The chemist's knot challenge! Synthesize the tightest molecular knot, the future application in spinning

The synthesis of molecular knots can be said to be the beginning of the 2016 Nobel Prize in Chemistry for molecular mechanical synthesis, but so far in the 28 years, chemists have only synthesized three molecular knots. David Rey, a professor of chemistry at the University of Manchester, published the most intertwined and tightest molecular knots in the journal Science in January this year. He can further study its structural strength and have the opportunity to develop more in the future. Tough or softer thread.

Why do chemists want to fight molecular knots? Weaving and knotting techniques have always played an important role in human history, knowing how to operate these techniques can help make tough ropes, tug-of-war, or warm clothing. As technology advances, scientists are constantly researching how to make stronger, softer threads to meet the diverse needs of modern times.

If the fiber can be reinforced at the molecular scale, for example, entanglement or knotting of molecules, it is inevitably a very powerful strategy. In fact, molecular-scale knots can be found in nature, such as in organisms, where molecular knots formed by DNA (such as knots formed by replication of prokaryotic circular DNA) or in certain proteins can be found. The traces can also be found in the structure. The tightest and most complicated! Molecular junction chemists who crossed eight times have therefore attempted to artificially synthesize molecular knots using knowledge and techniques of chemical synthesis. The first success was the simplest three-leaf knot, which was developed in 1989 by a team led by Nobel Laureate 2016.