Free Estriol Saliva ELISA Assay Kit


The Eagle Biosciences Free Estriol Saliva ELISA Assay Kit is intended for the quantitative determination of Free Estriol in human saliva by an enzyme immunoassay. The Eagle Biosciences Free Estriol Saliva ELISA Assay Kit is for research use only and not to be used in diagnostic procedures.

Free Estriol Saliva ELISA Assay Kit

The Free Estriol Saliva ELISA Assay Kit is for Research Use Only

Size: 12 x 8 wells
Sensitivity: 0.058 ng/mL
Dynamic Range: 0.05–30 ng/mL
Incubation Time: 1 hour 20 minutes
Sample Type: Saliva, Serum
Sample Size: 20 µL
Controls Included

Assay Background for Free Estriol Saliva ELISA

The Free Estriol (also referred to as unconjugated estriol or uE3 in the literature) ELISA is a competitive immunoassay. Competition occurs between Estriol present in calibrators, controls, and samples and an enzyme-labeled antigen (conjugate) for a limiting number of anti-Estriol antibody binding sites on the microplate wells. After a washing step that removes unbound materials, the enzyme substrate is added, and approximately 15-20 minutes late the enzymatic reaction is terminated by addition of stopping solution .The resulting optical density (OD), measured with a microplate reader, is inversely proportional to the concentration of Estriol in the sample. A calibrator curve is plotted with a provided set of calibrators to calculate directly the concentration of estriol in samples and controls.
Serum and salivary assays follow the same procedure except that the volume of the calibrators, controls, and sample dispensed into the microplate wells in 10µL for serum assays and 20µLfor salivary assays.

Specimen Collection, Pretreatment, and Storage – Saliva

Avoid sample collection within 1 hour after eating a major meal or within 12 hours after consuming alcohol. Acidic or high sugar foods can compromise assay performance by lowering sample pH and influencing bacterial growth. To minimize these factors, rinse mouth thoroughly with water 10 minutes before the sample is collected. Do not use blood-contaminated specimens.

Specimen Collection
Approximately 0.1 mL of saliva is required per duplicate determination. Rinse mouth thoroughly with water 10 minutes before the sample is collected. Collect 1-2 mL of saliva into a clean proproylene tube without force or inducement.

Specimen Pre-Treatment
Following collection, the sample must be pretreated according to the following procedure:

  • Freeze the sample for a minimum of 2 hours.
  • Thaw the sample.
  • Vortex to mix and centrifuge the sample at 2000x g for 10 minutes.
  • Carefully remove the supernatant and transfer to a new labeled tube. The supernatant will be used in the assay procedure of the test.

Specimen Storage
Store pretreated saliva samples at 4C for up to 24 hours or freeze at or below -20C for up to 6 months. Samples that have been stored should be inspected to ensure they are free from precipitates before being used in the assay. If there are precipitates present, follow steps 3-4 in the specimen pretreatment section. Consider all human specimens as possible biohazardous materials

Related Products

Estriol Saliva LIA Kit
Total Estriol ELISA Assay Kit

Additional Information

Assay Background

Since the production of estriol in pregnant women depends on a healthy maternal-placental-fetal system, the estriol concentration is a marker of both placental and fetal normal development and metabolism; hence the determination of serum or saliva estriol concentration is instrumental for the assessment of fetus health in advanced pregnancy.

In non-pregnant women and men, estriol levels are low. Notwithstanding, one common application of salivary tests is the monitoring of the estriol levels in women undergoing hormone replacement therapy.

Due to significant temporal fluctuations in the concentrations of this hormone, multiple samples are recommended to obtain reliable results.

Standard Curve

Free Estriol Saliva ELISA Standard Curve


Product Manual

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