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Who will get the 2014 chemistry Nobel?

30 September, 2014 - 15:10

With just under week until the announcements start, Nobel prize fever is officially here.

The official shortlist is shrouded in secrecy, giving those making their predictions about who might win little to go on – but that hasn’t stopped them.

— Nobel medal

As usual, Thomson Reuters have released their Nobel forecast, which uses citation numbers and other statistical wizardry to predict the winners in each category. This approach has successfully predicted 35 Nobel prize winners over the past 12 years.

This time round they highlight three possible chemistry winners – the inventors of the light emitting diode (Ching Tang and Steven Van Slyke), RAFT polymerization (Graeme Moad, Ezio Rizzardo, San Thang) and mesoporous materials (Charles Kresge, Ryong Ryoo, Galen Stucky).

Elsewhere, less official speculations – perhaps based more on a hunch – have begun flying around.  On the Everyday Scientist blog, chemist Sam Lord has put together some suggestions. Like the number crunchers at Reuters, Lord has some past successes (though he didn’t predict last year’s computational chemistry winners - Karplus, Levitt and Warshel). He thinks the 2014 prize could go to a key historical invention, such as the contraceptive pill, or the lithium-ion battery (also a top pick for The Curious Wavefunction blogger Ashutosh Jogalekar), but also mentions broader areas such as microfluidics, nanotechnology and next-generation sequencing. If last year is anything to go by, there’s much to be said for gut feeling as well as advanced number crunching. As always, we’ll just have to wait a little longer for that all-important announcement from Sweden.

If you want to get into the Nobel spirit and hear more about the possible winners this year, our features editor Neil Withers joined representatives from Nature Chemistry and C&EN to begin the countdown to the 2014 chemistry Nobel in a Google hangout – watch the whole discussion here.

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Categories: Education

Nylon – a bit of a stretch

25 September, 2014 - 14:41

Guest post by Rowena Fletcher-Wood

I first heard the story of the discovery of nylon during a chemistry class in school – it was told as a serendipitous discovery. A young lab assistant, clearing up at the end of a long day, clumsily poured two mixtures in together and noticed a precipitate. Dipping in a stirring rod, he pulled out a thin string, which he stretched out into a tough, translucent fibre. He realised the potential of his discovery, reported it to his superiors and left them to the tiresome job of working out what he had done to make it.

The invention of nylon created a revolution in hosiery
©Shutterstock

It’s funny how we use accident to shape our understanding of discovery and achievement, as though we want to excuse hard work and apologise for years of learning. It’s somehow disappointing, unromantic: the story of research whisks away that tantalising fantasy of stumbling upon treasure, reserving discovery for the experts.

The real story of nylon, interesting though it may be, is a bit of stretch from serendipity.

There was a young lab assistant, and his name was Julian Hill. He was working in the DuPont research laboratory, led by the rigorous organic chemist Wallace Hume Carothers, who had taken on the challenging ‘synthetic fibre race’. At the time, synthetic polymers were a mysterious conception; what they were made of and how they related to simpler compounds was unknown. The DuPont team had studied complex natural products such as cellulose and silk and from their understanding had developed polyamides through the condensation of dicarboxylic acids with diamines – fantastically interesting but, at the time, not particularly useful.

Discovery of nylon, 1941 re-enactment. DuPont chemist Julian Hill (1904-1996) carrying out a re-enactment in 1941 of the discovery of nylon in 1935. A glass rod is being used to pull threads from the sample prepared in a glass tube. This discovery was made at DuPont’s Experimental Station near Wilmington, Delaware. Hill was a member of the team, along with other chemists. The molasses-like mass stuck to the glass stirring rod and was drawn out into a thin fibre. After more research and development, DuPont was able to commercialise the new material. Production started in 1939, twelve years after the research program had started in 1927. Credit: Hagley archive/Science Photo Library

Julian Hill had been working with polyester when, dipping in a stirring rod, he pulled out a thin string, which he stretched out into a tough, translucent fibre – just like in the story I was told. But this was not considered extraordinary. Often, discovery is not about observing properties, but recognising them. One day, when Carothers was absent from the lab, the chemists decided to go rogue with the polyester and have a competition to see how long they could stretch it. They raced down the hall, delicately extending the fibre. They had extended it to four times the original length when it stopped. It would not stretch any more.

Suddenly, Hill understood: as they stretched the fibre, chains of molecules snapped into position, orienting themselves into a chain of a discrete thickness. This would be the basis for the first fully synthetic fibres.

But nylon was far from invented. The melting points of the polyesters they had were far too low for any practical applications, and so they returned to polyamides and began stretching those instead. It took 9 months, a patent for the ’cold-drawing’ process of making fibres by removing them from the water of condensation, and 80 new polyamides before the most promising, nylon-6,6, was discovered in May 1934.

Nylon, a dyeable, durable, shiny thermoplastic first entered the market in 1938 as the bristles of a toothbrush, before being appropriated for women’s hosiery in 1940. DuPont declined to trademark the name ‘nylon’, instead allowing it to enter the lexicon as an alternative name for ‘stockings’. The new ‘nylons’ were a huge success. Nowadays, this fantastic fabric, which leaves a lower carbon footprint than wool, is used for meat wrappings, instrument strings and carpets, amongst many other things. Its only downside is its toxicity upon heating: it melts rather than burns, and breaks down to produce hydrogen cyanide.

This is ironic, actually, because Carothers never got to see his creation take hold. In 1937, just as his achievements were being celebrated and developed, he committed suicide with cyanide. He had suffered with depression and was grieving for the loss of his sister, but his suicide came as a shock. The suicide has been described as an ‘embarrassment’ for DuPont, and records relating to Carothers were lost or destroyed. This may help to explain why the discovery of nylon has since been wrapped in myth and mystery.

