NH3 Ammonia test
About the parameter
The bulk of ammonia in the body is generated in the gastrointestinal system by action of bacterial enzymes on the contents of the colon and from hydrolysis of glutamine. It is removed in the liver and converted to urea through a series of enzymatic reactions in the Krebs-Henseleit cycle. Among other conditions, advanced liver disease and hepatic encephalopathy result in elevated levels of ammonia in blood. Hyperammonemia is also common in inherited deficiencies of the enzymes involved in the conversion of ammonia to urea. The determination of ammonia is very useful in the diagnosis and prognosis of Reye’s Syndrome. Elevated blood ammonia exerts toxic effects on the central nervous system.
Ammonia reacts with alpha-ketoglutarate and reduced cofactor to form L-glutamate and the cofactor. The reaction is catalyzed by glutamate dehydrogenase.
The decrease in absorbance due to the oxidation of the reduced cofactor is monitored at 340 nm and is proportional to the ammonia concentration.
The accuracy of ammonia determination is extremely dependent on sample collection. Use only fresh EDTA plasma (ammonia heparin plasma or serum must not be used). After drawing the blood immediately centrifuge the collection tube to get plasma. The plasma sample has to be analysed within 5 minutes on the instrument.
Measurement range*: 10 – 1100 µmol/l
Lower detection limit*: 10 µmol/l
Test takes approx. 8.5 minutes.
More details can be found in the package insert.
Please note: All package inserts provided on this website are intended for information purposes only! Always process all tests, controls and calibrators strictly according to the package insert provided with the kit.
ST 0500 NH3 Ammonia test kit (containing 16 tests)
ST 5000 NH3 Ammonia control kit (1 x 5 ml – decision level)