Researchers Using New Material to Solve Challenges in Biology


Uploaded by KState on 27.03.2012

Transcript:
Vikas Berry>> The focus of my research group over the last four years or so has been on
graphene. It is a material that was discovered in 2004 so graphene is essentially a sheet
of carbon atoms linked to one another. Another form of carbon that we all know is diamond.
In the case of diamond the bonding between carbon atoms is sp3. What that means is, each
carbon is attached to four other carbon atoms and that?s why you don?t get a sheet, but
you get a three-dimensional material so graphene is very different from diamond.
Phong Nguyen>> The method we use to produce graphene sheet is the Chemical Vapor Deposition
System. Once the system is closed, we will put it in the vacuum. Then we start to flow
hydrogen gas first and then we heat the whole process up to 1,000 degrees. Once the system
is under 1,000 degrees Celsius, we will start to pump methane gas into it and then there
is a one atom thick layer of graphene on top of it.
Vikas Berry>> For one of our recent projects, we took bacterial cells and wrapped them with
graphene. Now graphene is a material which has high conductivity and it is the most impermeable
material in the world and it is also the most strongest material in the world. So we used
these three properties of graphene to build or to solve a problem in electron microscopy.
Electron microscopes work under vacuum. The cells have about 70 percent water in them,
right? So when you put these cells inside an electron microscope, first thing that happens
is all the water from the bacteria, it oozes out because of the vacuum and the cell shrinks
in size. So what we did was we took graphene and we wrapped the cells with graphene sheets
so now you have a way to image the cell as it is without it losing its water. Most importantly
you get original sized images, which has been a big challenge in electron microscopy especially
for cells.