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Categories: Education

A short time ago in a journal not so far, far away…

18 September, 2014 - 14:16

Guest post from Tom Branson

Inside Back Cover: Selective Targeting of Tumor and Stromal Cells By a Nanocarrier System Displaying Lipidated Cathepsin B Inhibitor (Angew. Chem. Int. Ed. 38/2014)
Angewandte Chemie International Edition
Volume 53, Issue 38, pages 10251-10251, 22 JUL 2014
DOI: 10.1002/anie.201406845
http://onlinelibrary.wiley.com/doi/10.1002/anie.201406845/full#car1

Science fiction often predicts future advances and has even prompted the development of some technologies. So should we be taking advantage of this association? Can we use a science fiction setting to showcase science fact? That idea is exactly what the latest cover of Angewandte Chemie has attempted to do.

It’s a trap!

There may be some of you who don’t immediately recognise the image above. It’s an homage to a scene in the Star Wars movies, where the plucky rebel alliance (piloting the small x-wing fighters) mount an attack on the Death Star, a moon-sized weapon of mass destruction and flagship of the evil empire. Hijacking this iconic scene is a certain way to grab the attention (George Lucas himself used it twice), especially by tapping into the current hype for the forthcoming films. But there doesn’t immediately appear to be a solid link between the rebel’s cause and Angewandte’s publishing ideals. In this case I’m not sure if the cover image really works to enhance and explain the research or actually provides a distraction from the science within. It’s certainly a fun image and a good way to get instant recognition of an idea, especially with fans of the franchise. That idea being the destruction of the evil empire, or in this case, evil cells.

In this interpretation the x-wing fighters have their own force fields and are carrying pills towards the Death Star, which itself looks to be in a dire state probably due to the growths in its innards. It should be a straightforward mission as long as the ships watch out for rogue fluorescing cells and a giant-lipidated-space-peptide.

This cover is very similar to an example from 2012 that also showed up in Angewandte. In both cases the empire, represented by the Death Star, took a beating, suggesting that there’s no sympathy for the Sith in the scientific community. For balance, I’d like to see someone’s interpretation of a Death Star nanoparticle destroying the peaceful bacterial population of Alderaan (I will accept joint authorship).

Stay on target

I love all things Star Wars (excluding Jar Jar Binks, of course) but this latest tie in to the franchise does seem a little out of place with the expanded Star Wars universe. No mention of carbonite or even ion cannons. But it does hint at the true content of the article: a new targeted drug delivery method. The group led by Boris Turk and Olga Vasiljeva from the Jožef Stefan Institute in Slovenia, have developed lipid vesicles conjugated to peptides that target extracellular cathepsin B (CtsB). CtsB is a cysteine protease that only translocates to the cell surface during cancer progression and is therefore a cancer-specific target. The research showed fluorophores and anticancer drugs could be transported in their vesicles and target the tumour environment.

For more about targeting cancer and less about the rebel alliance’s struggle, have a look at Angewandte Chemie.

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Categories: Education

Fried eggs, frying pans and fluoropolymers

16 September, 2014 - 15:57

Guest post by Jen Dougan

Of all the components of a cooked breakfast, a perfectly fried egg is arguably the most important. It’s for that reason, despite the myriad of other factors to consider – size/weight/colour/celebrity chef endorsement – that a frying pan’s non-stick credentials are key.

Polytetrafluoroethylene (PTFE), the ‘big daddy’ of non-stick, was discovered by accident in 1938. While attempting to make a new CFC refrigerant, American industrial research chemist Roy J. Plunkett noticed that a cylinder of tetrafluoroethylene had stopped flowing but its weight suggested something still inside. In his own words, ‘more out of curiosity… than anything else,’ Plunkett and his assistant cut open the cylinder to discover it was packed at the bottom and sides with a white, waxy solid. Analysis showed that the material was chemically inert, thermally and electrically resistant, and had very low surface friction.

What they had discovered was PTFE, a linear fluoropolymer prepared by the free-radical polymerisation of tetrafluorethylene. The carbon–fluorine bond is the strongest single bond in organic chemistry and the fluorine substituents shield the carbon skeleton from attack, making it chemically inert. Because of its useful material properties (and far from thoughts of fried eggs) PTFE was branded as Teflon and found uses in the Manhattan project, aerospace industries and even gecko research (it is the only known material to which a gecko’s feet cannot stick). But how did Teflon make its way from nuclear research into our kitchens?

By the 1950s Teflon was being used in fishing lines and a French woman asked her husband, an engineer, to coat her aluminium cooking pans with the material. PTFE-coated non-stick cookware was created, and launched as TefAl (from Teflon Aluminium). By the 1960s PTFE–coated cookware was being used in kitchens on both sides of the Atlantic.

However, on searching recently for a new frying pan I found many instances of implied safety issues with PTFE, mostly from ‘eco pan’ manufacturers and advocates. Two main themes recurred in accusations against PTFE cookware: concerns over perfluorooctanoic acid (PFOA), a surfactant used in its production, and ‘polymer fume fever’ – symptoms caused by inhaling polymer decomposition products.

PFOA is an environmentally persistent chemical and, in the mid-2000s, was classified by the US Environmental Protection Agency (EPA) as ‘likely to be carcinogenic to humans’. DuPont, a major user and producer of PFOA, settled with the EPA in 2005 over its failure to report possible health risks associated with PFOA. While PFOA is not present in PTFE cookware itself (it is destroyed during the manufacturing process), it was an environmental concern and after EPA stewardship, PFOA is no longer manufactured nor used by the major global fluoropolymer manufacturers, including DuPont.

Aside from PFOA concerns, PTFE coatings do begin to degrade at 260 °C. The decomposition of the polymer coating produces fumes, which, if inhaled, can cause ‘polymer fume fever’ – temporary symptoms much like the flu virus (see Shusterman DJ, Occup Med. 1993 8(3) 519). But just how likely is this to occur? It is possible to rapidly heat a pan to >260 °C, but if you follow the manufacturer’s instructions and don’t heat an empty pan,you would likely avoid any instances. The most common fats used in cooking have a smoke point well below 260 °C, which should act as a sufficient indicator of pan temperature and kitchen safety. Obviously, heating the pan without fat as a temperature gauge is riskier and should be avoided.

