- Hi guys, I'm Olivia
and we are in the Microfluidics lab in Willis Annexe
and I'm here today with Bac.
Bac, do you wanna tell us about yourself
and what are you doing?
- Hi Olivia, hi everybody.
My name is Bac, I graduated from Korea
and I worked in a Japanese company
before joining Tracie's group
and my topic is about artificial kidney.
- So, why do you want to look into artificial kidney?
- Because, you know, most of the kidney failure patients
now they rely on hemodialysis
- And hemodialysis has some disadvantages.
So, hemodialysis is a method require you to come to hospital
every three or four times a week
and treatment gonna long for, like three to four hours
at times.
and that treatment is not continuous, right?
You know the kidney has filtration continuously
within, like, lets say one minute,
one liter of the blood's being filtered.
So, all the toxic substances being removed.
So, with hemodialysis, the toxic substances still remain
that's why people health getting, like decline.
So, hemodialysis keeps people alive
for like five to ten years,
so we want to improve that.
And the other thing is because we stick with the-
the patient needs to stick the hemodialysis schedule
from the hospital,
so it's gonna be, like,
lower their quality of life
because, you know, the schedule times.
- Yep, so they have to meet different schedules.
Yeah, so what method are you using for artificial kidney?
Are you doing-
What about it that you're doing?
- Yeah, we proposed new methods to do the filtration.
You know, in hemodialysis,
instead of using hollow fiber membrane,
and let the blood contact directly with the membrane.
So all the blood cells
can be contact with the membrane as well
in the filtration process.
And, you know, in the filtration process
the pressure needs to be applied,
so that's why blood cells can be damaged
when they go through the filtration all the time like that.
So, blood cell damage, the membrane can get fouling
because of the protein adhesion on the membrane surface,
and the other thing can be
membrane can make the cell be damaged.
you know there's a fight of coagulation
when the blood cells contact with the membrane
they're gonna be-
that's gonna make the defense system work
and then coagulation happens
that's why the filtration efficiency decreases.
So, we want to separate between blood cells and plasma
and just doing filtration on plasma,
yeah, so we can somehow get a better filtration.
- So, you're looking at both filtration and separation
of the function of the kidneys,
so essentially, are you using any-
what's the set up?
Like, do you run an experiment for it?
- Yeah, yeah.
- Okay, do you wanna tell us about your experiment?
- An interesting question.
So, what we do is, we build a system, you can see in here,
with a pump
and we pump the fluid from here to the device
and we do the 3D printing for the device
and divide with the size of kidney
need to function the filtration with the membrane
in the middle of it.
You can see we measure here, the pressure
inlet and outlet.
I can show you the device.
So, one of our 3D printer device here
we have the- he has an O-ring
and we have the micro channel with a spacer we put in.
And this one, with this one
we can improve the filtration efficiency.
That's what we're studying about.
Yeah, and the whole method is
how to improve the efficiency of the filtration
and how to reduce the damage on cells on the filtration
and how to make the system portable or implantable.
- Okay.
So the solution here,
because we know that hemodialysis
is the filtration of blood,
what solution are you using here?
- Yeah, we're making some blood mimicking solution
for the first stage.
So we use glycerol and water
and certain gum
to mimic the blood behavior.
- Okay
- Yeah, and with plasma mimicking solution
we used nanoparticles
and some protein to mimic the plasma filtration
So, the filtration result here,
will, like, you see some permeate here.
- Yep.
- So, we will take the permeate into the device
into the container and bring it to the NanoSight
to check the nanoparticle concentration
and also check it with the microscope
to see how the fouling happened
and how the filtration efficiency increased.
- Hey, Bac,
Do you wanna tell us what this piece of equipment is?
- So, I told you before,
we make some 3D printed parts for artificial kidney.
So we check the microstructure in here of the part
and you can see we put some microstructure in here.
Yeah, so with that we can check through the microscope,
and we also check the membrane structure as well.
so we can see here the structure,
the part that I'm presenting.
So we see the erode and we fix the erode
for the better achieve that we want for filtration.
- So what's this equipment here?
Do you wanna tell us something about this?
- So, you know we do plasma filtration?
So we take some sample of what's being filtered
and we have some permeate concentration
of the nano particle inside the solution.
So we check the concentration and particle size
for the filtration.
So we use that NanoSight machine.
So what you can see is a sample being taken from here
and putting into the disk chamber
and you can see the laser go down there
and we have the particles as it shows in the screen,
and when you run the script,
run the machine
it can show you the
It can show you the concentration
it can calculate the particle size
and you have the information
about how good or bad the filtration is.
- So, you're looking at the particle size
and the concentration from this machine
from the filtration stuff that you have?
- Yeah, exactly. Yeah.
I can show you here, the running of this.
So, you see it is recording now.
- Yep.
- So, it's asked about temperature
and some stuff like that.
So after recording the pictures,
it has count and concentration
and we can see it calculate the particle size here.
You can see the particle size about a hundred nanometers,
and the concentration.
- So it sounds very comprehensive.
Is there any challenges that you're facing?
- Yes, definitely. (laughs)
Challenges will remain
in terms of making the system being biocompatible.
So all the material used
Later, for example, if we put something like this,
the chip, on a portable device and we bring it
so all the materials there should be compatible
with our blood and our defense system,
So its not making any bad change in people's health.
And, also the system should be miniaturized,
making it smaller and still keeping the function of kidney,
which is very hard, you know.
The kidney can filter, like,
one liter of blood within a minute.
So within five minutes,
the whole blood in our body being filtered
and all the toxic substances, like urea and creatinine
being removed.
So we want to do the same, but yeah,
it's gonna be a challenge for us.
- Yep, okay.
So how do you think
that the research will be further developed?
'Cause it sounds like a very interesting one.
So how do you think it can be further developed from here?
- Yeah, so if we can somehow improve the challenges,
solve the challenges, like miniaturization
and making the system being tested in animals and humans,
they're gonna be very good next steps for the development.
- So, putting it back to human beings and testing it for-
- Yes, yes.
- Okay.