Navigation Links
All wrapped up: K-State researcher's graphene cloak protects bacteria, leading to better images
Date:3/15/2011

MANHATTAN, KAN. -- It's a cloak that surpasses all others: a microscopic carbon cloak made of graphene that could change the way bacteria and other cells are imaged.

Vikas Berry, assistant professor of chemical engineering at Kansas State University, and his research team are wrapping bacteria with graphene to address current challenges with imaging bacteria under electron microscopes. Berry's method creates a carbon cloak that protects the bacteria, allowing them to be imaged at their natural size and increasing the image's resolution.

Graphene is a form of carbon that is only one atom thick, giving it several important properties: it's impermeable, it's the strongest nanomaterial, it's optically transparent and it has high thermal conductance.

"Graphene is the next-generation material," Berry said. "Although only an atom thick, graphene does not allow even the smallest of molecules to pass through. Furthermore, it's strong and highly flexible so it can conform to any shape."

Berry's team has been researching graphene for three years, and Berry recently saw a connection between graphene and cell imaging research. Because graphene is impermeable, he decided to use the material to preserve the size of bacterial cells imaged under high-vacuum electron microscopes.

The research results appear in the paper "Impermeable Graphenic Encasement of Bacteria," which was published in a recent issue of Nano Letters, a monthly scientific journal published by the American Chemical Society. The team's preliminary research appeared in Nature News in 2010.

The current challenge with cell imaging occurs when scientists use electron microscopes to image bacterial cells. Because these microscopes require a high vacuum, they remove water from the cells. Biological cells contain 70 to 80 percent water, and the result is a severely shrunk cell. As a result, it is challenging to obtain an accurate image of the cells and their components in their natural state.

But Berry and his team created a solution to the imaging challenge by applying graphene. The graphene acts as an impermeable cloak around the bacteria so that the cells retain water and don't shrink under the high vacuum of electron microscopes. This provides a microscopic image of the cell at its natural size.

The carbon cloaks can be wrapped around the bacteria using two methods. The first method involves putting a sheet of graphene on top of the bacteria, much like covering up with a bed sheet. The other method involves wrapping the bacteria with a graphene solution, where the graphene sheets swaddle the bacteria. In both cases the graphene sheets were functionalized with a protein to enhance binding with the bacterial cell wall.

Under the high vacuum of an electron microscope, the wrapped bacteria did not change in size for 30 minutes, giving scientists enough time to observe them. This is a direct result of the high strength and impermeability of the graphene cloak, Berry said.

Graphene's other extraordinary properties enhance the imaging resolution in microscopy. Its electron-transparency enables a clean imaging of the cells. Since graphene is a good conductor of heat and electricity, the local electronic-charging and heating is conducted off the graphene cloak, giving a clear view of the bacterial cell well. Unwrapped bacterial cells appear dark with an indistinguishable cell wall.

"Uniquely, graphene has all the properties needed to image bacteria at high resolutions," Berry said. "The project provides a very simple route to image samples in their native wet state."

The process has potential to influence future research. Scientists have always had trouble observing liquid samples under electron microscopes, but using carbon cloaks could allow them to image wet samples in a vacuum. Graphene's strong and impermeable characteristics ensure that wrapped cells can be easily imaged without degrading them. Berry said it might be possible in the future to use graphene to keep bacterium alive in a vacuum while observing its biochemistry under a microscope.

The research also paves the way for enhanced protein microscopy. Proteins act differently when they are dry and when they are in an aqueous solution. So far most protein studies have been conducted in dry phases, but Berry's research may allow proteins to be observed more in aqueous environments.

"This research could be the point of evolution for processing of sensitive samples with graphene to achieve enhanced imaging," Berry said.


'/>"/>

Contact: Vikas Berry
vberry@k-state.edu
785-532-5519
Kansas State University
Source:Eurekalert

Related biology news :

1. K-State research: Freshwater pollution costs US at least $4.3 billion a year
2. Researchers to use K-States BSL-3 Lab for $1 million study of fungus threatening wheat crops
3. K-State biologist collaborating with researchers in Africa on grassland sustainability, biodiversity
4. K-State researchers help Epitopix license the United States first E. coli O157 vaccine for cattle
5. K-State researchers work with university in Ghana to create biofuels from native tree seeds
6. K-State using Second Life island to help high school students learn earth science
7. K-State researcher finds 1918 flu resulted in current lineage of H1N1 swine influenza viruses
8. K-State host to workshop on rapid methods to detect microorganisms in food
9. Researchers from around the globe coming to K-State June 21 for workshop on Fusarium fungus
10. K-State plant pathologists develop online teaching modules used globally
11. K-State researcher, collaborators study virulence of pandemic H1N1 virus
Post Your Comments:
*Name:
*Comment:
*Email:
(Date:12/16/2016)... Research and Markets has announced the addition of the ... report to their offering. ... The biometric vehicle access system market, in terms ... from 2016 to 2021. The market is estimated to be USD ... by 2021. The growth of the biometric vehicle access system market ...
(Date:12/15/2016)... Advancements in biometrics will radically ... wellbeing (HWW), and security of vehicles by ... vehicles begin to feature fingerprint recognition, iris ... monitoring, brain wave monitoring, stress detection, fatigue ... detection. These will be driven by built-in, ...
(Date:12/8/2016)... ALAMEDA, Calif. , Dec. 8, 2016  Singulex, ... Single Molecule Counting technology, entered into a license and ... in serving science. The agreement provides Singulex access to ... Europe is used to diagnose ... the United States to aid in assessing ...
Breaking Biology News(10 mins):
(Date:1/20/2017)... BOSTON , Jan. 20, 2017 ... acquisition of Gen9, a pioneer in the synthesis ... Gen9,s unique expertise in assembling pathway-length synthetic DNA ... speed and capacity in the construction of new ... of industries. "Gen9 was founded to ...
(Date:1/19/2017)... HOUSTON , Jan. 19, 2017 /PRNewswire/ ... the formation of its Medical/Clinical Advisory Board.  This ... veterans who enhance the range and depth of ... of its novel prenatal diagnostic tests.  These experts ... strategic guidance for the company,s product development and ...
(Date:1/19/2017)... GAITHERSBURG, Md. , Jan. 19, 2017 /PRNewswire/ ... a privately-held immunotherapeutics company targeting infectious diseases, announced ... the merger of PharmAthene and Altimmune in an ... Fund, HealthCap, Truffle Capital and Redmont Capital. The ... immunotherapeutics company with four clinical stage and one ...
(Date:1/19/2017)... ... 2017 , ... FireflySci Inc. is a go-getter type of company that continues ... to two main factors. The first is the amazing customer service that the ... products all around the world. , 2016 was a tremendous sales year for FFS ...
Breaking Biology Technology: