ChemWeb Newsletter

Not a subscriber? Join now.August 25, 2010

contents
what's new on ChemWeb

The Events Calendar at ChemWeb.com lists conferences, seminars, trade shows, user group meetings, webinars and many other events of interest to ChemWeb members. The listings are free and they come from you - our members. We invite ChemWeb members to submit events to share with the ChemWeb community. Visit www.chemweb.com and click on *events* in the top navigation bar. To submit an event to the calendar, you should first login to the site and look for the *add item* link on the events page.



overview

Two years on, a simple color change test emerges from China for melamine in milk, The Alchemist learns. Also, with a Chinese connection, new insights into the mode of action of a former herbal remedy for fever could improve the outlook for malaria drugs. Materials news sees a thin film being stretched to double up its functionality, while applying pressure to another makes it a superconductor. Meanwhile, edible chemistry looks set to open up new applications for the pharma and food industries. Finally, a new way to chemicalize the world-wide web makes its debut online.




First, pets died in the US in 2007, then infants in China in 2008 succumbed to the scurrilous practice of artificially boosting protein readings in milk products by adding the nitrogen-rich industrial chemical melamine to milk products. There was a global outcry when the practice was exposed; 300,000 children were affected of which 6 died. Now, researchers in China have published details of a simple and effective color-change test for melamine contamination in such products. Details appear in the journal Talanta. Their colorimetric test uses gold nanoparticles to determine whether or not a product is tainted.





Understanding how the artemisinin works could help in efforts to create yet more effective drugs against malaria that are less prone to resistance. Artemisinin emerged from Chinese herbal medicine as a potential treatment for malaria and has proved itself efficacious in combination therapy. It was thought to work by forming heme-derived Fe(II) and C-centered radicals through its unusual peroxide lactone group. New research, however, suggests that the redox-active artemisinin molecule interferes with redox enzymes important for the malaria parasite through its ability to undergo both one-electron transfer and two-electron reduction processes. Several flavoenzymes are thought to be possible targets for follow-up drug research.





A thin film of europium titanate stretched across a dysprosium scandate substrate is the strongest simultaneously ferroelectric and ferromagnetic material made since the first, nickel boracites, were discovered in 1966. Materials that are at once ferroelectric and ferromagnetic could be useful in developing highly sensitive magnetic memory, magnetic sensors or microwave-based devices. The new material, discovered by a team at Cornell University, is one thousand times as powerful at 4 Kelvin, than its nickel predecessor, the team reports in the journal Nature recently. The new material, which exploits spin-lattice coupling, is at least 1000 times stronger than the nickel compound, and was synthesized based on theoretical studies to find an appropriate elemental combination.





Researchers at the Max Plank Institute for Solid State Research in Germany, working with colleagues in China and the USA have stumbled upon a way to induce a phase transition in a three-layered bismuth oxide crystal referred to as "Bi2223" to make it a superconductor under two different high pressures. The team suspects that this unusual two-step phenomena comes from competition of electronic behavior in different kinds of copper-oxygen layers in the crystal. The team hopes that this phenomenon might be exploited in creating superconductors that function under ambient conditions.





Metal organic frameworks (MOFs) hold much promise for catalysis and sensor applications, but can be expensive and difficult to synthesize. Now, a team in the US has used readily available and inexpensive materials, that just happen to also be edible, to construct a new class of MOF. Fraser Stoddart's team at Northwestern University in Illinois were experimenting with the starch-derivative cyclodextrin, when they crystallized something surprising - a solid with channels. The stable material persists even when solvent is removed from the channels and it is then capable of adsorbing nitrogen like other MOFs. Avoiding petrochemical derivatives as a starting material and turning to non-toxic substances could open up MOF research in the food and pharmaceutical industries.





A new way to view web pages that embeds chemical structures and generates property data on the fly has been released by the creators of the ChemAxon suite of chemistry software products. The tool is based at the free page - http://chemicalize.org - and allows users to see structures and data for compounds mentioned in any block of text or on a web page. The site is already gaining traction as a useful tool for users of the RSC's ChemSpider database of molecular structures but can be used anywhere to "chemicalize" information.