General Estrone Sulfate (E1S) ELISA Kit

A competitive inhibition immunoassay from Assay Genie quantifies estrone sulfate (E1S), the conjugated estrogen form that dominates the postmenopausal circulating pool. The kit ships configured for 96 assays on a pre-coated microplate and pairs with a standard absorbance reader for endpoint quantitation. Sensitivity has been validated at 0.51 ng/mL, with a working detection range of 1.56 to 100 ng/mL against a 100 ng/mL top standard. The two-hour protocol uses a 50 µL sample input per well and relies on biotinylated antibody plus streptavidin-HRP detection chemistry terminated with an acidic stop solution. Cross-reactivity testing against E1S analogs showed no significant interference, supporting specificity for the sulfated estrone target. Shelf life is 12 months when stored at the recommended refrigerated temperatures (4 °C for short-term use, –20 °C for longer preservation). Inputs derive from serum or plasma-type liquid biospecimens after standard centrifugation, with aliquots held at –80 °C to limit freeze-thaw drift. For research use only.