably all of it,
is back in force.
Now of course the big question is
what happens in the fall.
For that, I actually have a slide
prepared
and I'm going to talk first of all about
the teaching when we move into this
fall semester
and I should mention here
of course that
this is changing continuously as
the administration responds to what is
going on at other universities
as well as what might go on here.
But our plans at the moment are to teach the
courses
in an assortment of modes.
This is pretty
much what
President Gabel has prescribed so our
large classes are automatically taught
online by Zoom.
There's a couple of reasons for this.
First of all, as I mentioned from the
spring,
students seem to like it okay and second of all
and find it effective.
After all, if you're sitting
in a big lecture hall,
maybe listening to it on Zoom is really
no different or even better
and the other thing is because they're
doing social distancing,
and they're basically expanding
everything by about a factor of four or
five.
A big class, if you have 100 people in a
class you need a room for 500 people to
put it in
and there's just not enough room for
that. So that's why the large classes
defined as 30 or more students,
well those are all going to be
online.
Most of our labs are currently
planned to be taught in person
and this is because again the students
thought that they learned more
in person and there was room for us to
be able to do it fortunately most of our
labs were already
socially distanced inside because
there's lots of equipment filling up,
lots of space.
That's our attempt here
to try to
teach those labs in person
and then for the smaller classes, well
some of them are both in person and
remote,
others will only be remote.
We're
particularly fortunate in the ECE
department
to have most of our classes carried on
UNITE.
UNITE is the way we broadcast classes to
industry
in normal years and so you have a
cameraman
and multiple cameras in a room,
as well as multiple microphones
and they record everything
and so that
way you can successfully
teach both in person and have a good
remote presence.
That's the plans for teaching.
As I mentioned before,
in the research area
graduate students and other staff who
perform experiments,
they already regained access to
laboratories several months ago.
Unless you have a very large lab,
of which you have only a few in this
building,
only one worker is allowed in the room
at a time and they're supposed to be
keeping schedules
that allows them to coordinate so that
you only have one person in a room at a
time.
So far I believe that's working pretty
well.
Our computational people continue to
work remotely
I'd like to mention that the centralized
facilities such as the Minnesota Nano
Center
and the Charfac,
which is where you can characterize
materials and such, are also open.
They open concurrently with the
department.
So we think we have this under
reasonable control.
Last few minutes,
I'd just like to
mention a couple of projects that are going
on in the department
that you may find
interesting.
One project that has gotten some
attention lately is an effort to improve
clean energy.
As you can see in the picture,
there's some solar cells and no we are not
making solar cells these days,
that's pretty much a commodity business.
But, we are working on trying to make
better converters.
One of the problems with solar cells
is they might produce
the electricity at a particular voltage
with no particular phase attached to it
and you actually want for integration of
the power grid,
something much different
and so you have to do conversion and
because you know solar energy has become
much more of a commodity,
a lot of it is about price.
So Ned and
his students
came up with an integrated magnetics
converter that
we believe offers a lower system cost.
If you want to read more about this,
you can check out first at first glance,
you
can look at our website
which explains some of the details
behind it and also you can find the
papers or references to the papers
there that'll let you know more detail
if you're really into this subject.
This being the time of COVID-19,
we of course have some work going in this area.
I'm going to talk a little briefly about
a diagnostic device that
is originated by Professor Wong and his
collaborators,
including some people in the veterinary
school and what you see in this picture
are two different things.
On the left-hand side,
you have the actual
place where the saliva or blood or
whatever you're going to use
goes in and then you have a cell phone
to do the communication so this is
try to make this cheaper.
If you think about any of these
diagnostic devices including the ones
for cancer, etc,
everything is about sensitivity and so
one way to make things more sensitive
is to have, one approach to making it
more sensitive
is to basically
imagine that, for example, the little
virus cells,
the little piece of virus can be
chemically attached
to a magnetic nanoparticle which can
then be
detected very sensitively using the
device
that's shown in green here is actually a
based on a  sensor
and then it feeds the information to the
cell phone.
The idea here is that you might have
something that can give you rapid
results,
but also be so inexpensive
because most people already own cell
phones,
that you can rapidly make use of them
without a whole lot of cost.
Okay with this, I am probably finished
with my part of the talk which is meant
to be quite short
and I take any questions you might have.
Be sure and use the question and answer
feature
on your screen and then after a few
minutes, I'll introduce Professor Stadler.
So far no questions
yet
I think there will be more online/distance courses
offered.
I mean I guess
there's two ways of answering that.
Our department was substantially
online already
in the sense that most courses that
were
interest to people for example in
industry were already broadcast through
UNITE.
The total number of courses that we
offer will not be any different than we
would in a normal
semester,
it's just that in this case
every single one of them will be
available
online aside from some of the lab
courses perhaps.
It looks like there's one more question
here about whether or not
alumni have free access to UNITE webinar
seminars
and webcasts.
