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This week, The Alchemist analyzes a potentially troublesome food additive, learns that there may well be water in the Moon, sheds light on transformations of porous coordination polymers, lines up quantum nanotubes, and unearths a nitric revelation. Finally, a communications award with a famous namesake.




A straightforward ultrasound extraction of food samples followed by flame atomic absorption spectrometry (FAAS) can be used to quickly determine concentrations of the potentially toxic flavor enhancer maltol, 3-hydroxy-2-methyl-4H-pyran-4-one. Maltol is present in coffee, baked cereals, bread crusts, and caramelized foods, and can made by sucrose pyrolysis or thermal degradation of starch. It was a useful additive but shows a dose-dependent toxicity mediated through programmed cell death, apoptosis, and the exposure is limited by World Health Organization (WHO) recommendations. The new analytical approach by scientists at the Cumhuriyet University, in Sivas, Turkey, could help inform regulators of problems with commercial food and beverages.





New evidence suggests that although there is no water on the Moon, there may well be water in the Moon. Satellite data analyzed a team at Brown University in Providence, Rhode Island, USA, demonstrates for the first time that water might be present within ancient explosive volcanic deposits on the Moon, suggesting that its interior contains substantial amounts of water. The key question now is whether or not those samples brought back by Apollo astronauts represent the bulk conditions of the lunar interior or an unusual or perhaps anomalous water-rich region within an otherwise "dry" lunar mantle,” explains lead author of the new research Ralph Milliken.





A light-responsive crystalline material the porosity of which changes when light shines on it has been developed by researchers at Kyoto University’s Institute for Integrated Cell-Material Sciences (iCeMS) and the University of Tokyo, Japan. Such materials might find applications in the development of photoresponsive materials controlled-release drug-delivery systems in dynamic tissue engineering scaffolds and other areas. The current system is based on a flexible porous crystal composed of a photoresponsive dithienylethene derivative, zinc ions, and 1,4-benenzenedicarboxylate which together form a porous coordination polymer.





Semiconducting carbon nanotubes can play host to light-matter quasi-partic¬les generated electrically within. Scientists Heidelberg University, Germany and the University of St Andrews, UK used light-emitting and extremely stable transistors to achieve strong light-matter coupling that produced exciton-polaritons. Such entities might be used in new light sources, such as electrically pumped polariton lasers. Because of the extreme stability and high conductivity, current densities and thus polariton densities are orders of magnitude higher than previously reported values for such systems, the team reports.





Back in the 1990s, nitric oxide was named "Molecule of the Year" because of the discovery of its role as a neurotransmitter and the understanding we gained from the discovery with regard to cardiovascular health and male sexual health. Textbooks were subsequently updated. Now a quarter of a century later, they might have to be written again thanks to a discovery by researchers at Cornell University, New York, USA. The work focuses on the nitrogen cycle rather than human physiology but could have global impact. The team has identified a critical step in the nitrification process, which is partly responsible for emissions of nitrous oxides into the atmosphere, which give agriculture a role in global climate change. Current biochemical models say that inorganic hydroxylamine is the only intermediate formed when bacteria convert ammonia from fertiliser into nitrite. But the new work suggests nitric oxide is a second intermediate in this process.





Mark Miodownik is this year's winner of the Royal Society's Michael Faraday medal and lecture for excellence in communicating science to UK audiences. Michael Faraday was perhaps one of the most famous scientists of the nineteenth century and well known for his public lectures, in particular his Christmas lectures for children at the Royal Institution. Miodownik, follows in Faraday's footsteps a popular communicator of science, one might say he could hold a candle to him...