Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Edible Gas Storage

01.09.2010
Porous metal–organic framework made from food-grade natural products

A spoonful of sugar, a pinch of salt, and a splash of alcohol – those are the ingredients used by scientists to generate a new class of robust nanoporous metal–organic frameworks.

However, the sugar is not ordinary table sugar, but ã-cyclodextrin, produced from biorenewable cornstarch. As Fraser Stoddart and a team of scientists from Northwestern University in Evanston (IL, USA), the University of California in Los Angeles (USA), and the University of St. Andrews (UK) report in the journal Angewandte Chemie, this simple recipe could be the basis for a new class of biocompatible porous crystals made of renewable natural products.

Metal–organic frameworks (MOF) are well-ordered, lattice-like crystals. The nodes of the lattices are complexes of transition metals (such as copper, zinc, nickel, or cobalt); organic molecules make up the connections between the nodes. Within their pores, the MOFs can store gases such as hydrogen or carbon dioxide. Furthermore, they can be used for separation of materials, for catalysis, or for the targeted transport of drugs in the body. Most previously prepared MOFs are made of building blocks that stem from petrochemicals. Stoddart and his team set themselves a challenge to synthesize MOFs from natural products. “The problem is that natural building blocks are generally not symmetrical,” according to Stoddart, “this lack of symmetry seems to prevent them from crystallizing as highly ordered, porous frameworks.”

ã-Cyclodextrin provided the solution to this problem: it comprises eight asymmetrical glucose residues arranged in ring, which is itself symmetrical. In many countries (for example the USA and Japan), cyclodextrins are approved for use as food additives. The second ingredient in the frameworks is an alkali metal salt. Suitable candidates include ordinary table salt (sodium chloride), the common salt substitute potassium chloride, or potassium benzoate, an approved preservative. These ingredients are dissolved in water and then crystallized by vapor diffusion with an alcohol. It is even possible to use commercially available sources such as grain alcohol. “These ingredients are all substances that can be obtained cheaply, in high quality, and of food-grade purity,” says Stoddart.

The resulting crystals consist of cubes made from six ã-cyclodextrin molecules that are linked in three dimensions by potassium ions. These cubes are perfectly arranged to form a porous framework with easily accessible pores. “This arrangement is a previously unknown one,” says Stoddart. “The pore volume encompasses 54% of the solid body.” Particularly atypical of porous materials is the fact that when dissolved in water, the framework simply dissociates back to its components, which can then be crystallized again with alcohol. Says Stoddart: “In this way a degraded framework can easily be recycled or regenerated.”

Author: J. Fraser Stoddart, Northwestern University, Evanston (USA), http://stoddart.northwestern.edu/

Title: Metal-Organic Frameworks from Edible Natural Products

Angewandte Chemie International Edition, Permalink to the article: http://dx.doi.org/10.1002/anie.201002343

J. Fraser Stoddart | Angewandte Chemie
Further information:
http://stoddart.northwestern.edu/
http://pressroom.angewandte.org

More articles from Life Sciences:

nachricht CWRU researchers find a chemical solution to shrink digital data storage
22.06.2017 | Case Western Reserve University

nachricht Warming temperatures threaten sea turtles
22.06.2017 | Swansea University

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: Climate satellite: Tracking methane with robust laser technology

Heatwaves in the Arctic, longer periods of vegetation in Europe, severe floods in West Africa – starting in 2021, scientists want to explore the emissions of the greenhouse gas methane with the German-French satellite MERLIN. This is made possible by a new robust laser system of the Fraunhofer Institute for Laser Technology ILT in Aachen, which achieves unprecedented measurement accuracy.

Methane is primarily the result of the decomposition of organic matter. The gas has a 25 times greater warming potential than carbon dioxide, but is not as...

Im Focus: How protons move through a fuel cell

Hydrogen is regarded as the energy source of the future: It is produced with solar power and can be used to generate heat and electricity in fuel cells. Empa researchers have now succeeded in decoding the movement of hydrogen ions in crystals – a key step towards more efficient energy conversion in the hydrogen industry of tomorrow.

As charge carriers, electrons and ions play the leading role in electrochemical energy storage devices and converters such as batteries and fuel cells. Proton...

Im Focus: A unique data centre for cosmological simulations

Scientists from the Excellence Cluster Universe at the Ludwig-Maximilians-Universität Munich have establised "Cosmowebportal", a unique data centre for cosmological simulations located at the Leibniz Supercomputing Centre (LRZ) of the Bavarian Academy of Sciences. The complete results of a series of large hydrodynamical cosmological simulations are available, with data volumes typically exceeding several hundred terabytes. Scientists worldwide can interactively explore these complex simulations via a web interface and directly access the results.

With current telescopes, scientists can observe our Universe’s galaxies and galaxy clusters and their distribution along an invisible cosmic web. From the...

Im Focus: Scientists develop molecular thermometer for contactless measurement using infrared light

Temperature measurements possible even on the smallest scale / Molecular ruby for use in material sciences, biology, and medicine

Chemists at Johannes Gutenberg University Mainz (JGU) in cooperation with researchers of the German Federal Institute for Materials Research and Testing (BAM)...

Im Focus: Optoelectronic Inline Measurement – Accurate to the Nanometer

Germany counts high-precision manufacturing processes among its advantages as a location. It’s not just the aerospace and automotive industries that require almost waste-free, high-precision manufacturing to provide an efficient way of testing the shape and orientation tolerances of products. Since current inline measurement technology not yet provides the required accuracy, the Fraunhofer Institute for Laser Technology ILT is collaborating with four renowned industry partners in the INSPIRE project to develop inline sensors with a new accuracy class. Funded by the German Federal Ministry of Education and Research (BMBF), the project is scheduled to run until the end of 2019.

New Manufacturing Technologies for New Products

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Plants are networkers

19.06.2017 | Event News

Digital Survival Training for Executives

13.06.2017 | Event News

Global Learning Council Summit 2017

13.06.2017 | Event News

 
Latest News

Innovative LED High Power Light Source for UV

22.06.2017 | Physics and Astronomy

Mathematical confirmation: Rewiring financial networks reduces systemic risk

22.06.2017 | Business and Finance

Spin liquids − back to the roots

22.06.2017 | Physics and Astronomy

VideoLinks
B2B-VideoLinks
More VideoLinks >>>