Why can't the manufacturers keep a decent inventory of these products on hand so there isn't a shortage every time they have a scheduled reactor shutdown?
2007-12-04 09:23:32 · 2 answers · asked by michinoku2001 7 in Science & Mathematics ➔ Physics
The most important reason is that radioisotopes are mutagens.
The must have a short half life or they would be useless to medicine. If they had a long half-life they would cause ireprable damage besides what they are ueful for .
In cancer you use a short lived radioisotope to cause massive mutation in fast growing cells. These include cancer cells bone marrow cells and the cells of the alimentary canal.
They use the longest half-life they can use withough killing the patient outright. The patient is still debilitated severely.
In general it is a fine line between haveing a half-life long enough to effect cancercells but still short enough to not destroy the patients altogether.
2007-12-04 09:35:38 · answer #1 · answered by Asclepius 3 · 1⤊ 0⤋
Yeah, as the first author mentioned Tc-99m is probably the most commonly used radiotag used in Nuclear Med because it's got a half-life of six hours and can be tagged to a lot of agents. I-131 is used for treatment. We can tag a whole bunch of chemicals with radioisotopes for imaging (hence radiopharmaceuticals) depending on the matter we wish to study. Radioisotopes decay by different mechanisms and we need different energy/type/collamated cameras to pick it up. With PET becoming big in terms of diagnosis/treatment followup, agents that decay by positron emission (as opposed to gamma emission) certainly will become more prevalent in clinical practice, e.g. FDG-18 radiolabeling (especially as fusion CT/PET becomes more mainstream).
2016-05-28 04:46:36 · answer #2 · answered by Anonymous · 0⤊ 0⤋