Yeah so
that is really more of a UNITE question
than mine.
Yeah I'm going to give you a big "I
don't know",
I'm sorry
and are there any safety issues when
only one person at a time
is in the lab?
Yeah this is a very good
question which I actually
recall that you were addressing for a
little bit here,
do you want to talk to this?
You're muted at the moment yeah.
I actually was in the building monitoring
things like
equipment to make sure we didn't have to
shut everything down all the way
and just kind of the facilities
people don't always go into the chases,
make sure we didn't have any floods.
Basically, there weren't any students
here I actually I would see
an occasional facilities person
a week, for a couple months.
The students are in
back in the labs and there's a lot, for
example, we have a google sheet
and my group fills in what lab they're
going to use at each time.
Every person who is approved to return
on sunrise
was given two masks by the University
that are reusable so you take them home
and wash them if you don't have your own.
I think most people have found their own
and people seem to have found ones that
are comfortable and so they're buying
those,
but the university supplies two masks
everyone who's approved to come in and
would supply more if they were asked for
I believe.
Also every room that has had permission
for sunrise
person to come back has special cleaning
agents
and so the idea is you would clean up
your area if you know someone is coming
in right behind you.
Everyone has been using those
regularly to my knowledge, you have to
have a card, a U card, to get into the
building
everyone has the keys to get into their
space.
As of now,
I think it's a very safe work
environment for graduate students who
are back,
I don't know if many undergrad
researchers will be coming
into labs because we do need to
keep distanced and make sure
that we can get through this part of
it but so far
I believe everything is pretty safe,
To more directly answer the question
for a lot of labs,
it's as safe as it
ever was
because a lot of labs only had
one person in them to begin with anyway.
That's not a great answer,
but I think
that's pretty much the situation.
There's a couple other questions here
which is how has undergraduate
enrollment changed if any
and here the answer is that at the
moment, it's looking pretty good within
the ECE,
actually within the whole College of
Science and Engineering.
The latest numbers I saw as we were
actually up one percent
relative to last year,
we do expect we're
going to lose a few students
as time gets closer and
people evaluate whether or not they want
to be taking as many
so many courses remotely or not but so
far,
within the college I don't think
it's much of a problem.
With the University as a whole, I'm not
as sure.
Actually could I put in one piece of
information there as well,
our freshman introductory class 1301,
which is a kind of internet of things
class,
had not a lot of enrollment for a
while I think as freshmen were deciding
what to do
and now with it being online,
with some
in-person labs we have a record number
taking that so
it's a good recruiting class for ECE.
I noticed that too, I was very
happy about that
and then the other next question is at
what stage of the coronavirus
infection, early to late,
is the device
capable of detecting the virus?
My answer to that is that
the claim is that it's able to detect
some cancer, so basically the same device
is also being used for detecting cancer
cells.
I think that cancer cells are much
rarer in the bloodstream
than COVID-19 is in saliva or
other materials and so
it's probably
that it is probably the
answer is it's very very sensitive on
COVID-19 scales.
I noticed, by the way, the University of
Illinois is also
looking into some kind of saliva based
test.
I doubt it's working on the same
principle but i've noticed
recent publicity on this.
I think that's it.
Now, let me introduce Professor Stadler,
who is your main attraction today.
Professor Stadler has served as
associate head of the Department of
Electrical and Computer Engineering
since 2018.
She received bachelor's degree from Case
Western University in 1980
and a PhD from Massachusetts Institute
of Technology
in 1994.
She was then a national
research council post-doctoral fellow
at the air force research laboratory at
Hanscom Air Force Base until joining the
University of Minnesota.
Her research is in magneto optical
materials and devices
and magnetic nanowires, the topic of
today's talk.
In optics, she's working to commercialize
a new silicon integrated garnet for
optical isolators.
She has taught at the IEEE magnetic
society summer school
in both Chennai, India and Sicily, Italy
and she's also hosted the school here at
the University of Minnesota in 2015.
This, by the way, attracts roughly 100
graduate students from around the world
wherever the school is held.
She's also
served as a distinguished lecturer for
the IEEE magnetic society,
which is considered to be a substantial
honor
and will be a general co-chair of the
intermeg conference in 2023
and by japan which is expecting to have
something like 1,500
attendees.
Professor Stadler was
the general co-chair of the MRS meeting
in 2004
and she is a fellow of the MRS as well.
Where MRS is materials research society.
Professor Stadler?
The classic issue I want to make sure
that I
unmute and now I will share the screen
which will
mean others need to stop sharing but
Okay let's try this one.
I'm good, all right.
For attending the talk, I see a question
about agglomeration and I'm not sure if
that was for
Jian-Ping Wang's device or the wires we
talked about here
but let me just address these since
I'm not sure of the answer for Jian-Ping,
although I know we all do
a lot of work to make sure that our
particles don't agglomerate.
