ChemWeb Newsletter

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This week The Alchemist learns that boron most certainly is not boring, it now being a record-breaker in a chemical flat land. For medical science, we now have nanoparticles that shimmer and change color as a butterfly wing and in the world of bioanalysis, an easy to stick together microfluidic device for testing toxicity. Thermodynamics, we learn, could be crucial to the successful use of smart materials and memory alloys in making structures better equipped to resist earthquakes. In organometallic supramolecular chemistry a team in Germany has constructed a bronze Matryoshka from copper and tin cages. Finally, this week's award goes to British chemist Peter Bruce who is working on lithium-air batteries that could last up to thirty times as long as current technology without bulking up or gaining weight.

Alexander Boldyrev and colleagues at Utah State University, Logan, working with Lai-Sheng Wang and colleagues at Brown University in Providence, Rhode Island have synthesized a planar boron compound that has the highest coordination number of any flat molecule, squeezing ten spoke-like bonds to boron atoms into a wheel. This astounding feat of engineering not only breaks previous records for such compounds but offers new insights into bonding, coordination and the development of boron chemistry. Theoretical chemist Pekka Pyykkö of the University of Helsinki, Finland, is impressed. "At a deeper, quantum mechanical level, I find the electronic structure entirely logical and a pretty example on the eighteen-electron (18e) rule," he says.

Metallic nanoparticles that have some of the photonic characteristics of a butterfly's wing could be used as simple color-change components of a new approach to medical diagnostic tests, say researchers from Attophotonics Biosciences GmbH in Austria and at the University of Applied Sciences, in Wiener Neustadt. The team has demonstrated proof of principle for the detection of a model compound, interleukin-6 an important biomarker for acute sepsis. The sensitivity is high and the nanoparticles can readily be incorporated into a lab-on-a-chip device, the team reports.

Javier Atencia and colleagues at the US National Institute of Standards & Technology have taken a few sheets of plastic, a glass slide and some double-sided sticky tape to quickly and easily construct a lab-on-a-chip device for carrying out cell assays. Their "diffusion-based gradient generator" can be used to rapidly assess how changing concentrations of specific chemicals affect living cells. The microfluidic device could be used to carry out toxicity testing inexpensively on a range of chemicals.

Researchers at the Georgia Institute of Technology are investigating whether or not shape-memory alloys might be useful construction materials for seismic-resistant structures. Reginald DesRoches and colleagues have developed a computer model to study how these materials respond thermodynamically and mechanically to loading from strong motion. Their calculations could help determine the viability of using smart alloys made from combinations of copper-zinc-aluminum-nickel, copper-aluminum-nickel or nickel-titanium in cables, bars, plates and helical springs for engineering applications. For standard materials, mechanics is usually sufficient for engineers, but with smart materials thermodynamics becomes an important component of the equations.

As with the wooden Russian effigy of the maternal life cycle, the Matryoshka doll within a doll within a doll, a capsule of twelve copper atoms encases a single tin atom. But, the copper capsule is itself enveloped by 20 additional tin atoms. According to Thomas Faessler of the Technische Universitaet Muenchen, Germany, creator of the "bronze" Matryoshka, the substance itself is a rather unassuming fine, charcoal-gray powder. However, its nondescript appearance in the bulk belies the potential of these materials, with their large surface area to volume ratio, as catalysts for hydrogen transfer and other applications.

Chemist Peter Bruce of the University of St Andrew, UK, is to be honored with the inaugural UK Science Award by AkzoNobel for his fundamental research into rechargeable lithium batteries. Bruce's work might one day transform the driving range of electric vehicles and make renewable energy more viable. Lithium-air batteries have the potential to store up to 30 times the power of current lithium batteries. This could extend the distance electric vehicles might travel between charges considerably and nudge us towards greater adoption of carbon-free transport to cut pollution in cities and facilitate greater use of electricity generation based on renewable energy sources.