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Their inventions include a tiny lift, artificial muscles and miniscule motors
The 2016 Nobel Prize for Chemistry has been awarded to three scientists— Jean-Pierre Sauvage University of Strasbourg, France, Sir J. Fraser Stoddart of Northwestern University, USA and Bernard L. Feringa University of Groningen, the Netherlands for developing the world’s smallest machines—molecular machines.
Molecular machines are molecules that are designed to move controllably and perform a task when energy is added.
The first step towards a molecular machine was taken by Frenchman Jean-Pierre Sauvage in 1983, when he succeeded in linking two ring-shaped molecules together to form a chain, called a catenane. Normally, molecules are joined by strong covalent bonds in which the atoms share electrons, but in the chain they were instead linked by a freer mechanical bond. For a machine to be able to perform a task it must consist of parts that can move relative to each other. The two interlocked rings fulfilled exactly this requirement.
The second step was taken by Fraser Stoddart in 1991, when he developed a rotaxane. He threaded a molecular ring onto a thin molecular axle and demonstrated that the ring was able to move along the axle. Among his developments based on rotaxanes are a molecular lift, a molecular muscle and a molecule-based computer chip.
Bernard Feringa was the first person to develop a molecular motor; in 1999 he got a molecular rotor blade to spin continually in the same direction. Using molecular motors, he has rotated a glass cylinder that is 10,000 times bigger than the motor and also designed a nanocar.
Describing these incredible inventions, the Royal Swedish Academy of Sciences noted in its press release that the three scientists had “taken molecular systems out of equilibrium's stalemate and into energy-filled states in which their movements can be controlled”.
It added further: “In terms of development, the molecular motor is at the same stage as the electric motor was in the 1830s, when scientists displayed various spinning cranks and wheels, unaware that they would lead to electric trains, washing machines, fans and food processors. Molecular machines will most likely be used in the development of things such as new materials, sensors and energy storage systems”.