TR: When you look at the different work going on in nanotechnology, what gets you most excited?
SMALLEY: I have to admit I’m just obsessed about carbon nanotubes. It’s hard for me to go more than 10 minutes without talking about them. I think they are the coolest thing out there, and I think they’ll have the greatest likely impact. But if I break myself away from that for a moment, I believe research at what I call the wet/dry interface is intellectually most intriguing to me. It may be that in 20 years from now that is where we’ll look back and say we have made huge advances. What I call the wet side of nanotechnology is the machinery of cellular life. As we learn to interface this natural machinery with inorganic, electromechanical structures and systems engineered on the nanometer scale (the dry side of nanotechnology), vast new frontiers will be opened both in fundamental science and in practical technology.Having said that, I can come back and say that nanotubes will be tremendously important to the wet/dry interface because they bring something new to the game. Organic molecules [carbon-containing molecules that are the basis of living things] are magnificently versatile, but there are some things they can’t do well. In fact there are some things that biological systems have not yet been able to figure out, even after four-plus billion years. One thing is conducting electricity the way that metals do. Others are thermal conduction, and strength and toughness. Bones are very impressive, and so are teeth. But they aren’t steel-let alone what nanotubes can do with strength and conductivity. So, being able to take a carbon nanotube and get it into the molecular biology realm-whether it’s actually dissolved and is one of the players, or as a probe, or as part of an implant, as part of a new membrane-it’s really bringing something brand new to the table in biology. Almost an alien thing.
TR: An alien thing because…
SMALLEY: Because it conducts electricity. It brings those properties you cannot get from other organic molecules. And it’s still carbon, so it has organic chemistry. Here is an object that has, to a superlative degree, the aspects that we hold most central to the inorganic world: hardness, toughness, terrific strength, thermal and electrical conductivity. Things you just can’t do with bone and wood. But it’s made out of carbon. It’s something that plays the game at the same level of perfection as molecules and life.
There is electricity in biological systems, but it’s due to ions moving across membranes. Nerves work by electrical conduction; electric eels certainly have electricity. But that kind of electricity is different than the kind that runs in wires and houses, runs around computers, makes radios work. It’s not the kind of electricity that has to do with electrons moving in coherent fashion over long distances with little loss. That’s the property of metals, of inorganic compounds.
TR: And now nanotubes could bring this kind of electricity to biological systems?
SMALLEY: Yes. They bring to molecular biology, to the things that go bump in the night inside a cell, a new toy to play with-something that conducts electricity.
TR: What will the new toys be?
SMALLEY: Stay tuned for the next millennium and we’ll see. I could give some examples, but they’d seem rather pedestrian and ad hoc. Up until you add something like this to the mix, there is no way that the incredible machinery of living cells can construct something that can conduct electricity with the efficiency of metals. Here we have an [organic] molecule that can do that. I don’t believe anyone is bright enough to predict the vast implications of that. But Lord knows how many years it will be before nanotubes are part of living cells. Before that, we can use nanotubes as probes into cells, as probes to detect the structure of molecules, to sequence DNA. These are wonderful new wires to do that.