Normetanephrine Plasma ELISA Kit (NMN)

INTENDED USE

Normetanephrine plasma ELISA kit is a method for measuring in vitro quantitative levels of free normetanephrine (NMN) in human plasma (EDTA, citrate) samples. This assay has a minimum detection limit of 23 pg/ml.

BACKGROUND

Normetanephrine is produced as a metabolite of the catecholamine norepinephrine though the action of catechol-O-methyl transferase on norepinephrine. A small portion of these catecholamines are metabolised inside cells into the corresponding catecholamines metabolites, all of these are then secreted at low levels continuously into the blood stream. Cells derived from neuroendocrine tumors (such as pheochromcytoma or paragangliomas) have been found to produce catecholamines in excess that can then be secreted episodically through vesicles into the blood stream.

The current publications and studies have demonstrated that analysing the plasma free-normetanephrine and plasma free-metanephrine is one of the most accurate biochemical marker that has been used to identify pheochromocytoma and in the subsequent follow-up of pheochromocytoma patients. The current guidelines are highly recommending the use of either plasma free-metanephrines or urinary fractionated metanephrines for the initial biochemical phase.

CONTENT

All reagents supplied need to be stored at 2 °C – 8 °C, unopened reagents will retain reactivity until expiration date. Do not use reagents beyond this date.

• Normetanephrine Microtiter Strips.
• Enzyme Conjugate.
• Substrate (TMB).
• Antiserum: Anti-normetanephrine rabbit antibody.
• Standards (A-F): Concentrations 0, 72, 240, 720, 2,400, 7,200 pg/ml
• Control 1 + Control 2.
• Wash Buffer Concentrate (50x).
• Stop Solution.
• Adjustment Buffer.
• Assay Buffer.
• Acylation Concentrate.
• Extraction Plate.
• Cleaning Concentrate (25x).
• Elution Buffer.
• Equalizing-Reagent: Human serum, negative for HIV I/II, HBsAg and HCV.
• Adhesive Foil.

SENSITIVITY

The minimum sensitivity level of free normetanephrine (NMN) in plasma using current normetanephrine plasma ELISA kit was approximately 23 pg/ml. The dynamic range for this assay is 48 – 4,800 pg/ml.

ASSAY CHARACTERISTICS

– Analytical Sensitivity: 17.9 pg/ml (LOD) and 22.8 pg/ml (LOQ)
– Analytical Sensitivity (Cross Reactivity): Derivatized Normetanephrine (100%), 3-Methoxytyramin (6.5%), Derivatized Metanephrine (0.72%).
– Intra Assay: 8.2 – 10.5%
– Inter Assay: 5.0 – 10.6%
– Recovery: 105 – 114%
– Linearity: 92 – 102%

REFERENCES

1. Plasma-free vs deconjugated-metanephrines for diagnosis of phaeochromocytoma. Clin Endocrinol (Oxf). (2013) 79 (4): 476-83. Pamporaki C., et al.
2. Seasonal variation in plasma free normetanephrine concentrations: implications for biochemical diagnosis of pheochromocytoma. Eur J Endocrinol. (2014) 170 (3): 349-57. Pamporaki C., et al.
3. A study of longer-time stability of plasma free-metanephrines. Ann Clin Biochem. (2011) 48 (Pt 3): 270-1. Ross H.A., et al.
4. Comparison of plasma metanephrines measured by a commercial immunoassay and urinary catecholamines in the diagnosis of pheochromocytoma. Scand J Clin Lab Invest. (2011) 71 (8): 695-700. Christensen T.T., et al.

ADDITIONAL INFORMATION

• Full Name: Normetanephrine Plasma ELISA Kit (NMN)
• Reactivity: Human
• Sample Type: Plasma (Citrate, EDTA)
• Sensitivity: 23 pg/ml

OTHER RELATED ELISA KITS

• Metanephrine Plasma ELISA Kit
• Nephrines Plasma (Metanephrine + Normetanephrine) ELISA Kit
• 3-CAT (Adrenaline/Noradrenaline/Dopamine) ELISA Kit