The Alchemist Newsletter: July 29, 2009

The Alchemist learns this week that music could be the key to the smooth running of a lab-on-a-chip, while tweaking quantum dots for the light show might be possible through physical rather than chemical changes. Imprinted polymers could remove vitamin B2 from beer giving it a longer-lasting flavor, we learn, while Japanese scientists have sniffed out the chemical basis of at least one form of aromatherapy. In the analytical arena, a simple enzyme-based test has been devised for spotting melamine adulteration in milk samples. Finally, the establishment of the InChI Trust will promote the use of chemical string theory for structure searching.

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Tuning up a lab-on-a-chip

Music could be the driving force behind a new approach to so-called lab-on-a-chip devices or microelectromechanical systems (MEMS). Rather than use complex electromechanical valves, a team at the University of Michigan Ann Arbor is using sound waves to drive a unique pneumatic system. Musical notes produce the required air pressure to control the movement of tiny droplets of sample through the device. The approach could make a reality of a device the size of an iPhone on to which you could sneeze and it would tell you if you have influenza, the researchers say. They don't discuss whether it would work best with classical tunes or heavy metal though.

Music is the engine of new U-M lab-on-a-chip device

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Nano light

It might be possible to tweak the optical properties of nanoparticles by changing their size as well as their chemical composition, according to a study by the National Renewable Energy Laboratory, Colorado. Alex Zunger and colleagues have used quantum mechanics to show how electron-hole exchange interactions in quantum dots depend on the size of the semiconductor material from which the dots are made and how the exchange interaction depends on the electronic structure of the quantum-dot semiconductor material. The result is important from a fundamental viewpoint because it reveals the origin of electron–hole exchange interactions and helps explain light emission in these materials on the nanoscale.

Understanding nanoscale light emission

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Booze on the shelf

Börje Sellergren, at the Technical University of Dortmund, Germany, and colleagues have synthesized an imprinted polymer that can remove riboflavin from milk, beer and multivitamin mixtures, and works well in water so doesn't require the use of toxic organic solvents. Riboflavin (vitamin B2) is responsible for driving photochemical oxidation in such products and so removing it should extend shelf-life considerably. A general approach for creating water-compatible molecularly imprinted polymers will open up many other similar applications in the food and drink industries.

The science of longer lasting lager

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A healthy smell

Akio Nakamura and colleagues at T. Hasegawa Co., Ltd in Kawasaki, Japan, claim to have demonstrated that inhaling linalool can reduce stress, in lab rats at least. They exposed the animals to stressful conditions and found that those inhaling linalool saw their stress-elevated levels of neutrophils and lymphocytes fall to near-normal levels compared with the controls. Inhaling linalool also reduced the activity of more than 100 genes that "go into overdrive" in stressful situations. The findings could form the basis of new blood tests for identifying fragrances that can soothe stress, the researchers claim. Linalool is present in the scent of lemon, mango, lavender, and various fragrant plants.

Stress Repression in Restrained Rats by (R)-(-)-Linalool Inhalation and Gene Expression Profiling of Their Whole Blood Cells

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Melamine blues

A simple, test kit for detecting melamine in liquids, including adulterated infant formula milk has been developed from enzyme research at the University of Minnesota. Until now, melamine testing required expensive laboratory equipment and skilled personnel. However, the MaxDiscovery Melamine Test kit can detect melamine in milk, powdered milk, cream, ice cream and chocolate drink through a simple visual reaction. The test uses melamine deaminase to release ammonia from the sample, which turns the liquid blue. The company marketing the kit, Bioo Scientific, is planning to adapt it to detect melamine in seafood and meat too.

University of Minnesota research leads to new technology to protect human health

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Inching towards trust

The InChI Trust was launched formally in July. The not-for-profit organization aims to expand and develop the InChI Open Source chemical structure representation algorithm. InChI was originally developed by the International Union of Pure and Applied Chemistry (IUPAC) and others to provide a simple string of alphanumeric characters to uniquely identify chemical structures so avoiding the need for complex two- or three-dimensional representations and so facilitating structure searching across databases and the web. The Trust was incorporated in the UK in May 2009 with six charter members: the Royal Society of Chemistry, Nature Publishing Group, FIZ-Chemie Berlin, Symyx Technologies, Taylor & Francis and OpenEye. Other members are now in the process of joining.

Launch of the InChI Trust

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-- David Bradley, Science Journalist