It was one of the biggest medical scandals of the 20th century: the drug Thalidomide, prescribed in the 1960s to treat morning sickness in pregnant women, turned out, tragically, to cause serious birth defects in their babies.
Emily Xu, this year’s winner of the GSK UK Young Scientist of the Year award, explains why taking the drug resulted in such a catastrophic outcome: “Thalidomide is a chiral molecule, which means there are two versions: a ‘right-handed’ molecule and a ‘left-handed’ one, which are mirror images of each other,” she says. “While one mirror image worked to reduce the morning sickness, the other caused the birth defect. There are many other drugs where mirror-image molecules (or enantiomers, as they are more properly known) present a problem – but currently there isn’t a cheap and easy way of separating them.”
A student at James Allen’s girls’ school in Dulwich, Xu, 18, won the prestigious award for her work on mirror-image molecules. In the process, she saw off hundreds of other high-calibre entrants to the annual competition, which is open to students aged between 11 and 18. As well as receiving a prize of £2,000, a tour of the GSK labs and an annual pass to the Science Museum Wonderlab, Xu will act as an ambassador to inspire the younger generation to pursue careers in science, technology, engineering and mathematics (Stem). At a time when the UK is short of Stem specialists, the award plays an important part in showcasing scientific talent and highlighting Stem’s importance in a modern, knowledge-based economy.
So how did Xu manage to beat more than 200 other finalists to take the title? Her project involved exploring ways to separate mirror-image molecules using metal-organic frameworks (MOFs) – relatively new materials, created in the 1990s by combining organic and inorganic molecules. MOFs, as they are known, have generated a good deal of excitement in the scientific community because of their range of potential uses, including extracting hydrogen from air for use as a sustainable fuel.
Although she’d always enjoyed science in school, and is taking A-levels in chemistry, physics, maths and further maths, Xu’s interest in MOFs was sparked by seeing a programme about how they could be used to purify water, using much less energy than traditional methods. This interest led to her winning a five-week Nuffield Research Placement at Imperial College London’s chemical engineering department in summer 2017, working with a PhD student.
Xu explains: “My project was based around separating chemical molecules that are mirror images of each other – they’re like your left and right hand. Although they’re chemically and physically identical, you can rearrange them however you like and they’ll never be superimposable on each other. It’s important to separate these chemicals, because lots of drugs are made up of these mirror images, and when you ingest them, one of the mirror images can react in one way and the other mirror image can react in a different way, and that can be either inefficient or potentially dangerous.”
Thalidomide, she says, is one such example. Ibuprofen, on the other hand, is an example that is simply inefficient: only one of the mirror images works to reduce the pain. Although methods exist to separate the mirror images, they are expensive. MOFs “have a larger potential to separate the mirror images in a much more economical way”.
The project she worked on at Imperial involved conducting experiments to see “how efficiently the MOF was able to absorb and separate a particular enantiomer from its counterpart”. When you create an MOF, explains Xu, it’s “like baking a cake – you have different ingredients, and you’re changing the ingredients to see how this affects the structure of the MOF, and how that in turn affects how it is able to separate one mirror image in preference of another mirror image.” This is important, she adds, because it could enable pharmaceuticals companies to separate mirror-image molecules to produce safer and more efficient drugs more cost-effectively – ultimately bringing down the price of medicines and “making them more accessible worldwide”.
Having sailed through the online heats of the GSK UK Young Scientist of the Year competition, Xu was invited to the Big Bang Fair finals in Birmingham, a four-day annual event celebrating science and technology that attracts 20,000 visitors a day. Along with the other finalists, Xu had to explain her project both to visitors to the fair and to the judges – not easy, given its technical nature. Luckily, she had her dad to test it on: “My dad has no science background whatsoever, so I just kept practising to him, trying to explain it in layman’s terms so everyone would understand it.”
It clearly paid off, and winning the award has increased Xu’s conviction that she would like a career in research, further exploring the potential of MOFs. She has been offered a work placement at GSK’s research labs this summer and after that she hopes to take up a place to study chemical engineering at Imperial. Nikki Yates, senior vice-president, GSK Europe, says: “I’m excited to see what Emily and the other finalists will go on to achieve in the years to come.”
In the meantime, Xu says she is looking forward to her role as an ambassador for Stem: “One key thing I have learned this year is to follow your interests and take every opportunity that comes your way.”
