Time-resolved fluoroimmunoassay of plasma and urine O-desmethylangolensin

摘要: Abstract We present a method for the determination of phytoestrogen metabolite O -desmethylangolensin ( -DMA) in plasma (serum) and urine. -DMA is daidzein, which occurs soybeans. It has been suggested that isoflavones may afford protection against breast prostate cancer therefore, also metabolites are interest. The based on time-resolved fluoroimmunoassay (TR–FIA) using europium chelate as label. After synthesis 4′′- -carboxymethyl- -DMA, this compound coupled to bovine serum albumin, then used antigen immunization rabbits. tracers with synthesized same -derivative α-methyldeoxybenzoin. enzymatic hydrolysis ether extraction immunoassay carried out by time resolved (TR–FIA). Cross-reactivity was tested angolensin, dihydrogenistein, dihydrodaidzein, equol, 6′-OH-angolensin, trans -4-OH-equol, 6′-OH- cis -4-OH-equol 5-OH-equol. antiserum cross-reacted only angolensin. This cross-reactivity seems not influence results, were highly specific. Plasma samples hydrolyzed extracted. Urine analyzed directly after without extraction. correlation coefficient between TR–FIA results GC–MS high; r value 0.985. urine high over entire range concentrations (0–1500 nmol/l); 0.976, but lower low concentration (0–100 nmol/l), i.e. 0.631. intra-assay coefficients variation (CVs) at three different varied 2.8–7.7 3.0–6.0%, respectively inter-assay CVs 3.8–8.9 4.4–6.6%, respectively. working assays 0.5–512 nmol/l.