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The Alchemist takes a look at phosphorus in soil this week and finds out how NMR might help manage agricultural levels of this element with a view to protecting waterways. We also hear how tubular soot, carbon nanotubes to you and me, might displace costly platinum from future fuel cells and so herald a new era in power supply. In physical chemistry new insights could explain why molten glass solidifies but retains the structure of a liquid, and in biochemistry, a new approach to producing glycoproteins could bring some regularity to biomedical research into these substances. In troubled times, airport security is high on the agenda and a new detector system for spotting secreted liquid explosives is emerging from the prototype stage. Finally, carbon dioxide is not all bad, research into its effects on wound healing has led to a significant prize for British scientists.




Sugar-modified proteins, glycoproteins, account for more than half of our body's protein roster as well as a wide range of pharmaceuticals. But, the natural glycoproteins tend to have a non-uniform sugar component, whereas for research applications it would be simpler and easier if they were more regular in nature. Now, Carlo Unverzagt at the University of Bayreuth, in Germany, and colleagues have used a new strategy to synthesize ribonuclease C (RNase C), a glycosylated bovine pancreatic enzyme, with a sugar "antenna". They used "native chemical ligation" to build the molecule rather than conventional solid-phase peptide synthesis. The approach will extend the use of RNase C as a model of glycoproteins.





Researchers at Los Alamos National Laboratory in New Mexico have developed a novel approach to testing for liquid explosives that could, in a few years, be used in homeland security. Stephen Surko of the Department of Homeland Security's Science & Technology Directorate (S&T) working with colleagues at LANL are investigating how to detect liquids in airline baggage and on passengers and to identify the liquid's constituents quickly and precisely. Their MagViz prototype machine uses a type of MRI spectroscopy to match sample spectra with the chemical fingerprints of 50 potentially hazardous liquids stored in a linked database. "Our vision for MagViz is that it would be operated in series with more traditional X-ray systems, and a conveyor belt would seamlessly move baggage or other items from one to the next," explains Surko.





The journal Medical Hypotheses has announced the winner of the 2008 David Horrobin Prize for medical theory. The journal has awarded Mikael Persson and Jan van der Linden of the Karolinska Institute in Sweden the award for their paper entitled "Intraoperative CO2 insufflation can decrease the risk of surgical site infection". The paper "best embodies the spirit of the journal" and represents an important development in the treatment of surgical wounds and the prevention of infection.





Phosphorus is a key nutrient, but can lead to toxic algal blooms and water-quality problems in lakes, rivers, and estuaries across the globe. It enters water from a variety of sources, including agriculture, both inorganic and manure-based farming practices. Improved understanding of phosphorus chemistry in soils is essential to allowing us to better manage and protect water quality. Now, a group of scientists in Australia and USA have used 31P NMR spectroscopy to characterise phosphorus in soils resulting from different long-term agricultural practices. "In terms of potential phosphorus loss in the long run, organic materials containing large amounts of phytate-P such as poultry manure may not differ from other material containing mainly inorganic P," team leader Zhengxia Dou explains.





One of the obstacles in the way of widespread adoption of fuel cell technology is the high cost of the precious metals needed for the catalytic membrane that allows the chemical energy input to be converted into an electrical output. Platinum is an exceptional material but very costly. Now, Liming Dai, the University of Dayton and colleagues have demonstrated that carbon nanotubes containing nitrogen are more effective, in the laboratory at least, and so could pave the way for a way to mass-produce fuel cells for a wide range of applications - from electric cars to domestic power plants - at much lower cost than is possible with platinum.





The transition from the melt to the solid phase can be simply explained by scientists, at least when discussing metals solidifying or liquid water freezing to ice. But, glass remains a mystery, why is amorphous silica a solid rather than a liquid at room temperature despite its structure? Now, researchers in the US and the UK believe they can begin to explain, at the atomic level, what happens when molten glass cools and hardens. Robert Jack at the University of Bath, England explains how he and his colleagues have focused on the ability or inability of "molecules" to flow and so have obtained evidence for a new kind of sudden transition between the flowing liquid and the solid glass.