ChemWeb Newsletter

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An element close to every Alchemist's heart, quicksilver, or more properly mercury, featured in the chemistry news roundup this week, as does the creation of life from the primordial soup and how that may have begun. In the world of agrichemicals there is a possible sting in the tale for a relatively new class of pesticides, although no definitive evidence is yet available. In materials science tiny, but microscopic particles can undergo self-assembly it seems, while depressing news emerges from Europe regarding the lack of efficacy of an antidepressant drug marketed there. Finally, a new, free chemical dictionary is now available for word processors everywhere.




Laboratory simulations reveal the two-faced nature of how organic matter cycles toxic and less toxic mercury compounds in the environment. Microbial activity leads to formation of highly toxic methylmercury, but how the environment produces less toxic forms is less well understood. US researchers have now shown that compounds from the decay of organic matter in aquatic settings can affect mercury cycling. They demonstrated that low concentrations of these compounds can chemically reduce mercury, but as those concentrations increase, the process is greatly inhibited. This new understanding could one day lead to technology to address the global issue of mercury in global fish stocks and elsewhere.





Scientists do not know how the first living cells emerged from the so-called primordial soup, but new research suggests that photocatalysis of organic molecules in fatty acid membranes offers a plausible method for energy transfer and storage in prebiotic systems and perhaps explains how such vesicles might harness energy from their surroundings for chemical reactions. This would be an essential step on the road towards more complex systems and perhaps life. James Boncella and colleagues report a primitive energy transduction mechanism that demonstrates that photocatalytic reactions involving polycyclic aromatic hydrocarbons trapped in the vesicle membrane can capture and store energy.





There are growing concerns that a global problem known as colony collapse disorder, which is ravaging honeybee populations could be due partly to pesticide use. Various factors including climate change, ecosystem loss, viruses and fungi have been blamed for CCD over the last decade or so. But, environmental activists are pointing increasingly to neonicitinoid pesticides as causing changes in bee behavior leading to problems in the hive where larvae fail to thrive and a colony dies out. The debate is muddied by the fact that CCD has existed ever since humans have used honeybees if not before, while studies before these pesticides were widely used hinted at a pathogen carried by a bee mite being to blame. Leaked EPA documents and claims of conflicts of interest among researchers funded by the manufacturer Bayer have also made it difficult to extract the scientific facts from the politics.





A simple and general method for constructing complex structures using self-assemble has been developed by materials scientists at the University of Illinois. The work, involves tiny colloidal particles called triblock Janus spheres, and represents a significant step towards fabricating non-trivial, non-obvious structures from very simple building blocks, the developers say. "People know a lot about how to do [self-assembly] with molecules - soaps for example - but scientists and engineers know very little about how to make it happen with particles," team leader Steve Granick says. "Particles are very different from molecules, they're big, they're non-flexible, and they have lots of critically different materials properties." He adds that the approach might allow researchers in the future to mix together a soup of particles and fish out a designer computer chip. "Someday maybe we could have a soup of different components, remove some of it, and there would be a microelectronic chip," he explains. "It's a brand new area. The materials are so different that the structures that they form will be different."





Revelations from a German study regarding the alleged lack of efficacy and the potential for harm in people taking one antidepressant could reveal a critical flaw in the way these drugs are tested in animals. The antidepressant reboxetine (Edronax, Norebox, Prolift, Solvex, Davedax or Vestra) made by Pfizer is currently not approved by the US Food & Drug Administration for the US market but is prescribed elsewhere in the world. Now, a meta-analysis of studies suggests that efficacy is close to zero and that it may have very undesirable side-effects. According to Scientific American's correspondent, "the study [found] that reboxetine produced more side effects (noted as "adverse events") than placebo (as might be expected), but with no positive effects at all." Many antidepressants are not very effective, showing success in less than two-thirds of patients, but reboxetine is far less effective than that, the study suggests. In animals no serious adverse reactions were reported.





Version 3 of a free chemistry spellcheck dictionary for Word and OpenOffice has been released by its creator Adam Azman. The dictionary builds on earlier versions that used ChemSpider tools by crowd-sourcing common chemical terms that were missing from previous versions and incorporating user suggestions into this latest release. The dictionary is easily added to a word processor installation and makes spellchecking a chemistry document a much simpler and speedier process especially and precludes the need to add chemical names and words on an ad hoc basis, which many chemists and scientists in general do as they work on a document. The ease of installation and portability of the free dictionary means there is now no excuse for misspelling that compound name.