Technetium (
99mTc) medronic acid is a
pharmaceutical
A medication (also called medicament, medicine, pharmaceutical drug, medicinal drug or simply drug) is a drug used to diagnose, cure, treat, or prevent disease. Drug therapy (pharmacotherapy) is an important part of the medical field and re ...
product used in
nuclear medicine
Nuclear medicine or nucleology is a medical specialty involving the application of radioactive substances in the diagnosis and treatment of disease. Nuclear imaging, in a sense, is "radiology done inside out" because it records radiation emitting ...
to localize bone
metastases
Metastasis is a pathogenic agent's spread from an initial or primary site to a different or secondary site within the host's body; the term is typically used when referring to metastasis by a cancerous tumor. The newly pathological sites, then, ...
as well as other diseases that can alter the natural turn-over in the
bone
A bone is a Stiffness, rigid Organ (biology), organ that constitutes part of the skeleton in most vertebrate animals. Bones protect the various other organs of the body, produce red blood cell, red and white blood cells, store minerals, provid ...
by
bone scintigraphy
A bone scan or bone scintigraphy is a nuclear medicine imaging technique of the bone. It can help diagnose a number of bone conditions, including cancer of the bone or metastasis, location of bone inflammation and fractures (that may not be visi ...
.
[FDA Label: MDP Multidose Utilipack](_blank)
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Chemistry
The drug is a complex
Complex commonly refers to:
* Complexity, the behaviour of a system whose components interact in multiple ways so possible interactions are difficult to describe
** Complex system, a system composed of many components which may interact with each ...
of medronic acid
Medronic acid (conjugate base, medronate), also known as methylene diphosphonate, is the smallest bisphosphonate. Its complex with radioactive technetium, 99mTc medronic acid, is used in nuclear medicine to detect bone abnormalities, including m ...
(MDP, methylene diphosphonate), the simplest bisphosphonate
Bisphosphonates are a class of drugs that prevent the loss of bone density, used to treat osteoporosis and similar diseases. They are the most commonly prescribed drugs used to treat osteoporosis. They are called bisphosphonates because they ...
, with technetium-99m
Technetium-99m (99mTc) is a metastable nuclear isomer of technetium-99 (itself an isotope of technetium), symbolized as 99mTc, that is used in tens of millions of medical diagnostic procedures annually, making it the most commonly used medical ra ...
(99mTc), a radionuclide
A radionuclide (radioactive nuclide, radioisotope or radioactive isotope) is a nuclide that has excess nuclear energy, making it unstable. This excess energy can be used in one of three ways: emitted from the nucleus as gamma radiation; transfer ...
that emits gamma rays
A gamma ray, also known as gamma radiation (symbol γ or \gamma), is a penetrating form of electromagnetic radiation arising from the radioactive decay of atomic nuclei. It consists of the shortest wavelength electromagnetic waves, typically ...
. The exact structure of the complex is not known.
Manufacture
99mTc-MDP must be prepared in a radiopharmacy
Nuclear pharmacy, also known as radiopharmacy, involves preparation of radioactive materials for patient administration that will be used to diagnose and treat specific diseases in nuclear medicine. It generally involves the practice of combining ...
. It is usually supplied as a "cold kit" to which radioactive 99mTc from a generator
Generator may refer to:
* Signal generator, electronic devices that generate repeating or non-repeating electronic signals
* Electric generator, a device that converts mechanical energy to electrical energy.
* Generator (circuit theory), an eleme ...
is added. Kit composition may vary between suppliers, but contents typically includes medronic acid, stannous chloride dihydrate and sometimes ascorbic acid
Vitamin C (also known as ascorbic acid and ascorbate) is a water-soluble vitamin found in citrus and other fruits and vegetables, also sold as a dietary supplement and as a topical 'serum' ingredient to treat melasma (dark pigment spots) an ...
. Pertechnetate
The pertechnetate ion () is an oxyanion with the chemical formula . It is often used as a convenient water-soluble source of isotopes of the radioactive element technetium (Tc). In particular it is used to carry the 99mTc isotope (half-life 6 hou ...
, eluted
In analytical and organic chemistry, elution is the process of extracting one material from another by washing with a solvent; as in washing of loaded ion-exchange resins to remove captured ions.
In a liquid chromatography experiment, for exa ...
from the generator is added to the kit vial, which is swirled and left to stand. The labelling efficiency, an indication of how much 99mTc remains in pertechnetate form rather than bound to the MDP, can be measured using chromatography
In chemical analysis, chromatography is a laboratory technique for the separation of a mixture into its components. The mixture is dissolved in a fluid solvent (gas or liquid) called the ''mobile phase'', which carries it through a system (a ...
.
References
External links
*
Bisphosphonates
Technetium-99m
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