Dear all,

I am measuring the levels of estradiol in plasma in intact B6 females around 18 weeks old, using QuickStep Mouse Estradiol ELISA competitive assay (QSES033). I am getting for all mice values ranging from 100 to 600pg/mL of estradiol in plasma. However, looking at the literature, estradiol levels in plasma never exceeds 60pg/mL. The standard curves look fine and I cannot spot any mistake I could make during the procedure so I think the values I am getting are trustworthy. I performed also vaginal smears on the same animals and they seem to cycle normally, so I can detect histologically that they go through all the expected phases. So nothing apparently weird is happening with the physiology of the animals I am using. Can anyone provide some information/experimental experience on this matter? How is possible I am getting values 1 order of magnitude higher? Much appreciate.