Plasma Nor-/Metanephrines
Enzymeimmunoassay for the quantitative determination of unconjugated (free) Normetanephrine and Metanephrine in plasma
Normetanephrine and metanephrine are physiologically formed from the catecholamines noradrenaline and adrenaline by the enzyme catechol-Omethyltransferase (COMT). Increased levels of normetanephrine and metanephrine can be found in patients suffering from pheochromocytoma, ganglioneuroma and other neurogenic tumors.
The assay kit provides materials for the quantitative measurement of free normetanephrine and metanephrine in human EDTA plasma. Normetanephrine and metanephrine are separated from plasma proteins through addition of precipitation reagents and then are quantitatively acylated to their N-acylderivates.
The competitive Nor-/ Metanephrine ELISA kit uses the microtitre plate format. Metanephrine and normetanephrine, respectively, are bound to the solid phase of the microtiter plate. Acylated nor-/metanephrines from the sample and solid phase bound nor-/metanephrines compete for a fixed number of antiserum binding sites. When the system is in equilibrium, free antigen and free antigenantiserum complexes are removed by washing. The antibody bound to the solid phase nor-/metanephrines is detected by anti-rabbit IgG/peroxidase. The substrate TMB/peroxidase reaction is monitored at 450 nm. The amount of antibody bound to the solid phase nor-/metanephrines is inversely proportional to the nor-/metanephrines concentration of the sample.
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