Simplified fluorometry of total metanephrines in urine
Christenson, R.H.; McGlothlin, C.D.; Hedrick, R.; Cate, J.C.
Clinical Chemistry 28(5): 1204-1207
1982
ISSN/ISBN: 0009-9147 PMID: 7074906 Document Number: 196011
A simplified fluorometric method for quantitatively determining metanephrines in urine is described. The method is based on the elution of metanephrines from an ion-exchange column followed by production of a fluorescent derivative that has excitation and emission maxima of 405 and 505 nm, respectively. Metanephrine concentrations as great as 7.0 mg/l were within the linear range of the assay. Analytical recovery of metanephrines was 82-87%. Cross contamination by catecholamines was insignificant. The upper range of normal was 520 .mu.g/24 h. Within-run and between-run CV were 5 and .apprx. 9%, respectively. Twenty-four-hour urine specimens from 5 patients with pheochromocytoma showed above-normal amounts of the metanephrines by this method.