ChemWeb Newsletter

Not a subscriber? Join now.October 24, 2006

contents
overview

This week The Alchemist visits the Sistine Chapel to discover how NMR could save Michaelangelo's famous frescoes from fading and reveals a gel that can stop bleeding within seconds. We also hear that elements 116 and 118 have been discovered (again), this time for real and how the musty smell produced when handling iron could have saved our ancestors' lives. Finally this week the a DNA computer that always wins at tic-tac-toe could be used to detect West Nile and avian influenza viruses.




Anyone who visits the Sistine Chapel in Rome cannot fail to be impressed by the results of a 20-year restoration project that has brought Michelangelo’s frescoes back to their original majesty. Most notable is the brilliance of the sky blue that almost illuminates the Last Judgment on the altar wall of the chapel. But, recent NMR analysis of the ultramarine pigment used to produce this stunning blue suggests its tendency to fade could see the Last Judgment and other works ultimately perish unless art conservationists act now. Alexej Jerschow of New York University, Eleonora Del Federico of the Pratt Institute, and their colleagues have used solid-state NMR to find out why this blue pigment fades. It appears that a break down of the pigments zeolite structure releases the sulfur-containing chromophores. Their findings could provide art conservationists with vital information how to protect works.





"We have found a way to stop bleeding in less than fifteen seconds, that could revolutionize bleeding control," that's the claim made by Rutledge Ellis-Behnke, a research scientist in the Department of Brain and Cognitive Sciences at Massachusetts Institute of Technology. He and his colleagues there and at Hong Kong University have investigated liquids, composed of peptides, and demonstrated that when applied to open wounds, the peptides self-assemble into a protective barrier gel that seals the wound and halts bleeding. As the wound heals, the non-toxic gel gradually breaks down into materials that cells can use to help in the repair. The international research team says their biocompatible material could address many problems facing hospital emergency rooms and operating theaters.





Researchers at the Livermore Lab, USA, and the Joint Institute for Nuclear Research (JINR) in Dubna, Russia have confirmed the fleeting existence of elements 116 and 118. These heavy elements were originally reported in 1999, by the Lawrence Berkeley National Laboratory but the claim was retracted when it was discovered some of the data had been falsified. The new evidence for element 118 and cousin 116 is more solid and pushes back the boundaries of the periodic table once more. The discovery should provide researchers with new insights into the nature of elemental instability. Element 118 is expected to be a noble gas that will sit nicely below radon in the periodic table. It has no official name yet, although for now you can call it ununoctium, or Uuo for short. Let's hope the powers that be allow the co-discoverers some poetic license in deciding on its final name.





The musty smell of iron when you handle it is a form of body odor, so say a team of researchers from the US and Germany. The reaction of oils in your skin with iron ions produces a variety of volatile organic compounds that produce the "musty metallic" smell. Dietmar Glindemann and his colleagues at the Virginia Polytechnic Institute and State University in the United States, the University of Leipzig, and the Leipzig Environmental Research Center also found that rubbing blood over skin results in a similar metallic smell formed from the same volatile molecules. They suggest that this "smell" of iron, is actually a way of sensing blood and could have helped our ancestors track wounded prey or find an injured fellow hunter.





A DNA computer could quickly and cheaply spot the telltale signs of pathogens such as West Nile and strains of the avian influenza virus, according to researchers Columbia University Medical Center in New York and the University of New Mexico, Albuquerque. Joanne Macdonald and her colleagues have developed the first "medium-scale integrated molecular circuit", which they say represents the most powerful DNA computing device to date. The MAYA-II (Molecular Array of YES and AND logic gates) can "compute" whether a particular viral strain is present in a blood sample or other fluid through molecular recognition of genetic information. The team has not yet optimized their DNA computer for diagnostics but they have demonstrated its prowess in tic-tac-toe as a proof of principle calculation.