Nav: Home

New microscopy method for quick and reliable 3-D imaging of curvilinear nanostructures

September 06, 2017

Physical and biological sciences increasingly require the ability to observe nano-sized objects. This can be accomplished with transmission electron microscopy (TEM), which is generally limited to 2D images. Using TEM to reconstruct 3D images instead usually requires tilting the sample through an arc to image hundreds of views of it and needs sophisticated image processing to reconstruct their 3D shape, creating a number of problems. Now, EPFL scientists have developed a scanning transmission electron microscopy (STEM) method that generates fast and reliable 3D images of curvilinear structures from a single sample orientation. The work is published in Scientific Reports.

The labs of Cécile Hébert and Pascal Fua at EPFL have developed an electron microscopy method that can obtain 3D images of complex curvilinear structures without needing to tilt the sample. The technique, developed by EPFL researcher Emad Oveisi, relies on a variation of TEM called scanning TEM (STEM), where a focused beam of electrons scans across the sample.

The novelty of the method is that it can acquire images in a single shot, which opens the way to study samples dynamically as they change over time. Furthermore, it can rapidly provide a "sense" of three dimensions, just like we would have with a 3D cinema.

"Our own eyes can see 3D representations of an object by combining two different perspectives of it, but the brain still has to complement the visual information with its previous knowledge of the shape of certain objects," says Hébert. "But in some cases with TEM we know something about what shape the sample's structure must have. For example, it can be curvilinear, like DNA or the mysterious defects that we call 'dislocations', which govern the optoelectronic or mechanical properties of materials."

The classical approach

TEM is a very powerful technique that can provide high-resolution views of objects just a few nanometers across -- for example, a virus, or a crystal defect. However TEM only provides 2D images, which are not enough for identifying the 3D morphology of the sample, which often limits research. A way around this problem is to acquire consecutive images while rotating the specimen through a tilt arc. The images can then be reconstructed on a computer to gain a 3D representation of the sample.

The problem with this approach is that it requires extreme precision on hundreds of images, which is hard to achieve. The 3D images generated in this way are also prone to artefacts, which are difficult to remove afterwards. Finally, taking multiple images with TEM requires shooting a beam of electrons though the sample each time, and the total dose can actually affect the sample's structure during acquisition and produce a false or corrupted image.

The new approach

In the STEM method developed by the researchers, the sample stands still while the microscope sends two beams of electrons tilted against each other, and two detectors are simultaneously used to record the signal. As a result, the process is much faster than previous TEM 3D imaging technique and with almost no artefacts.

The team also used a sophisticated image-processing algorithm, developed in collaboration with Fua's CVlab, to reduce the number of images needed for 3D reconstruction to only two images taken at different electron beam angles. This increases the efficiency of data acquisition and 3D reconstruction by one to two orders of magnitude compared to conventional TEM 3D techniques. At the same time, it prevents structural changes on the sample due to high electron doses.

Because of its speed and immunity to problems with standard TEM methods, this "tilt-less 3D electron imaging" method is of great advantage for studying radiation-sensitive, polycrystalline, or magnetic materials. And because the total electron dose is reduced to a single scan, the method is expected to open up new avenues for real-time 3D electron imaging of dynamic material and biological processes.
-end-
Funding

Swiss National Science Foundation

Reference

Emad Oveisi, Antoine Letouzey, Duncan T.L. Alexander, Quentin Jeangros, Robin Schäublin, Guillaume Lucas, Pascal Fua, Cécile Hébert. Tilt-less 3-D electron imaging and reconstruction of complex curvilinear structures. Scientific Reports, 06 September 2017. DOI: 10.1038/s41598-017-07537-6

Ecole Polytechnique Fédérale de Lausanne

Related Electrons Articles:

Deceleration of runaway electrons paves the way for fusion power
Fusion power has the potential to provide clean and safe energy that is free from carbon dioxide emissions.
Shining light on low-energy electrons
The classic method for studying how electrons interact with matter is by analyzing their scattering through thin layers of a known substance.
Ultrafast nanophotonics: Turmoil in sluggish electrons' existence
An international team of physicists has monitored the scattering behavior of electrons in a non-conducting material in real-time.
NASA mission uncovers a dance of electrons in space
NASA's MMS mission studies how electrons spiral and dive around the planet in a complex dance dictated by the magnetic and electric fields, and a new study revealed a bizarre new type of motion exhibited by these electrons.
'Hot' electrons don't mind the gap
Rice University scientists discover that 'hot' electrons can create a photovoltage about a thousand times larger than ordinary temperature differences in nanoscale gaps in gold wires.
Electrons used to control ultrashort laser pulses
We may soon get better insight into the microcosm and the world of electrons.
Supercool electrons
Study of electron movement on helium may impact the future of quantum computing.
Two electrons go on a quantum walk and end up in a qudit
There is a variety of physical systems that can be used to implement a separate quantum bit, but significantly less research has been done into systems of several qubits or qudits.
Radiation that knocks electrons out and down, one after another
Researchers at Japan's Tohoku University are investigating novel ways by which electrons are knocked out of matter.
Controlling electrons in time and space
A new method has been developed to control electrons being emitted from metal tips.

Related Electrons Reading:

The Electron
by Dennis Morris (Author)

This book presents the modern quantum field theory view of the electron. This view is very different from the outdated classical view that is most often taught in schools and colleges. We cannot present the QFT view of the electron without also presenting the electron's sister particle the neutrino, and so the QFT view of the neutrino is presented also. The quantum physics equations which describe the electron and the neutrino are presented in a simple and clear way. The Dirac equation is rewritten using quaternions, and this leads to a resolution of the neutrino mass problem and to an... View Details


There Are No Electrons: Electronics for Earthlings
by Kenn Amdahl (Author)

An off-beat introduction to the workings of electricity for people who wish Richard Brautigan and Kurt Vonnegut had teamed up to explain inductance and capacitance to them. Despite its title, it's not wild ranting pseudo-science to be dismissed by those with brains. Rather, Amdahl maintains that one need not understand quantum physics to grasp how electricity works in practical applications. To understand your toaster or your fax machine, it doesn't really matter whether there are electrons or not, and it's a lot easier and more fun to start with the toaster than with quarks and calculus. The... View Details


Pushing Electrons
by Daniel P. Weeks (Author)

This brief guidebook assists you in mastering the difficult concept of pushing electrons that is vital to your success in Organic Chemistry. With an investment of only 12 to 16 hours of self-study you can have a better understanding of how to write resonance structures and will become comfortable with bond-making and bond-breaking steps in organic mechanisms. A paper-on-pencil approach uses active involvement and repetition to teach you to properly push electrons to generate resonance structures and write organic mechanisms with a minimum of memorization. Compatible with any organic chemistry... View Details


Electron: From Beginner to Pro: Learn to Build Cross Platform Desktop Apps using Github's Electron
by Chris Griffith (Author), Leif Wells (Author)

Discover how to take your existing web development skills and learn how to create desktop applications for macOS, Windows, and Linux, using GitHub's Electron. Learn how to combine the power of Node.js and Chromium to provide a powerful development platform for creating web applications that break free from the browser.

Electron: From Beginner to Pro guides you through the capabilities that you have available to create desktop applications. Learn to use features like file system access, create native menus, OS-specific dialogs and more. The authors will show you how to package... View Details


My First Science Textbook: Electrons
by Mary Wissinger (Author), Genius Games (Contributor), John Coveyou (Contributor), Harriet Kim Anh Rodis (Contributor)

Spark scientific curiosity in kids of all ages! Even a toddler can begin to understand the basics of chemistry as they follow Pete the Proton, Ned the Neutron and Ellie the Electron who get together to build everything in the universe. And the science is introduced in a way that's highly memorable, highly educational and funny too! "My First Science Textbook" is a series, of children's science books that teach kids the basics the of chemistry using simple rhyming sentences and vibrantly colorful science pictures that make it easy for young kids to engage and understand. In this Book 2 of a... View Details