Still not keen on PTFE? There are alternatives. Used for cookware since the Han Dynasty in China (206 BC – AD 260) and still popular with cooks today, cast iron pans have unquestionably stood the test of time. Cast iron frying pans come bare or with an enamelled coating. Bare cast iron pans are porous and to achieve a non-stick finish worthy of a fried egg, oil is polymerised to form a hydrophobic layer across the pan surface. This process, known as ‘seasoning,’ can be repeated as required (depending on treatment of the pan), though is usually recommended yearly.

I’m satisfied that with normal use, PTFE pans will produce perfectly fried eggs without adverse health effects (apart from a risk of increased cholesterol). The only remaining question is whether to have them over-easy or sunny side up?

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Categories: Education

Meet our guest bloggers – Jen Dougan

16 September, 2014 - 13:53

My name is Jen Dougan and I am a Field Applications Scientist with an SME, developing diagnostic tools for clinical analysis. My job involves working with our R&D teams and customers in the field to drive and support product and applications development.

I recently moved into this position after a PhD and two post-docs (and a brief stint in science policy) in bio-nano-analytical chemistry. What I’ve loved about the transition into this role is the chance to ask questions and provide answers in a fast-paced, rigorous environment. It’s been fantastic to see some of the techniques used through my PhD and post-docs in action in a clinical setting.

Real world applications of chemical research are a central theme of this blog. I’ll be contributing regular posts here, to explore the chemistry in our every day lives. From the clothes we wear to the goods we use, it really is a chemical world.

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Categories: Education

Academic family: Sir Harold Kroto

11 September, 2014 - 17:35

Guest post by JessTheChemist

Scientists have a responsibility, or at least I feel I have a responsibility, to ensure that what I do is for the benefit of the human race’ – Harry Kroto

Thank you for your nominations for this month’s blog post. It was great to see so many of you getting involved in this series, highlighting interesting Nobel laureates for me to cover. However, I could only pick one winner, so I decided to write about Harry Kroto, inspired by this tweet from Bolton School:

@ChemistryWorld @JessTheChemist How about Bolton School Old Boy 'Sir Harry Kroto'?

— BoltonSchoolChem (@Chem_BoltonSch) August 20, 2014

Harry Kroto has a formidable CV. Not only is he a highly distinguished and talented chemist, but he does a great deal to improve the teaching of chemistry to future generations. This has included setting up the not-for-profit Vega Science Trust, which helps scientists communicate with the public at large, and even returning to his childhood school to build Buckyballs with students.

Kroto began his career at the University of Sheffield where he gained his PhD in high resolution electronic spectra of radicals. After time spent in Canada and the USA, he returned to the UK – to the University of Sussex – to begin his independent research career. His research concentrated on the identification of carbon chains in the interstellar medium, which included work at Rice University, where Kroto and colleagues, Richard Smalley and Robert Curl, discovered the existence of C60 or Buckminsterfullerene. The discovery itself has become a well known scientific story, recently retold by Rowena Fletcher-Wood here on the Chemistry World blog. After numerous publications on the subject, Curl, Kroto and Smalley were awarded the Nobel Prize in chemistry in 1996 ‘for their discovery of fullerenes’. As with many other Nobel laureates, there’s a detailed biography of Kroto published by the Nobel foundation here.

Kroto is related to a number of influential scientists. He is distantly related to Roger Kornberg, who won the Nobel prize in chemistry in 2006 for his work on the molecular basis of eukaryotic transcription. Kornberg was lucky enough to work for the Nobel prize winner, Francis Crick, who famously contributed to the proposal that DNA had a double helical structure, along with James Watson.

Kroto’s academic partners and fellow Nobel prize winners, Curl and Smalley also have impressive scientific pedigree. Curl’s academic father was E. Bright Wilson, a pioneer in spectroscopy, and grandfather was Linus Pauling, who won both the Nobel prize in chemistry and the Nobel peace prize. Curl is also academic brother to Dudley Herschbach, winner of the Nobel prize in chemistry in 1986 for contributions towards the molecular dynamics of elementary chemical processes. Hershbach shared the prize with the Hungarian-Canadian chemist John Polanyi and Yuan T. Lee, the first person from Taiwan to be awarded a Nobel prize. Smalley is academically descended from William Lipscomb, who took the 1976 Nobel prize in chemistry for his contributions to borane chemistry. Not shown in our family tree are Thomas Steitz and Ada Yonath, who both went on to win Nobel prizes after time spent in Lipscomb’s lab. Lipscomb also demonstrated his sense of humour by regularly presenting at the Ig Nobel awards. Curl is also connected to Peter Atkins, author of undergraduate students’ favourite physical chemistry textbook!

Sir Harry Kroto's academic family tree

As you can see, Kroto has an eclectic lineage, and rich academic family history, from chemical biologists to physical chemists. Do you want to know what your academic genealogy is? If so, head to academictree.org, where you can add yourself to the website and start creating your very own tree.

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Categories: Education

Funding for fiction’s favourite poison

9 September, 2014 - 13:46

‘As for monkshood and wolfsbane, they are the same plant, which also goes by the name of aconite.’ – Severus Snape, Harry Potter and the Philosophers Stone by J. K. Rowling

In Harry Potter’s very first potions lesson he learnt about the magical properties of aconite. Muggle chemists, it seems, are only one step behind the magical world.

©istock

Aconitine – spelt slightly differently by scientists – has a highly complex structure that has never before been synthesised in the lab. But now, Duncan Gill from the University of Huddersfield, UK, has been awarded a £133,481 grant to develop a synthetic route to obtain this illusive molecule.

