Ammonia Enzymatic Assay plasma 25-1700µg/dL Single liquid reagent system UV GLDH method Sentinel Diagnostics

Ammonia Enzymatic manufactured by Sentinel Diagnostics


Catabolism of dietary protein by intestinal bacteria produces ammonia which is then detoxified in the liver. The toxic ammonia is converted to urea in the hepatocytes. Excess ammonia can have a toxic effect on the central nervous system and result in neurological disturbances. Elevated ammonia may be in observed in individuals with severe liver failure such as patients with Reye's syndrome, viral hepatitis or liver cirrhosis.

The Sentinel Diagnostics Ammonia Ultra kit uses an enzymatic method to determine the concentration of ammonia in plasma (EDTA or heparin but not ammonium heparin). In the presence of glutamate dehydrogenase (GLDH) ammonia combines with alpha-ketoglutarate and NADH to yield glutamate and NAD+. As NADH is converted into NAD+ there is a decrease in absorbance at 340nm, the change is absorbance measured is proportional to the ammonia concentration in the sample. The Ammonia Ultra reagent also contains lactate dehydrogenase (LDH) in excess which rapidly reduces any endogenous pyruvate so that this does not interfere with the assay system. An ammonia standard is also included in the Ammonia Ultra kit.

The assay has a measurable range of 25-17 µg/dL. The Ammonia Ultra reagent has an open vial stability (OVS) of 90 days and the ammonia standard OVS is 120 days provided that both are stored at 2-8C. The recommended controls for this assay are 16635 Ammonia Controls which offer 3 levels of analyte in a protein matrix.