Automated specific fluorimetric methods for epinephrine and norepinephrine assay in a single biolgical extract

✍ Scribed by L. Peyrin; J.M. Cottet-Emard

• Publisher: Elsevier Science
• Year: 1973
• Tongue: English
• Weight: 823 KB
• Volume: 56
• Category: Article
• ISSN: 0003-2697
• DOI: 10.1016/0003-2697(73)90218-2

✦ Synopsis

Fluorimetric

differential assay of catecholamines yields correct values only if E/NE ratio is between l/5 to 1. In other cases, results are misleading, and an accurate estimation of each amine has to be done with specific methods based on a difference of oxidation pH or of stabilizing final mixture. We describe here a continuous-flow diagram allowing specific E estimation at pH 2.5: sensitivity is 1 rig/ml for E, and relative interference of NE is 3.4%. The selective estimation of NE can be done by continuous flow: oxidation is performed at pH 6.4, and a stabilizing mixture is added which inhibits completely E fluorescence. Sensitivity is 10 rig/ml for NE. For each of these procedures, we have studied optimal conditions (oxidation pH$ buffer nature and concentration, oxidant and stabilizing reagent nature, time for different steps).

Normal values of urinary excretion in 25 healthy subjects are: 90 k 21 pg/24 hr for NE and 20 k 4 @g/24 hr for E.