Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Small particles, big effects: How graphene nanoparticles improve the resolution of microscopes

20.11.2019

Conventional light microscopes cannot distinguish structures when they are separated by a distance smaller than, roughly, the wavelength of light. Superresolution microscopy, developed since the 1980s, lifts this limitation, using fluorescent moieties. Scientists at the Max Planck Institute for Polymer Research have now discovered that graphene nano-molecules can be used to improve this microscopy technique. These graphene nano-molecules offer a number of substantial advantages over the materials previously used, making superresolution microscopy even more versatile.

Microscopy is an important investigation method, in physics, biology, medicine, and many other sciences. However, it has one disadvantage: its resolution is limited by physical principles. Structures can only be imaged if they are separated by a distance greater than half the wavelength of light. With blue light, this corresponds to a distance of approximately 200 nanometers, i.e., 200 millionths of a millimeter.


Nanoparticles of graphene flash irregularly when excited with light. This results in higher resolution in microscopy.

© MPI-P

This limit can be circumvented using superresolution microscopy. Today there are a number of different such approaches. In the type of superresolution microscopy applied here, fluorescent particles are excited by light and re-emit light at a slightly different wavelength, i.e. a slightly different color.

The position of these fluorescent particles can be determined with higher precision than given by the wavelength of the light: If they are blinking randomly, two neighbouring particles typically do not light up simultaneously – this means that their signals do not overlap and thus the positions of the individual particles can be determined independently of each other, so that even at very small distances the particles can be imaged separately, i.e. "resolved".

Researchers at the MPI-P have now shown that nanoparticles from graphene – so-called nanographenes, consisting of a carbon layer only one atom thick - have properties that are ideal for this special microscopy technique.

In the past, several fluorescent materials have been used for this type of microscopy, including dyes, so-called quantum dots, and fluorescent proteins. Nanographenes are as good as the best of these materials in terms of their optical properties. In addition to their excellent optical properties, nanographenes are non-toxic, very small, and, most notably and different from all other materials, their flashing frequency is robust and independent of their environment.

This means that nanographene can be used in air, aqueous solutions and other solvents - making it a very versatile fluorophore. Nanographenes can further be readily modified so that they only adhere to certain interesting locations on a sample, e.g., a specific organelle in a cell.

"We have compared nanographene with the gold standard in this microscopy technique - the organic dye Alexa 647," says Prof. Mischa Bonn, director at the MPI-P. "We found that nanographene is as efficient as this dye, i.e., it can convert as much of the incident light into a different color, but doesn’t require a specifically tailored environment that Alexa requires.“

To test the nanographene produced at the Max Planck Institute for Polymer Research, the scientists collaborated with Prof. Christoph Cremer's group at the Institute of Molecular Biology (IMB) in Mainz. The researchers prepared a glass surface with nanometer-sized fissures.

Here, nanographene particles were applied, which were mainly deposited in the gaps. In comparison with conventional microscopy, they were able to show that the resolution could be increased by a factor of 10 using graphene nanoparticles.

The scientists see the development of their material as an important step in superresolution microscopy. They have now published their results in the renowned journal "Angewandte Chemie".

Wissenschaftliche Ansprechpartner:

Prof. Dr. Mischa Bonn
Max Planck Institute for Polymer Research
Tel.: +49 6131 379-161
Email: bonn@mpip-mainz.mpg.de

Prof. Dr. Christoph Cremer
Institute for Molecular Biology (IMB)
Tel.: +49 6131 39-21518
EMail: c.cremer@imb-mainz.de

Dr. Christian Schneider | Max-Planck-Institut für Polymerforschung
Further information:
http://www.mpip-mainz.mpg.de/

More articles from Materials Sciences:

nachricht Miniature double glazing: Material developed which is heat-insulating and heat-conducting at the same time
17.01.2020 | Max-Planck-Institut für Polymerforschung

nachricht 3D Printing: New high-Tech Device for Bremen Material Scientists
16.01.2020 | Universität Bremen

All articles from Materials Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: Miniature double glazing: Material developed which is heat-insulating and heat-conducting at the same time

Styrofoam or copper - both materials have very different properties with regard to their ability to conduct heat. Scientists at the Max Planck Institute for Polymer Research (MPI-P) in Mainz and the University of Bayreuth have now jointly developed and characterized a novel, extremely thin and transparent material that has different thermal conduction properties depending on the direction. While it can conduct heat extremely well in one direction, it shows good thermal insulation in the other direction.

Thermal insulation and thermal conduction play a crucial role in our everyday lives - from computer processors, where it is important to dissipate heat as...

Im Focus: Fraunhofer IAF establishes an application laboratory for quantum sensors

In order to advance the transfer of research developments from the field of quantum sensor technology into industrial applications, an application laboratory is being established at Fraunhofer IAF. This will enable interested companies and especially regional SMEs and start-ups to evaluate the innovation potential of quantum sensors for their specific requirements. Both the state of Baden-Württemberg and the Fraunhofer-Gesellschaft are supporting the four-year project with one million euros each.

The application laboratory is being set up as part of the Fraunhofer lighthouse project »QMag«, short for quantum magnetometry. In this project, researchers...

Im Focus: How Cells Assemble Their Skeleton

Researchers study the formation of microtubules

Microtubules, filamentous structures within the cell, are required for many important processes, including cell division and intracellular transport. A...

Im Focus: World Premiere in Zurich: Machine keeps human livers alive for one week outside of the body

Researchers from the University Hospital Zurich, ETH Zurich, Wyss Zurich and the University of Zurich have developed a machine that repairs injured human livers and keep them alive outside the body for one week. This breakthrough may increase the number of available organs for transplantation saving many lives of patients with severe liver diseases or cancer.

Until now, livers could be stored safely outside the body for only a few hours. With the novel perfusion technology, livers - and even injured livers - can now...

Im Focus: SuperTIGER on its second prowl -- 130,000 feet above Antarctica

A balloon-borne scientific instrument designed to study the origin of cosmic rays is taking its second turn high above the continent of Antarctica three and a half weeks after its launch.

SuperTIGER (Super Trans-Iron Galactic Element Recorder) is designed to measure the rare, heavy elements in cosmic rays that hold clues about their origins...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

11th Advanced Battery Power Conference, March 24-25, 2020 in Münster/Germany

16.01.2020 | Event News

Laser Colloquium Hydrogen LKH2: fast and reliable fuel cell manufacturing

15.01.2020 | Event News

„Advanced Battery Power“- Conference, Contributions are welcome!

07.01.2020 | Event News

 
Latest News

A new 'cool' blue

17.01.2020 | Life Sciences

EU-project SONAR: Better batteries for electricity from renewable energy sources

17.01.2020 | Power and Electrical Engineering

Neuromuscular organoid: It’s contracting!

17.01.2020 | Life Sciences

VideoLinks
Science & Research
Overview of more VideoLinks >>>