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Buckyballs reach for the stars in this week's Alchemist chemistry news round-up while the oxygen levels in dead zones of the oceanic depths brings us back down to earth. An obvious contaminant explains why graphite oxides and related materials are wont to burst into flames and a prostate gel offers an improved diagnostic for a lethal disease. In the analytical arena, atomic absorption spectroscopy shows just how much iodine is present in a milk sample and could improve nutrition and nutritional studies. Finally, organic solar cells look set for a boost thanks to an NSF grant to aid their development over the next five years.




A simple, precise and accurate automatic technique based on indirect atomic absorption spectrometry can determine total iodine concentration in milk products and so might be used in improving quality control for infant formula milk, for instance, as well as in studies of this essential micronutrient. Researchers at the University of Santiago de Compostela, in Spain, have demonstrated iodine determination in the concentration range 0.011 to 0.35 micrograms per milliliter at a rate of seventeen samples per hour.





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.





Fullerenes were discovered in the early 1990s almost by accident when chemists were looking to explain diffuse spectral bands from cosmic dust. Now, the all-carbon soccerball molecules have truly gone extraterrestrial as Jan Cami of the University of Western Ontario, Canada, and colleagues have found evidence of gigantic clouds containing both C60 and C70 in the planetary nebula Tc 1, 6,000 light years from earth in the southern constellation Ara. Until now, the largest molecules identified had a mere 13 carbon atoms. The infrared spectrograph on NASA's Spitzer Space Telescope provided the data on Tc 1.





NASA recently published a worrying image showing the spread of oceanic dead zones across the globe. Now, researchers in Austria have for the first time shown how the behavior of marine creatures that live on the ocean floor can help us predict the development of these dead zones based on competition for oxygen. Regions of the oceans that lack the necessary oxygen concentration to sustain life are increasingly common, there are 400 known dead zones that have been recorded so far amounting to an area of ocean greater than 250,000 square kilometers, almost the area of the US state of Nevada. The causes are likely to be manifold: climate change, pollution, and other natural factors may be to blame. The researchers have built a catalog of animal behavioral models that are manifest when oxygen levels are lower than normal, which could be used to classify threatened marine environments.





Graphite oxide could be made a lot less flammable if a common contaminant were removed prior to use. Oxidizing and exfoliating graphite with concentrated acids and potent oxidizers such as potassium permanganate is well-known step in the production of the popular experimental material graphene. In contrast, graphene-type products made from graphite oxide - reduced graphite oxide and chemically modified graphene - are highly flame resistant. Now, while studying graphite oxide's exothermic properties, Northwestern University materials scientists Franklin Kim, Jiayan Luo, Jiaxing Huang, and colleagues have discovered that in the solid state, the material can undergo self-sustaining deoxygenation that propagates throughout the entire sample. Potassium salt residues are to blame the team has found.





A hydrogel capsule could improve diagnosis of prostate cancer, according to Japanese researchers. Itaru Hamachi and colleagues at Kyoto University, have developed a robust hydrogel that can selectively detect prostate cancer cells as well as releasing a fluorescent drug into those cells upon binding. The mode of action is based on cleavage of the hydrogel capsule by an enzyme produced only by the cancerous tissue. Prostate cancer is a slow-developing disease that remains symptom-free in the early stages. Current diagnostics are not considered entirely reliable. The hydrogel has advantages over conventional polymer capsules because it is biodegradable and so holds much greater promise as a potential diagnostic and drug delivery vehicle.