Urea-14C
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Urea-14C
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CAS No:
594-05-8
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Formula:
CH4N2O
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Chemical Name:
Urea-14C
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Synonyms:
Urea-14C;[14C]Urea
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CAS No:
Description
UREA C 14 is a member of ureas.|Urea 14C is a urea molecule radiolabelled with a radioactive carbon-14. It is currently used for the Urea Breath Test (UBT) and is available as a rapid diagnostic test (marketed as PyTest) for the detection of Helicobacter pylori infections. H pylori is a common stomach bacteria that has been linked to a variety of upper gastrointestinal disorders such as gastritis, gastric and peptic ulcers, stomach cancer, and gastric mucosa-associated lymphoid-tissue (MALT) lymphoma. The UBT is indicated to confirm H. pylori infection and to monitor post-treatment for its eradication. Radiolabelled urea is available in two forms as 13C and 14C. Both forms can be used within the Urea Breath Test, however some may prefer 13C as it is non-radioactive compared to 14C, which may be preferable in pregnant women and children. The Urea Breath Test is based on the ability of the H. pylori enzyme urease to cleave urea into ammonia and carbon dioxide. As the urease enzyme is not present in mammalian cells, the presence of urease (and the products of urea cleavage) in the stomach is evidence that H. pylori bacteria are present. To detect H. pylori, urea labeled with 14C is swallowed by the patient. If gastric urease from H. pylori is present, urea is split to form CO2 and NH3 at the interface between the gastric epithelium and lumen and 14CO2 is absorbed into the blood and exhaled in the breath. Exhaled breath samples can then be collected and measured for the presence of radioactivity.|Urea C-14 is a radiolabelled urea molecule used to diagnose stomach ulcers caused by Heliobacter pylori. In the presence of H. pylori, urea C-14 is metabolized by urease to produce ammonia and radioactive carbon dioxide at the interface between the gastric epithelium and lumen. The radioactive carbon dioxide is absorbed in the blood and is detected when exhaled in the breath.
Drug Information
14C-urea is intended for use in the detection of gastric urease as an aid in the diagnosis of Helicobacter pylori (H. pylori) infection in the human stomach. The test utilizes a liquid scintillation counter for the measurement of 14CO2 in breath samples.|FDA Label
14C-urea that is not hydrolyzed by H. pylori is excreted in the urine with a half-life of approximately 12 hours. About 10% of the 14C remains in the body at 72 hours and is gradually excreted with a biological half-life of 40 days.
The urease enzyme is not present in mammalian cells, so the presence of urease in the stomach is evidence that bacteria are present. The presence of urease is not specific for H. pylori, but other bacteria are not usually found in the stomach. To detect H. pylori, urea labeled with 14C is swallowed by the patient. If gastric urease from H. pylori is present, urea is split to form CO2 and NH3 at the interface between the gastric epithelium and lumen and 14CO2 is absorbed into the blood and exhaled in the breath. Following ingestion of the capsule by a patient with H. pylori, 14CO2 excretion in the breath peaks between 10 and 15 minutes and declines thereafter with a biological half-life of about 15 minutes. Therefore, the detection of isotope-labelled carbon dioxide in exhaled breath indicates that urease is present in the stomach, and hence that H. pylori bacteria are present.
Urea-14C Use and Manufacturing
Human Drugs -> FDA Approved Drug Products with Therapeutic Equivalence Evaluations (Orange Book) -> Active Ingredients
Computed Properties
Molecular Weight:62.048
XLogP3:-1.4
Hydrogen Bond Donor Count:2
Hydrogen Bond Acceptor Count:1
Exact Mass:62.03560474
Monoisotopic Mass:62.03560474
Topological Polar Surface Area:69.1
Heavy Atom Count:4
Complexity:29
Isotope Atom Count:1
Covalently-Bonded Unit Count:1
Compound Is Canonicalized:Yes
Drug Function and Efficacy
No specific pharmacological effects are clearly mentioned from the above information