Attempts to make aconitine began after Czech chemist Karel Wiesner revealed its chemical structure in 1959. Weisner went on to publish several papers on the synthesis of alkaloids and terpenoids, an important initial step towards making the molecule. However, it wasn’t until last year that a major milestone was reached, when a team of researchers from the Memorial Sloan Kettering Cancer Institute, New York, announced the total synthesis of the related compound, neofinaconitine. Building on the work of his predecessors, Gill will have to develop new chemical methods to reach his target molecule.

If successful, Gill, who has previously worked as a process chemist at AstraZeneca, will need to be particularly careful when handling this compound. Aconitine is a potent neurotoxin and has been dubbed the ‘Queen of poisons’. One of the most notable references to aconitine comes from William Shakespeare’s Romeo and Juliet: it is the main ingredient in the toxic potion drunk by Romeo with fatal consequences.

The grant has been provided by the Leverhulme Trust and will be enough to employ a full-time post-doctoral advisor. Only time will tell if they can bring this fictional favourite to life in a laboratory setting.

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Categories: Education

The ‘ooh, that’s interesting’ moment

4 September, 2014 - 16:29

Guest post by Heather Cassell

©Shutterstock

Sometimes it happens when I’m reading a research paper, sometimes when I’m doing an experiment, analysing data or learning a new technique; or more often when I’m reading Twitter. It’s that moment when you discover something new and interesting, or re-discover a fact that you used to know, and it makes you pause and think ‘ooh, that’s interesting’. For me the discovery usually leads to a massive detour into reading things other than those I was meant to be reading or working on, but I always learn something from it and sometimes it’s actually relevant to my work. Whether it directly affects research or not, the ‘ooh, that’s interesting’ moment is at the heart of scientific investigation.

It can be great when it happens during an experiment, but it can also be deeply frustrating. An unexpected result forces you to seriously consider what is happening and to plan more experiments to further examine the anomaly. This encourages you to combine techniques, make use of all of the resources at your disposal or even seek out new collaborators. If the anomalous result is reliably proved correct and reproducible, then you will need to do more research to explain it. At its best, this is a very exciting time as you will get to learn new skills, create new knowledge and develop partnerships. At its worst, it can shatter your previous assumptions or even show that your idea or product is not as good as you think.

Personally, I really enjoy the flurry of activity associated with learning something new, especially a new experimental technique. I was recently involved with some experiments using atomic force microscopy (AFM) – I had a vague idea of what it was but I had never used this technique before. The analysis produced some amazing pictures but I had no idea what they meant, so I spent an enjoyable afternoon learning all about how AFM works and comparing the results we produced with results already published. The next time we used the machine I could analyse the images as they were formed, which was really helpful for determining if it was showing what we wanted or not. The ‘ooh, that’s interesting’ moment had provided the push I needed to learn a new skill.

Outside the lab, I really love spending time on Twitter. With so many scientists (and non-scientists) from different fields providing links to articles and blogs, there’s always more than enough to read. Just 10 minutes reading tweets can leave me with countless browser tabs open and new favourites to read. It’s now easier than ever to share your ‘ooh, that’s interesting’ moments with the world, meaning a tweet from a researcher half way across the globe can inspire new ways to think about my own research.

It is this process of discovery and continuous learning that is one of the main things I love about science. Now, back to Twitter…

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Categories: Education

Oranges and Lemons

28 August, 2014 - 16:33

Guest post by Rowena Fletcher-Wood

Scurvy plagued early sailors, and although many treatments were tried and promoted, a simple cure was masked for centuries behind a series of mistakes and misunderstandings.

This story begins at sea, long into a voyage after the fresh food stock had long run out and the sailors were left with only grains, hardtack and cured meats to eat. The sailors would become desperate as scurvy began to set in. Sailors were lost to scurvy in vast numbers, with estimates as high as two million lives lost between 1500–1800 AD.

©Shutterstock

Scurvy is an unpleasant disease in every way. Although symptoms take weeks or months to develop, they get very nasty. First you become lethargic, anaemic and pale, and all of your joints and muscles ache. You lose your appetite and begin to develop spots on your thighs and legs. Soon you become feverish, sick, and weak; gums soften and bleed, legs swell, old wounds reopen. Depression sets in. Eventually, scurvy takes hold completely: your teeth fall out and gums turn blue, you bleed beneath your skin and from the follicles of hairs. You suffer cardiac arrest and die.

Scurvy is caused by a deficiency in vitamin C (ascorbic acid), which is present in many foods – including tomatoes, sweet peppers, strawberries and spinach – but in particular citrus fruits. Several pathways in the body rely on vitamin C; it is vital for building collagen in tissues. We also use it for lipid metabolism, neurotransmission and strengthening bone and blood vessels. Although many species are capable of synthesising their own vitamin C, humans and a few other animals cannot – it is an essential nutrient that must come from our diet. But until 1927, we didn’t even know it existed.

The ancient Greek physician Hippocrates knew that fresh fruit, especially citrus, had an antiscorbutic effect – it could prevented and cure scurvy. In 1747, James Lind systematically proved that the addition of citrus fruit to the diet both treated and prevented the disease, in a candidate for the first ever clinical trial. But the medical establishment were not convinced, and continued to promote other approaches, including good hygiene, exercise, avoiding tinned meat and improving morale. Some of these approaches were successful, including prescribing the peppery herb scurvy-grass, which is related to horseradish. Unknown at the time, scurvy-grass leaves are rich in vitamin C.

A common belief was that the acidic principle treated scurvy: doctors believed any acid would do and that citric acid in fresh fruits was merely the best. Accidental destruction of ascorbic acid in treatments that would otherwise have been effective was common. Although vitamin C is present in milk, this was destroyed by the new process of pasteurisation, leaving bottle-fed babies susceptible to scurvy. James Lind himself was guilty too, bottling and selling lime juice that promptly oxidised and became useless.

