Cortisol free in Saliva ELISA

Background:Cortisol (hydrocortisone) is the major glucocorticoid produced in the adrenal cortex. Cortisol is a potent stress hormone and the secretion is regulated by the Hypothalamic-Pituitary-Adrenal-axis (HPA-axis). The secretion of cortisol has a specific circadian rhythm with a curve presenting a sharp peak in the early morning and a gradually decrease over the day with a nadir in the evening. The position of this peak-value is strongly influenced by the average wake-up time during the past weeks. It is not dependent on the actual wake-up time of the specific day of sample collection (if different from the average wakeup time of the past week).

Description:
The Cortisol free in Saliva ELISA Kit is a solid phase enzyme-linked immunosorbent assay (ELISA), based on the principle of competitive binding. The microtiter wells are coated with a polyclonal rabbit antibody directed against the cortisol molecule. The samples are dispensed in the coated wells and incubated with the enzyme conjugate (cortisol conjugated to horseradish peroxidase). During incubation endogenous cortisol of a patient sample competes with the enzyme conjugate for binding to the coated antibody. The unbound conjugate is removed by washing the wells. Subsequently, the substrate solution is added and the color development is stopped after a defined time. The intensity of the color formed is inversely proportional to the concentration of cortisol in the sample. The optical density (OD) is measured at 450 nm with a microtiter plate reader. A calibrator curve is constructed by plotting OD values against concentrations of standards, and concentrations of unknown samples are determined using this standard curve.

Product features:
The kit contains reagents for 96 determinations;
Microtiter plate consisting of 12x8 (break-apart) strips;
Microtiter plate reader at 450 nm;
Analytical sensitivity: 0,019 ng/ml;
IVD