general chemistry

The advance of the chemical-free sciences

Chemist have long complained about the use of the term ‘chemical-free’ in marketing, particularly when used to promote organic produce. To bolster our standing, and to sure up the chemical industry, we go one about everything containing chemicals and hence  how ‘chemical-free’ is a meaningless term.

The veracity of the anti-chemical-free movement is highlighted by continuing complaints to the advertising standard agency on the grounds that ‘chemical-free’ is a misleading term. None of these have not been upheld. Meanwhile campaigners have continued the fight by produced numerous posters detailing the chemical composition of natural products, apparently to highlight the absurdity of the term.

However, there is a growing group of dissenters on the other side of the fence. They believe it is perfectly possible to manufacture a ‘chemical-free’ product. Not only have they long been developing such materials, but they have been slowly drip feeding their findings into the scientific literature. The result is that  there is now a significant amount of material that can no longer be ignored by the mainstream. Almost 4,000 peer-review papers exist reporting the existence of chemical free products and these include publications from the American Chemical Society and the Royal Society of Chemistry.  Furthermore technical advances have lead to many patents describing chemical-free methods, thus demonstrating practical applications of the science and how it can be turned into workable technologies, all without the need of chemicals.

These findings must now surely lead the  Royal Society of Chemistry to deliberate on now it is going to distribute the  £1 million it offered  for a verifiable chemical free product. Used wisely the money could fund research into further chemical-free technologies.

Clearly the chemical-free sciences are growing, and there are claims that it may well be the scene of future groundbreaking technologies. Its bound to represent the next big idea or buzz word, to sit alongside nanotechnology, synthetic biology and homeopathy in newspaper columns and grant applications alike. So maybe the RSC should consider using its £1 million to fund a new Journal of Chemical-Free Chemistry, plus related conferences so that this up-and-coming field can blossom out in the open.

 

By April 1, 2014 11 comments fun, general chemistry, opinion

Wellcome chemical images

The UK’s leading medical research charity, the Wellcome Trust, have donated a treasure trove to the world; 100,000 images covering the history of all aspects of medicine, science and technology are now freely available to any and all.

The database contains pictures of weird and wonderful medical instruments, copies of historical documents and stunning examples of science related works of art from Van Goghs to cartoons. It’s a joy just to peruse the library jumping from one fascinating image to the next. But, being a chemist, I was of course, particularly drawn to the documents and apparatus depicting the history of my chosen field.

Take the paraphernalia of the great and the good which gives a wonderful insight into their lives, working habits and personalities.

Of course Watson and Crick are well represented. There’s the draft of their famous paper describing the double helix of DNA, complete with hand written notes and annotations. But a better testament to Crick’s temperament and modesty is a photo of some graffiti allegedly scrawled by him. It seems to be part of a exchange with Enoch [Powell?] whilst also suggesting Crick may have had ambitions beyond a mere Nobel Prize.

Francis Crick’s graffiti, date unknown

Francis Crick wall graffiti Credit: Wellcome Library, London. Wellcome Images images@wellcome.ac.uk http://wellcomeimages.org Francis Crick wall graffiti, Location and date unknown 'Keep the Lefties Out. Crick for God' Crick Papers Published:  -  Copyrighted work available under Creative Commons by-nc 2.0 UK, see http://wellcomeimages.org/indexplus/page/Prices.html

Credit: Wellcome Library, London. Wellcome Images
Copyrighted work available under Creative Commons by-nc 2.0 UK,

 

There’s plenty of material on double Nobel Laurette, Marie Curie. Images of her laboratory are fascinating insight into her practices.

However, it’s her scruffy laboratory notebook that I find most interesting. Madam Curie was certainly a genius but her notes probably won’t pass muster with most PhD supervisors today.

Pages from Marie Curie’s notebook 27 May 1899 – 4 December 1902 

redit: Wellcome Library, London. Wellcome Images images@wellcome.ac.uk http://wellcomeimages.org Page from notebook. 27 May 1899 - 4 December 1902 Holograph note-book containing notes of experiments, etc. on radio-active substances. Marie Curie Published:  -  Copyrighted work available under Creative Commons by-nc 2.0 UK, see http://wellcomeimages.org/indexplus/page/Prices.html

Credit: Wellcome Library, London. Wellcome Images
Copyrighted work available under Creative Commons by-nc 2.0 UK

 

Then there’s the equipment that highlights how science has progressed.

Take the X-ray spectrometer lovingly developed by the Leeds physicist William Henry Bragg. The 100 year old device is  the direct ancestor of equipment housed at synchrotron like the massive Diamond light source.

