ChemWeb Newsletter

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A nanocontainer and an elephant's tale catch is The Alchemist's all-seeing eye this week and appearing in the swirling mists - crystalline proteins, cannabinoids and bone, and walking water.




There is an obstacle to exploiting nanocontainers that might hold other molecules within - complex synthetic schemes. Now, Ralf Warmuth and colleagues at Rutgers University in New Jersey, USA, have produced an octahedral nanocontainer made up of eighteen distinct components that assembles itself in a single, elegant chemical reaction, removing the need for the usual long, complicated sequence of reactions. Their nanocontainer is big enough to trap small molecules and could be used as a novel catalyst, molecular sieve, or for pharmaceutical transportation.





Chemical analysis could help elephants and people live more harmoniously in countries such as Kenya where large free-roaming herds can wreak havoc on villages, livestock, and farmed crops. Researchers at the University of Utah analysed chemicals in elephant tail hair from those animals tagged with radio-GPS collars and so could track the diet and movements of the elephants across Kenya. Geochemist Thure Cerling and colleagues at the University of Utah determined the stable isotopes of carbon and nitrogen in African elephants' tail hair to help them correlate what the animals ate with where they ate it on the basis of GPS (Global Positioning System) data. Cerling says it is "important to quantify how much of elephants' diet comes from crops. It's going to help resolve elephant-human conflict by quantifying the crop damage done by elephants."





The bane of protein crystallographers is the common problem of proteins that simply will not crystallize; this is especially poignant when it comes to some of the more biomedically interesting of their number, such as the numerous membrane proteins, many of which do not succumb to even the most sophisticated crystallization techniques. Now, researchers at Imperial College London and the University of Surrey, both in the UK, have developed a new technique for crystallizing proteins, which could open up a whole range of materials to this powerful analytical technique. Naomi Chayen and colleagues have now successfully used porous BioGlass as novel nucleant to trap and encourage the growth of protein crystals. They found BioGlass induced the crystallisation of the largest number of proteins ever crystallised using a single nucleant, which could open up a whole new tranche of proteins to crystallographic studies.





A new approach to the debilitating bone loss disease osteoporosis could be on the horizon thanks to research by Andreas Zimmer and Meliha Karsak from the Bonn-based Life & Brain Center in Germany and collaborators in Israel, the UK, and the USA. The researchers have discovered a regulatory mechanism involved in bone loss linked to a chemical receptor in our bodies with a previously unknown function, which could lead to a new treatment. The team has now developed a new synthetic compound, HU-308, which activates CB2 and slows the development of osteoporosis in mice. This compound forms the basis for a cannabinoid-based, anti-osteoporotic type drug which has also been found to be free of any psychoactive side effects.





Droplets of water can "walk" uphill across a surface under their own steam according to Heiner Linke and his colleagues from the University of Oregon in Eugene. The self-propelled liquids could find use as a novel way to keep microprocessors cool and so allow them to run at higher speeds. To get droplets of water and other liquids to walk across a surface, the researchers etched a piece of brass with ratchet-like corrugations and then heated it to well above water's boiling point and exposed it to water. This produces a layer of water vapour, a Leiden frost layer, above the surface that allows a droplet of water to sit "on" the surface and to scoot across it with even the tiniest of applied forces.