Metanephrine Plasma ELISA

>Background:Metanephrine and normetanephrine are the metabolites of the catecholamines epinephrine and norepinephrine, respectively . Cells derived from neuroendocrine tumors (e.g. pheochromocytoma and paraganglioma) are known to produce catecholamines, which are secreted episodically via vesicles into the blood stream. But beside this, a small portion of the catecholamines is metabolized inside the tumor cells to the corresponding catecholamines metabolites – namely metanephrine, normetanephrine (and 3-methoxytyramine in the case of dopamine) – which are secreted at low levels continuously into the blood stream. Recent studies and publications have shown that the quantification of these plasma free metanephrines and plasma free normetanephrines is the most accurate biochemical marker for the clinical diagnosis of pheochromocytoma and paraganglioma in patients. Pheochromocytoma and paraganglioma are rare neuroendocrine tumors and occur with an estimated annual incidence of 1 – 8 cases per 1,000,000. Therapeutic consequences should never be based on laboratory results alone, even if these results are assessed in accordance with the quality criteria of the method. Any laboratory result is only a part of the total clinical picture of the patient. Only in cases where the laboratory results are in an acceptable agreement with the overall clinical picture of the patient, it can be used for therapeutic consequences.

Description:
Enzyme Immunoassay for the quantitative determination of free metanephrine in plasma. The determination of metanephrine helps in the detection of paragangliomas and pheochromocytomas. Metanephrine (metadrenaline) is first extracted using an ion exchange matrix followed by an acylation process. The subsequent competitive ELISA uses the microtiter plate format. The antigen is bound to the solid phase of the microtiter plate. The acylated standards, controls and samples compete with the solid phase bound analytes for a fixed number of antibody binding sites. After the system is in equilibrium, free antigen and free antigen-antibody complexes are removed by washing. The antibody bound to the solid phase is detected by an anti-rabbit IgG-peroxidase conjugate using TMB as a substrate resulting in a colour reaction. The reaction is monitored at a wavelength of 450 nm. Quantification of unknown samples is achieved by comparing their absorbance with a reference curve prepared with known standard concentrations. Manual processing of the ELISA is recommended. The use of automatic laboratory equipment is the responsibility of the user. This in-vitro diagnostic is for professional use only.

Product features:
The kit contains reagents for 96 determinations;
Microtiter plate consisting of 12x8;
Microtiter plate reader at 450 nm;
Limit of detection: 14,9 pg/mL;
IVD.