Bragg’s X-ray Spectrometer 1910-1926

Bragg X-ray spectrometer, England Credit: Science Museum, London. Wellcome Images images@wellcome.ac.uk http://wellcomeimages.org Bragg X-ray spectrometer, England, 1910-1926 Developed by William Henry Bragg (1862-1942), a professor of physics based in Leeds, England, this X-ray spectrometer was used by him and his son William Lawrence Bragg (1890-1971) to investigate the structure of crystals. The Braggs developed new tools and techniques to understand crystals. Their research was the basis of ¬X-ray crystallography, a technique that was used to advance chemistry, physics and biology. The Braggs won the Nobel Prize for Physics in 1915. 1910-1926 Published:  -  Copyrighted work available under Creative Commons by-nc-nd 2.0 UK, see http://wellcomeimages.org/indexplus/page/Prices.html

Credit: Science Museum, London. Wellcome Images
Copyrighted work available under Creative Commons by-nc-nd 2.0 UK

Or the penicillin fermentation vessel, one of thousands originally used by Glaxo (now GlaxoSmithKline) to grow the penicillium mould from which the antibiotic was extracted. Later the mould was grown in fermentors. Now of course the antibiotics are made synthetically.

Penicillin fermentation vessel, 1940-45

Credit: Science Museum, London. Wellcome Images images@wellcome.ac.uk http://wellcomeimages.org Penicillin fermentation vessel, England, 1940-1945 Thousands of glass fermentation vessels like this one were used in Glaxo (now GlaxoSmithKline) laboratories to produce penicillin. The penicillium mould was grown on the surface of a liquid filled with all the nutrients it needed. This approach was superseded by the method of growing the mould within large industrial fermenters. The antibiotic was first used in the early 1940s and saved the lives of many soldiers during the Second World War. 1940-1945 Published:  -  Copyrighted work available under Creative Commons by-nc-nd 2.0 UK, see http://wellcomeimages.org/indexplus/page/Prices.html

Credit: Science Museum, London. Wellcome Images
Copyrighted work available under Creative Commons by-nc-nd 2.0 UK

And there’s a wealth of early infographics, like this table of chemical characteristics from 1799, which predates the modern periodic table and chemical notation. Instead the elements (along with light and combustion) have been given symbols which are then combined to represent the compounds formed when these element are reacted together. The result is a beautiful if confusing representation of the state of chemistry in the 18th century.

 

Chemistry: symbols of elements and substances. Coloured engraving by H. Ashby, 1799, after W. Jackson. 

Chemistry: symbols of elements and substances. Coloured engr Credit: Wellcome Library, London. Wellcome Images images@wellcome.ac.uk http://wellcomeimages.org Chemistry: symbols of elements and substances. Coloured engraving by H. Ashby, 1799, after W. Jackson. 1799 By: William Jacksonafter: Henry AshbyPublished: 26 October 1799 Copyrighted work available under Creative Commons by-nc 2.0 UK, see http://wellcomeimages.org/indexplus/page/Prices.html

Credit: Wellcome Library, London. Wellcome Images
. Coloured engraving by H. Ashby, 1799, after W. Jackson.
1799 By: William Jacksonafter: Henry AshbyPublished: 26 October 1799
Copyrighted work available under Creative Commons by-nc 2.0 UK

Finally the mundane but no less fascinating. How about a cunning 3D representation of the periodic table lovingly mounted in a jam jar!

L0002952 Model showing Periodic Elements of Chemistry Credit: Wellcome Library, London. Wellcome Images images@wellcome.ac.uk http://wellcomeimages.org Model showing Periodic Elements of Chemistry. From a model prepared at the Royal Institute of Chemistry Published:  -  Copyrighted work available under Creative Commons by-nc 2.0 UK, see http://wellcomeimages.org/indexplus/page/Prices.html

Credit: Wellcome Library, London. Wellcome Images From a model prepared at the Royal Institute of ChemistryCopyrighted work available under Creative Commons by-nc 2.0 UK 

 

This post originally appeared in the Guardian.

By January 30, 2014 1 comment general chemistry

Molecule of the day with a difference

Everyday Zoë Waller posts a drawing of a molecule on her twitter feed. A quick trawl pulls up others who do similar.  But Zoë’s uses a rather unusual canvass … herself. She doesn’t graffiti herself with ink, instead she takes advantage of her unusual skin.

 

Zoë has dermatographia, a condition which results in her skin releasing histamines  in response to physical pressure. This manifests as an apparent mild allergic response, with localised swelling when she scratches herself.  The effect fadesafter about 30 minutes, but that’s plenty of time to use a her favourite bamboo skewer, or tablet stylus to doodle a molecule on her skin.

