A candidate of choice is formic acid: it is a small molecule, solid at ambient conditions, that can easily be converted to hydrogen (and carbon dioxide as a side-product). Alternatively, hydrogen (from renewable sources) and carbon dioxide can be combined to generate formic acid. However, the formation or decomposition of formic acid are not spontaneous, and catalysts are required in order for these reactions to proceed at useful rates.

In this context, a new catalyst was developed by Albert Boddien et al. from the Leibniz-Institut für Katalyse in Rostock, Germany, that can efficiently liberate hydrogen from formic acid. Importantly, the catalytic system, reported recently in Science, involved the use of an iron salt and a phosphine dissolved in propylene carbonate. The process is remarkable since it avoids the use of expensive, rare metals or highly toxic solvents – in addition to evolving hydrogen with high efficacy. Mechanistic investigations were performed based on nuclear magnetic resonance spectroscopy, kinetic studies, and density functional theory calculations to explain possible reaction mechanisms.

The catalytic cycle involving formic acid (HCOOH). The catalyst presented in the mentioned article is indicated here as 'catalyst B'.

This work represents an important step towards the use of formic acid as a safe, user-friendly surrogate for hydrogen in the frame of renewable energies.

A team led by Prof. Jennifer Helisseeff at Johns Hopkins University recently presented a novel implant, that can be injected as a liquid under the skin, then modeled to appropriate shape, and solidified by exposure to light. The composite material is made by mixing polyethylene glycol (PEG), a widely used artificial polymer, with hyaluronic acid, a natural polysaccharide. The ratio of PEG and hyaluronic acid can be tuned, such as to modulate the properties of the final polymer: it can then be adapted to the location where the injection takes place (fat, muscle, skin). After injection under the skin (tests were made on rodents and with human patients), the implants could be massaged into shape. Finally, exposure to visible light initiated a cross-linking reaction between the PEG molecules, transforming the implant into a solid, shape-persistent hydrogel with entrapped hyaluronic acid molecules.

Although the newly-develped implants possess good longevity and stability, it was found that they cause more inflammation than currently used implants. However, the presented technique will probably find numerous application in reconstructive surgery, as soon as the last problems will have been sorted out.

The liquid polymer is injected, and solidified by irradiation.

Reference: A. T. Hillel et al., Sci. Trans. Med. 2011, 3, 93ra67. DOI: 10.1126/scitranslmed.3002331

No better illustration of the dual character of virtually any substance can be found than this report recently appeared in the FASEB journal. A team of researchers from Paris led by Patrick P. Michel investigated the beneficial effects of nicotine for neuroprotection. Their findings suggest potential development of novel therapies for diseases such as Parkinson’s, that target nicotine receptors: according to experiments performed on brain cells of mice, they found that nicotine seems to provide protective effect against some type of neuron loss, a symptom widely associated to Parkinson’s disease.

Of course, as Gerald Weissmann, Editor-in-Chief of The FASEB Journal, comments on ScienceDaily: “If you’re a smoker, don’t get too excited. Even if smoking protects you from Parkinson’s, you might not live long enough to develop the disease because smoking greatly increases the risk for deadly cancers and cardiovascular diseases [...]” Still, this discovery is significant. Not only in terms of Parkinson’s diagnosis and treatment, but also because it shows that a usually ill-considered substance such as nicotine can have some positive effects – it might be a matter of dose after all! This is a lesson for scientists, who sometimes tend to neglect fields of research on the pretext they are not fashionable enough, and also for those who fund scientists: it is probably not the simplest task to raise money for studying such ill-reputed compound as nicotine.

References:

D. Toulorge, S. Guerreiro, A. Hild, U. Maskos, E. C. Hirsch, P. P. Michel., The FASEB Journal 2011, 25 (8), 2563 DOI: 10.1096/fj.11-182824

ScienceDaily. Retrieved August 1, 2011, from http://www.sciencedaily.com­/releases/2011/08/110801111738.htm

*born Philippus Aureolus Theophrastus Bombastus von Hohenheim…

When input strands are added to a mixture containing the sophisticated DNA system, cascade reactions between the DNA strands are initiated, that sequencially zip and unzip from one another depending on the inputs. After the computation has been performed (ie, the cascade reactions stop), the response appears under the form of a given fluorescence colour. For each output, a specific colour indicates ‘0′, and another colour corresponds to ‘1′ (like ‘real’ computers, this one works in binary numbers). The researchers used the ’square root solving problem’ to demonstrate the capacities of their system. However, one of the remarkable points of the piece of work is its very systematic design: one can therefore imagine different function for such a system, like diagnosing illnesses: such a device could provide specific responses depending of what chemicals are present in a patient’s blood, for example.