That was one of the big issues when this
field got started.
That aside,  the topic of today I
was asked to speak on nanohealth
using magnetism
and it's because we have these magnetic
nanowires that cells seem to like
They often taste them,
they end up inside the cell,
when cells divide the daughter cells
both end up having nanowires
and so I'm going to show you how the
cell population will distribute our
nanowires.
So the question for agglomeration comes
into this because
if the particles all settled on the
cells together,
and then you just have one big
particle the cell tried to eat,
well the cell would literally die trying
but instead we have particles that the
cells disperse
for us which is pretty interesting.
The backdrop drop of this picture
actually
is the actual microscopy of the cells
with the nucleus stained blue
and so I'll get into that
as this talk gets going.
So I was sort of in a fun mood I guess when I
put together the abstract and I
introduced this
topic see if I can
get my slides to forward, there.
I sort of put the nanowires down as
scrappy fighters and I'll tell you
why in a minute.
So first off, we have in this corner
cancer cells weighing in as the
representation of your health.
This could really be any cell it could
be a coronavirus as
Jian-Ping Wang's technology is further
developed and he's able to take
as Randy mentioned,
technologies that were
meant to detect cancer cells and detect
really any
bio-material,
especially cells but I'm
going to use
the cancer cell to weigh in on on behalf
of all
illnesses and then our champion is going
to be
Minnesota's magnetic nanobots.
You might have a hard time seeing him.
He's kind of small and that's why i say
he's a scrappy fighter.
Kind of reminds me of
some long lean fighter
stepping into the ring against some big
heavy hitter but it turns out,
if you want to picture this,
picture a
one inch piece of hair or maybe a four
inch piece of hair
and shrink it a million times.
That's the size of these nanowires
and if you zoom in on them,
you can see that they represent, if we want them to,
they represent barcodes.
We can grow
different materials along the length of
the nanowires or maybe we'll make them
all one depending on the design that we
need these nanowires to have.
Let's see how it's going to do in the
fight,
which is actually to label detect and
kill cancer.
We have a little side benefit here or
a sideshow if you will
that it turns out these wires as we're
in the middle of determining
can we label, detect, and kill cancer,
we found out that our nanowires may also
be able to save organs.
This is
seems like a very different feel,
but I think
towards the end of the talk ,
as I describe how we reach this
application,
I hope you find it
interesting and our nano-wire has a lot
more
to him than initially appears.
All right so cancer.
What is the first
step in fighting cancer?
Especially if we want to
personalize the medicine?
Well what we'd like to do,
is find its molecular calling card
and this could be by finding it in the
body,
perhaps we have a blood or tissue biopsy.
Blood biopsies are
a lot safer and less invasive.
Those of us that donate to the red
cross are
kind of used to having a blood biopsy
regularly.
So it's something that is a
lot less invasive than having a piece of
tissue
taken out of your body.
How do we find
this calling card
and what is the calling card?
Well the
calling card is this thing called
an exosome.
Let me explain to you
where it comes from.
If I have any cell and I've got the blue
nucleus like we had in that image,
on the first slide,
just because
nuclei are often stained blue,
actually maybe what I'll do is put a
pointer here.
Can you see that?
This is the nucleus.
Now it turns out that a lot of cells
like to sample their environment.
So they figure out where they are
and they determine whether they're happy
there, what's around,
and communicate with each other even by
sampling,
literally sort of taking a little nibble
of their environment so
this is done by the membrane enclosing
around
a bit of environment and then when this
this process is complete,
this membrane closes off on itself
and you end up with basically a bubble
of the of the environment that's inside
the cell
and then while this vesicle now, we'll
call the bubble,
is traveling through the cell,
the cell processes
the little bit that it's seeing of the
environment and it also
tends to have this bubble in the
environment, curiously enough,
actually tastes of the cell.
You could end up with
bubbles of the cell that are inside this
bubble
which is actually the outside of the
cell,
so
it's almost like a bullseye effect and
these little
bubbles inside the the bigger bubble,
these are called exosomes.
This vesicle is called an endosome,
the cell processes its information
it exchanges information,
makes these exosomes by enclosing around little bits
of the inside of the cell,
and when this main vesicle hits the wall
again,
it spits out the exosomes into the environment
and so these little exosomes contain
information about the cell.
RNA, some
molecules,
little things that when you
find these exosomes,
you can tell what
cell
that exosome came from.
There's a lot of studies that
Jaime Modiano and some of his
collaborators have been
doing.
He's in veterinary medicine
I'll talk more about him soon.
They feel as though these exosomes
travel through the body, which
is what I'm showing here.
