The Alchemist Newsletter: July 25, 2007

The Alchemist learns that President Bush hands out the awards this week to several chemical scientists among others. A gecko-mussel mashup leads to a super but reversible adhesive that works under water and US scientists demonstrate that the pulsing of blood vessels might one day be used to power medical nanodevices and sensors. Also this week, great pond snails offer new channels to understanding how anesthetics knock you out and a novel hydrogel with antibiotic activity could lead to a new generation of wound-healing materials. Finally, theoretical insights into the behavior of a sodium cobalt oxide superconducting magnetic material could lead to the design of novel superconductors.

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Noble chemical laureate

President Bush recently announced the recipients of the 2005 and 2006 Medal of Science, America's highest honor for scientific achievement and among the laureates to receive the medal from the President on July 27 are Tobin Marks (Northwestern U, Evanston), Marvin Caruthers (Colorado U, Boulder), Peter Dervan (Caltech), Robert Langer (MIT), Lubert Stryer (Stanford U, Stanford), who all work in chemistry, chemical engineering, or biochemistry. The National Medal of Science was established by the 86th Congress in 1959 as a Presidential Award to be given to individuals "deserving of special recognition by reason of their outstanding contributions to knowledge in the physical, biological, mathematical, or engineering sciences."

President Bush Announces 2005 and 2006 Laureates of National Medals of Science and Technology

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Gecko and mussel mash

Did you hear the one about the gecko and the mussel? Well, they stuck together! A gecko's feet are like sticky notes, they adhere temporarily to most surfaces but can be pulled off again very quickly and then stuck again. Trouble is they don't work very well under water. Mussels, on the other foot, have evolved a biological adhesive that works incredibly well in water. Now, researchers at Northwestern University have made a biochemomechanical mashup of gecko and mussel stickiness to produce a temporary adhesive material that works even in water. Phillip Messersmith and graduate student Haeshin Lee reported the discovery of the new material, "geckel" in the journal Nature. The researchers imitated the gecko's foot by nanofabricating an array of silicone pillars and then coated them with a thin layer of synthetic polymer based on 3,4-L-dihydroxyphenylalanine (DOPA) to mimic the mussel adhesive protein. The invention could eventually have applications in medical, industrial, consumer and military settings, Messersmith says.

Synthetic Adhesive Mimics Sticking Powers of Gecko and Mussel

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Pulse-powered nano

A nanogenerator for powering implantable biomedical devices could tap off the energy of a heart beat or the pulsing of blood vessels, according to Zhong Lin Wang and colleagues at the Georgia Institute of Technology, Atlanta. Writing in the journal Nano Letters Wang explains that pulse-powered nano-devices could be used in biosensing, environmental monitoring and personal electronics. His team has built a prototype nanogenerator consisting of zinc oxide nanowires, which can convert mechanical energy into electricity. The latest version of their device produces 20-30 times greater current than the original prototype and works even when immersed in biological fluids. The device "sets a solid foundation for self-powering implantable and wireless nanodevices and nanosystems in biofluid and any other type of liquid," the researchers say.

Integrated Nanogenerators in Biofluid

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Pond snail anesthetic

A molecular link between the human brain and the nervous system of the great pond snail offers an important clue to help explain how anesthetics work. According to Nick Franks and colleagues at Imperial College London, have discovered a specific amino acid in neuronal potassium channels that when mutated inhibits the activity of anesthetics. Researchers have known of the importance of potassium channels in anesthesia for twenty years. Until the snail arrived, however, there has been no way to test the hypothesis directly. The next step will be to determine whether the same mutation in mice also makes them insusceptible to anesthesia. The work could ultimately lead to more effective anesthetics with fewer side effects than current compounds.

Scientists a step closer to understanding how anesthetics work in the brain

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Hydrogel skin repair

Chemistry could come to the rescue once again following serious wounding. Novel antibacterial hydrogels developed by Darrin Pochan and Joel Schneider of the University of Delaware, say the materials can be can be injected as a low-viscosity gel into a wound. Within the wound the gel hardens but not before it delivers a targeted payload of cells and antibiotics to repair the damaged tissue. Formulating hydrogels as delivery vehicles for cells extends the uses of these biopolymers far beyond soft-contact lenses into an intriguing realm once viewed as the domain of science fiction, including growing bones and organs to replace those that are diseased or injured, say the researchers.

Scientists Invent Novel Hydrogels for Repairing, Regenerating Human Tissue

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Electromagnetic connection

Theoreticians at the RIKEN Discovery Research Institute in Wako, and colleagues from the Universities of Chofu and Nagoya have shown that subtle fluctuations in electron spins are the origin of magnetism and superconductivity in sodium cobalt oxide. Their work contrasts with previous studies and demonstrates that both magnetism and superconductivity in the non-hydrated and hydrated forms of the oxide share a common origin. If proved experimentally, the discovery could lead to other superconducting materials with a so-called disconnected Fermi surface.

It's all in the spin

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-- David Bradley, Science Journalist