After this first charge against conservative academic research came the second strike, still in Nature, in the form of a whole issue (!) entitled “The future of the PhD”. This time it is not about chemistry only, but about the PhD system as a whole. A series of articles (“Education: the PhD factory”, “Education: rethinking PhDs”) and opinions (“Reform the PhD system or close it down”, “What is a PhD really worth?”, “Fix the PhD”) highlight the qualities and defaults of PhDs – and raise numerous hot debates among readers. Essentially, there are more PhD students and more doctoral programmes than ever, and not enough academic positions for all these graduates – in most fields, the only jobs PhD students have ever been trained for. Consequently, hosts of PhDs will have to spend 5 or 10 tiresome years in ill-paid postdocs (waiting for an hypothetical academic position) or go to work in industry, but won’t be prepared for that: too specialized, not having the required ‘real-world’ experience, too expensive, etc. None of these perspectives seems appealing, particularly when speaking of people who spent years and significant amounts of (taxpayers’) money to achieve the highest levels of education.

There is probably no ready-made solution to these questions, but they must be of direct concern to the research world – particularly, to PhD students and recent graduates: they must be aware of the opportunities – or lack of them – that await them in the ‘post-doctorate’ (in the literal sense) world, and of what it takes to be more attractive for a future career: broad field of knowledge, soft skills and profesionnal education.

The importance of rare earth elements is less obvious that that of more common resources – we don’t eat them nor power our cars with them. However, their use in many of recent high-tech innovations make them an invaluable resource for the decades to come: computer hard drives contain neodymium and dysprosium, tellurium is used in solar cells, and several rare earth elements are so far irreplacable in optical devices such as lasers, LEDs and phosphors. Although rare earths are not so scarce, their distribution on earth is uneven – and more than 90% are currently produced in China. The US and other countries consider (re)opening mining sites, but for the upcoming years, China will have an increasing weight and decision power over prices and distribution of rare earths.

In order to ensure a sustainable use of scarce elements, strong incentives will be needed. For example in Japan, a country without such resources which industry highly depends on importation, the Element Strategy Initiative is a good example of such efforts.[2] Besides reuse and recycling, the potential lack of such elements can be regarded as another challenge for researchers worldwide, who are trying to find alternative materials, thus reducing the need for rare earths in the future.[3]

More generally, the rare earth issue reflects a more general problem that may occur in the upcoming decades: I remember a seminar where a professor mentioned that, if the current trends go on, we will be running out of most precious metals (e.g., rhodium, platinum) in less than a hundred years. Further, resources of lithium (for rechargeable batteries) and phosphorous (for fertilizers) are also limited. In every single field, from ’simple’ food production to state-of-the-art technologies, the limited resources of our planet will eventually constrain us to play the equilibrist’s game of long-term sustainability.

References:

[1] Nature Materials 2011, 10, 157. DOI: 10.1038/nmat2985
[2] Nature Materials 2011, 10, 158. DOI: 10.1038/nmat2969
[3] Nature Materials 2011, 10, 162. DOI: 10.1038/nmat2973

See also:

Nature Photonics 2011, 5, 1. DOI: 10.1038/nphoton.2010.308

The second, more recent example of poor communication is provided by the recent buzz that accompanied the publication in Science by researchers from the NASA astrobiology institute and the US geological survey of the existence of bacteria that can integrate arsenic under certain conditions – a discovery that clearly expands the view of what it takes for living things to survive. The purpose here is not to discuss the validity of the presented science (others have done it better) but the way the information was handled and passed to general public. A few days before the official publication of the article, I found on the web page of a swiss popular journal an intriguing title about a discovery that “will impact the search for evidence of extraterrestrial life”, and was quite excited to see what it was about. Then came the proper article in Science. Although the research was quite interesting, I had some difficulties to see the direct link with extraterrestrial life. This is the first fact that is disturbing to me and, I imagine, to the general public: the press release promises E.T. and the finding turns out to be a bacterium… not so impressive at first sight! The second disturbing fact is the way the involved research team treated the (sometimes quite harsh) criticism that burgeoned soon after the release of the Science article: at first, they refused to address any type of criticism (see here), claiming that any further debate should be peer-reviewed as the article had been. It is perfectly understandable that they were not going to reply to every random blog commenting about their findings, but as they did start the fanfare with the initial press conference, they were expected to take their responsibilities when questions would come.

