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Electrochemistry could be used in a new approach to detecting the spread of tumor cells in cancer patients, The Alchemist learns this week, while important clues about the impact of forest fires on the nitrogen cycle emerge from studies of charcoal and bacterial. In materials science, a bullet-proof material that behaves like a solid form of cornstarch and non-drip gloss paint emerges from Singapore research while electron transfer revealed by X-rays could explain solvent effects in the behavior of some proteins. News from the Gulf of Mexico turns out to be quite oily despite claims of clear waters. Finally, the American Chemical Society names almost 200 Fellows for 2010.




An electrochemical technique could quickly and easily differentiate between diseased and healthy tissue in cancer diagnosis, according to work by Japanese researchers. The method is based on the direct potentiometric measurement of the tumor marker, sialic acid, on cell surfaces. Certain types of cancer involve an overproduction of sialic acid in tumor cells, by binding this marker to phenylboronic acid added to a sample, the researchers can increase binding to an electrode and so detect the presence of cells with high levels of sialic acid by a change in electrode potential.





Researchers at the University of Montana have demonstrated that charcoal deposited during a forest fire has the potential to stimulate the conversion of ammonia to nitrates, which they point out is an important step in the nitrogen cycle. When fire razes a forest, nitrate levels rise and the effects can be persistent. Patrick Ball and colleagues have now found that a type of bacteria that transforms ammonia into nitrates are found in greater abundance in recently burned sites, despite the fact that the “recent” fire was twelve years prior to the sampling period. The research reveals a direct link between fire, charcoal, nitrification, and nitrifying microbes in coniferous forests of the inland Northwestern US.





A new impact-resistant composite material that is both flexible and lightweight has been developed by researchers in Singapore. The thixotropic material stiffens, in a similar way to cornstarch solution, when struck. A sheet of the new material just 20 mm thick is comparable in performance to hard ceramic or steel plates used as protective padding in ballistic vests. It could find use in replacing the thick, heavy steel plates worn by soldiers and law-enforcement officers beneath Kevlar body armor so improving mobility and comfort for the wearer.





X-ray absorption spectroscopy can be used to observe electron transfer, the movement of electric charges from solute to solvent, according to German researchers. The group at the Helmholtz-Zentrum Berlin für Materialien und Energie (HZB) used EXAFS of iron ions in both iron chloride and organic compounds such as hemin, the active center of hemoglobin to explain the hitherto inexplicable negative peak in its spectra. Measurements made using synchrotron light from the BESSY II X-ray source, allowed the team to show that certain solutes emit no fluorescent light after excitation because the radiationless return to the ground state takes place through a so-called "dark channel". The revelation could explain the contribution of solvent to the function of biochemical systems such as proteins.





The sudden "invisibility" of BP's oil spill in the Gulf of Mexico was widely reported in the media at the end of July, but the seeming absence of oil residues following the capping of the damaged oil well does not necessarily mean that chemistry, biology, and the weather have eradicated the problem. The National Oceanic and Atmospheric Administration stated that almost three fourths of the spilled oil has gone, either through capture, skimming, burning, evaporation, dissolution or dispersion, but that means that a fourth remains in the water and represents and ongoing threat to marine life and the coast.





Qiquan Qiao of South Dakota State University's Center for Advanced Photovoltaics is to receive $400,000 over the next five years to help in the development of less expensive and more efficient solar cells. The National Science Foundation CAREER award will help Qiao to develop organic photovoltaic materials, which he hopes could one day reach 10 to 15 percent efficiency. Specifically, Qiao will focus on novel polymers that have a long excited state lifetime.