ChemWeb Newsletter

Not a subscriber? Join now.July 8, 2005

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This week in The Alchemist we take a look at a worrying trend as rising carbon dioxide turns the oceans acidic, we discover how an old treatment for jock itch could be useful in the fight against cancer, what makes anti-molecules unstable, and how ultrathin films could be used to pattern nanoscale devices. Finally, we learn that organic reactions can take place in water even if the reagents do not dissolve in that liquid.




What happens when matter meets antimatter? Theoretical scientists have addressed this issue by deriving the first analytical expression for the stability of matter-antimatter molecules. Dima Gridnev and Carsten Greiner of the Institute of Theoretical Physics, Frankfurt, Germany, looked at systems containing two positive particles and two negative particles that interact with each other through Coulombic forces. According to Gridnev, the hydrogen-antihydrogen molecule turns out to be unstable because the proton and antiproton approach each other too closely and are "seen" as a neutral combination by the other particles.





Penn State chemists have produced a new type of thin film that could allow chemists to build smaller electronic and sensing devices. According to Paul Weiss, monolayers with weak intermolecular interactions can act as placeholders for the intelligent self-assembly or directed assembly of molecular-scale structures. His team's 1-adamantanethiol on Au{111} layers can be exploited to enhance patterning in soft nanolithography. The layers have fewer defects than earlier monolayers and so could be used to accurately protect volatile or reactive surfaces and can then be removed easily before the next fabrication step is started. The researchers are currently attempting to exploit displacement in this manner.





Nobel chemist Barry Sharpless is about to revolutionize chemistry, or least that's what it seems. He and his team have discovered that they can carry out many organic reactions in pure water, even though the hydrophobic reagents do not actually dissolve in the polar solvent. There is a proviso - the water has to be very pure. But, they insist that is less of an obstacle to the "greening" of chemistry than finding ways to recycle, and ultimately dispose of, contaminated volatile organic solvents. The research suggests that even less noxious solvents such as supercritical fluids (SCFs) and room temperature ionic liquids (RTILs) may not be necessary to carry out reactions efficiently but with a lower environmental cost.





Increasing levels of pollution in the form of carbon dioxide could make the oceans more acidic and lead to damaging consequences for countless marine species, according to a report from the UK's Royal Society. The report claims that acidification due to the absorption of excess atmospheric carbon dioxide from the burning of fossil fuels has already increased acidity levels beyond the point at which they could be reversed in our lifetime. If emissions are not cut soon, however, acidity levels could continue to rise affecting the future survival of many species and ecosystems that cannot adapt to the changing conditions quickly enough.





A common treatment for athlete's foot and jock itch, griseofulvin, looks set to to make its debut as a new cancer treatment. Researchers at the Indian Institute of Technology Bombay and the University of California Santa Barbara, have tested the compound against cancer cell lines in the laboratory and found that it kills cancer cells via a similar mechanism as that responsible for the activity of paclitaxel and vinblastine - suppressing microtubule dynamics. The researchers suggest that a mild dose of griseofulvin could be used to bolster conventional anticancer drugs and so provide a therapeutic advantage for the treatment of certain tumors.