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This week, The Alchemist takes another look at an old friend, aspirin, that most venerable of pharmaceuticals. He also sheds light on catalysts and a silicon version of the carbon allotrope graphene. In the physical arena, splitting the electron is on the cards and a DNA triple helix comes to the fore in biology. Finally, an international award for a Chinese chemist.




Electrons are the currency of chemistry. The notion of their being divisible, however, has always piqued the interest of those scientists of a physical bent. Now, a team from Paul Scherrer Institute in Switzerland and IFW Dresden, Germany, claim to have split the electron and have experimental evidence and theoretical insights to support their results. Electron decay, the researchers say, produces two distinct parts - a spinon and an orbiton. The spinon carries the electron's spin and the orbiton its orbital moment. The new "particles" cannot escape the solid environment of strontium copper oxide in which they are formed by exposure to X-rays. Nevertheless, the finding may have implications for high-temperature superconductor research and in other fields, the team says.





We are familiar with the DNA double helix, less familiar is the entity that arises when three strands intertwine. However, a team at the Institute for Research in Biomedicine (IRB Barcelona) and the Barcelona Supercomputing Center (BSC) have obtained structural information for a triple helix DNA in a near-vacuum gas phase. "Until now these special DNA structures were almost impossible to detect," explains team leader Modesto Orozco. "We have characterized this structure and demonstrated that it maintains a surprising memory of its previous biological environment, aqueous solution, in which it is normally very difficult to characterize." The research could pave the way to developing antigen therapy in which triple-helical DNA is used to switch of genes in a particular disease state. The technique also shows how X-ray free-electron lasers are set to become powerful new tools for structural science.





Chemistry graduate student Shan Jiang was "overwhelmed with joy" to be named one of just 28 Outstanding Self-financed Chinese Students Studying Abroad in the UK, by the China Scholarship Council. The 27-year-old said: "I was very, very excited to receive an award in recognition of my PhD study and research. It's a great honor for me to actually have somebody out there who appreciates the hard work I have put into my research." Shan is working on a hot topic in modern chemistry, the development of porous organic cages for gas storage and gas separation.





An international research program has revealed once more that the earliest of commercial pharmaceuticals, aspirin, has yet more roles to play in medicine. The researchers have demonstrated that salicylate, the active metabolite, directly increases the activity of AMP-activated protein kinase. This enzyme is key player in the regulation of cell growth and metabolism and is, figuratively speaking, the cellular fuel-gauge. It is triggered by exercise and by the anti-diabetic medication metformin, so understanding and modulating its activity could be relevant to overweight, obesity and type 2 diabetes. "We show that salicylate increases fat burning and reduces liver fat in obese mice," says McMaster University's Greg Steinberg who is a principal investigator on the project.





Shedding light on enzymes can boost activity by up to thirty times, according to a study from Pratul Agarwal's team at Oak Ridge National Laboratory. The team introduced a light-activated molecular switch across two regions of the enzyme Candida antarctica lipase B, or CALB. This enzyme catalyzes the break down of lipids. "Using this approach, our preliminary work with CALB suggested that such a technique of introducing a compound that undergoes a light-inducible conformational change onto the surface of the protein could be used to manipulate enzyme reaction," Agarwal explains. This and related enzymes are widely used in industrial biotransformations to make biofuels and other compounds.





The silicon analog of graphene, dubbed silicene, might have potential in a wide range of electronics and engineering technologies, perhaps bridging the gap between conventional silicon semiconductor microcircuitry and the next generation of molecular and graphene-based electronics. Patrick Vogt of Berlin's Technical University, Germany, and Paola De Padova from the Istituto di Struttura della Materia in Italy criticize research that claims evidence of silicon monolayers akin to graphene. They have now used simple chemical vapor deposition techniques to grow a one atom-thick silicon layer on a silver crystal surface, and have strong evidence to support the production of silicone.