Let's say there's a tumor somewhere in
your body
and these exosomes travel through the
bloodstream and they tend to settle
in an environment like the lungs and
that environment becomes friendly to a
tumor cell
so we used to think a circulating tumor
cell was one of the first things you
could find
to predict or diagnose cancer,
now we are feeling as though these
exosomes are actually preparing an
environment for the
circulating tumor cell to metastasize
and so if we can find the exosomes, it's
an even earlier indication.
Let's see if we can collect those
exosomes and that's where the nanobots
come in or
nanowires depending.
Some people I think picture
like asbestos or something they hear
nanowires, but these are
a lot smaller and functionalized to be
friendly to the environment which
I'll show you some data of that
later.
We sometimes call them nanobots
to explain them well.
What we're going to do is engineer
these nanobots to label
the cancer and that usually means you
put some kind of functionalization on it.
In our case, we'll use a peptide that's
called RGB.
Sometimes we'll use antibodies
and there are just
pretty easy chemical ways to coat the
surfaces of nanoparticles
with these polymers that become specific
labels for what you're looking for
and that's part of the answer to
that previous question about
agglomeration.
These coatings on the particles keep
them from agglomerating
because they don't see each other's
dipole fields.
All right next we're going to
magnetically collect the exosomes
this might be um as i'll show you later,
by putting the wires in cells and
letting the exosomes generate from the
cells and we can collect them
magnetically
because they're attached to the
nanowires or we might be dealing
soon with a blood biopsy from a
collaborator
that I met down at the Mayo clinic
during an exosome workshop.
We could label the nanowires like this
and put them in the blood,
where there are a lot of exosomes from
all kinds of cells.
Now cancer tends to eject
10 times as many exosomes as other cells,
but still there's a lot of other cells
in the body.
You still have to pick
out
those few that are from cancer
and that's what he would like us to help
him do as soon as we're able to
collaborate a little more easily.
Which was put on hold because of
COVID.
Then, what if we then collect these
exosomes and we alter them
for personalized medicine because the
outside of the exosome is recognized as
something coming from the body and
actually coming from the tumor it goes
ahead and settles in the lung or
wherever the tumor is about to
metastasize
but we now have altered the inside of
exosomes so we can
deliver a little personal gift to the
tumor.
I'll say more on that later and now we'd
also like to use magnetic identification
to determine if the exosomes we find
later or find metastasize somewhere are
they from the cancer?
Are they the wire we label cancer
exosomes with?
For that, we're going to use
something like RFID.
This is where Rhonda Franklin comes
in as my collaborator.
She's in our Department of Electrical and
Computer Engineering
and she works on high frequency circuits
and materials.
If you picture the normal radio
frequency identification
is your RFID tag,
you know these are
everywhere.
I maybe don't have to talk a lot about
these,
you can picture them
sometimes when you set off the
alarm when you're leaving a store,
lots of different places we see these.
We're actually going to use
something we're calling
FMR-ID.
Magnetic particles oscillate in
response to a specific frequency field
combination.
We can capture that signature and
know what material we're imaging
just by having being able to look for
an absorption peak
as a field is swept at a certain
frequency or as the frequency is swept
at a certain field and then we can say
oh wait that's ours, so we know that's
from the cancer.
All right.
I won't say a lot more on that
process,
now back to what we do with Jaime and I
put here an alumni from ECE
who may even
be on this call.
He has given me this picture because
it's an alumni from Electrical and
Computer Engineering that I met at an
open house that we hosted
maybe a decade ago and he introduced me
to Jaime Modiano because
he breeds these adorable puppies and his
kennel club gives funding to Jaime
Modiano to study cancer,
specifically bone cancer,
from this breed.
If we learn how to help out this breed,
we also learn how to help out humans
because we have very similar biological
triggers for cancer
as our canine companions.
The interesting thing is when I met
Jaime who Dave introduced me to,
I was already working with some of his
cells with
Alice and Hubel.
She is a professor
in Mechanical Engineering
and Jaime had given her cells to cryo
preserve
Allison has actually a small business
and a center specifically for cryo
preservation of biomaterials
and so we had talked with her and asked
is there a way that we could label
cells that she'd preserve, warm them up,
and label them with nanowires
and we wanted to see if we could control
the cells using nanowires.
As a first step,
maybe some of you have seen this before,
we just have a movie of nanowires
moving as we're
moving this magnetic field
back and forth.
Unfortunately, the clicker
to get the movie going is different than
the pointer,
so we move this magnet back and forth
and we see the
the wires move, they are way too small
to image by
optical microscopy, but we label them
when we want to see them.
We can label
them with gold for example,
and when they hit the right spot in the
light,
they emit surface plasmons
so they look bigger than they are and we
can see them move,
especially when we're
applying a magnetic field so we know
they're moving because of what we're
doing.
That's something we worked on a while
ago and this
is something a little newer,
but not so new.
Which is looking down on a petri dish
where cells are adherent to the bottom
of the petri dish
and we have dropped our nanowires onto
the cells
and you can see what you might call
agglomeration there's kind of blobs of
nanowires.
