Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Biting its Own Tail

20.04.2010
Nanocontainer with an integrated switch

The ouroboros (ancient Greek for “tail devourer”) is a motif found in many cultures: a snake biting its own tail, it symbolizes eternity and cycles. Julius Rebek, Jr. and Fabien Durola (The Scripps Research Institute, La Jolla, USA) have now constructed a molecular tail devourer, and have named this new class of compound “ouroborand”. As the researchers report in the journal Angewandte Chemie, their tail-biter is a molecular “machine”, which functions as a nanocontainer with a built-in switch that regulates access to the cavity.

Molecular machines and nanoscopic components imitate—at least theoretically—the functions of their macroscopic analogues. For example, nanoscopic capsules can act as reaction vessels, molecules with parts that rotate relative to each other to imitate rotors, and various types of on/off switches.

The ouroborand made by the American research duo is a molecule consisting of multiple parts. A cavity that can take up guest molecules serves as a container. At its edge, the container has a switchable rotor (a bipyridyl unit) to which an intramolecular guest is attached like a hand at the end of a coupling arm of appropriate length. The rotor is turned so that the hand at the end of the arm sits inside the container. The container is thus blocked and not accessible to other molecules; it is switched to closed. In this conformation it is reminiscent of a snake that is swallowing its own tail, the ouroboros.

If zinc ions are added to the solution, they trigger a switching mechanism: the rotor has two binding sites for zinc ions. In order for both to bind an ion, the rotor must make a half-turn. The coupling arm turns with it, which causes the hand to be pulled out of the container. The vessel is now free and accessible to other molecules; it is switched to open. If the zinc ions are taken back out of the solution, the rotor then turns back to the starting position and the hand throws the foreign molecule back out of the container.

Author: Julius Rebek, Jr., Scripps Research Institute, La Jolla (USA), http://www.scripps.edu/skaggs/rebek/

Title: The Ouroborand: A Cavitand with a Coordination-Driven Switching Device

Angewandte Chemie International Edition 2010, 49, No. 18, 3189–3191, Permalink to the article: http://dx.doi.org/10.1002/anie.200906753

Julius Rebek, Jr. | Angewandte Chemie
Further information:
http://pressroom.angewandte.org
http://www.scripps.edu/skaggs/rebek/

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 >>>