Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Synthetic Cells Shed Biological Insights While Delivering Battery Power

22.10.2009
Trying to understand the complex workings of a biological cell by teasing out the function of every molecule within it is a daunting task. But by making synthetic cells that include just a few chemical processes, researchers can study cellular machinery one manageable piece at a time.

A new paper* from researchers at Yale University and the National Institute of Standards and Technology (NIST) describes a highly simplified model cell that not only sheds light on the way certain real cells generate electric voltages, but also acts as a tiny battery that could offer a practical alternative to conventional solid-state energy-generating devices.

Each synthetic cell built by NIST engineer David LaVan and his colleagues has a droplet of a water-based solution containing a salt—potassium and chloride ions—enclosed within a wall made of a lipid, a molecule with one end that is attracted to water molecules while the other end repels them. When two of these "cells" come into contact, the water-repelling lipid ends that form their outsides touch, creating a stable double bilayer that separates the two cells' interiors, just as actual cell membranes do.

If the researchers only did that much, nothing interesting would happen, but they also inserted into the bilayer a modified form of a protein, alpha-hemolysin, made by the bacterium Staphylococcus aureus. These embedded proteins create pores that act as channels for ions, mimicking the pores in a biological cell. "This preferentially allows either positive or negative ions to pass through the bilayer and creates a voltage across it," LaVan says. "We can harness this voltage to generate electric current."

If the solutions in the two cells start with different salt concentrations, then poking thin metal electrodes into the droplets creates a small battery: electrons will flow through a circuit connected to the electrodes, counterbalancing the ion flow through the channels. As this happens, the ion concentrations in the droplets eventually equalize as the system discharges its electric potential.

Building synthetic versions of complex real cells—such as those that enable an electric eel to zap its prey [see Tech Beat Oct 1, 2008]—is far too difficult a task for now, says LaVan. So the researchers instead created this far simpler system whose performance they could understand in terms a handful of basic properties, including the size of the droplets, the concentration of the aqueous solutions, and the number of ion channels in the barrier between the two cells.

A tiny battery with two droplets, each containing just 200 nanoliters of solution, could deliver electricity for almost 10 minutes. A bigger system, with a total volume of almost 11 microliters, lasted more than four hours. In terms of the energy it can deliver for a given volume, the biological battery is only about one-twentieth as effective as a conventional lead-acid battery. But in its ability to convert chemical into electrical energy, the synthetic cell has an efficiency of about 10 per cent, which compares well with solid-state devices that generate electricity from heat, light, or mechanical stress—so that synthetic cells may one day take their place in the nanotechnology toolbox.

*J. Xu, F.J. Sigworth, and D.A. LaVan. Synthetic Protocells to Mimic and Test Cell Function. Advanced Materials, published online Oct. 1, 2009 (DOI: 10.1002/adma.200901945).

Ben Stein | Newswise Science News
Further information:
http://www.nist.gov

More articles from Life Sciences:

nachricht Researchers identify potentially druggable mutant p53 proteins that promote cancer growth
09.12.2016 | Cold Spring Harbor Laboratory

nachricht Plant-based substance boosts eyelash growth
09.12.2016 | Fraunhofer-Institut für Angewandte Polymerforschung IAP

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: Electron highway inside crystal

Physicists of the University of Würzburg have made an astonishing discovery in a specific type of topological insulators. The effect is due to the structure of the materials used. The researchers have now published their work in the journal Science.

Topological insulators are currently the hot topic in physics according to the newspaper Neue Zürcher Zeitung. Only a few weeks ago, their importance was...

Im Focus: Significantly more productivity in USP lasers

In recent years, lasers with ultrashort pulses (USP) down to the femtosecond range have become established on an industrial scale. They could advance some applications with the much-lauded “cold ablation” – if that meant they would then achieve more throughput. A new generation of process engineering that will address this issue in particular will be discussed at the “4th UKP Workshop – Ultrafast Laser Technology” in April 2017.

Even back in the 1990s, scientists were comparing materials processing with nanosecond, picosecond and femtosesecond pulses. The result was surprising:...

Im Focus: Shape matters when light meets atom

Mapping the interaction of a single atom with a single photon may inform design of quantum devices

Have you ever wondered how you see the world? Vision is about photons of light, which are packets of energy, interacting with the atoms or molecules in what...

Im Focus: Novel silicon etching technique crafts 3-D gradient refractive index micro-optics

A multi-institutional research collaboration has created a novel approach for fabricating three-dimensional micro-optics through the shape-defined formation of porous silicon (PSi), with broad impacts in integrated optoelectronics, imaging, and photovoltaics.

Working with colleagues at Stanford and The Dow Chemical Company, researchers at the University of Illinois at Urbana-Champaign fabricated 3-D birefringent...

Im Focus: Quantum Particles Form Droplets

In experiments with magnetic atoms conducted at extremely low temperatures, scientists have demonstrated a unique phase of matter: The atoms form a new type of quantum liquid or quantum droplet state. These so called quantum droplets may preserve their form in absence of external confinement because of quantum effects. The joint team of experimental physicists from Innsbruck and theoretical physicists from Hannover report on their findings in the journal Physical Review X.

“Our Quantum droplets are in the gas phase but they still drop like a rock,” explains experimental physicist Francesca Ferlaino when talking about the...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

ICTM Conference 2017: Production technology for turbomachine manufacturing of the future

16.11.2016 | Event News

Innovation Day Laser Technology – Laser Additive Manufacturing

01.11.2016 | Event News

#IC2S2: When Social Science meets Computer Science - GESIS will host the IC2S2 conference 2017

14.10.2016 | Event News

 
Latest News

Researchers identify potentially druggable mutant p53 proteins that promote cancer growth

09.12.2016 | Life Sciences

Scientists produce a new roadmap for guiding development & conservation in the Amazon

09.12.2016 | Ecology, The Environment and Conservation

Satellites, airport visibility readings shed light on troops' exposure to air pollution

09.12.2016 | Health and Medicine

VideoLinks
B2B-VideoLinks
More VideoLinks >>>