Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

The Smallest Sight: Researchers Zoom In on the Nanoscale

04.03.2003


Researchers at the University of Rochester have created the highest resolution optical image ever, revealing structures as small as carbon nanotubes just a few billionths of an inch across. The new method should open the door to previously inaccessible chemical and structural information in samples as small as the proteins embedded in a cell’s membrane. The research appears in today’s issue of Physical Review Letters.



"This is the highest resolution optical spectroscopic measurement ever made," says Lukas Novotny, professor of optics. "There are other methods that can see smaller structures, but none use light, which is rich in information. With this technique we have a detailed spectrum for every point on a surface."

Since light is so rife with information (everything we know about the deep universe comes from teasing information from a tiny amount of light), Novotny and his colleague, visiting professor Achim Hartschuh, can determine what a piece of material is made of as well as its structure. Is the string of carbon rolled into a tube or just a string of atoms? Is a protein made of expected molecules and properly folded to be an effective medicine? And what could be the most rewarding result of the research-detecting properties of such small structures that were unknown before. Novotny and his team are also eager to learn if certain structures exhibit unknown characteristics, such as when carbon nanotubes, for instance, cross or interconnect.


The ultimate vision for the Raman microscopy project, however, is to refine the process to a point where it might revolutionize biology. "Identifying individual proteins right on the cell’s membrane has been the goal of this project from the start," says Hartschuh. Garnering the cornucopia of information light provides from the proteins on a membrane would mean scientists could understand exactly how a cell’s membrane works, opening the door to designer medicines that could kill harmful cells, repair damaged cells, or even identify never-before-seen strains of disease.

The Rochester team’s technique, called near-field Raman microscopy, illuminates the nano-sized structures with light, allowing researchers to glean far more information than any other technique. Other ultra-high resolution imaging techniques, such as atomic force microscopes, only detect the presence of objects, they don’t "see" them. Though researchers have longed wished to use light at such magnification, the laws of physics make this extremely difficult. Light travels in waves, and if an object like a nanotube or a protein is much smaller than that wavelength, it’s like trying to pick up a poppy seed with a fork-the poppy seed falls between the tines. Some efforts have been made to force light to shorter wavelengths and through tiny apertures, but these methods have their own built-in limitations, including damage to the aperture itself.

Novotny and Hartschuh sharpen a gold wire to a point just a few billionths of an inch across. A laser then shines against the side of the gold tip, inciting electrons inside it to oscillate. These oscillations create a tiny bubble of electromagnetic energy at the tip, which interacts with the vibrations of the atoms in the sample. This interaction, called Raman scattering, releases packets of light from the sample at specific frequencies that can be detected and used to identify the chemical composition of the material.

In about two years, Novotny and Hartschuh think they will be able to refine the system, already with a resolution of 20 nanometers (billionths of a meter), so that they can image proteins, which are only 5 to 20 nanometers wide. To do that they will try to get the point of the gold tip sharper still, or even experiment with different shaped points. Then the trick will be keeping the tip "alive," meaning using it without incurring the least damaging bump or scrape-a difficult task when hovering only a few nanometers above the scanned sample. If all goes well, the research team may try to push the technology even further to derive first-ever optical images of smaller molecules.

The research was supported by a grant from the National Science Foundation.

Jonathan Sherwood | University of Rochester
Further information:
http://www.rochester.edu/pr/News/NewsReleases/scitech/novotny-nearfield.html

More articles from Physics and Astronomy:

nachricht Squeezing light at the nanoscale
17.06.2018 | Harvard John A. Paulson School of Engineering and Applied Sciences

nachricht The Fraunhofer IAF is a »Landmark in the Land of Ideas«
15.06.2018 | Fraunhofer-Institut für Angewandte Festkörperphysik IAF

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: AchemAsia 2019 will take place in Shanghai

Moving into its fourth decade, AchemAsia is setting out for new horizons: The International Expo and Innovation Forum for Sustainable Chemical Production will take place from 21-23 May 2019 in Shanghai, China. With an updated event profile, the eleventh edition focusses on topics that are especially relevant for the Chinese process industry, putting a strong emphasis on sustainability and innovation.

Founded in 1989 as a spin-off of ACHEMA to cater to the needs of China’s then developing industry, AchemAsia has since grown into a platform where the latest...

Im Focus: First real-time test of Li-Fi utilization for the industrial Internet of Things

The BMBF-funded OWICELLS project was successfully completed with a final presentation at the BMW plant in Munich. The presentation demonstrated a Li-Fi communication with a mobile robot, while the robot carried out usual production processes (welding, moving and testing parts) in a 5x5m² production cell. The robust, optical wireless transmission is based on spatial diversity; in other words, data is sent and received simultaneously by several LEDs and several photodiodes. The system can transmit data at more than 100 Mbit/s and five milliseconds latency.

Modern production technologies in the automobile industry must become more flexible in order to fulfil individual customer requirements.

Im Focus: Sharp images with flexible fibers

An international team of scientists has discovered a new way to transfer image information through multimodal fibers with almost no distortion - even if the fiber is bent. The results of the study, to which scientist from the Leibniz-Institute of Photonic Technology Jena (Leibniz IPHT) contributed, were published on 6thJune in the highly-cited journal Physical Review Letters.

Endoscopes allow doctors to see into a patient’s body like through a keyhole. Typically, the images are transmitted via a bundle of several hundreds of optical...

Im Focus: Photoexcited graphene puzzle solved

A boost for graphene-based light detectors

Light detection and control lies at the heart of many modern device applications, such as smartphone cameras. Using graphene as a light-sensitive material for...

Im Focus: Water is not the same as water

Water molecules exist in two different forms with almost identical physical properties. For the first time, researchers have succeeded in separating the two forms to show that they can exhibit different chemical reactivities. These results were reported by researchers from the University of Basel and their colleagues in Hamburg in the scientific journal Nature Communications.

From a chemical perspective, water is a molecule in which a single oxygen atom is linked to two hydrogen atoms. It is less well known that water exists in two...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

Munich conference on asteroid detection, tracking and defense

13.06.2018 | Event News

2nd International Baltic Earth Conference in Denmark: “The Baltic Sea region in Transition”

08.06.2018 | Event News

ISEKI_Food 2018: Conference with Holistic View of Food Production

05.06.2018 | Event News

 
Latest News

A sprinkle of platinum nanoparticles onto graphene makes brain probes more sensitive

15.06.2018 | Materials Sciences

100 % Organic Farming in Bhutan – a Realistic Target?

15.06.2018 | Ecology, The Environment and Conservation

Perovskite-silicon solar cell research collaboration hits 25.2% efficiency

15.06.2018 | Power and Electrical Engineering

VideoLinks
Science & Research
Overview of more VideoLinks >>>