This afternoon's session was one that leapt out of the (shoulder-destroying 2.4 kg) abstract book: Molecular Machines and Devices. Itamar Willner, Alan Rowan, Dirk Guldi, Lee Cronin and Harry Anderson. Some line-up! And all tucked away in a just-about-big-enough room in the depths of the conference venue.

Without wishing to summarise everything, I'm going to pick on the two talks I enjoyed most: Alan Rowan's and Lee Cronin's.

Alan Rowan covered his work trying to understand how long chain molecules thread through macrocycles - as an analogy to DNA polymerase. The macrocycle can be a catalyst that epoxidises double bonds, so being able to do it an controlled way would be very useful. Unlike the enzyme, it just hops about attacking double bonds almost at random. They've studied a non-catalytic macrocycle and found out all sorts about how the length of the chain and the size of the macrocycle affects things. I started to wonder if you could make a macrocycle with a variable aperture and control things that way - anyone got any ideas how to do that??

Lee Cronin's talk had tons of videos - ranging from 'cartoon' simulations of the insides of the polyoxometalate (POM) cavity materials his group makes. As he said, they were a little big of a rollercoaster ride and I found myself wishing I was sitting further away from the screen at one point! But they did emphasise the cavernous space inside these things - 'like a cathedral', as Cronin said. The other videos were actual films (through a microscope) of the microtube growth from POM crystallites, as reported in our own issue 1 (free to read!). The ones where the growth could be controlled and played about with went down very well. He finished off with some some videos of 'bags' of these materials, acting almost like little reaction vessels - the colour change of a potassium permanganate solution was very striking.

The theme continued with the Plenary from Ben Feringa, with an amazing array of molecular machinery. I'll leave you with some of his closing thoughts: Will we one day have nanomachines in our bloodstream, delivering drugs and tidying up our arteries? He doesn't know, but was optimistic, because today's chemist has a lot more available to him/her than nature did - we're not limited to amino acids, for a start!

Neil

Neil Withers (Associate Editor, Nature Chemistry)