麻豆传媒

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During the industrial revolution, simple mechanisms like pistons and ratchets were combined to produce machines that could do the work of many people. The changes this brought were both positive and negative, but nobody denies how sweeping they were. It might be wise to keep that in mind today, as chemists develop molecular machines 鈥� devices made not of iron, but of atoms 鈥� which could be as disruptive as any steam engine.

Simple molecular machines have existed for about two decades. Early examples include molecular wheels that could move along an axle, creating a piston-like mechanism. Three pioneers of this work 鈥� Fraser Stoddart at Northwestern University in Illinois, Ben Feringa at the University of Groningen in the Netherlands and Jean-Pierre Sauvage at the University of Strasbourg, France 鈥� were recognised with a Nobel prize in 2016.

More useful machines are now being made and tested. A few years ago, James Tour at Rice University in Houston, Texas, and his colleagues created a molecular machine that could . This allows it to open holes through which drugs could be delivered.

Such devices can be built on to create even more sophisticated machines. The potential is huge: after all, living things use biomolecular machines to do many useful jobs. Ribosomes, for example, are biomolecular machines that assemble proteins. They add molecules called amino acids together in specific sequences to create a vast array of amazing materials, from the keratin in fingernails to the disease-busting antibodies of our immune systems.

鈥淢olecular machines are going to change everything in terms of material design鈥�

, UK, has long been working on a synthetic version of the ribosome. His designs tend to be based on a ring-shaped molecule equipped with an 鈥渁rm鈥� that moves along a linear molecular track, picking up pieces along the way and joining them together. Last year, Leigh and his team , in a specific sequence.

For the moment, Leigh鈥檚 machines can鈥檛 go beyond what nature can do. But that could change. Ribosomes only build with about 20 amino acids, but a synthetic ribosome could be designed to work with a far wider range of molecules. 鈥淲e can use the whole of the periodic table,鈥� says Leigh. 鈥淚 think molecular machines are going to change how we do everything in terms of material design.鈥