Immunoassay of phytoestrogens in human plasma

Highly sensitive plasma immunoassay methods based on time-resolved fluorometry were developed for plasma enterolactone, genistein, and daidzein. For daidzein and genistein three types of methods and for enterolactone two different methods were developed and validated and the results compared with our gas chromatographic-mass spectrometric reference method. All three compounds may be determined in duplicate in a 2-300 mu plasma sample, even in subjects with low phytoestrogen values.