When the 1867 Merchant Shipping Act insisted that all ships carry citrus fruits, fresh lemons were substituted for cheap, abundant West Indian limes which were more acidic but had only a quarter of lemons’ ascorbic acid content. These fruits were juiced, stored in air and piped through copper tubing, oxidising the vitamin C. Later tests in 1918 showed the juice to be almost useless, but at the time this was masked by simultaneous advances in diet and marine travel that reduced the prevalence of scurvy.

We owe the discovery of vitamin C to guinea pigs. Two Norwegian physicians, Axel Holst and Theodor Frølich, decided in 1907 to induce in guinea pigs a disease called beriberi, now known to be cause by a deficiency of vitamin B1. They used the same dietary restrictions they had used to induce the disease in pigeons, but the guinea pigs developed scurvy instead. Pigeons produce their own vitamin C, but like us, guinea pigs cannot. This was an exciting moment in medical history: the diseased guinea pigs were the first examples of non-human scurvy sufferers.

In 1932, the Hungarian biochemist Albert Szent-Györgyi posted a sample of hexuronic acid – which he had isolated in 1927 – to the University of Pittsburgh, asking them to test it on guinea pigs with scurvy. The results would gain him the Nobel prize for medicine five years later, and hexuronic acid was renamed ascorbic acid to celebrate its antiscorbutic effect.

Decades of nutritional experiments and almost–correct hypotheses had seen scurvy become increasingly rare, but it took almost 200 years – from Lind’s nutritional trials to Szent-Györgyi’s experiments – to identify the secret in citrus fruits.

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Categories: Education

A professional makeover for the old reaction scheme

21 August, 2014 - 17:50

Guest post from Tom Branson

A bright new reaction scheme has found its way to the cover of Inorganic Chemistry. Not content with old standard representations, this journal has been given the professional touch.

Framing metal complexes

The image puts a well needed shine on the conventional reaction scheme and perhaps suggests that we should now be teaching undergrads to paint as well as honing their ChemDraw skills. Two states of a porphyrin derivative complexed with zinc are shown here framed in audacious, golden swirls. And why not? If you’re proud of your work then go ahead and put a huge golden frame around it.

Let’s take a look at that zinc phthalocyanine complex, expertly drawn binding to HS. Then give it a proton, follow the two giant arrows and you reach liberated hydrogen sulfide and the original zinc phthalocyanine. In case you hadn’t got it yet, the artwork explains for us that this process is all about protonation. The background is also a nice touch. A fantastic network of neurons is on show, blasting off new thoughts of possible bioinorganic applications. Hydrogen sulfide is known to play a role in neurotransmission and its reactivity with metal complexes may find practical applications in that field.

This journal cover art was created by artist Shanna Zentner. She was recommended to the authors of the article by colleagues at the University of Oregon, after she had previously produced artwork for other faculty members.

Zentner’s foray into the scientific literature started when her husband needed a cover for a chemistry journal. They thought a painting of the research would do nicely and so Zentner’s chemistry art career took off. Since then her painting skills have been commissioned for a number of other journal covers, with the artist and scientists often meeting to discuss the work and how to develop the imagery. Zentner champions science communication and believes that this type of work is ‘invaluable to the advancement of scientific literacy in the general public.’

Hydrogen sulfide reactivity

The actual research probes more deeply into the mechanism of H2S binding to both zinc and cobalt phthalocyanine complexes. The team, led by Michael Pluth, show that whilst the zinc variety reversibly binds HS, the cobalt complex is instead reduced by HS and can be oxidised back when exposed to air. This redox activity results in a colour change that could be used in colorimetric HS detection.

Head over to Inorganic Chemistry for the full article and more bright results with metal phthalocyanine complexes.

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Categories: Education

Academic family: Sir William Ramsay

14 August, 2014 - 16:46

Guest post by JessTheChemist

‘The noblest exercise of the mind within doors, and most befitting a person of quality, is study’ – Ramsay

A few years ago I had the pleasure of meeting Jack Dunitz at the Swiss Federal Institute of Technology (ETH) in Zurich. Little did I know that he was the academic great-great-grandson of the UK’s first chemistry Nobel Laureate, Sir William Ramsay. After discovering this connection, I decided to delve deeper to see which other chemistry legends Ramsay is connected to.

Ramsay began his career as an organic chemist, but his prominent discoveries were in the field of inorganic chemistry. At the meeting of the British Association in August 1894, Ramsay and Lord Rayleigh both announced the discovery of argon, after independent research. Ramsay then discovered helium in 1895 and systematically researched the missing links in this new group of elements to find neon, krypton, and xenon1. These findings led to Ramsay winning his Nobel prize in 1904 in ‘recognition of his services in the discovery of the inert gaseous elements in air, and his determination of their place in the periodic system’.

Ramsay worked with a wide range of chemists before winning his Nobel prize. At the start of his career Ramsay worked with Rudolf Fittig in Tübingen, Germany. Fittig, a successful organic chemist, is particularly known for discovering the pinacol coupling reaction. Ramsay’s noteworthy academic brothers via Fittig are Ira Remsen and Theodor Zincke. Remsen is recognised for contributing to the discovery of the first artificial sweetener: his co-worker, Constantin Fahlberg, accidentally discovered Saccharin by failing lab etiquette 101 – not washing his hands after a day working in the laboratory.2 On the other hand, Zincke is most famous for supervising the father of nuclear chemistry, Otto Hahn, who claimed the Nobel prize in chemistry (1944) ‘for his discovery of the fission of heavy nuclei’.3 This makes Ramsay the academic uncle of Hahn.

