Featured Research

from universities, journals, and other organizations

It's the water: Graphene balloon yields unprecedented images of hydrated protein molecules

Date:
February 5, 2014
Source:
Michigan Technological University
Summary:
An ingenious new technique may open up new vistas for scientists seeking to understand health and disease at the most fundamental level.

In this image generated by an electron microscope, the white dots are the protein ferritin. The dark circle in the middle is a bubble trapped within the graphene capsule enclosing the sample, proving the existence of a liquid.
Credit: Chanhui Wang

A graphene water balloon may soon open up new vistas for scientists seeking to understand health and disease at the most fundamental level.

Electron microscopes already provide amazingly clear images of samples just a few nanometers across. But if you want a good look at living tissue, look again.

"You can't put liquid in an electron microscope," says Tolou Shokuhfar, of Michigan Technological University. "So, if you have a hydrated sample -- and all living things are hydrated -- you have to freeze it, like a blueberry in an ice cube, and cut it into a million thin pieces, so the electrons can pass through. Only then can you image it to see what's going on."

After such treatment, the blueberry isn't what it was, and neither is human tissue. Shokuhfar, an assistant professor of mechanical engineering-engineering mechanics, wondered if there might be a way to make electron microscopes more friendly to biological samples. That way, you might get a much better view of what's really going on at the sub-cellular level.

So she joined colleagues at the University of Illinois-Chicago (UIC), and together they found a way. "You don't need to freeze the blueberry, you don't need to slice it up with a diamond knife," she said. "You just put it in the electron microscope, and you can get down and see the atoms."

The trick was to encapsulate the sample so that all the water stayed put while the electrons passed through freely. To do that, the team, including Robert F. Klie, an associate professor of physics and mechanical and industrial engineering at UIC, and UIC graduate student Canhui Wang, turned to graphene.

"Graphene is just a single layer of carbon atoms, and electrons can go through it easily, but water does not," Klie said. "If you put a drop of water on graphene and top it with graphene, it forms this little balloon of water." The graphene is strong enough to hold the water inside, even within the vacuum of an electron microscope.

The team tried their technique on a biochemical that plays a major role in human health: ferritin. "It's a protein that stores and releases iron, which is critical for many body functions, and if ferritin isn't working right, it may be contributing to lots of diseases, including Alzheimer's and cancer," Shokuhfar said.

The team made a microscopic sandwich, with ferritin immersed in water as the filling and graphene as the bread, and sealed the edges. Then, using a scanning transmission electron microscope, they captured a variety of images showing ferritin's atomic structure. In addition, they used a special type of spectroscopy to identify various atomic and electronic structures within the ferritin. Those images showed that the ferritin was releasing iron and pinpointed its specific form.

If the technique were used to compare ferritin taken from diseased tissue with healthy ferritin, it could provide new insights into illness at the molecular level. Those discoveries could lead to new treatments. "I believe this will allow us to identify disease signatures in ferritin and many other proteins," Shokuhfar said.

The work was funded by Michigan Technological University with additional support from a National Science Foundation grant to UIC, number DMR-0959470. The research was conducted at the University of Illinois-Chicago.


Story Source:

The above story is based on materials provided by Michigan Technological University. Note: Materials may be edited for content and length.


Journal Reference:

  1. Canhui Wang, Qiao Qiao, Tolou Shokuhfar, Robert F. Klie. High-Resolution Electron Microscopy and Spectroscopy of Ferritin in Biocompatible Graphene Liquid Cells and Graphene Sandwiches. Advanced Materials, 2014; DOI: 10.1002/adma.201306069

Cite This Page:

Michigan Technological University. "It's the water: Graphene balloon yields unprecedented images of hydrated protein molecules." ScienceDaily. ScienceDaily, 5 February 2014. <www.sciencedaily.com/releases/2014/02/140205103303.htm>.
Michigan Technological University. (2014, February 5). It's the water: Graphene balloon yields unprecedented images of hydrated protein molecules. ScienceDaily. Retrieved July 31, 2014 from www.sciencedaily.com/releases/2014/02/140205103303.htm
Michigan Technological University. "It's the water: Graphene balloon yields unprecedented images of hydrated protein molecules." ScienceDaily. www.sciencedaily.com/releases/2014/02/140205103303.htm (accessed July 31, 2014).

Share This




More Matter & Energy News

Thursday, July 31, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Britain Testing Driverless Cars on Roadways

Britain Testing Driverless Cars on Roadways

AP (July 30, 2014) British officials said on Wednesday that driverless cars will be tested on roads in as many as three cities in a trial program set to begin in January. Officials said the tests will last up to three years. (July 30) Video provided by AP
Powered by NewsLook.com
Amid Drought, UCLA Sees Only Water

Amid Drought, UCLA Sees Only Water

AP (July 30, 2014) A ruptured 93-year-old water main left the UCLA campus awash in 8 million gallons of water in the middle of California's worst drought in decades. (July 30) Video provided by AP
Powered by NewsLook.com
Smartphone Powered Paper Plane Debuts at Airshow

Smartphone Powered Paper Plane Debuts at Airshow

AP (July 30, 2014) Smartphone powered paper airplane that was popular on crowdfunding website KickStarter makes its debut at Wisconsin airshow (July 30) Video provided by AP
Powered by NewsLook.com
U.K. To Allow Driverless Cars On Public Roads

U.K. To Allow Driverless Cars On Public Roads

Newsy (July 30, 2014) Driverless cars could soon become a staple on U.K. city streets, as they're set to be introduced to a few cities in 2015. Video provided by Newsy
Powered by NewsLook.com

Search ScienceDaily

Number of stories in archives: 140,361

Find with keyword(s):
Enter a keyword or phrase to search ScienceDaily for related topics and research stories.

Save/Print:
Share:

Breaking News:
from the past week

In Other News

... from NewsDaily.com

Science News

Health News

    Environment News

    Technology News



      Save/Print:
      Share:

      Free Subscriptions


      Get the latest science news with ScienceDaily's free email newsletters, updated daily and weekly. Or view hourly updated newsfeeds in your RSS reader:

      Get Social & Mobile


      Keep up to date with the latest news from ScienceDaily via social networks and mobile apps:

      Have Feedback?


      Tell us what you think of ScienceDaily -- we welcome both positive and negative comments. Have any problems using the site? Questions?
      Mobile: iPhone Android Web
      Follow: Facebook Twitter Google+
      Subscribe: RSS Feeds Email Newsletters
      Latest Headlines Health & Medicine Mind & Brain Space & Time Matter & Energy Computers & Math Plants & Animals Earth & Climate Fossils & Ruins