Pushing Electrons: A Guide for Students of Organic Chemistry
by Daniel P. Weeks (Author)

SpartanModel replaces the plastic models used by past generations of organic chemistry students. This set of easy-to-use digital builders allows you to construct and manipulate 3-D molecules of any size or complexity.
View Details


Three-Dimensional Electron Microscopy of Macromolecular Assemblies: Visualization of Biological Molecules in Their Native State
by Joachim Frank (Author)

Cryoelectron microscopy of biological molecules is among the hottest growth areas in biophysics and structural biology at present, and Frank is arguably the most distinguished practitioner of this art. CryoEM is likely over the next few years to take over much of the structural approaches currently requiring X-ray crystallography, because one can now get good and finely detailed images of single molecules down to as little as 200,000 MW, covering a substantial share of the molecules of greatest biomedical research interest. This book, the successor to an earlier work published in 1996 with... View Details


My First Science Textbook: Atoms
by Mary Wissinger (Author), Genius Games (Contributor), John Coveyou (Contributor), Harriet Kim Anh Rodis (Contributor)

Spark scientific curiosity in kids of all ages! Even a toddler can begin to understand the basics of chemistry as they follow Pete the Proton, Ned the Neutron and Ellie the Electron! And the science is introduced in a way that's highly memorable, highly educational and funny too! "My First Science Textbook" is a series, of children's science books that teach kids the basics the of chemistry using simple rhyming sentences and vibrantly colorful science pictures that make it easy for young kids to engage and understand. In this Book 3 of a three book series, Pete the Proton, Ned the Neutron and... View Details


Scanning Electron Microscopy and X-ray Microanalysis: Third Edition
by Joseph Goldstein (Author), Dale E. Newbury (Author), David C. Joy (Author), Charles E. Lyman (Author), Patrick Echlin (Author), Eric Lifshin (Author), Linda Sawyer (Author), J.R. Michael (Author)

This text provides students as well as practitioners with a comprehensive introduction to the field of scanning electron microscopy (SEM) and X-ray microanalysis. The authors emphasize the practical aspects of the techniques described. Topics discussed include user-controlled functions of scanning electron microscopes and x-ray spectrometers and the use of x-rays for qualitative and quantitative analysis. Separate chapters cover SEM sample preparation methods for hard materials, polymers, and biological specimens. In addition techniques for the elimination of charging in non-conducting... View Details


Transmission Electron Microscopy: A Textbook for Materials Science (4 Vol set)
by David B. Williams (Author), C. Barry Carter (Author)

This profusely illustrated text on Transmission Electron Microscopy provides the necessary instructions for successful hands-on application of this versatile materials characterization technique. The new edition also includes an extensive collection of questions for the student, providing approximately 800 self-assessment questions and over 400 questions suitable for homework assignment.

View Details

Best Science Podcasts 2017

We have hand picked the best science podcasts for 2017. Sit back and enjoy new science podcasts updated daily from your favorite science news services and scientists.
Now Playing: TED Radio Hour

Simple Solutions
Sometimes, the best solutions to complex problems are simple. But simple doesn't always mean easy. This hour, TED speakers describe the innovation and hard work that goes into achieving simplicity. Guests include designer Mileha Soneji, chef Sam Kass, sleep researcher Wendy Troxel, public health advocate Myriam Sidibe, and engineer Amos Winter.
Now Playing: Science for the People

#448 Pavlov (Rebroadcast)
This week, we're learning about the life and work of a groundbreaking physiologist whose work on learning and instinct is familiar worldwide, and almost universally misunderstood. We'll spend the hour with Daniel Todes, Ph.D, Professor of History of Medicine at The Johns Hopkins University, discussing his book "Ivan Pavlov: A Russian Life in Science."