This colourless salt contains the pertechnetate anion, TcO−4 that has slightly distorted tetrahedron symmetry both at 296 K and at 100 K[2] while the coordination polyhedron of the sodium cation is different from typical for scheelite structure.

[5] In the absence of strong complexing ligands, TcO−4 is reduced to a +4 oxidation state via the formation of TcO2 hydrate.

[3] The half-life of 99mTc is long enough that labelling synthesis of the radiopharmaceutical and scintigraphic measurements can be performed without significant loss of radioactivity.

A majority of radiopharmaceuticals labelled with 99mTc are synthesized by the reduction of the pertechnetate ion in the presence of ligands chosen to confer organ specificity of the drug.

The resulting 99mTc compound is then injected into the body and a "gamma camera" is focused on sections or planes in order to image the spatial distribution of the 99mTc.

After a scanning is performed, it is recommended that a patient drink large amounts of water in order to expedite elimination of the radionuclide.