This is them is new ways to tie knots. There are more than 6 billion different types of knots that have been

tabulated by mathematicians, 6 billion.

David Lee, a chemist at the University of Manchester in the UK.

The hard party says is actually making them.

Just because I can see a knitted jumper

doesn't mean that I can actually make one.

Because what Lee and his colleagues are interested in

is tying molecular knots,

using strands that are 10,000 times thinner than a human hair.

With a molecule, you can't just grab hold of the ends and tie them like you with a shoelace. They're too small for that and

instead you've got to use chemistry to make the molecules sort of fold themselves round

into the precise way that you need to form the

particular knot. Continuing the shoelace analogy, remember when you were learning to

tie your shoes, your mom or dad put a finger in the middle of the nut to make it easier to tie?

Well, Lee and his team did something similar, but they used metal ions as the fingers to keep the knot tying organized. Then tiny molecular strands,

just 192 atoms long, assembled themselves around the ions. And then mom pulls a

finger out and we extract the metal lines out and you're left just with the

knot at the end.

The most complex molecular knot ever synthesized, the studies in the journal Science. Now knots were hugely useful to our ancestors in the stone age.

Fishing nets and axes with blades tied to the handles and how to weave fabrics to keep him warm.

And Lee says knots could be just as helpful in the molecular world,

like for stronger braided polymers,

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