Sir Fraser Stoddart shared this year’s Nobel Prize in chemistry for constructing tiny molecular machines based on the remarkable phenomenon of self-assembly, a process by which forces between atoms automatically pull diverse molecules together into precise geometric configurations without having to explicitly position them this way. These machines represent much promise for the field of nanotechnology, especially when we figure how to harness the mechanical forces in these molecules to perform specific functions like making copies of themselves, killing cancer cells or building other molecular materials. The Nobel Prize that Stoddart shared with fellow chemists Ben Feringa and Jean-Pierre Savage comes at the pinnacle of entire careers spent patiently exploring the structure and function of these molecular architectures.
One of the many interesting objects Stoddart created in the laboratory was a Borromean ring, a structure which had been mathematically conceived for some time but not physically realized until 2004 when Stoddart and his group chemically synthesized it. From a mathematical standpoint a Borromean ring is a good example of an object from the field of knot theory. It is a complex knot consisting of several interlocking rings. The special property of these rings is that you cannot cut any of them without having the entire structure break apart. From a chemical standpoint the Borromean ring is a tantalizing example of self-assembly, a process in which the individual molecules making up the ring simply ‘find’ each other and assemble; the chemist has to merely make the individual building blocks.
|The first molecular Borromean ring: 18 individual
molecules automatically self-assembly under the right conditions
Stoddart described the discovery of these Borromean rings in a talk given six years ago at the Institute for Human and Machine Cognition in Florida. The choice of the venue would be unusual were it not for the futuristic promise of molecular machines in improving human life, a goal also shared by the field of artificial intelligence. The entire talk is worth watching, but one part of the story which really stood out for me was a moving tribute by Stoddart to his wife Norma Stoddart who passed away from breast cancer in 2004. The tribute was not just moving but it also illustrated the classic yin and yang quality of life, with black clouds and silver linings. As Stoddart recounts, the breakthrough in designing the first Borromean ring was very much a sorely needed silver lining, not just because it came after a year of failures in deciphering the structure of these elusive molecules, but because it came at the end of receiving a tragic piece of news.
“It’s all part of life’s rich fashion. It’s not all a bowl of cherries. She was a brilliant scientist, much more able than I. She succumbed to breast cancer, and she fought that disease like no one’s business for 12 years. She became known, ironically, as the little iron Englishwoman of Santa Monica. So that was Black Tuesday, it was the day that her oncologist said to me that the fight was over because the cancer had metastasized to her brain, and she always said that if that happened the fight would be over. So I came back to the lab from the clinic feeling quite low, and there was the structure of the Borromean Rings. So as they say, every black cloud has a silver lining.”
Stoddart clearly enjoyed a very close relationship with his wife, and anyone who has lost a close spouse must know how incredibly hard and unique the pain is. Here’s something that struck me: compared to the tragedy of losing a loved one, a specific scientific discovery might seem to provide negligible succor. And yet science has always been an amazing source of strength and certainty in tumultuous times, and this is one of its supremely important and reassuring qualities. Whether one is talking about European physicists finding refuge in the field of quantum mechanics during the politically fraught 1930s or, on a very personal level, a scientist finding refuge in the glow of scientific discovery in the shadow of a personal tragedy, this kind of novelty and joy in discovering new facts of nature is one of the things that makes science so much worthwhile. By recounting this moving story, Stoddart demonstrates not just the joy of science but its quintessential quality as a human endeavor. It is a triumph of the spirit over both scientific and personal hurdles. Thank you, Fraser Stoddart.