Technetium
The first element made rather than found, and now the one most often injected into human beings.
Technetium has no stable isotope. Every atom of it that ever existed on Earth has long since decayed, which is why the gap at atomic number 43 resisted filling for so long and why the element was eventually produced in a cyclotron rather than dug up.
Its practical importance is medical. One isotope, technetium-99m, emits a gamma ray energetic enough to leave the body and be imaged, and decays fast enough that a patient is not left carrying it. That combination is unusual, and it made technetium the workhorse of diagnostic nuclear medicine.
Name origin
From the Greek tekhnetos, artificial — the first element whose name records that it was manufactured rather than discovered in the ground.
Uses
Technetium-99m dominates. It is bound to a carrier molecule chosen for where it should collect — bone, heart muscle, thyroid — injected, and the gamma emission mapped to show how that tissue is behaving rather than merely how it is shaped.
The isotope is short-lived enough that hospitals cannot stockpile it. Instead they hold a generator containing its longer-lived parent and draw off fresh technetium as it forms, which is a supply arrangement unlike almost anything else in medicine.
How we know: checked recently · only one source, so there is nothing to cross-check it against · stated directly by the source.
How this connects
Where a connection has been confirmed by an outside reference, that reference is named beside it.
is used as
- Medical imaging — application
is produced by
- Neutron irradiation — process · not by capture but as a fission product — a fragment of a split uranium nucleus, recovered from spent fuel in quantities no deliberate synthesis would match
Sources
- Material WorldOur own writing
- Wikimedia Foundation · Creative Commons CC0 1.0 Universal (public domain dedication)
- US National Library of Medicine · Mixed — aggregated third-party content, rights retained by depositors