Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Rice rolls out new nanocars

04.02.2009
Fluorescent imaging shows models operate at room temperature

This year's model isn't your father's nanocar. It runs cool.

The drivers of Rice University's nanocars were surprised to find modified versions of their creation have the ability to roll at room temperature. While practical applications for the tiny machines may be years away, the breakthrough suggests they'll be easier to adapt to a wider range of uses than the originals, which had to be heated to 200 degrees Celsius before they could move across a surface.

The nanocar was a sensation when introduced in 2005 by the lab of James Tour, Rice's Chao Professor of Chemistry and a professor of mechanical engineering and materials science and computer science.

Tour's original single-molecule car had buckyball wheels and flexible axles, and it served as a proof-of-concept for the manufacture of machines at the nanoscale. A light-activated paddlewheel motor was later attached to propel it, and the wheels were changed from buckyballs to carboranes. These were easier to synthesize and permitted the motor to move, because the buckyball wheels trapped the light energy that served as fuel before the motor could turn. Since then, nanotrucks, nanobackhoes and other models have been added to the Rice showroom.

A large-scale representation of the nanocar made its public debut in Houston's famous Art Car Parade last year.

Rice's Stephan Link, an assistant professor of chemistry who specializes in plasmonics, took the wheel for a new series of experiments that built upon Tour's pioneering work. Link's primary achievement was using single-molecule fluorescence imaging to track the tiny vehicles, as opposed to the scanning tunneling microscopy (STM) used in earlier experiments. STM imaging can capture matter at an atomic scale, but the technique requires the target to be on a conductive substrate. Not so with fluorescent imaging.

A paper on the new research published this month in ACS Nano was authored by Link; Tour; Anatoly Kolomeisky, associate professor of chemistry and chemical and biomolecular engineering; postdoc Guillaume Vives; graduate students Saumyakanti Khatua and Jason M. Guerrero; and undergraduate Kevin Claytor.

"We thought, 'We're just going to take an image, and nothing's going to happen,'" said Link of the team's initial success in attaching fluorescent dye trailers to the nanocars. "We were worrying about how to build a temperature stage around it and how to heat it and how to make it move.

"To my surprise, my students came back and said, 'They moved!'"

Sure enough, time-lapsed films monitoring an area 10-by-10 microns square showed the cars, which appear as fluorescing dots, zigging and zagging on a standard glass slide. Link said the cars moved an average 4.1 nanometers (or two nanocar lengths) per second.

"It took us another year to quantify it," said Link, noting as key the development of a new tracking algorithm by Claytor that will be the subject of a future paper.

The simplest technique for finding moving nanocars was precisely the way astronomers find distant cosmic bodies: Look at a series of images, and the dots that move are winners. The ones that don't are either fluorescing molecules sitting by themselves or nanocars stuck in park.

The dye – tetramethylrhodamine isothiocyanate – had the added attraction of emitting a polarized signal. Since dye molecules tended to line up with the chassis, the researchers could always tell which way the cars were pointed.

Link hoped cars with dye embedded into the chassis can be built that would eliminate the drag created by the fluorescent trailer. He speculated that putting six wheels instead of four on a nanocar could also help keep it moving in one direction, much like a tank with treads.

"Now that we see movement, the challenge is to take it to the next level and make it go from point A to point B. That's not going to be easy." Creating nanotracks or roads may be part of the solution, Link said.

All the research is directed at the ultimate goal of building machines from the bottom up in much the same way proteins are built to carry out tasks in nature.

"In terms of computing, having these single molecules be addressable is a goal everybody wants to reach," said Link. "And to understand and emulate biophysics and biomechanics, to build a device based on what nature gives us, is of course one of the dreams of nanotechnology."

David Ruth | EurekAlert!
Further information:
http://www.rice.edu
http://www.owlnet.rice.edu/~slink/nanocar.htm

More articles from Physics and Astronomy:

nachricht From rocks in Colorado, evidence of a 'chaotic solar system'
23.02.2017 | University of Wisconsin-Madison

nachricht Prediction: More gas-giants will be found orbiting Sun-like stars
22.02.2017 | Carnegie Institution for Science

All articles from Physics and Astronomy >>>

The most recent press releases about innovation >>>

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

Im Focus: Breakthrough with a chain of gold atoms

In the field of nanoscience, an international team of physicists with participants from Konstanz has achieved a breakthrough in understanding heat transport

In the field of nanoscience, an international team of physicists with participants from Konstanz has achieved a breakthrough in understanding heat transport

Im Focus: DNA repair: a new letter in the cell alphabet

Results reveal how discoveries may be hidden in scientific “blind spots”

Cells need to repair damaged DNA in our genes to prevent the development of cancer and other diseases. Our cells therefore activate and send “repair-proteins”...

Im Focus: Dresdner scientists print tomorrow’s world

The Fraunhofer IWS Dresden and Technische Universität Dresden inaugurated their jointly operated Center for Additive Manufacturing Dresden (AMCD) with a festive ceremony on February 7, 2017. Scientists from various disciplines perform research on materials, additive manufacturing processes and innovative technologies, which build up components in a layer by layer process. This technology opens up new horizons for component design and combinations of functions. For example during fabrication, electrical conductors and sensors are already able to be additively manufactured into components. They provide information about stress conditions of a product during operation.

The 3D-printing technology, or additive manufacturing as it is often called, has long made the step out of scientific research laboratories into industrial...

Im Focus: Mimicking nature's cellular architectures via 3-D printing

Research offers new level of control over the structure of 3-D printed materials

Nature does amazing things with limited design materials. Grass, for example, can support its own weight, resist strong wind loads, and recover after being...

Im Focus: Three Magnetic States for Each Hole

Nanometer-scale magnetic perforated grids could create new possibilities for computing. Together with international colleagues, scientists from the Helmholtz Zentrum Dresden-Rossendorf (HZDR) have shown how a cobalt grid can be reliably programmed at room temperature. In addition they discovered that for every hole ("antidot") three magnetic states can be configured. The results have been published in the journal "Scientific Reports".

Physicist Dr. Rantej Bali from the HZDR, together with scientists from Singapore and Australia, designed a special grid structure in a thin layer of cobalt in...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Booth and panel discussion – The Lindau Nobel Laureate Meetings at the AAAS 2017 Annual Meeting

13.02.2017 | Event News

Complex Loading versus Hidden Reserves

10.02.2017 | Event News

International Conference on Crystal Growth in Freiburg

09.02.2017 | Event News

 
Latest News

From rocks in Colorado, evidence of a 'chaotic solar system'

23.02.2017 | Physics and Astronomy

'Quartz' crystals at the Earth's core power its magnetic field

23.02.2017 | Earth Sciences

Antimicrobial substances identified in Komodo dragon blood

23.02.2017 | Life Sciences

VideoLinks
B2B-VideoLinks
More VideoLinks >>>