Monday night – Technetium

I am radioactive !… 

At least for the next couple of hours .

 

I had a cardiac stress test today.. as I do about every 5 years.; it’s something my doc has me do bcause of the family history we have.. it’s  kinda  fun.. you get on a treadmill then they shoot you up with a radioactive gamma-emitting isotope (99Tc).. then they put you in a gamma CT scanner.. Every time it tells me I’m fine.. and today was the same.  

It does get me thinkign of the wierd life of Isotopes.. .. I read about 99Tc  . 

It  was discovered in 1938 by Emilio Segrè and Glenn T. Seaborg after bombarding natural molybdenum with 8 MeV deuterons in the 37-inch (940 mm) cyclotron of Ernest Orlando Lawrence‘s Radiation laboratory.[2]

I learned that the doeses.. which  are only useful fro about 6 hours are made locally by a company in Willisont using soemthing called a ‘Moly Cow” .. .. which Wikipedia helpfully explains thus:

Technetium-99m’s short half-life of 6 hours makes storage impossible and would make transport very expensive. It is instead its parent nuclide 99Mo that is supplied to hospitals after its extraction from the neutron-irradiated uranium targets and its purification in dedicated processing facilities.[notes 1][56] It is shipped by specialised radiopharmaceutical companies in the form of technetium-99m generators worldwide or directly distributed to the local market. The generators, colloquially known as a moly cows, are devices designed to provide radiation shielding for transport and to minimize the extraction work done at the medical facility. A typical dose rate at 1 metre from Tc-99m generator is 20-50 μSv/h during transport.[57] These generators’ output declines with time and must be replaced weekly, since the half-life of 99Mo is still only 66 hours.

Molybdenum-99 spontaneously decays to excited states of 99Tc through beta decay. Over 87% of the decays lead to the 142 keV excited state of Tc-99m. A
βelectronand a νeelectron antineutrino are emitted in the process (99Mo → 99mTc + β+ νe). The β
electrons are easily shielded for transport, and 99mTc generators are only minor radiation hazards, mostly due to secondary X-rays produced by the electrons (also known as Bremsstrahlung).

At the hospital, the 99mTc that forms through 99Mo decay is chemically extracted from the technetium-99m generator. Most commercial 99Mo/99mTc generators use column chromatography, in which 99Mo in the form of water-soluble molybdate, MoO42− is adsorbed onto acid alumina (Al2O3). When the 99Mo decays, it forms pertechnetate TcO4, which, because of its single charge, is less tightly bound to the alumina. Pulling normal saline solution through the column of immobilized 99MoO42−elutes the soluble 99mTcO4, resulting in a saline solution containing the 99mTc as the dissolved sodium salt of the pertechnetate. One technetium-99m generator, holding only a few micrograms of 99Mo, can potentially diagnose 10,000 patients[citation needed] because it will be producing 99mTc strongly for over a week.

Well.. that makes me feel better

The only let down.. is that I don’t appear to have gained any super powers

shucks

nite all, nite sam

-me

 

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