Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

It’s the Water: Graphene Balloon Yields Unprecedented Images of Hydrated Protein Molecules

06.02.2014
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.


Chanhui Wang

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.

“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.

An article on their work, “High-Resolution Electron Microscopy and Spectroscopy of Ferritin in Biocompatible Graphene Liquid Cells and Graphene Sandwiches,” ( http://onlinelibrary.wiley.com/doi/10.1002/adma.201306069/abstract )was published Feb. 4 in Advanced Materials. Qiao Qiao, formerly a graduate student in Klie's UIC lab and now a postdoctoral fellow at Vanderbilt University, is also a coauthor on the study.

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.

Tolou Shokuhfar, cell 906-370-7657, tshokuhf@mtu.edu
Marcia Goodrich, writer, mlgoodri@mtu.edu, 906-487-2343

Marcia Goodrich | Newswise
Further information:
http://www.mtu.edu

Further reports about: Molecules Protein Water Snake carbon atom electron microscope graphene hydrated

More articles from Life Sciences:

nachricht How brains surrender to sleep
23.06.2017 | IMP - Forschungsinstitut für Molekulare Pathologie GmbH

nachricht A new technique isolates neuronal activity during memory consolidation
22.06.2017 | Spanish National Research Council (CSIC)

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Can we see monkeys from space? Emerging technologies to map biodiversity

An international team of scientists has proposed a new multi-disciplinary approach in which an array of new technologies will allow us to map biodiversity and the risks that wildlife is facing at the scale of whole landscapes. The findings are published in Nature Ecology and Evolution. This international research is led by the Kunming Institute of Zoology from China, University of East Anglia, University of Leicester and the Leibniz Institute for Zoo and Wildlife Research.

Using a combination of satellite and ground data, the team proposes that it is now possible to map biodiversity with an accuracy that has not been previously...

Im Focus: Climate satellite: Tracking methane with robust laser technology

Heatwaves in the Arctic, longer periods of vegetation in Europe, severe floods in West Africa – starting in 2021, scientists want to explore the emissions of the greenhouse gas methane with the German-French satellite MERLIN. This is made possible by a new robust laser system of the Fraunhofer Institute for Laser Technology ILT in Aachen, which achieves unprecedented measurement accuracy.

Methane is primarily the result of the decomposition of organic matter. The gas has a 25 times greater warming potential than carbon dioxide, but is not as...

Im Focus: How protons move through a fuel cell

Hydrogen is regarded as the energy source of the future: It is produced with solar power and can be used to generate heat and electricity in fuel cells. Empa researchers have now succeeded in decoding the movement of hydrogen ions in crystals – a key step towards more efficient energy conversion in the hydrogen industry of tomorrow.

As charge carriers, electrons and ions play the leading role in electrochemical energy storage devices and converters such as batteries and fuel cells. Proton...

Im Focus: A unique data centre for cosmological simulations

Scientists from the Excellence Cluster Universe at the Ludwig-Maximilians-Universität Munich have establised "Cosmowebportal", a unique data centre for cosmological simulations located at the Leibniz Supercomputing Centre (LRZ) of the Bavarian Academy of Sciences. The complete results of a series of large hydrodynamical cosmological simulations are available, with data volumes typically exceeding several hundred terabytes. Scientists worldwide can interactively explore these complex simulations via a web interface and directly access the results.

With current telescopes, scientists can observe our Universe’s galaxies and galaxy clusters and their distribution along an invisible cosmic web. From the...

Im Focus: Scientists develop molecular thermometer for contactless measurement using infrared light

Temperature measurements possible even on the smallest scale / Molecular ruby for use in material sciences, biology, and medicine

Chemists at Johannes Gutenberg University Mainz (JGU) in cooperation with researchers of the German Federal Institute for Materials Research and Testing (BAM)...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Plants are networkers

19.06.2017 | Event News

Digital Survival Training for Executives

13.06.2017 | Event News

Global Learning Council Summit 2017

13.06.2017 | Event News

 
Latest News

Quantum thermometer or optical refrigerator?

23.06.2017 | Physics and Astronomy

A 100-year-old physics problem has been solved at EPFL

23.06.2017 | Physics and Astronomy

Equipping form with function

23.06.2017 | Information Technology

VideoLinks
B2B-VideoLinks
More VideoLinks >>>