NANOTECHNOLOGY—TECHNOLOGY ON A MOLECULAR SCALE - Chemistry: Notable Research and Discoveries - page 63

Like most of the techniques described in this chapter, these medical
procedures are still in the experimental stage. New medical treatments
always require extensive testing before physicians widely adopt them,
and a considerable amount of time may elapse before these techniques
move from the laboratory to the hospital. But the potential for tremen-
dous advances in medicine is clear.
ConCluSIon
Much of chemistry occurs at small scales. As Dalton and other scientists
realized, atoms are the basic units of matter and combine chemically
to form molecules. Although chemists usually work with substantially
larger amounts of matter, researchers in the field of nanotechnology
are beginning to develop the techniques to manipulate matter on the
atomic and molecular scale. By finding the right conditions in which
atoms and molecules will assemble into functional structures, or by
constructing tiny machines that oscillate, researchers have entered the
domain of the atom.
Nanomaterials for medical applications have been found, but re-
searchers' ambitions extend well beyond this. Most diseases are detected
only after they have gained a foothold, when the patient begins to display
symptoms. Physicians are consequently forced to play catch-up. As is true
in cancer, treatments are generally much more effective in the early stages
of a disease, before the pathology—the disease—has had time to progress
and spread. Better yet, preventing the disease from ever getting started
avoids the expense of a treatment, as well as any side effects it may cause.
Doctors cannot be on guard at every moment, but a nanobot might.
Imagine a squadron of tiny machines as they patrol the body. The nano-
bots swim through the bloodstream and the extracellular spaces, inspect-
ing cells and proteins in search of any signs of damage or pathological
situations or agents. When they spot their quarry, they automatically
attack, perhaps replicating themselves if reinforcements are needed.
As of now, building such nanobots is not within nanotechnology's
capacity. But there is no reason why these machines could not one day
be developed, as Richard Feynman pointed out in his 1959 lecture. The
mechanisms of diagnosing or detecting diseases on the molecular scale
is advancing rapidly, and researchers are finding ingenious ways of
miniature propulsion. Certain bacteria, for instance, propel themselves
through water by swinging a whip, known as a flagellum, which has