As well as academic brothers and nephews, Ramsay’s direct academic descendants have also achieved greatness. Frederick Soddy, Ramsay’s academic son, carried out research into radioactivity and proved the existence of isotopes, for which he won the 1921 Nobel Prize in chemistry.4 Unfortunately for the chemistry community, Soddy’s interests diverted to economics and politics, so he has no prominent academic offspring to speak of. Interestingly, he also has a lunar crater named after him! Other chemistry Nobel prize-winning descendants of Ramsay include the two-time winner, Frederick Sanger (1958, 1980), and Barry Sharpless (2001), who are both his academic great-great-grandsons. Ramsay also has more diverse Nobel prize winners in his family tree, with two winners for physiology or medicine: Har Gobind Khorana (1968) and Konrad Bloch (1964).

This summary of Ramsay’s academic family is by no means the complete list, but this does demonstrate that one great chemist can have an enormous effect on the generations of chemists to come. As you can see, Nobel prize winners seem to have excellent academic dynasties, but perhaps it isn’t the fact that their mentor won a Nobel prize that inspired them to greatness but their work ethic and abstract way of thinking.

In future posts we will look at other Nobel prize winners and the effect that they may have had on their academic offspring. If there is a particular winner that you would like to see featured, you can contact me on Twitter (@Jessthechemist).

 

References

1: Sir William Ramsay – BiographicalNobelprize.org. Nobel Media AB 2013. Web. 6 Jan 2014.

2: Chemical Heritage Magazine ‘the persuit of sweet:a history of saccharin’

3: Otto Hahn – Biographical. Nobelprize.org. Nobel Media AB 2013. Web. 6 Jan 2014.

4: Frederick Soddy – Biographical. Nobelprize.org. Nobel Media AB 2013. Web. 7 Jan 2014.

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Categories: Education

Meet our guest bloggers – Jessica Breen

14 August, 2014 - 16:24

I am a postdoctoral fellow at the Institute of Process Research and Development (iPRD) at the University of Leeds. My research is on the synthesis of chiral amines relevant to the pharmaceutical industry but I have a general interest in organic chemistry, catalysis and sustainable methodologies. When I am not in the lab, I blog at The Organic Solution on a range of topics including chemical research, postdoc life and outreach experiences. Recently, I have become interested in the connection between chemists across the globe which has led me to create an academic twitter tree.

To continue this academic tree theme, this blog will explore certain strands of the chemistry Nobel Laureate family tree using the Royal Society of Chemistry’s Chemical Connections. The blog will delve into the life and heritage of different chemistry Nobel Laureates and, amongst other things, we shall find out if having a Nobel winner in your lineage could have an effect on your career, for example, does having a Nobel winner in your ancestry mean you are more likely to achieve academic greatness? If there is a Nobel winner that you would like to see featured, please get in touch.

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Categories: Education

Tales of the abandoned glassware

7 August, 2014 - 12:21

Guest post by Heather Cassell

Mysteriously abandoned?
©iStock

I love working in the lab. I’m happiest when I’m pottering about among the bottles and the beakers getting on with my work. Most of my experience has been in multi-group labs of varying sizes; all have generally been good fun to work in, with lots of people to talk to who each have different skills and experiences. This can be very useful when you need any help, especially when you are learning new techniques.

One thing you can rely on happening in the lab at some point, especially a large lab used by many groups, is the appearance of Mysteriously Abandoned Glassware. Usually the bottle, beaker, or flask is unlabelled. If you’re lucky enough to have a label, it’s guaranteed to be so faded you can’t read it. Sometimes the glassware contains a colourless liquid; other times a crystalline material, evidence of the previous presence of now long lost liquid. A common variation of the Mysteriously Abandoned Glassware is the flask/beaker of something that has had Virkon (a pink disinfectant) added to it and left in the sink, again with no label in sight to point us to the perpetrator. Over time, the pink Virkon discolours, but the glassware remains Mysteriously Abandoned.

Over the years, I have realised I have a fairly low mess tolerance (compared to the other people I work with), at least in the lab; my office desk is another matter! I like a clean and tidy bench to work on and the same goes for communal areas, so while others are happy to ignore the things that have been left, I find myself doing something about it. I’m always the one tidying up as I am waiting for the centrifuge to run, or doing other lab jobs (filling up hand towels, checking stock levels, emptying disposal bins…). In the case of Mysteriously Abandoned Glassware, I end up trying to find the owner (often a mystery) then trying to work out what it is.

More often than not, the solution is something fairly innocuous like a buffer (Tris or PBS), which we dilute from concentrated stocks, or an alcohol (ethanol or methanol). After I’ve worked out what it is and how to dispose of it, I’ll send the glassware to be washed or do it myself. Within hours, you can guarantee that someone will come and say, ‘have you seen my [insert common solvent here]? I left it somewhere…’ The lab will stay reasonably tidy for a few days or maybe even a few blissful weeks, before another piece of Mysteriously Abandoned Glassware materialises and the cycle continues.

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Categories: Education

Meet our guest bloggers – Heather Cassell

7 August, 2014 - 12:09

I’m Heather Cassell (née Stubley). I did a BSc in biochemistry and genetics at the University of Leeds, then I moved to the University of York where I did an MRes in biomolecular sciences followed by a PhD investigating enzyme activity in non-aqueous solvents. I am currently finishing my first postdoc position working as a research fellow in molecular and cell biology at the University of Surrey. The project involves cloning proteins of interest and attaching them to polymers or other nanoparticles then assessing their toxicity and cellular location in liver related cell lines.

I decided to write a ‘life in the lab’ blog strand because I love working as a scientist, especially the time spent in the lab itself – despite the many challenges. It gives me a chance to share my enthusiasm for working as a researcher and all things science-related. I plan to give an early career scientist’s view of life in the lab, balancing work and childcare, procrastination and productivity, research and recreation.

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Categories: Education

The discovery of Buckyballs

31 July, 2014 - 16:31

Guest post by Rowena Fletcher-Wood

Among the many accidental discoveries through the ages is an experiment designed to probe carbon molecules in space, which unearthed a new terrestrial molecule.

