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This week, The Alchemist hears that the "wonder" material of the modern age, graphene, might soon be used as a safe agent in medical imaging while pharma chemists are yet to boldly go anywhere very far in chemical space. A surprising discovery unravels nanoscopic coax cables for energy storage and green plastics as tough as steel might soon be possible. A natural mustard made by taily weed is another example of nature's chemical weapons. Finally, NMR spectroscopy just got easier to learn thanks to a coin flip game.

Researchers at Stony Brook University New York have developed a highly effective and potentially safer nanoparticle-based MRI (magnetic resonance imaging) contrast agent using the carbon allotrope graphene. There have been health concerns aired recently about the conventional gadolinium-based contrast agents used in medical imaging. Now, Balaji Sitharaman and colleagues have demonstrated how a graphene-based contrast agent could work at much lower dosages than standard contrast agents. The team also points out that their putative replacement is also a lot less expensive.

A new exploration of chemical space by Jean-Louis Reymond and Mahendra Awale suggests that drug researchers going as boldly as they might have barely even scratched the tip of the iceberg, to mix a metaphor, when it comes to synthesizing drug candidates. Writing in the journal ACS Chemical Neuroscience, the team suggests that the actual number of “small molecules” that might have physiological activity could number in the million billion billion billion billion billion billions (more than the number of stars in the universe, by one estimate). The Chemical Abstracts Service database lists a mere 67 million substances, less than a tenth of a percent of the chemical space suggested by the University of Berne team.

The serendipitous discovery by researchers at Rice University of a nanoscopic coaxial cable could lead to a new energy storage system. The same cable might also be used in lab-on-chip devices, microelectromechanical systems (MEMS). “At the outset, we were just curious to see what would happen electrically and mechanically if we took small copper wires known as interconnects and covered them with a thin layer of carbon,” explains study co-author Jun Lou. When Liu ran some electronic tests on his first few samples, the results were far from what he expected. The capacitance of the new nanocable is up to 143 microfarads per centimeter squared, better than the best previous results from microcapacitors.

Moshe Kol of Tel Aviv University, Israel, and colleagues are developing durable plastics to replace steel in many engineering applications. The team has developed a new catalyst for polypropylene production, which allows them to create the most regular form of the material yet possible with the highest melting point. "Everyone is using the same building blocks, so the key is to use different machinery," Kol explains. He suggests that the new tough plastics could be used to replace heavy steel components in cars and pipework in industrial facilities.

A desert plant has a neat way to coerce spiny mice in its native Negev Desert to spread its seed. The plant sweet mignonette, or taily weed, releases a toxic “mustard oil bomb” containing isothiocyanates when the mouse eats the plant's fruit making the critters spit out the seeds. The chemical weapon not only protects the plants' seeds from being ingested but any delay in the mouse reaction means that it allows the nocturnal rodents to spread the seed farther than they would otherwise reach if the fruit were simply to root at the foot of the parent plant. “It’s fascinating that these little mice are doing analytical chemistry, assaying the fruit for toxic compounds” and learning not to bite into the seed, explains team member Denise Dearing of the University of Utah. “It's not that these mice have poor table manners,” Dearing says. “They deliberately wiggle the seed out of the pulp of the fruit like a person does when eating watermelon. This removal of the seed keeps the toxins in the pulp from being activated.”

Ever the chemical information innovator, Adam Azman who teaches organic chemistry at Butler University has devised a "coin flip" game to help chemistry students get to grips with the concepts of nuclear magnetic resonance spectroscopy and more specifically the idea of coupling. By assigning a value to the head or tail when flipping two pennies, thousands of coin tosses will add or subtract from a tossed "quarter" - the "set of equivalent protons" giving a statistical 1:2:1 ratio of total values $0.23, $0.25, or $0.27. He points out that using a nickel will allow you to augment that game with J-values. You can play the game here -