Mouse Estrone Immunoassay kit is designed to quantitatively measure estrone present in extracted dried fecal samples, urine and tissue culture media samples. The kit is unique as it measures both non-conjugated estrone, estrone-3-sulfate and estrone 3-glucuronide in urine and fecal samples with almost equal affinity, allowing for non-invasive testing of this steroid. An estrone standard is provided to generate a standard curve for the assay. Standards or diluted samples are pipetted into a clear microtiter plate. An estrone-peroxidase conjugate is added to the standards and samples in the wells. The binding reaction is initiated by the addition of a polyclonal antibody to estrone to each well. After a 2 hour incubation the plate is washed and substrate is added. The substrate reacts with the bound estrone-peroxidase conjugate. After a short incubation, the reaction is stopped and the intensity of the generated color is read at 450nm.