Numerous science-fiction books and movies have raised people's fears about nanotechnology
with scenarios such as inserting little nano-robots into your body that monitor everything you do without you realising it,
or self-replicating nano-robots that eventually take over the world.
So how do we safeguard such a potentially powerful technology?
Some scientists recommend that nano- particles be treated as new chemicals with separate safety tests and clear labelling.
They believe that greater care should also be taken with nano-particles in laboratories and factories.
Others have called for a withdrawal of new nano products such as cosmetics and a temporary halt to many kinds of nanotech research.
But as far as I'm concerned there's a need to plough ahead with the discoveries and applications of nanotechnology.
I really believe that most scientists would welcome a way to guard against unethical uses of such technology.
We can't go around thinking that all innovation is bad, all advancement is bad.
As with the debate about any new technology, it is how you use it that's important.
So let's look at some of its possible uses.