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Researchers at the Foundry Institute of the RWTH Aachen University in Germany, and Plant Biomechanics Group of the University of Freiburg, Germany, have taken inspiration from the hierarchical structure of the peel of the pomelo fruit (Citrus maxima) and have developed an aluminum hybrid that could be used to optimize technical components and safety materials. The new aluminum hybrid is the product of a bio-inspired approach, combining metals with different mechanical properties that reflect these naturally occurring structures and mimic the strength of the pomelo peel. The composite exhibits a much higher tensile strength (the force needed to break something apart) than pure aluminum, and a much higher ductility (the ability to withstand permanent changes in shape) than the aluminum-silicon alloy.





Working closely together, physicists from the Max Planck Institute for Nuclear Physics and chemists from Heidelberg University, Germany, have developed a method which can obtain a snapshot of a molecule's chirality, or handedness, an important property in pharmacology and biology. There are ways to get at chiral information available to chemists, but the new work allows them, for the first time, to determine absolute chirality of the molecules in a gaseous sample, in their experiments a chiral epoxide. The team obtains an image of the molecular structure by exploiting time-of-flight mass spectrometry and a Coulomb explosion.





Chad Mirkin of Northwestern University, USA, and his research team have used DNA and nanoparticles to build near-perfect single crystals for the first time, emulating the structures favored by nature. Single crystals are the backbone of many things we rely on - diamonds for beauty as well as industrial applications, sapphires for lasers and silicon for electronics, Mirkin. The quality and thus form and function depends on the material's precise atomic arrangement. Mirkin and his team suggest that they can now make precise crystalline nanomaterials. In the Northwestern study, strands of complementary DNA act as bonds between disordered gold nanoparticles, transforming them into an orderly crystal. The researchers determined that the ratio of the DNA linker's length to the size of the nanoparticle is critical. Our method could lead to novel technologies and even enable new industries, much as the ability to grow silicon in perfect crystalline arrangements made possible the multibillion-dollar semiconductor industry, he says.





Researchers at Umeå University in Sweden have demonstrated how the DNA polymerase epsilon enzyme builds new genomes. The detailed image they obtained using X-ray crystallography. The structure of the polymerase that we have solved makes it possible to see where these mutations lead to changes in the structure of DNA polymerase epsilon, explains Erik Johansson. This can help us to understand why a certain mutation contributes to the development of a certain cancer. Specifically, the new research shows how mutations that can contribute to the development of colorectal cancer and cervical cancer lead to changes in the structure of the protein.





Iron-based catalysts that side step the need for rare precious metals have been developed by researchers at the University of Toronto, Canada. Robert Morris and colleagues have replaced ruthenium, rhodium, palladium and platinum with iron in their novel catalysts for use in a wide range of reactions involved in the manufacture of pharmaceuticals, perfumes and other fine chemicals. There is a research effort world-wide to make chemical processes more sustainable and green, by replacing the rare, expensive and potentially toxic elements used in hydrogenation, catalytic converters in cars, fuel cells for the efficient conversion of chemical energy into electricity, and silicone coatings, with abundant ions such as iron, explains Morris. We found a way to make the ferrous form of iron behave in a catalytic process much more efficiently than a precious metal, he adds.





Researchers at the University of East Anglia (UEA), UK, are launching a new project to develop methods which could one-day decrease the use of rats and mice in pharmaceutical testing. They will receive backing from the National Centre for the Replacement, Refinement and Reduction of Animals in Research (NC3Rs) as part of its latest funding round. The development of a non-mammalian, pre-clinical screening tool for predictive analysis of drug safety will be carried out as a collaborative project between UEA's Grant Wheeler, Vicky Sherwood and Dominic Williams at the University of Liverpool. According to the UK government some 80,000 rodents were used in drug testing in 2012 in the UK alone. This is a huge number of animals, so any new protocols that can reduce this burden on animal testing could have a huge impact in significantly reducing the number of animals used for drug safety testing each year, says Wheeler. We aim to develop such a protocol using a combination of mammalian cell lines, early frog embryos and computer modelling to predict toxicity.