ChemWeb Newsletter

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The Alchemist asks this week whether NSAIDs are fit for purpose and discovers that topically they may well be, but only for a limited number of applications. Fluoridation is controversial health issue when it comes to teeth, but new research suggests its protective effect on dental enamel may not be so easily explained. In analytical chemistry, a new approach to oxygen sensors has been developed and in the criminal world, several chemists have become inadvertent inspiration for illicit syntheses. In Japan, researchers are brewing up hot toddies to improve their iron-based superconductors. Finally, chemists at Nottingham University famed for their video outreach have had a lot of fun with The Elements.




Non-steroidal anti-inflammatory drugs (NSAIDs) have a bad side effect profile; they can cause gastrointestinal bleeding and there are detrimental effects on the heart in some user. Now, evidence assessed in a new Cochrane Report suggests that in general oral NSAIDs cause more harm than good. Despite an early lack of evidence for efficacy of topical NSAIDs, more recent research suggests that for some uses, a topical treatment may be better in terms of risk-benefit ratio than an oral NSAID. Evidence is not strong for benefits in treating back pain, headache, or neuropathic pain, however.





The protective shield thought to be formed by fluoride on the surface of teeth could be less than a tenth the thickness that earlier research suggested. Fluoride in some toothpaste, mouthwash and municipal drinking water is one of the most effective ways to prevent tooth decay. However, research by Frank Mueller and colleagues at Saarland University in Saarbrucken, Germany, using X-ray photoelectron spectroscopy to analyze the depth and crystal structure of the films formed on teeth by fluoride confounds the theory that the film is a simple physical barrier. In research published recently in the journal Langmuir, the team suggests that the film of fluoridated hydroxyapatite thought to help protect teeth is so thin, at just 6 nanometers, that fluoride protection must arise through an alternative mechanism.





Sergey Borisov and his team at Graz University of Technology in Austria have developed strongly phosphorescent porphyrin complexes of iridium(III) that can act as optical oxygen-sensing materials. The amount of oxygen in living tissues accurately is a valuable tool in biomedical research, the team says, because it allows scientists to follow metabolic processes, spot anomalies and even detect diseased tissues. The use of these metal complexes highlights just how well they absorb and emit light, which makes them particularly good materials for optical sensor applications. While iridium complexes have been little studied previously, they do have the advantage of a broader absorption that is also shifted to lower wavelengths compared to platinum and palladium. The team adds that their sensor complexes can be tuned for particular applications. They demonstrated proof of principle with a water-soluble oxygen probe stained using bovine serum albumin and a trace oxygen sensor that is coupled to amino-modified silica gel.





There is growing concern among chemists involved in the synthesis and investigation of compounds with psychoactive and other properties that criminals are using their work to forward their own endeavors. Research into compounds that might become drugs of abuse is always likely to become a focus of those will malicious intentions. However, much of the research is aimed at improving organic synthetic chemistry for wholly legitimate reasons or for medicinal chemistry investigations into a wide range of diseases, including Parkinson's disease.





Japanese scientists have discovered that mulling their red wine with iron-based compounds can induce a state of superconductivity, the same effect occurs with sake and shochu, they claim. Iron-based compounds can be made to superconduct after exposure to the air, but the process usually takes, months; 24 hours in hot red wine is enough, the team from the Japanese National Institute for Materials Science says. The scientists are at a loss to explain why hot alcohol can speed up the process of converting an iron compound into a superconductor. However, it is known that iron-based compounds are readily magnetically ordered whereas in superconductivity, this magnetic order needs to be suppressed, elements present in the alcoholic drinks seem to be substituted into the iron compounds and so preclude magnetic ordering.





The Nottingham University team behind the Periodic Table of Videos, many of which have gone "viral" across the web and on social media, has put together an amusing take on the classic Tom Lehrer song, The Elements, which celebrates the chemist's favorite list. By splicing together clips from their dozens of prior videos, the team has fit a single mention of each element into the song, which sung to the tune of Gilbert & Sullivan's "A Modern Major General", recounts the periodic table as it was known to Lehrer back in 1959.