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This week The Alchemist hears about a physicist stirring up the theory of osmosis among biologists and chemists, about copper nanocatalysts with enormous potential in industry and a microbe detector that can shine a light on Staph. NASA is searching for biochemical happenings in the Titanic atmosphere, and a down to earth use for papyrus could help clean up Lake Victoria. Finally, chemists are taking the first steps towards a new kind of online assessment of their peers.




Osmosis is a lot more subtle than biologists and chemists think, a US physicist claims, moreover, he suggests explanations of the process in biology and chemistry textbooks perpetuate several myths. A range of surprising misconceptions about osmosis continue to appear in papers, web sites and textbooks, asserts Eric Kramer, of Bard College at Simon’s Rock in Great Barrington, Massachusetts. He suggests that many students learn this deceived wisdom and it wrongly influences their thinking throughout their careers. Kramer points out that osmosis applies to all fluids not just liquids, it does not require an attractive force, it does not always lead to dilution and finally there is a driving force, but it's due to the semi-permeable membrane not the fluids either side of it.





Engineers at the University of Michigan have demonstrated an environmentally friendly process for making propylene oxide based on copper nanoparticles, from which they can easily reverse surface oxidation to activate the catalyst using light. Suljo Linic and colleagues have shown how they can regenerate copper in metallic form with its unique electronic structure perfect for activating the reaction pathway from propylene to propylene oxide without boosting unwanted pathways. The secret is to form copper nanoparticles about 40 nanometers across and then to coat them with a dusting of silica. We are just scratching the surface, Linic says. I can envision many processes that wouldn't be possible with conventional strategies, where changing the oxidation state during the reaction or driving reactions with light could affect the outcome dramatically.





Scientists in the UK have developed a tool for quickly detecting the almost ubiquitous microbe Staphylococcus aureus, which is often present in devastating forms that are highly resistant to antibiotics. Adam Le Gresley, of Kingston University and colleagues use a fluorescent probe based on staphylothrombin, an enzyme found only in S. aureus. A test solution contains a tripeptide chain, which mimics staphylothrombin’s natural target and bound to the fluorescent dye rhodamine. If S. aureus is present in a sample, staphylothrombin will be released by the microbe which detaches the rhodamine from the tripeptide substrate leading to a strong color in the solution. The next step might be to modify the test so that it can distinguish between resistant and non-resistant forms of the microbe.





The organic chemistry on Saturn's moon Titan is likely to be rich, but could it harbor the building blocks of life? That's the question scientists at NASA's Jet Propulsion Laboratory, in Pasadena, California hope they might one day answer. The researchers have simulated the Titanic atmosphere and have found regions that could brew up the proverbial primordial soup. Scientists previously thought that as we got closer to the surface of Titan, the moon's atmospheric chemistry was basically inert and dull, explains JPL's Murthy Gudipati. Our experiment shows that's not true. The same kind of light that drives biological chemistry on Earth's surface could also drive chemistry on Titan, even though Titan receives far less light from the sun and is much colder.





Papyrus, perhaps best known as the earliest mobile medium for the written word (stone tablets being less portable), could have a new use in cleaning up waste water destined for tropical rivers and lakes. Robinson Odong and colleagues at Makerere University in Kampala, Uganda, have demonstrated that the papyrus sedge, a wetland grass can absorb otherwise toxic metals and organic compounds from slaughterhouse effluent that pours into the Nakivubo wetlands and ultimately reaches Lake Victoria. Growing large areas of this plant close to the outlets might improve water quality considerably. The same species could also be used for detoxifying effluents from other industries.





The emergence of web-enabled technologies, such as blogs over the last decade has gradually filtered into the world of chemistry, although long-time readers will know that ChemWeb has been around for even longer than that. One by-product of such developments is that researchers and those that follow their work are more able to react to each on a much shorter timescale than was possible in the print-only era. A relatively new blog, Blog Syn has been established as a forum on which organic chemists can discuss their attempts to reproduce each others' syntheses and in particular their failures. It has already generated controversy but is raising awareness of a more open lab book approach to chemistry.