Models of Eel Cells Suggest Electrifying Possibilities

Oct 02, 2008
Electric eel anatomy: The first detail shows stacks of electrocytes, cells linked in series (to build up voltage) and parallel (to build up current). Second detail shows an individual cell with ion channels and pumps penetratimng the membrance, The Yale/NIST model represents the behavior of several such cells. Final detail shows an individual ion channel, one of the building blocks of the model. Image: Daniel Zukowski, Yale University

(PhysOrg.com) -- Engineers long have known that great ideas can be lifted from Mother Nature, but a new paper by researchers at Yale University and the National Institute of Standards and Technology takes it to a cellular level. Applying modern engineering design tools to one of the basic units of life, they argue that artificial cells could be built that not only replicate the electrical behavior of electric eel cells but in fact improve on them. Artificial versions of the eel’s electricity generating cells could be developed as a power source for medical implants and other tiny devices, they say.

The paper, according to NIST engineer David LaVan, is an example of the relatively new field of systems biology. “Do we understand how a cell produces electricity well enough to design one—and to optimize that design?” he asks.

Electric eels channel the output of thousands of specialized cells called electrocytes to generate electric potentials of up to 600 volts, according to biologists. The mechanism is similar to nerve cells. The arrival of a chemical signal triggers the opening of highly selective channels in a cell membrane causing sodium ions to flow in and potassium ions to flow out. The ion swap increases the voltage across the membrane, which causes even more channels to open. Past a certain point the process becomes self-perpetuating, resulting in an electric pulse traveling through the cell. The channels then close and alternate paths open to “pump” the ions back to their initial concentrations during a “resting” state.

In all, according LaVan, there are at least seven different types of channels, each with several possible variables to tweak, such as their density in the membrane. Nerve cells, which move information rather than energy, can fire rapidly but with relatively little power. Electrocytes have a slower cycle, but deliver more power for longer periods. LaVan and partner Jian Xu developed a complex numerical model to represent the conversion of ion concentrations to electrical impulses and tested it against previously published data on electrocytes and nerve cells to verify its accuracy. Then they considered how to optimize the system to maximize power output by changing the overall mix of channel types.

Their calculations show that substantial improvements are possible. One design for an artificial cell generates more than 40 percent more energy in a single pulse than a natural electrocyte. Another would produce peak power outputs over 28 percent higher.

In principle, say the authors, stacked layers of artificial cells in a cube slightly over 4 mm on a side are capable of producing continuous power output of about 300 microwatts to drive small implant devices. The individual components of such artificial cells—including a pair of artificial membranes separated by an insulated partition and ion channels that could be created by engineering proteins—already have been demonstrated by other researchers. Like the natural counterpart, the cell’s energy source would be adenosine triphosphate (ATP), synthesized from the body’s sugars and fats using tailored bacteria or mitochondria.

Citation: J. Xu and D.A. LaVan. Designing artificial cells to harness the biological ion concentration gradient. Nature Nanotechnology, published online: September 21, 2008.

Provided by National Institute of Standards and Technology

Explore further: Flower-like magnetic nanoparticles target difficult tumors

add to favorites email to friend print save as pdf

Related Stories

The super-resolution revolution

Feb 27, 2015

Cambridge scientists are part of a resolution revolution. Building powerful instruments that shatter the physical limits of optical microscopy, they are beginning to watch molecular processes as they happen, ...

Image sensors that behave like biological retinas

Feb 18, 2015

Ever since the invention of the first camera obscura and the advent of photography in the 19th century, scientists have been fascinated by the use of light sensors to capture the world around us from the ...

Recommended for you

Electrons moving along defined snake states

5 hours ago

Physicists at the University of Basel have shown for the first time that electrons in graphene can be moved along a predefined path. This movement occurs entirely without loss and could provide a basis for ...

New nanodevice defeats drug resistance

22 hours ago

Chemotherapy often shrinks tumors at first, but as cancer cells become resistant to drug treatment, tumors can grow back. A new nanodevice developed by MIT researchers can help overcome that by first blocking ...

Glass coating improves battery performance

23 hours ago

Lithium-sulfur batteries have been a hot topic in battery research because of their ability to produce up to 10 times more energy than conventional batteries, which means they hold great promise for applications ...

User comments : 2

Adjust slider to filter visible comments by rank

Display comments: newest first

E_L_Earnhardt
5 / 5 (1) Oct 03, 2008
ALL LIVING CELLS GENERATE ELECTRICITY. It's O.K. to start with eels, Perhaps the method used can extract energy from human cells and stop cancer!
LucFerris
not rated yet Oct 03, 2008
Yeah!

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.