What I'm going to show you is a
movie of
how the cell,
just like this,
a cell comes
along
and it attaches to the nano-wire.
This thing we've stuck on the
nano-wire is
is that peptide called RGD.
Your extracellular matrix
is made up of fibers that have RDD on
them.
The cell thinks this is extracellular
matrix
and the binder that's cancer cells
way overexpress the binder for RGD, so
very preferentially,
the cancer cell
attaches to our nano-wire,
thinking it's attaching to the
extracellular matrix,
maybe about to
find a good site to metastasize and
instead when it grabs the nano-wire and
it starts to
cells normally walk around and they lift
up off the substrate and divide and go
back down on the substrate,
all the time they're moving around,
instead of sticking to the extracellular
matrix, they actually walk away with a
nano-wire.
That's what I'm going to show you for
this next movie it's handy to explain it
before
showing it to you.
In particular,
if you watch these clumps,
you can see that they are breaking up
This one in particular breaks completely
and a lot of these others just divide
they're going to take their time and
getting smaller,
but after several hours, all of these
clumps have dispersed within the cells
and you can see actually when they round
and they pop up off the substrate like
this right here and that one right there,
that's where the cell comes up off the
substrate divides and goes back down
because cancer is always proliferating
much more than normal cells,
which is one of the problems.
In this process, we actually end up
with all of the cells
labeled with nanowires inside of them,
so here's that blob I
mentioned you could look at
and you can see over the course of just a couple
hours,
it's completely dispersed as the cells
grab onto what they think is matrix and walk away
carrying just a nano-wire.
So you might say to yourself at this
point,
okay now you have cells
that have nanowires inside of them that
doesn't sound like they'd be happy
but actually as I'm about to show you,
we
find
they don't die,
for one it's normal for
cells over 24 hours or so to
to have a few cells die and the question
is do more cells
generate than the cells that are dying?
But this is a normal medical material, this
nanosilica and you can see there's a
certain number of cells that die but
meanwhile there's new cells being
generated.
In our nanowires,
it turns out very much fewer
cells die at the similar concentration
which are these two
and when these nanowires are coated with
RGD,
actually it's in the noise.
Very few if any cells
die by the end of 24 hours which is
what we were watching them for.
They don't tend to die and now it
turns out they're also
happy.
This is a measure of metabolic
activity.
These cells are kind of taking in the
nanowires.
It is true that if they're bare
nanowires,
the more we put in this is 25
to 200
nanowires per cell,
the cells
are less happy,
they're not as
metabolically active
as without having nanowires at
all
and if we coat them with something inert
like PEG,
well it doesn't really matter how many
we put in there's an initial drop in
metabolic activity,
but then that's about it because they
don't really notice a nano-wire coated
with PEGs.
But, if we code it with our peptide RGD,
here you can see that the cells are
actually returning to normal metabolic
activity.
This is kind of my
joke about the cells are active they're
normally metabolic as they would be
otherwise.
That was a nice find for us and we
have a lot of images of how they show up
in the vesicles
and what I want you to remember is if
they're inside a vesicle,
and the vesicle is uptaking exosomes as
it travels through the cell and then
those exosomes get spit out
and we collect those exosomes as our as
our most recent question
and it turns out we can very easily
collect those calling cards which are
exosomes.
At first, we just had the cells on the
bottom of,
they like to be on the bottom of a petri
dish so that's why they're down there
and for weeks we could just put a magnet
here every day
and collect more exosomes so by putting
nanowires on top of the cells,
the cells uptake the nanowires and then
every day for at least
several weeks as the cells do their
normal uptake and spitting out of
exosomes,
we could collect them every day.
It turns out we noticed at first we
thought,
maybe the cells break up the nanowires and these
nanowires end up inside the exosomes.
There's a variety of reasons why
that's less likely to happen than what
we have several pictures of now,
which is exosomes collected
on the nanowires.
They just stick to
the nanowires and the nanowires when
they are ejected by the cell have a lot
of exosomes hanging on them
and when we collect magnetically
the nanowires,
we get a lot of exosomes and
that's what this image is.
Our new collaborator that we've
been talking with in
epidemiology he said he would like to
see if we could collect the cancer
exosomes from blood samples he has
and then exchange the inside of the
exosomes and if we
then have really personalized medicine
inject these
exosomes back into the
the original source which of course at
first will be something,
maybe a rat instead of a dog or
a person at first but
just see could you get these exosomes
with a little gift, inside a little toxin
to land where a normal exosome would
land so you stop the metastasis before
it happens.
Now I don't know if anyone on the call speaks German.
But when I took about 20 freshmen
over to Berlin and we went to
the basically the NSF of Berlin,
of Germany and they were trying to give
a pitch to our students to apply for
fellowships where the german government
would pay our students to come to 
research
in Germany.
I made the mistake,
the next day I went to bring a gift
to the person who had given us the
presentation
and I thankfully had my daughter who's a
German speaker with me
and I said to the guard at the building
I have a
gift and he didn't understand me so I
said a das gift
turns out das gift means poison in
German.
Literally we are going to deliver it
das gift to the tumors
but I did not deliver das gift to
to the NSF of Germany, I actually had a
gift.
So now we know we have wires and cells.
Can we kill the cells?
We know that we
don't kill the cells
until we want to kill the cells and
that's important just for cytotoxicity.
But if we want to kill the cells,
we have a couple different mechanisms to do that.
One is I'm going to show you if you
remember from your lab days
when you had to take chemistry or maybe
electrochemistry,
this is a stir plate from the side,
this little button here controls a magnet
under this plate that's going to go
around
and these are three cuvettes.
The two
outer ones have nanowires in them and
the inner
the center one doesn't and what you
notice is if we have a laser it's
actually off here and it's firing its
light through these cuvettes,
but that laser light is going to get
scattered where there's nanowires.
This cuvette and that cuvette you can
see
the scattering because there's nanowires
inside them.
The center cuvette doesn't
have nanowires in it,
we just have it
there as a control
and so what I'll do is play this movie
where we rotate the nanowires just to
show we can do it.
If I can get my
pointer off and my
oh maybe it's gonna go.
Sorry I have to switch to the
arrow before it lets me do that.
You can see the nanowires are
rotating because
the laser light is blinking.
Without putting too much time into that, that's
one way we can literally scramble them
from the inside
or mess up the matrix that the tumor is
starting to settle in.
The other thing we'd like to do is use
the hysteresis loop of
the magnetic nanowires.
This loop represents hysteretic losses.
I notice Randy mentioned some work
Ned Mohan does,
Rhonda does high frequencies.
Every time
you have an oscillating
field you you have to worry about having
some hysteresis and normally hysteresis
losses
manifest themselves as heat probably
where you don't want it in an electrical
circuit,
but in our case we're going to use that
heat and actually we're going to get as
large a hysteresis area as possible
so that we can get a lot of heat by
circulating a magnetic field.
We're just
going to alternate the magnetic field
back and forth
and every time we cycle this hysteresis
loop,
we'll end up having heat generated
and if you take the product of this y
versus x moment
versus applied field,
then you will then you actually get
energy
per volume or energy per
weight.
Now if we want to look at the
spions that are used,
so that's the best area we found you'll
notice actually that it's
vertically very high,
it's got a high Ms
compared to other materials
and we can tailor the width and that's
important for a reason that i'll bring
up
in the future, but right now I just want
to show you what they're using a lot
because it's off and on FDA approved.
They have spions or super paramagnetic
iron oxide nanoparticles
and their hysteresis loop is a lot
smaller because the Ms is smaller
and it's also sheared generally and that
means
the more field you apply the more heat
you get
and we would like to see if we could
apply
a non-uniform field but get uniform
heating and I'll explain that in just a
minute here.
So this was our idea for killing
tumors
and then we talked to John Bischof who
has systems where he could heat our
wires for us,
AC magnetic fields and we he did a lot
of work killing cancer with
heat and he said one day at the Campus
Club,
there's a lot of other applications for
nanowarming
besides killing cancer and your
nanowires heat
very fast and we have another
application that I want to talk to you
about
and that's where I'm going to mention a
new center
that we just got.
John Bischof is leading with mass
general for an ERC, which is the largest
center that NSF
gives to schools,
there are very few of
them across the country
and literally like a month ago,
John Bischof just got the good news and
passed
it on the ATP Bio,
which is the name of his center
is funded and the goal of that center
is to save the organs.
Rhonda Franklin in our department is
one of the
big, big leads on it.
It's a really big deal with,
as i mentioned, mass general,
UC Riverside
and a lot of collaborators
and we're really excited to work on this
problem.
I'm giving the website the best
information right now because it is
brand new.
I found was on the institute of
Engineering and Medicine Website
and we also have on ece.umn.edu,
maybe Randy wants to say something.
Notice about this because many of us
including Rhonda is one of the big
players,
is part of the center.
So he just said it's one of the — 
 our
website it's one of the first news
stories is all about the center.
Please go to ece.umn.edu also and read
about this center.
We're really excited
about it.
What is the motivation of that center?
What is save the organs?
Well it turns out that donors,
the tissue for donations,
they're only viable for a fairly short
time a lot of organs and tissues are
only viable for four to eight hours
On my license,
if I have an accident or a sudden death
and someone can still use some organs,
I would love to know they were used by
someone but they have to travel
to someone who's sick which means that
person has to be ready to take an organ
or tissue within four to eight hours of
a rather surprise event
and that can really limit the number of
successful
transplants that are possible so if we
could
extend that viability time
to even a week,
the transit time goes way
up.