In retrospect, one of the very visible and damaging consequences of both cases appeared in recent interviews of the protagonists: Phil Jones for the infamous climategate at the University of East Anglia, and Felisa Wolfe-Simon for the bacterium isolated in California: both were unprepared to media exposure and went through extremely hard, exhausting times. This is at most partially their fault: scientists have been cloistered for a too long time in their ‘ivory towers’, and now that they are increasingly confronted to media and the public, they lack skills on how to deal with sudden broad exposure. I even know some professors who simply don’t see the point of talking to the public – there also exist good examples of scientists communicating to the public! – and I would strongly advocate a proper training for scientists in communication, particularly when it comes to speak to broader audiences or under particularly pressuring circumstances.

In order to keep credibility and respect, scientists must communicate to the general public in a way that is both honest and clearly understandable. This results in a general interest for research, as well as a better understanding of money spending by tax payers, who are in most places the first sponsor of science.

The compound has been known for decades to mimic the effects of estrogen in the body. Hence, particular concerns have been raised regarding the absorption of BPA by pregnant women and babies. Particularly, it was suggested that BPA-containing baby bottles should be avoided, since they are extremely likely to leach BPA in baby drinks. Further, BPA was related to illnesses such as obesity, heart disease, cancer, diabetes, fertility problems, and birth defects.

So far, Canada and Australia have been the first countries to classify BPA as toxic (despite recriminations from the chemical industry), and France and Denmark had already banned BPA from baby bottles. On 25 November, 2010, the European Union executive commission decided to ban production, and commercialization, of polycarbonate-based baby bottles containing bisphenol A. The new regulations will be enforced during the first semester of 2011.

However, some criticize the decision, calling it more political than based on sound science, and not every country is ready to ban BPA. In Swizerland, where we usually like to do things differently, the Federal Office of Public Health considers BPA as non-harmful for consumers, since only high doses are known to be problematic. According to them, a ban on BPA would lead manufacturers to employ other, lesser known compounds, which toxicity is still unknown.

Then, is a ban on BPA an over-reaction or a wise precaution? Only the future (and more experiments) will tell.

Further reading:

http://www.nature.com/news/2010/101104/full/news.2010.581.html

This concept was translated at the molecular level, as researchers from Osaka University, Japan, recently reported in Nature Chemistry.  The team led by Prof. Akira Harada developed different polymers bearing either cyclodextrin  rings (a so-called molecular host) or residues that like to sit inside the cyclodextrins (ie., molecular guests). When pieces of both polymers are suspended in water, they find each other and stick together thanks to host-guest interactions at the cyclodextrin sites.

Further, they demonstrated that by modifying the host and/or guest moieties, the strength of the sticking interaction can be tuned or maximized. Remarkably, the interaction can be strong enough to prevent the polymers to be pulled apart without breaking them.

Two different polymeric gels are brought in contact, and the cyclodextrins (yellow) bind to adamantane residues (green).

Molecular self-assembly is a well-known phenomenon at molecular scale in chemistry and biology. However, it had never been demonstrated at a macroscopic level. As Prof. Phil Gale from University of Southampton, UK, comments on Chemistry World, ‘Why didn’t anyone think of this earlier?’ Indeed.  This first demonstration can potentially result in many applications, particularly in the field of surface and membrane coating.

Additional material: Polymer blobs stuck with molecular velcro

Reference: A. Harada et al., Nature Chemistry 2010 DOI: 10.1038/nchem.893

In a recent article in Science, Pires et al. report a new lithographic method based on the local desorption of an organic resist by a heatable probe. A hot, sharp tip is employed as a nano-pen to scratch a surface covered by a layer of a polyphenolic compound. Repeating the process over and over again results in 3-dimensional patterns, and the obtained motif can be transferred to various substrates. For example, they started by carving the IBM logo, but then needed a more demanding task. They tackled the challenge offered by the well known Matterhorn shape. The nanomountain was carved into a 100 nm thick film after 120 separate steps. The model they created (picture below) stands 25 nanometers tall, which is 179′120′000′000 smaller than the 4478 meter high Matterhorn!

AFM scan of the replica of the Matterhorn written into the molecular glass

New methods for nanofabrication allowing to create functional structures are highly seeked, and research such as that presended here is promising, because it seems to be scalable to more practical uses.