T. Nurmi et H. Adlercreutz, Sensitive high-performance liquid chromatographic method for profiling phytoestrogens using coulometric electrode array detection: Application to plasma analysis, ANALYT BIOC, 274(1), 1999, pp. 110-117
An HPLC method for profiling 13 phytoestrogens and their metabolites using
coulometric electrode array detection was developed, Sensitivity of the met
hod was slightly less than that of-our GC-MS method, but significantly high
er compared to the HPLC methods using diode-array or UV detection. Detectio
n limits varied from 3.4 (secoisolariciresinol) to 40.3 (genistin) pg on co
lumn. Signal linearities ranged from the detection limits to 61 ng on colum
n. Resolution values for the peak pairs varied from 1.1 (O-desmethylangolen
sin-anhydrosecoisolariciresinol) to 16 (daidzin-genistin). Intra- and inter
assay retention time variations were negligible and detector response varia
tion was eliminated by frequent calibration. Chromatographic method was app
lied to plasma analyses and 6 of the 13 compounds were detected. Method acc
uracy for those six analytes varied from 69% (enterodiol) to 118% (genistei
n), Intraassay precision CVs ranged from 1.5% (enterolactone, 12.4 nmol/lit
er) to 14% (genistein, 245 nmol/liter) and interassay precision CVs ranged
from 9.9% (daidzein, 67.4 nmol/liter) to 44% (enterodiol, 1.20 nmol/liter).
(C) 1999 Academic Press.