Development and validation of a fluoroimmunoassay for urinary normetanephrine.
The development of a separation fluoroimmunoassay for urinary normetanephrine is described. Antiserum specific to normetanephrine was coupled, using cyanogen bromide, to magnetizable cellulose; and fluorescein labelled normetanephrine was synthesized from fluoresceinthiocarbamylethylene diamine and a previously described normetanephrine derivative. Using these reagents it was possible to construct a reproducible standard curve, covering a wide range of concentrations, and to accurately measure the concentration of this metabolite in acid-hydrolysed urine samples. Cross-reactivities of structurally similar compounds were low and the fluoroimmunoassay showed good correlation with an established gas-chromatographic assay. The procedure is rapid; it is possible to accurately determine the normetanephrine concentration of urine samples approximately 2 h after hydrolysis, resulting in an overall assay time of approximately 4 h. This is the first report of a non-isotopic immunoassay for normetanephrine.
Gallacher
G
G
Department of Biochemistry, Basic Medical Sciences, Queen Mary and Westfield College, London, UK.
Mellor
G W
GW
Landon
J
J
Sjostrom
L
L
D000818:Animals; D003429:Cross Reactions; D019793:Fluorescein; D005452:Fluoresceins; D015200:Fluoroimmunoassay / Q000379:methods*; D006801:Humans; D007074:Immunoglobulin G; D009647:Normetanephrine / Q000652:urine*; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D012756:Sheep
D005452:Fluoresceins; D007074:Immunoglobulin G; D009647:Normetanephrine; D019793:Fluorescein