The tightest knot ever is also one of the tiniest. Made of strings of molecules braided together, the knot is only 20 nanometres long, and its properties are as yet unknown. But researchers hope that these tied-up molecules could lead to lighter body armour or more flexible surgical sutures. Molecular knots like this are probably more analogous with the knots in mathematics, which are closed loops twisted into different shapes, than with the knots in your phone charger's cord. The first molecular knot – one of the most mathematically simple kinds called a trefoil knot – was tied in 1989.

January 17, 2017 --Knots have been around for thousands of years. But now, a team of researchers from the University of Manchester has added a new twist to one of the most basic technologies known to humans. Using cutting-edge chemical techniques, the researchers have created the tightest knot ever made, woven on a molecular level. The new knot is a circular triple helix only 20 nanometers long, containing only 192 atoms, the researchers report in a paper published in the Jan. 13 issue of Science magazine. While scientists have known for decades that molecular knots like this one are theoretically possible, it has proven difficult to create knots of such complexity, with previous molecular knots using only two strands woven together in very basic patterns.

Trying to knot tiny molecules together is a task that is exactly as difficult as it sounds. However, manipulating molecules into ever tighter knots is a goal that many researchers eagerly pursue, and not just for the daunting challenge it provides. Scientists believe that making different types of molecular knots can be used as a method to probe how knotting affects strength and elasticity of materials. This, in turn, can lead to the creation of polymer strands that can be used to build stronger and more flexible materials. A team of researchers from the University of Manchester has now created a record-breaking knot.

The 2016 Nobel Prize in chemistry has been awarded for the design and synthesis of the world's smallest machines. The work has overtones of science fiction, but holds huge promise in fields as diverse as medicine, materials and energy. This is especially true of efforts to develop nano-scale machines (1,000 times smaller than the width of a human hair), which are always destined to remain tiny however big our ambitions for them grow. It's difficult to trace the development of molecular machines to one person or scientific step. But a 1959 lecture by the celebrated physicist Richard Feynman is as good a point as any.

Alfred Nobel wanted the prizes that bear his name to recognize achievements that offered the "greatest benefit to mankind." The world's tiniest machines -- celebrated in this year's chemistry prize -- may revolutionize daily life. The Royal Swedish Academy of Sciences on Wednesday awarded the final Nobel prize in sciences for 2016. The 8 million kronor ( 930,000) chemistry prize went to Jean-Pierre Sauvage of France, Sir Fraser Stoddart of Britain, and Bernard "Ben" Feringa of the Netherlands. The scientists were recognized for their breakthroughs on molecular machines, which began with Dr. Sauvage linking two ring-shaped molecules in 1983.