ChemWeb Newsletter

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The Alchemist Newsletter is back from a well deserved vacation and a move from London to Los Angeles. Now published by ChemIndustry, the newsletter and the ChemWeb site will continue to be offered as free services. We are working on some exciting new features for both ChemIndustry and ChemWeb and will notify our users by email in the weeks to come. Please contact the with your comments and suggestions.

In this second issue of the new Alchemist, David Bradley tucks into half a sandwich with catalytic potential and discovers how smart coated-glass could cut heating and air-conditioning bills. He also learns that the toxic structure of anthrax should lead to an antidote for this deadly agent within two years and digs in deep to report the chemical clues in earthquake prediction. Finally, Olympic athletes who have opted for chemical assistance in the form of human growth hormone are likely to be caught this year as a new test for the banned substance is to be implemented at the Games for the first time.

The first X-ray structure of a protein adduct of a half-sandwich ruthenium-arene complex could pave the way to a new class of hybrid catalyst. Peter Sadler and his team at the University of Edinburgh built adducts starting from various ruthenium complexes and the single chain protein lysozyme and carried out a crystallographic analysis that shows the resulting structure in fine detail. They explain that ruthenium arene binds selectively to the imidazole ring of the only histidine amino acid in the protein chain and results in the formation of a water-repelling, hydrophobic, binding pocket around the ruthenium. Such a site could provide the starting point for a new class of catalyst, explain the researchers. They add that ruthenium arene complexes also have anticancer activity so obtaining a clearer picture of their binding sites to proteins could provide new clues to how they work and perhaps lead to more effective derivatives.

Chemists at University College London have coated glass with an intelligent material that lets light through but impedes the flow of heat depending on the temperature. The coating is produced by atmospheric pressure chemical vapor deposition (CVD) of tungsten doped vanadium(IV) oxide from VOCl3, water and WCl6. The coated glass allows visible wavelengths of light through at all times but reflects infrared light when the temperature rises above 29°C. The change is due to an electronic rearrangement that switches the vanadium dioxide derivative between acting as a metal and a semiconductor. The UCL research team, led by Ivan Parkin, suggests that the coating's ability to switch between absorbing and reflecting means it could be used to allow the sun's heat to warm the occupants of buildings in cooler conditions. However, when temperatures soar room heating would be reduced by up to 50%.

Figuring out how the anthrax toxin enters cells could help researchers develop an effective antidote, according to a Californian team that has determined the crystal structure of the binding complex between anthrax toxin and one of its host receptors on our cells. The structure provides new insights into the biological action of anthrax, which can kill even once the microbe itself is dead. The researchers suggest that differences between the interaction of the anthrax toxin with this receptor and a second to which it also binds could be exploited in designing a novel antidote that would have little detrimental effect on healthy tissue. They suggest an antidote may be available within two years.

Changes in the earth's chemistry could help scientists predict earthquakes, according to researchers in Sweden. The method involves determining the concentration of iron, chromium, manganese, zinc, and copper. Alasdair Skelton of Stockholm University and his colleagues found a correlation between the levels of these metals in groundwater at a depth of 1.5 km before and after a major earthquake (5.8 on the Richter scale) that occurred in northern Iceland in September 2002. They monitored the concentrations ten weeks before and for one year after the earthquake and spotted chemical peaks at 10, 5, 2, and 1 week before the earthquake. The concentrations returned to normal levels after the earthquake. The researchers suggest that the dissolved metals migrate upwards from deeper in the earth entering the groundwater at about 1.5 km as the permeability of the earth's crust changes when an earthquake is imminent. Skelton suggests that the findings must now be confirmed for other earthquake prone regions of the world.

Four years of research at Southampton University, England, has led to the development of a new type of test for spotting illicit drug use in athletes, just in time for the 2004 Olympic Games in Athens. The test will be able to screen athletes for abuse of HGH, Human Growth Hormone abuse. HGH stimulates bone and muscle growth and has been the boost of choice for unscrupulous athletes and their trainers since the 1980s. It was finally banned by the International Olympic Committee in 1989. The test is completed in two parts taking urine and blood samples from random athletes within an hour of the end of each event. The first analysis will be done in Athens to demonstrate use of HGH in the prior 36 hours. The second analysis will be carried out in England and will reveal HGH use in the previous 84 days.