ChemWeb Newsletter

Not a subscriber? Join now.January 26, 2012

special message from ChemWeb

At the ACS Fall Meeting in Denver.,CO, ChemWeb sponsored an iPad 2 raffle to promote new subscribers. We are happy to announce that Melissa McAlexander, an Assistant Professor in the Department of Natural Sciences at Notre Dame de Namur University in Belmont, California, is one of many new Alchemist subscribers, and our iPad 2 winner. Melissa teaches a wide range of courses including General Chemistry, Contemporary Environmental Issues, Microbiology Laboratory, and Immunology.


The Alchemist learns how to manipulate tiny polystyrene beads with a set of micro-tweezers this week and spots the smoking gun in forensics using capillary-scale ion chromatography and suppressed conductivity. In the world of chemophobia has asked why parabens are still the focus of research into underarm hygiene and breast cancer despite the lack of evidence linking the two in any way. There is also an elemental discovery this week concerning that lowliest of metals, zinc, which may have activity in reducing the symptoms of the common cold. A venture that sounds truly alchemical sees research into burning ice heating up. Finally, a prize teacher.

Tabloid scare stories and sensationalist emails concerning a wholly unproven link between parabens in underarm hygiene products and female breast cancer were bolstered again this month. A small study showed that of samples from 40 breast cancer patients all contained small quantities of these organic preservatives. The study did not analyse samples from non-patients as controls. Moreover, given that some of the women had never used underarm products yet still showed parabens in their samples suggests not that breast cancer is linked to these products but that they are simply ubiquitous. Epidemiological studies dating back to the early 2000s have shown no link and other studies have demonstrated that parabens are almost always present in urine samples tested.

Zinc has been The Alchemist's element of choice for warding off an imminent dose of the common cold, but is there any truth in the received wisdom that boosting intake of this trace element can stifle the worst symptoms of rhinovirus infection? It is unlikely that otherwise healthy individuals with a balanced diet who take regular exercise will be deficient in zinc. However, a Cochrane review of 15 randomized clinical trials suggests that taking zinc within 24 hours of the onset of symptoms can ameliorate the worst excesses of the body's response to a common cold and reduce the the number of days of misery.

A team at Pacific Northwest National Laboratory, PNNL, has carried out a computer analysis of gas hydrates to try and understand key details about their structure. The study is the first to accurately quantify the molecular-scale interactions between hydrogen or methane, the "natural" gas in the hydrates and the water molecules that form hydrogen-bonded molecular cages around them. The PNNL team demonstrated that hydrates can hold hydrogen at an optimal capacity of 5 mass percentage, which is considered a viable figure by the US Department of Energy making gas hydrates a practical and affordable alternative fuel source.

Organic chemist Brian Coppola of the University of Michigan is the recipient of the biannual Robert Foster Cherry Award for Great Teaching, which is given by Baylor University in Texas, in recognition of outstanding classroom teaching. The awards were established in 1991 to stimulate discussion in the academy about the value of teaching, and to encourage departments and institutions to value their own great teachers. It is named for 1929 Baylor graduate Robert Foster Cherry. Coppola receives $250,000 and his department $25,000. The U-M highlights its recent released payroll report, which cited Coppola's salary as $139,550 in 2011.

A set of micro-tweezers developed by scientists at Purdue University in West Lafayette, Indiana, could be used to build components for microelectromechanical systems (MEMS). Team leader Cagri Savran explains that the tweezers can be used to manipulate tiny polystyrene spheres and assemble them into three-dimensional structures. The device, which requires no electricity supply, comprises a "thimble" knob from a standard micrometer, a two-pronged tweezer made from silicon, and a "graphite interface," which converts the turning motion of the thimble knob into a pulling-and-pushing action to open and close the tweezer prongs. The same tweezers might also be used to handle spheres of stem cells or other biological entities and place them on to analytical devices or sensors.

Researchers in the UK have turned to capillary-scale ion chromatography and suppressed conductivity detection to develop a new method for the forensic analysis of gunshot residues, sweat and latent fingerprints. The application of statistical techniques allowed them to extract data to reveal whether fingerprints were left by someone who had recently discharged a firearm and even whether or not the suspect is a smoker. The scale of the technology required would enable portable forensic testing as well as being amenable to situations in which analysis of metallic content is not possible.