[Home]   [Full version]  

Unveiling the structure of microcrystals

Oct 04 ,Physics



Full size image
Microcrystals take the form of tiny grains resembling powder, which is extremely difficult to study. For the first time, researchers from the European Synchrotron Radiation Facility (ESRF) and the Centre National de Recherche Scientifique used X-ray diffraction at the synchrotron to determine the structure of microcrystal grains of one cubic micrometre. They gained a factor of a thousand on the size of the analysable samples, opening up new research possibilities to chemists, physicists and biologists.

The properties of a crystal are determined by the arrangement of its atom in space, its crystalline structure. Scientists use X-ray or neutron diffraction to study crystalline structure when the size of the crystal is more than 10 cubic micrometres. Below this limit, the solid material is considered a powder.

Scientists can apply powder diffraction to analyse such a material but this technique is not easy to exploit. Moreover, powder diffraction can only be used for materials with grain sizes of less than three millionths of a cubic micrometre. Due to these limitations, a determination of the structure of new synthetic solids in powder form is not always possible because the crystals are too small.

The teams from the ESRF and the Institute Lavoisier (CNRS/Université de Versailles Saint-Quentin) have used new set-up permitting X-ray diffraction on crystals of a size of one cubic micrometre, a volume a thousand times smaller than that ever attainable before. This new set-up consists of a focussing system for the ESRF beam, coupled with a goniometer, an instrument to position the sample with maximum precision.

The researchers studied the structure of an organic-inorganic hybrid compound (a microporous aluminium carboxylate), which could be used for gas absorption or to encapsulate various organic molecules. This study confirms that the new set-up allows pushing back the limits in crystal dimension accessible to X-ray diffraction.

“It is a revolution: what was considered a powder in the past has become a crystal today. Researchers can now bring forward samples left in their cupboards because the sizes had previously prevented their study. Now they will be able to elucidate the structures of these samples, with potentially great scientific advances on the horizon”, explains Thierry Loiseau, from the Institut Lavoisier.

Source: European Synchrotron Radiation Facility

Related stories:

Crystal clear savings for drug giants
Drug companies could save millions thanks to a new technology to monitor crystals as they form. The technique, developed by University of Leeds engineers, is a potentially invaluable tool in drug manufacture, where controlling crystal forms is crucial both to cost and product safety.
Researchers mimic bacteria to produce magnetic nanoparticles
When it comes to designing something, it’s hard to find a better source of inspiration than Mother Nature. Using that principle, a diverse, interdisciplinary group of researchers at the U.S. Department of Energy’s Ames Laboratory is mimicking bacteria to synthesize magnetic nanoparticles that could be used for drug targeting and delivery, in magnetic inks and high-density memory devices, or as magnetic seals in motors.
Powders show their strength
[PIC=:left]Growing a single crystal of a protein can be very difficult. Thanks to recent developments, a powder sample may be enough to solve a structure.
University of Pennsylvania engineers discover natural 'workbench' for nanoscale construction
Engineers at the University of Pennsylvania have taken a step toward simplifying the creation of nanostructures by identifying the first inorganic material to phase separate with near-perfect order at the nanometer scale. The finding provides an atomically tuneable nanocomposite “workbench” that is cheap and easy to produce and provides a super-lattice foundation potentially suitable for building nanostructures.
Innovation in Nanoporous Chemistry
Science researchers from the University of Versailles (France), in collaboration with the ID31 beam line at the European Synchrotron Radiation Facility (ESRF), report their progress in the design and characterisation of microporous materials.
Unlocking hydrogen's fuel potential
Hydrogen is being touted as the fuel of the future, a clean-burning, renewable and inexpensive replacement for petroleum. But a major stumbling block for hydrogen-powered vehicles is figuring out a way to carry enough hydrogen onboard to travel even moderate distances between refueling stops.
Researchers study how to make nanomaterial industry environmentally sustainable
Research into making the emerging nanomaterial industry environmentally sustainable is showing promise in a preliminary engineering study conducted at the Georgia Institute of Technology and Rice University.
Under the auspices of the Rice University Center for Biological and Environmental Nanotechnology (CBEN) funded by the National Science Foundation (NSF), researchers have been investigating the potential environmental impact of nanomaterial waste. Specifically, they want to know if they can predict the fate and transport of nanomaterial waste in natural systems, and whether nanomaterials will behave the same as common environmental pollutants. In addition, they want to determine if nanomaterials can be treated before they enter the environment to minimize impact.
Structure of chocolate unravelled by synchrotron radiation
Think about a piece of chocolate. Imagine it melting in your mouth. The sensation is delicious. Now think of the same image, but this time the chocolate is covered by a white film on its surface. This white film is produced when chocolate is poorly crystallised or when it is stored under the wrong conditions. We ’eat’ also with our eyes, so such bad-looking chocolate seems less nice to the palate. Here is where scientists come into the picture. Researchers from The Netherlands working at the ESRF try to avoid this white layer, called fat bloom, by studying the structure of chocolate. Their aim is to optimise the pleasure of eating it. They publish this week in the Journal of Physical Chemistry B the structure of a component of cocoa butter and also the crystal structure of the most common form of cocoa butter in chocolate, a result that is of great importance for chocolate production. The ESRF synchrotron light was essential for this research.

News discussion:

Physics news

[Home]   [Full version]