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The Alchemist this issue takes a look at colorful nanoparticles and how to control them with a magnet, a platinum wrap that could improve the efficacy of certain types of anticancer drug, an answer to why trucks cannot crush mother-of-pearl, and the chemistry behind plans for a liquid telescope destined for the moon. Also, this week, the discovery of a new type of electron wave that exists on metal surfaces could provide a new foundation for theoretical studies of chemical reactions. Finally, a princely sum is shared by the journals Nature and Science for excellence in science communication.




The top two general science journals - Nature and Science - have received a joint award for excellence in science communication from Spain's crown prince. The Prince of Asturias Foundation, formed in 1980 under the presidency of His Royal Highness, heir to the throne of Spain, honors scientific, technical, cultural, social and humanitarian work carried out internationally by individuals, groups or organizations, across eight categories. The award consists of a certificate, a sculpture especially designed for the Foundation by Joan Miró, and 50,000 Euros.





Yadong Yin and colleagues at the University of California, Riverside, have discovered that a simple magnet can be used to change the color of nanoparticles of iron oxide in aqueous suspension. The discovery could lead to a new class of low-power electronic displays. It also has the potential to be exploited in rewritable electronic paper and e-ink products. Yin explains that, "The key was to design the structure of superparamagnetic iron oxide nanoparticles through chemical synthesis so that they self-assemble into three-dimensionally ordered colloidal crystals in a magnetic field." Unlike certain other designer nanoparticle materials, such as coated gold particles, iron oxide is cheap, non-toxic and anything but rare.





Platinum-based anticancer drugs have been very successful in treating certain cancers, but medical researchers would like to extend their use more generally. The extremely potent drugs cisplatin, carboplatin, and oxaliplatin all lose activity on their journey from the site of administration to the target tumor. Now, chemist Stephen Lippard of Massachusetts Institute of Technology and colleagues have demonstrated that carbon nanotubes could be used as a novel delivery agent. The nanotube could protect the platinum drug from degradation until it is released at the tumor site.





Mother-of-pearl, or nacre, is commonly used in jewellery and for decoration, but its incredible strength and low density could be exploited in engineering applications if researchers could find a way to simulate it experimentally. Nacre lines the shells of sea creatures, such as oysters and abalones, is 3000 times stronger than the aragonite form of calcium carbonate from which it forms. Drive a truck over an abalone shell and the shell will be shattered but the nacre remain intact. Now, Pupa Gilbert of the University of Wisconsin-Madison, and her colleagues have used synchrotron radiation to reveal that nacre's secret could lie in the non-uniformity of its crystal structure. "If you understand how it forms, you could think of reproducing it, producing a synthetic material that's inspired by nature," Gilbert says.





A liquid reflector for a vast Newtonian telescope to be based on the surface of the Moon is being developed by scientists in Canada, UK, and US. The new type of telescope could provide the clearest views yet of ancient parts of the universe and will use a convex layer of an ionic liquid coated with silver. Earth-bound liquid reflectors have used mercury, but mercury would simply boil in the low-vacuum conditions on the Moon, moreover it would be dangerous and cumbersome to take to the Moon in the necessary quantities. An ionic liquid mirror the size of a football field on the Moon is not entirely implausible although the team led by Arizona scientist Roger Angel do not expect to be able to implement their plans until at least the year 2020.





Physicists at the University of New Hampshire have discovered a new type of electron wave that exists on metal surfaces. The work could have implications for research into nano-optics and high-temperature superconductors as well as providing new insights into the fundamentals of surface chemistry. "The existence of this wave means that the electrons on the surfaces of copper, iron, beryllium and other metals behave like water on a lake's surface,' says postdoctoral researcher Bogdan Diaconescu, 'When a stone is thrown into a lake, waves spread radially in all directions. A similar wave can be created by the electrons on a metal surface when they are disturbed, for instance, by light."