Bioanalysis of digoxin and its metabolites using direct serum injection combined with liquid chromatography and on-line immunochemical detection.
An automated dual-column liquid chromatographic assay for digoxin is described. Serum samples are directly injected onto a restricted-access solid-phase extraction support. After liquid chromatographic (LC) separation on a C18 analytical column, antigenic analytes are detected by means of post-column immunochemical detection (ICD) using fluorescein-labelled antibodies against digoxigenin. The detection limit of this assay is 160 pg/ml (preconcentration of 1.0 ml serum). With the present method digoxin and three of its cross-reactive metabolites were determined in serum taken from patients which were orally administered a 1-mg dose of digoxin. The results obtained with LC-ICD were compared with data provided by a batch immunoassay.
Leiden/Amsterdam Center for Drug Research, University of Leiden, Netherlands.
A J
AJ
Oosterkamp
H
H
Irth
M
M
Beth
K K
KK
Unger
U R
UR
Tjaden
J
J
van de Greef
D015415:Biomarkers; D002851:Chromatography, High Pressure Liquid; D003429:Cross Reactions; D004076:Digoxigenin / Q000276:immunology; D004077:Digoxin / Q000032:analysis* / Q000097:blood / Q000276:immunology; D015200:Fluoroimmunoassay; D006801:Humans; D007120:Immunochemistry
D015415:Biomarkers; D004077:Digoxin; D004076:Digoxigenin