Harry Kroto with buckyballs
© Science Photo Library

It all happened in an 11-day whirl, between 1 September 1985, when Harry Kroto first arrived at Rice University, US, and 12 September, when he, along with Richard Smalley and Robert Curl, submitted a paper to Nature: C60 Buckminsterfullerene’. Eleven years later, in 1996, the three were awarded the Nobel prize for chemistry.


Indeed, a Nobel prize may have been some consolation to Smalley and Curl, who were initially reluctant to delay their research on silicon and germanium semiconductors to let Kroto play with carbon. Kroto was exploring a completely different area of research: cyanopolyynes, alternating C–N chains detected in interstellar space using radiotelescopes. Although the evidence for their existence was good, the origin of these compounds was still unknown. Kroto postulated that they may form in the vicinity of red giants, and wanted to use Smalley’s laser-generated supersonic cluster beam to recreate this high-heat atmosphere and uncover mechanisms for their formation.

After agreeing to let Kroto use the apparatus, the three scientists, helped by graduate students James Heath, Sean O’Brien and Yuan Liu, loaded a graphite disk onto the beamline in a helium chamber and vaporised it into a plasma at temperatures exceeding the surface temperatures of most stars. Under high pressure helium, the vapour cooled and condensed, forming new interatomic bonds and aligning into different-sized clusters, which were immediately pulse ionised and swept into a mass spectrometer for analysis.

First, the students found Kroto’s expected carbon snakes, but then they noticed a distinct peak at C = 60 and a smaller one at C = 70. The abundance of C60, and increasing yield under higher pressure conditions suggested a very stable, closed-shell macromolecule. Unlike Kekulé’s benzene ring, buckminsterfullerene was not identified through dreaming, but through the resourceful application of sticky tape and cardboard cut outs. The model was proposed: a truncated icosahedron, consisting of twenty hexagons and twelve pentagons, like a carbon football. The name, buckminsterfullerene, was inspired by the architect famous for his similar-looking geodesic domes.

Since then, enthusiastic exploration into other fullerene allotropes has revealed that we could have accidentally discovered buckyballs long ago using much lower-tech equipment: a burning candle produces buckyballs in its soot by vaporising wax molecules. Not only that, but buckyballs occur in geological formations on Earth and, since 2010, have been detected in cosmic dust clouds. The ball-like carbon molecule wasn’t even a new idea: between 1970 and 1973, three independent research groups led by Eiji Osawa of Toyohashi University of Technology, R W Henson of the Atomic Energy Research Establishment, and D A Bochvar of the USSR, predicted the existence of the C60 molecule and calculated its stability. However, their work was purely theoretical, and didn’t get the attention it deserved. Buckyballs were discovered, rather than made, so perhaps it’s not surprising that they were found by accident: more surprising is that that weren’t found before.

 

References:

The Chemical Heritage Foundation – Richard E. Smalley, Robert F. Curl, Jr., and Harold W. Kroto

Press release – The Nobel Prize in Chemistry 1996: Robert F. Curl Jr., Sir Harold Kroto, Richard E. Smalley

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Categories: Education

Meet our guest bloggers – Rowena Fletcher-Wood

31 July, 2014 - 16:11

I am a keen science communicator, a doctoral researcher in materials chemistry at the University of Birmingham and a climbing instructor.

Most of all, I like telling stories.

When I climb, I learn to fall. When I do chemistry, I learn to look for the unexpected. I have to agree with Einstein: researchers don’t know what they’re doing, that’s what makes it research – we’re fumbling around in the dark waiting for accidents to happen, and hopefully yield good results. Some of the things we see and use every day were discovered purely by accident – some of the things I will be writing about here.

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Categories: Education

Journal cover art that will brighten your day

24 July, 2014 - 16:22

Guest post from Tom Branson

After browsing the recent chemical literature, I have finally found enlightenment. I have quite simply been left in a trance after witnessing a recent cover from Chemical Society Reviews.

A colour explosion

There’s so much colour in this image I just don’t know where to begin. So let’s start by taking a look at that green globe. Surely a prophecy of a future world when green chemistry has finally paid off and this development also seems to have led to a plethora of plant life sprouting from the Earth. Holding that planet aloft are two pairs of caring hands. An adult gently holds a child’s tiny hands and together they embrace this new future. Peace and love and chemistry, what more could you ask for?

And what about that background? Wow, they didn’t hold back with the colour palette. With some journals still charging for colour figures I bet these guys always get their money’s worth.

So there are adult hands, clasping a child’s hands, supporting the world, sprouting a bouquet of flowers, in front of a mega-rainbow, oh it’s almost enough to make me quit science and run off to join a cult.

Seriously though, the cover is a wonderful attempt to highlight sustainability and forward thinking, something that is sadly all too often lacking in modern society. The author of the paper, Jinlong Gong of Tianjin University, China, tells me of his hope that ‘this cover can call up the attention of people to consider more about the future of our world’. Nicely said.

There are not really many clues in the image as to what the published science is about but the keen eyed among you may have spotted a few water droplets on the plant leaves. Was the printer simply too close to the water cooler at Chem. Soc. Rev. headquarters, or is this paper all about solar water splitting? Aha, the latter of course.

Photocatalysis

The cover art is for a review article about a really promising solution for solar energy; tantalum-based semiconductors. Visible light can be absorbed by these semiconductors and used in solar water splitting, converting solar energy into chemical energy. The team from China highlight that while this type of photocatalyst is still far away from use in practical applications, improvements in the efficiency and stability of these systems give hope to the tantalum-based community.

Those wanting to know more about this tantal(um)ising hope for the future can access the article over at Chem. Soc. Rev.

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Categories: Education

Meet our guest bloggers – Tom Branson

24 July, 2014 - 16:00

I recently completed my PhD at The University of Leeds where I was investigating protein-carbohydrate interactions and protein assembly. I’m a synthetic biologist now working on biomolecular interactions, based in The Netherlands. I also blog about science communication issues and chemistry trivia over at Chemically Cultured.