We could help a lot more people using
donors who are
quite willing to help other people and
so that's what the center is about.
It has a lot of components to it but
how do you
extend the viability of an organ?
First, the idea is to freeze the organ so this
is in this case,
just tissue this is an
artery.
This is an artery that
you can see it looks like an artery,
but it's frozen to liquid nitrogen
temperatures in a
in a cryo preservation agent which is
a fairly biocompatible
anti-freeze-like material.
The problem is
when you try to heat it,
it's pretty well
understood now how to freeze, especially
tissues,
and they're getting larger and larger
volumes that they can freeze and still
have them be
viable but how do you heat it?
Well if you heat it
non-uniformly,
you crack the sample and
then you don't have a viable organ
anymore
and if you heat it too slowly,
you
actually crystallize the antifreeze.
This is like if you've seen a lake in
Minnesota in the spring, let's bring it
back home,
and it's a dark ice, maybe
see-through ice,
but as it warms up in the spring,
it turns white.
It's very strange but
it actually crystallizes on warming
and
the way to avoid that is you have to
heat really fast
and that means that you don't give the
solution energy to crystallize before
it's already melted.
This is our example I'm just going
to show you the nanowires again,
remind you that they're very small,
this is a similar scale,
a red blood cell
compared to our nanowires.
But their heat distributes around them,
so you need a fairly low concentration
to get a fairly uniform heating
and the critical warming rate
if this is
temperature and this is time,
is shown by this dotted line and what we
found is
all of our nanowires completely beat
this critical warming rate.
If we cool down to liquid nitrogen
temperatures,
we are back to zero which is like the
temperature of ice and it's
ready to be warmed up as if it had just
come from
the refrigeration unit of
our organ harvester or
something and it's back to that
temperature within a minute
and some of our particles the initial
curve is actually a thousand degrees a
minute,
but this critical warming rate is about
100 degrees a minute for the
solution that we have our tissues and
organs in.
That's why John asked if we'd be part
of this ERC and we're really happy that
it's funded
and we have a new application for
nanowires
and then the other thing because I said
I'd mention it,
let me just show you
quickly
that if you have coils and these are
switching back and forth so your
magnetic field is switching back and
forth,
which means you can cycle that
hysteresis loop.
You often find that the field isn't
uniform
so they have a volume they've defined a
fairly uniform
field and they want their tissue or
organ to fit in that.
If you want to have larger and
larger organs,
then you need these coils
to be pretty big and that gets harder
and harder to be uniform
so we are able to optimize the
coercivity of our nanowires, which means
we could have uniform heating
in a non-uniform field just by making
sure their coercivity is below
like in this picture,
the yellow field.
So right now, we have this
is our paper that we've published with
John Bischof.
This is near term John Bischof has
already done arteries using spions and they got to
about 150 degrees per minute,
they need to be faster than 50
degrees per minute and I think their
best case is 150 degrees per minute
and we're able to go a lot faster so I
can't wait to give this a try.
I think this is something that we might
be able to try but of course now we run
into some biocompatibility.
A lot of things have to be studied
before we know if this is possible.
That's kind of a lot in a short time
and so i'm going to just give you some
take-home points that you might remember.
The one is just Minnesota's battling
cancer at the cellular level
and we have these magnetic nanobots.
We are collecting their calling cards
magnetically,
we're ID-ing the cancer,
using those
nanobots with the new FMR-ID and we have
a new forms of treatment understudy this
blender and heating.
But also that this heating is new for
us to study
organ restoration.
Hopefully you'll
remember those points.
I could take questions.
We are not at critical trials yet.
No, we're well some of the barriers are
actually,
the question is
if any of these magnetic methods of
killing tumors made its clinical trials
and if not what are the biggest barriers?
There are nanoparticles being used in
tumor therapy now.
I know gold nanoparticles with
plasmonics for example then you need the
light to get into those particles.
Magnetic particles are being used for
separation
clinically as well as for research,
but as I said there is
some FDR, FDA approval that kind of comes and goes.
FDA is a big part of it and also just
finding collaborators, finding the right
niche,
that this is something
that rises to the
priority for everyone involved, the
medical people and the physicists and
the electrical engineers.
Like I said,
I mentioned I
should have had a list of all the
collaborators that are interested in
this research.
Hopefully we get to clinical trials,
especially as part of this ERC.
That's definitely on the table for that.
Concerns for heating tissue
too quickly,
well the good thing is that
you have the nanowires inside
the tumor cells,
so that means you
deliver the heat specifically to the
tumor.
You can monitor that heat and stop the
magnetic field it's,
you just turn off the
power source and you don't have any
more heat.
I think that is
not so much a problem and then
as far as the organ restoration,
fast is better.
As long as you stop at zero.
There are some people who work on
nanoparticles that are made out of
materials that have their curie
temperature
at the place where they want to limit
the temperature rise
and that way the samples aren't magnetic
anymore after they get to the
temperature of interest.