 

And the results are fascinating insight into the molecules that Zoë, as a chemical biologist comes across.

 

There’s allicin the molecule responsible for garlic smells.

Allicin

 

Capsaicin for those that like it hot,

 

Capsaicin

 

and lycopene, the red pigment from tomatoes

 

Lycopene

She’s also done macromolecules,

 

SP1, transcription factor

 

or the intricate oxytocin.

 

Oxytocin

 

And, many, many more.
Make sure you follow Zoë’s tweets for daily updates. And she even does request.
By January 26, 2014 1 comment general chemistry

Frederick Sanger, 1918-2013

This week Fred Sanger died at the age of 95. His name is probably unfamiliar to most, but he is considered one of the greatest chemists of our age. He is the only person to have won two Nobel prizes for chemistry (only three others have won two Nobel prizes – Marie Curie, Linus Pauling and John Bardeen).

Sanger’s lack of fame is in no small part due to his humble nature and modesty. His sole autobiographical article, written five years after his retirement, starts with the self-deprecating comment: “I was not academically brilliant”. But there is no false modesty here, the article makes no mention of the numerous prizes and honours bestowed on him. These included a knighthood which he turned down, not for any moral objection to the honours system, but because he did not like the idea of being addressed as “Sir”.

Sanger spent his career studying the three fundamental polymers of life – proteins, RNA and DNA. It had long been known that DNA and RNA were made up of strings of just four bases, while proteins are more complicated, consisting of strings of 20 amino acids. However, just knowing this is like understanding that sentences are made of letters but having no idea what order the letters come in. Sanger strove to decipher the order of DNA and RNA’s bases and protein’s amino acids.

Other great (and many familiar) names such as Francis Crick, James Watson, Rosalind Franklin and Max Perutz worked on the 3D structures of these molecules. But Sanger’s work was more fundamental and arguably more useful – he laid the bedrock on which some of the greatest achievements of 21st century science such as the Human Genome Project and all that has followed were built.

Third from right: Sanger at the British Genius Exhibition at Battersea Park. PA

Sanger started his research career in 1943 on proteins. His Quaker upbringing led him to be a conscientious objector, so he was excused from fighting in World War II. He chose to work on insulin, partly because of its medical importance, but also for the practical reason that he could buy it at the local drugstore. It took him 12 years of work in a laboratory to come up with a solution. This dogged persistence and daily lab work characterised his scientific career:

Of the three main activities involved in scientific research, thinking, talking and doing, I much prefer the last and am probably best at it. I am all right at the thinking, but not much good at the talking.

After this success Sanger entered a period that he described as “lean years with no major success”. He had some sage advice on how to deal with these periods that affect many careers, not just scientific ones:

I think these periods occur in most people’s research careers and can be depressing and sometimes lead to disillusion. I have found the best antidote is to keep looking ahead. When an experiment is a complete failure it is best not to spend too much time worrying about it but rather get on with planning and becoming involved in the next one. This is always exciting and you soon forget your troubles

This quote speaks volumes about his values as during this “lean” “depressing” period Sanger was awarded, for his work on insulin, one of his Nobel Prizes.

This period came to end when Sanger began work on sequencing RNA and DNA. In 1971, state-of-the-art science had managed to determine the sequence of a stretch of DNA just 12 bases long (not much use considering the human genome consists of 3 billion bases). By 1978 Sanger had extended the record to 5,386 bases and then to 48,502 bases by 1982. These advances demonstrated that it was now possible to sequence vast stretches of DNA. It was for this work that he was awarded his second Nobel Prize, in 1988. But, probably of more value to Sanger was the knowledge that the DNA sequencing he developed made the global Human Genome project (instigated in 1990 and involving thousands of scientists) possible.

As far as Sanger was concerned, his DNA sequencing method was the climax of his career – and so at the age of 65, at the top of his game, he retired and gave up research. Retiring at 65 may not seem odd, but its is rare for a top scientist where a lifetime spent single-mindedly pursuing knowledge is a hard thing to give up.

Sanger was different. He felt the need for a lifestyle change and heeded the call of his rose bushes. He also wanted to make space for younger scientists, many of whom, through his nurturing, went on to win their own Nobel Prizes. So for the next 30 years he focused on his gardens in Cambridge, never once revelling in the glory that was so rightfully his.

This article was originally published at The Conversation.
Read the original article.

By November 21, 2013 0 comments general chemistry, science news