Artificial Radioactivity Scope

Radioelements made available for all areas of the knowledge...

Des isotopes pour l'imagerie médicale
Des isotopes radioactifs artificiels à très court temps de vie sont maintenant fabriqués dans de grands hôpitaux, grâce à des cyclotrons. Incorporés comme marqueurs dans des molécules radiopharmaceutiques, ils sont utilisés dans des techniques d'imagerie médicale de pointe comme la tomographie par émission de positons.

The scope of the discovery of artificial radioactivity is fundamental. It shows that radioactivity is a main property of matter.

A new kind of radioactivity witnessed - the emission of positive electrons - shows that the proton and neutron play a symmetrical role in the nucleus. If a neutron becomes a proton, there is an emission of a negative electron and if it is the proton that becomes a neutron, a positive electron is emitted. This means that the fundamental strong and weak forces do not rely on the presence of an electrical charge in opposition to electromagnetic forces.

The ability given to man to create at will radioactive isotopes of all elements has found some uses in all fields of knowledge. Radioactive isotopes, having exactly the same chemical and physical properties as stable isotopes, it suffices to add a small amount of radioisotopes, that act as a tracer or marker, to allow one to follow the development of the chemical elements.

This tool has revolutionized biology. Until then, the analysis of organs and tissues was static; it is now possible to watch their biochemical change and measure the speed of the transformation of the living matter.

In biology, for example, the method of the indicators using synthetic radioactive elements will facilitate the study of problems of the localisation and of the elimination of various elements introduced in living organisms. In locations, that we shall learn about, where the radioactive elements will fix themselves, the radiation they emit will produce its effect on neighbouring cells. This will possibly find a use in medicine.

This prophetic declaration by Frédéric Joliot in 1935 reflects the intuition at the time of radio diagnostics, therapy and the functional exploration. Frédéric Joliot also devoted himself to biological studies using radioactive iodine.

If both medicine and biology have been revolutionized by the discovery of artificial radioactivity, other sectors would have also benefitted from it. We can see its uses in the different fields covered by this web site.

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