Technicium-99m

What is Technicium-99m

Technicium-99m is a man made element designed for radioactive screening of the human body. The half-life of Technicium-99m is around 6 hours. This is to minimise the exposure of radiation to the human body and reduce impact it has on living cells. However this also implicates that the facility producing Technicum-99m must be nearby or that it is quickly transported to the hospital.

How is Technicium-99m produced?

Technicium-99m is produced by neutron absorption of Molybdenum-98. Molybdenum-99 then slowly decays to form Tc-99m, m stands for a meta-stable state of Tc-99. Chemically, Tc-99m is a reactive chemical and has multiple oxidation states; this property is beneficial as it allows Technicium to chemically bond to organic chemicals and be deposited to a variety of compounds. Combined with a tin compound it can then bind to red blood cells, allowing the circulatory system to be mapped and bleeding/clot sites to be detected. When combined with a pyrophosphate ion Tc-99m sticks to calcium deposits in damaged heart tissue, allowing for myocardial perfusion imagery. Sulfur colloid can also be combined with Tc-99m to be taken by the liver or spleen, making imaging of these organs easier. Tc-99m emits low energy gamma radiation even at low energy gamma radiation, minimising the damage to healthy tissue and the high penetrative ability of gamma radiation allows it to penetrate bodily tissues and allow it to be detected outside the body.Tc-99m has a half life of 6hrs, this is also beneficial as there is minimal exposure to radiation to the patient. However, such a short life span had disadvantages.
As with any radioisotopes with a short life span the source must be situated close to the hospital or produced on site with a cyclotron. Exposure to radiation can cause tissue damage and over long term exposure can cause cancer. Gamma radiation can cause genetic mutation, enzyme denaturing and disruption to protein synthesis. Tc-99m exposure is kept to a minimum when not in use by storing in a lead case. Although care must be taken in its use, Tc-99m has greatly enhanced diagnostic techniques in medicine.