Here at Chemistry World, I will be writing a regular blog series to highlight some of the best academic journal covers – the images that grace the front of those magazines we all paw through. Many of you might think that academic journals are a place where only serious facts and tables of data find their home, but, at the very start of many journals lies an artistic outburst.

These journal covers are a great place for researchers to highlight their work and at the same time, show off their artistic skills. Many covers have caught my eye over the years and they deserve to be promoted for the talent and, more than often, eccentricities that show in these designs. Imagination, creativity and communication are core principles in the world of science and all this comes to the fore on the front cover of our favourite periodicals.

 

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Categories: Education

YMS winners

10 July, 2014 - 14:50

The Royal Society of Chemistry’s 3rd Younger Members Symposium (YMS2014) was held towards the end of June at the University of Birmingham. Kicking off the day was Lesley Yellowlees who gave an inspirational plenary lecture covering her research and career path, in one of her final acts as RSC president. ‘Aspire to be the president of the Royal Society of Chemistry – it’s the best job ever,’ she told the audience. She also shared lessons she had learned over the years including: develop your own style, grasp opportunities and find ways of dealing with difficult colleagues.

Jamie Gallagher, the University of Glasgow’s public engagement officer, energised everyone after lunch by talking about his work and why public engagement makes you a better academic. Public engagement doesn’t necessarily have to involve standing on a stage like Jamie does on a regular basis. He gave some fantastic advice on the many schemes and organisations to get involved with such as Cafe Scientifique and your local RSC section.

Both excellent talks but the real meat of the day was comprised of poster sessions and seminars where attendees shared and quizzed each other on their research. Chemistry World was delighted to sponsor its first ever poster prizes in the inorganic and materials category. And the winners were…

First prize went to Giulia Bignami from the University of St Andrews.

Giulia Bignami: ‘The research work described in my poster focuses on the synthesis, according to the assembly-disassembly-organisation-reassembly (ADOR) method, of 17O-enriched UTL-derived zeolitic frameworks and their subsequent characterisation through 17O and 29Si solid-state NMR, involving both 1D and 2D spectral techniques, in magnetic fields ranging from 9.4T to 20.0T. We showed how 17O and 29Si NMR-based structural investigation proves extremely helpful to gain insights into the synthetic process employed, thus shedding light on the way new and targeted zeolitic structures could be achieved.’

Second prize went to Gurpreet Singh from the University of Central Lancashire.

Gurpreet Singh: ‘The aim of the research is to find new ion exchange materials for use in the nuclear industry. The problem with some of the current ion-exchange materials is that they are not stable to the conditions found in the waste pools at nuclear sites. Zirconium phosphates have been proposed to be more stable and by doping other metals into the structure in place of zirconium it might be possible to create new materials which have increase selectivity for the cations of interest (strontium and caesium). The work presented shows that yttrium can be successfully introduced into the structure of alpha-zirconium phosphate and the ion-exchange experiments are on-going.’

Third prize went to Daniel Lester for a poster about work he did at the University of Sussex.

Daniel Lester: ‘In the field of VOC (volatile organic compound) degradation by photocatalysis, P25 (powdered TiO2 of 75% anatase 25% rutile composition) is often seen as a benchmark material. However, in the continuous flow reactors used in industry, a powdered catalyst is impractical to use. I therefore aimed to create several supports for TiO2, which not only improved the physical durability of the catalyst but also improved the photocatalytic efficiency. Glass wool acted as a wave guide, TiO2 nanofibres served as photoactive supports and zeolites provided an electron sink to decrease hole-pair recombination and to increase contact time between the active species (TiO2) and the target VOC.’

Congratulations to all of our poster winners and to the organisers for an enjoyable symposium.

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Categories: Education

Open notebook science – memorial symposium for Jean-Claude Bradley

3 July, 2014 - 16:49

Guest post by Antony Williams, chemconnector.com

Jean-Claude Bradley was a chemist, an evangelist for open science and the father of a scientific movement called Open Notebook Science (ONS). JC, as he was commonly known in scientific circles, was a motivational speaker and in his gentle manner encouraged us to consider that science would benefit from more openness. Extending the practice of open access publishing to open data, JC emphasized the practice of making the entire primary record of a research project publicly available online, primarily using wiki-type environments, and in so doing set the direction for what will likely become an increasingly common path to releasing data and scientific progress to the world.

I first met JC as a PhD student at Ottawa University, Canada, when I was the NMR facility manager and was responsible for scientists and students in their research. JC entered my lab one day to ask for support in elucidating the chemical structure for one of his samples and what began that day was a scientific relationship and friendship spanning over two decades. As one of the founders of the ChemSpider platform now hosted by the Royal Society of Chemistry, JC and I reinvigorated our friendship around a drive to increase openness of chemistry data, access to tools and systems to support chemistry, and simply to make a difference.

From too many conversations I know that some of the basic tenets of his views were shunned by many scientists in the early days of his shift towards ONS. Despite people being interested in his approach only a fractional minority of scientists fully supported ONS by being active participants. Through his activities in curating and validating scientific data, engaging chemical vendors in opening some of their datasets, and his demand that everything he did in science be open, he has produced a legacy that will continue to have influence for years to come. Right now, data he released to the public domain is being worked up into open models for release to the community. The Spectral Game that he dedicated efforts to will be supported and enhanced to assist in teaching spectroscopy. In recognition of his work and to celebrate JC’s contribution to science, a memorial symposium will be held in his honour at Cambridge University on 14 July and, of course, is OPEN to everyone.

Jean-Claude Bradley was a scientific leader, an evangelist for open science and a wonderful man. He will be missed but his legacy will survive and flourish.

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Categories: Education

WebElements: the periodic table on the WWW [http://www.webelements.com/]

Copyright 1993-2011 Mark Winter [The University of Sheffield and WebElements Ltd, UK]. All rights reserved.