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# How does molybdenum 99 decay to technetium-99?

## How does molybdenum 99 decay to technetium-99?

Technetium was created by bombarding molybdenum atoms with deuterons that had been accelerated by a device called a cyclotron. Molybdenum-98 becomes molybdenum-99 when it captures a neutron. Molybdenum-99, with a half-life of 65.94 hours, decays into technetium -99 through beta decay.

What is the decay constant of technetium-99?

For 99Tc, T = 211,000 years = 6,658,653,600,000 seconds. A = (0.693 × 1,000,000)/6,658,653,600,000 = 0.000000104 decays per second = 3.3 decays per year.

What is the decay equation for technetium-99m?

Example: Tc-99m has λ= 0.1151 hr-1, i.e., 11.5% decay/hr Mo-99 has λ = 0.252 day-1, i.e., 25.2% decay/day • If nuclide has several decay modes, each has its own λi.

### What are the products of technetium-99 decay?

Technetium-99 (99Tc) is an isotope of technetium which decays with a half-life of 211,000 years to stable ruthenium-99, emitting beta particles, but no gamma rays.

What is Moly 99 used for?

The decay product of Mo-99, Tc-99m, is the workhorse isotope in nuclear medicine for diagnostic imaging. Tc-99m is used for the detection of disease and for the study of organ structure and function.

Why is technetium-99 a good tracer?

Tc-99 m is ideal as a medical tracer because the gamma radiation it emits allows the medical practitioner to image internal body organs causing hardly any radiation damage to the patient. Approximately 85% of diagnostic imaging procedures in nuclear medicine use this isotope.

#### Does the human body use technetium?

Technetium and Health Technetium-99 can pose a health risk when it enters the body. Once in the human body, Tc-99 concentrates in the thyroid gland and the gastrointestinal tract. The Tc-99m used in medical diagnostics has a short, six-hour half-life and does not remain in the body.

Why is TC 99 used in medical diagnostics?

Tc-99m is the preferred tracer for a number of scans used in medicine worldwide to help diagnose medical conditions. Tc-99m scans are used to detect a wide range of conditions including injuries, infections, tumours, heart disease, thyroid abnormalities, kidney conditions and also to guide some cancer procedures. heart.

What does the M in technetium 99m stand for?

metastable
Technetium-99m is a metastable nuclear isomer, as indicated by the “m” after its mass number 99. This means it is a decay product whose nucleus remains in an excited state that lasts much longer than is typical.

## Why is molybdenum-99 important nuclear medicine?

The decay product of Mo-99, Tc-99m, is the workhorse isotope in nuclear medicine for diagnostic imaging. Tc-99m is used for the detection of disease and for the study of organ structure and function. This irradiation causes U-235 to fission and produces Mo-99 and many other fission products, including I-131 and Xe-133.

Where does technetium go in the body?

Technetium and Health Once in the human body, Tc-99 concentrates in the thyroid gland and the gastrointestinal tract. However, the body constantly gets rid of Tc-99 in feces.

How is the molybdenum-technetium generator based on the principle?

The molybdenum-technetium generator system is based on the principle that the shorter-lived radioactive daughter nuclide ( 99m Tc) can be easily and repeatedly isolated from its longer-lived parent radionuclide ( 99 Mo). This is possible because of the physical differences resulting from the chemistry of these two elements.

### How is molybdenum-99 removed from a generator?

The Mo-99 in the generators decays with about a 66-hour half-life to Tc-99m. The Tc-99m is typically recovered by passing a saline solution through the alumina column in the generator, a process known aselutingthe generator. The saline removes the Tc-99m but leaves the Mo-99 in place.

How are molybdenum-99 and Tc-99m used in medicine?

FIGURE 2.2 Plot of typical Mo-99 and Tc-99m activity on a logarithmic scale versus time for multiple elution of a technetium generator. There are numerous Tc-99mkits5for producing radiopharmaceuticals to examine the brain, kidney, heart, bone, liver, and lung.

Which is the chemical form of molybdenum 99?

This can be attributed to its ideal physical properties, such as its half-life, that allow for prolonged in vivo imaging and γ-photon single-energy emission at 140 keV, which is beneficial for effective imaging. The chemical form of 99m Tc occurs as 99m Tc-pertechnetate Tc 99 m O 4 −.