That is another approach.
Thank you for informative, exciting work.
I thank you for that comment.
Yes, we can kill cells, we have
done that already in
in petri dishes.
Are there other shapes
of the wires?
There are,
in other groups other shapes
being studied,
but we are really interested in using
wires because they have
a very high anisotropy so we know the
wires are either magnetized up or down.
They don't tend to magnetize, this was a
wire the moment doesn't tend to point
this way
and that means that we can run a domain
wall up and down the nanowire and cycle
that hysteresis loop at a tailored
coercivity,
so we're not personally studying other
shapes because we think
nanowires
are the way to go.
Might be possible someday to know you
killed
all of the cells present.
I would like to think so because the nanowires are
labeled,
so if we don't have any more,
well if you can go in and collect the
cells at the
particles after they've killed the cells
they're in,
then you can
look to see are there any left?
Because there's ways to remove the nanowires
from like a rinsing if they're not
attached to a cell anymore
and they aren't attached to anything
that isn't cancer so if you still get a
magnetic signal from the site,
you probably still have a cancer
cell or two and then you need to
continue with the therapy.
How do I make the nanowires?
I was wondering if I should show that
we make them in
inside nanoporous
templates.
Those templates are like this big
and wthese templates have
holes going through them,
but the holes are so small you could
never see them.
They're only 100
nanometers, 30 nanometers wide and but
they're in this direction,
so we coat with metal here, put a polymer
on the back, and we electroplate
inside those pores and then the
nanowires take the shape of those pores,
which  are a wire shape.
We make billions of nanowires, actually we make
milligrams of nanowires at a time.
Favorite materials for the nanowires?
We are using iron or iron cobalt
is very stable in the saline type
solutions.
Iron can oxidize and then you don't
really know what the moment is,
iron oxide itself has a fairly low
moment so the height of that hysteresis
curve is
is smaller and then if you're tailoring
the coercivity, you don't have much area
for heat or for
rotation.
We really
actually want to have
long nanowires made of something with a
high moment so that we have
a hysteresis loop that has a lot of area.
I should mention that
those cells that really seemed
happy with the nanowires,
those were nickel nanowires.
Nickel is not usually thought to be
biocompatible,
but again it's the coating
that makes it critical.
So there are
covalent bonds to the coatings that
are very stable and once the wires are
coated,
the idea is never really to leave them
in the body for long.
If you deliver them,
you use them and you
take them out, and so
right we're not as worried about
needing something like iron oxide
because
maybe iron oxide is more bio-compatible
but even those are coded.
Right now, we're really going for
properties which is high moment
and high-end isotropy.
Will the nanowires degrade with time?
Could be, we have not seen that yet
in the long run you'd want to study do
they end up in the
kidneys or something which can happen to
nanowires or in the liver
but or it can happen to any nanoparticle,
but again, we don't really have
applications in mind,
where we would leave them in the body
for long and a lot of our applications
are actually just in a petri dish.
We just want to collect those
exosomes.
It would be ideal to have a
measure on them so we can see where they
go if they were re-injected,
but for studying cells and studying
exosomes they would never go
back into the body anyway.
Can ultrasound be used to detect
nanowires
and kill the cancerous cells?
I don't know. We have made
magnetostrictive materials which would
be responsive to sound.
Any mechanical wave,
so that was one
of our initial goals is
the wires would change shape
with an applied stimulus.
They change
moment with an applied mechanical
stimulus which sound could do.
Right now, it seems like the field is
a lot more powerful
on magnetic particles than sound.
Maybe someday,
we'll come back to that.
All right well,
we're just about out of time.
Thank you everyone for
all of those wonderful questions and
thank you to
Professor Victora and Professor Stadler
for
updating and sharing us on many things
going on in the department.
A lot of wonderful
research. I wanted to let you know
about
a couple of additional upcoming
opportunities these this fall.
We'll have numerous webinars.
These are
just a couple
of those that are coming up.
One is a
behind-the-scenes tour of the St.
Anthony Falls Laboratory
and that is Thursday, September 24th from
noon until 1pm central time and you can
register for that at
z.umn.edu/safl2020.
This will all be shared
with you in the follow-up email that
you'll receive
within the next week or so.
We also have our next installment of the
college's Curiosity
Drives Progress Lecture Series.
It is focused on research that is taking
place in the College
related to impacting communities and
the professors presenting in that one
are Saif Benjaafar,
Lucy Fortson and Ellad Tadmor
and that is all we have for you today,
but again this is being recorded you'll
see a follow-up email
in the next week or so and we also
welcome any feedback.
Feel free to reach out to us at any
point in time if there is
additional programming that you're
interested in seeing virtually in the
coming year.
On that note,
I will say thank you
again and we hope you have a wonderful
day.
