Category Archives: history

Colour Changing Chalice

Not only a tongue twister, this colour changing chalice left scientists in knots as they struggled for decades to understand how it worked. Known as the Lycurgus Cup, it is both the only  figural example of a type of vessel known as a ‘cage-cup’ and the only complete Roman glass object made from dichroic glass.
Lycurgus Cup is made of dichroic glass and appears jade green when lit from the front. © Trustees of the British Museum

Lycurgus Cup (4th century AD) is made of dichroic glass and appears jade green when lit from the front. © Trustees of the British Museum

What is so fascinating about this chalice is that is changes colour depending if light is shone from the front or back. This colourful secret intrigued scientists and it wasn’t  until 1990 they attributed this colour change to nanotechnology.
The Roman artisans “impregnated the glass with particles of silver and gold, ground down until they were as small as 50 nanometers in diameter, less than one-thousandth the size of a grain of table salt.”  When light hits the metal nanoparticles, the electrons in the metal are excited in ways that alter the colour depending on the observer’s position.
Lycurgus Cup is made of dichroic glass and appears blood red when lit from the back. © Trustees of the British Museum

Lycurgus Cup is made of dichroic glass and appears blood red when lit from the back. © Trustees of the British Museum

I stumbled upon this beautiful chalice in a recent Smithsonian Magazine article as it seems scientists are tamping into this 1,600-year-old “technology” to create “super­sensitive new technology that might help diagnose human disease or pinpoint biohazards at security checkpoints”.
If you’re like me and want to see the real thing you need to get yourself down to the British Museum.

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Science History as Art

I’ve been walking along the corridors at HHMI’s Janelia Farm, wondering what lots of the beautiful sci-art pieces were based on (I think many are actually to do with fly brain scans and other neuroscience research since that’s what the facility is known for – such a shame they don’t label any of them).

Mosaic portraits of renowned scientists by Julie Simpson and Frank Midgley.

Mosaic portraits of renowned scientists by Julie Simpson and Frank Midgley.

Anyway, the above series of mosaics caught my eye – they were “assembled from Google search images of key research terms”.  Here is more  on how they were curated.

A Colourful Success in Medicine

I’d like to share this video with you (I love it so much I have posted it twice on my Twitter account, so I have to apologise if you follow me and are fed up with this link).

You may be thinking, “you’re not a surgeon, so why are you so excited by this?”, well although I think Quyen Nguyen is working on a fantastic idea for cancer surgery, my reason for liking this video is more of the historical link between colour and medicine.

I remember when I first learnt about William Perkin in A-Level chemistry and to this day I am still so impressed by how one man’s accidental discovery influenced many facets of our society.

In 1856, the only viable antimalarial drug was quinine, and with its demand beginning to surpass its available supply, an 18-year-old William Perkin set out to try to make it synthetically, using the waste product coal-tar. Perkin’s synthesis didn’t go quite to plan and he was instead left with a black sludge which he later refined into a vivid purple hue. Being the shrewd person he realised its potential as a textile dye and knew not to discard this discovery. He later named this colour mauve and it became known as the first synthetic dye. After patenting his dye Perkin set up a factory in Greenford Green (London, UK) with his father and brother. With Queen Victoria and Empress Eugénie of France seen to endorse the colour, “mauve mania” spread and commercial success was soon achieved.

William Perkin holding a sample of fabric dyed with his chemical discovery: mauve.

William Perkin holding a sample of fabric dyed with his chemical discovery: mauve.

Perkin’s discovery is remarkable not only because it had an impact on fashion and society (working class people could readily afford colourful textiles), it also led to further developments in synthetic colours, playing a huge role in medicine – the staining agent methylene blue was used by Koch to discover the bacilli of tuberculosis and cholera; and (one which I’m sure Perkin himself would be happy about) this same agent was shown by Ehrlich to have antimalarial properties. Perkin’s discovery also created further interest in organic chemistry which is still at the heart of today’s pharmaceutical industry.

The video above is just one example of how synthetic dyes are still playing a role in medicine and biomedical research. I love the back story – after all, who would have ever thought that the advancements in fashion and medicine were so closely linked!