he 1980s sci-fi film Innerspace sees a submersible
and its pilot shrunk to microscopic size before
being jabbed into a shop attendant, and much
hilarity ensues. The plot took its inspiration from 1960s
classic Fantastic Voyage, in which a miniaturised crew are
injected into a dying scientist and must attempt to remove a
clot from his brain.
Both films seemed pretty crazy when they came out, but
the extraordinary ideas featured no longer seem quite so
far-fetched. Tiny cameras can now be swallowed, while
electrodes can be placed deep within the brain. A nd
increasingly, nanotechnology tiny enough to be injected
into the bloodstream is the focus of new treatments for
diseases like cancer.
These ingenious devices are expected to revolutionise
medicine in the coming decade – they’re small enough to
f low through the body’s tiniest blood vessels, yet are packed
with technology smart enough to find and treat the causes
of diseases. PHOTO: KOBAL COLLECTIONT
SMALL SCIENCE
The simplest nanomedicines are spherical particles that
carry a payload of drugs. Smaller than human or bacterial
cells, but larger than individual molecules, the spheres are
tiny enough to penetrate cells. The term ‘nano’ is used to
describe objects smaller than 100 nanometres, with one
nanometre being a billionth of a metre. Particles at this
scale have dif ferent proper ties than if they were larger.
Nanomedicines are large enough to stay in the
bloodstream for longer than normal medicine molecules,
yet they are not so big that they clog up blood vessels.
Scientists can even attach biological molecules to the
outside of nanoparticles to ensure, for example, that they
are attracted to specific molecules in the body – such as
those found in tumours. Or, by making nanoparticles with
more complex shapes, scientists can effectively create tiny
machines that use chemical reactions to become
unimaginably small motors or light-emitting globes. SomeABOVE:
The plot of sci-fi
film Innerspace no
longer seems quite
so outlandishSCIENCE