Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

UC Santa Barbara researchers discover living nanoscale ’necklace’

09.11.2004


In an interdisciplinary endeavor at the University of California, Santa Barbara, a team of researchers in physics and biology have made a discovery at the nanoscale level that could be instrumental in the production of miniaturized materials with many applications. Dubbed a "living necklace," the finding was completely unexpected.

This discovery could influence the development of vehicles for chemical, drug, and gene delivery, enzyme encapsulation systems and biosensors, circuitry components, as well as templates for nanosized wires and optical materials. The findings are reported in the November 16 issue of the Proceedings of the National Academy of Sciences and published online the week of November 8.

The collaborating labs are those of Cyrus Safinya, professor of materials and physics and faculty member of the Biomolecular Science & Engineering Program, and Leslie Wilson, professor of biochemistry in the Department of Molecular, Cellular and Developmental Biology. The first author of the paper is Safinya’s graduate student Daniel Needleman. Postdoctoral researchers Uri Raviv and Miguel Ojeda-Lopez from Safinya’s group and Herbert Miller, a researcher in Wilson’s group, completed the team.



The scientists studied microtubules from the brain tissue of a cow to understand the mechanisms leading to their assembly and shape. Microtubules are nanometer-scale hollow cylinders derived from cell cytoskeleton. In an organism, microtubules and their assembled structures are critical components in a broad range of cell functions -- from providing tracks for the transport of cargo to forming the spindle structure in cell division. Their functions include the transport of neurotransmitters in neurons. The mechanism of their assembly within an organism has been poorly understood.

In the paper, the researchers report the discovery of a new type of higher order assembly of microtubules. Positively-charged large, linear molecules (tri-, tetra- and penta-valent cations) resulted in a tightly bundled hexagonal grouping of microtubules – a result that was predicted. But unexpectedly, the scientists found that small, spherical divalent cations caused the microtubules to assemble into a "necklace." They discovered distinct linear, branched and loop shaped necklaces.

Safinya and Needleman commented that from a formal theoretical physics perspective, the living necklace phase is the first experimental realization of a new type of membrane where the long microtubule molecules are oriented in the same direction but can diffuse within the living membrane. They explained that the living necklace bundle is highly dynamic and that thermal fluctuations will cause it to change shape.

The scientists envision applications based on both the tight bundle and living necklace phases. For example, metallization of necklace bundles with different sizes and shapes would yield nanomaterials with controlled optical properties.

A more original application is in the area of using the assemblies – encased by a lipid bilayer – as drug or gene carriers where each nanotube may contain a distinct chemical, as noted by the team. In delivery applications the shape of the bundle determines its property. For example, the linear necklace phase with its higher surface to volume ratio would have a larger contact area and a faster delivery rate compared to the tight bundle phase.

The work was performed using state-of-the-art synchrotron x-ray scattering techniques at the Stanford Synchrotron Radiation Laboratory combined with sophisticated electron and optical microscopy at UCSB.

Gail Gallessich | EurekAlert!
Further information:
http://www.ucsb.edu

More articles from Interdisciplinary Research:

nachricht Novel Nano-CT device creates high-resolution 3D-X-rays of tiny velvet worm legs
07.11.2017 | Technische Universität München

nachricht NRL clarifies valley polarization for electronic and optoelectronic technologies
20.10.2017 | Naval Research Laboratory

All articles from Interdisciplinary Research >>>

The most recent press releases about innovation >>>

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

Im Focus: Nanoparticles help with malaria diagnosis – new rapid test in development

The WHO reports an estimated 429,000 malaria deaths each year. The disease mostly affects tropical and subtropical regions and in particular the African continent. The Fraunhofer Institute for Silicate Research ISC teamed up with the Fraunhofer Institute for Molecular Biology and Applied Ecology IME and the Institute of Tropical Medicine at the University of Tübingen for a new test method to detect malaria parasites in blood. The idea of the research project “NanoFRET” is to develop a highly sensitive and reliable rapid diagnostic test so that patient treatment can begin as early as possible.

Malaria is caused by parasites transmitted by mosquito bite. The most dangerous form of malaria is malaria tropica. Left untreated, it is fatal in most cases....

Im Focus: A “cosmic snake” reveals the structure of remote galaxies

The formation of stars in distant galaxies is still largely unexplored. For the first time, astron-omers at the University of Geneva have now been able to closely observe a star system six billion light-years away. In doing so, they are confirming earlier simulations made by the University of Zurich. One special effect is made possible by the multiple reflections of images that run through the cosmos like a snake.

Today, astronomers have a pretty accurate idea of how stars were formed in the recent cosmic past. But do these laws also apply to older galaxies? For around a...

Im Focus: Visual intelligence is not the same as IQ

Just because someone is smart and well-motivated doesn't mean he or she can learn the visual skills needed to excel at tasks like matching fingerprints, interpreting medical X-rays, keeping track of aircraft on radar displays or forensic face matching.

That is the implication of a new study which shows for the first time that there is a broad range of differences in people's visual ability and that these...

Im Focus: Novel Nano-CT device creates high-resolution 3D-X-rays of tiny velvet worm legs

Computer Tomography (CT) is a standard procedure in hospitals, but so far, the technology has not been suitable for imaging extremely small objects. In PNAS, a team from the Technical University of Munich (TUM) describes a Nano-CT device that creates three-dimensional x-ray images at resolutions up to 100 nanometers. The first test application: Together with colleagues from the University of Kassel and Helmholtz-Zentrum Geesthacht the researchers analyzed the locomotory system of a velvet worm.

During a CT analysis, the object under investigation is x-rayed and a detector measures the respective amount of radiation absorbed from various angles....

Im Focus: Researchers Develop Data Bus for Quantum Computer

The quantum world is fragile; error correction codes are needed to protect the information stored in a quantum object from the deteriorating effects of noise. Quantum physicists in Innsbruck have developed a protocol to pass quantum information between differently encoded building blocks of a future quantum computer, such as processors and memories. Scientists may use this protocol in the future to build a data bus for quantum computers. The researchers have published their work in the journal Nature Communications.

Future quantum computers will be able to solve problems where conventional computers fail today. We are still far away from any large-scale implementation,...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Ecology Across Borders: International conference brings together 1,500 ecologists

15.11.2017 | Event News

Road into laboratory: Users discuss biaxial fatigue-testing for car and truck wheel

15.11.2017 | Event News

#Berlin5GWeek: The right network for Industry 4.0

30.10.2017 | Event News

 
Latest News

Researchers at IST Austria define function of an enigmatic synaptic protein

22.11.2017 | Life Sciences

Fine felted nanotubes: CAU research team develops new composite material made of carbon nanotubes

22.11.2017 | Materials Sciences

Women and lung cancer – the role of sex hormones

22.11.2017 | Life Sciences

VideoLinks
B2B-VideoLinks
More VideoLinks >>>