Estrone (E1), ELISA, 96-test

The Estrone (E1), ELISA is an immunoassay for the quantitative and sensitive detection of Estrone. Kit Principle: Competitive Reaction The test is based on the recognition of E1 by specific monoclonal antibodies. E1 present in the sample and an E1-enzyme conjugate (i.e. E1 labeled with a coloring enzyme) are premixed and added into each well of a microplate, and allowed to compete for limited number of binding sites of specific antibodies immobilized on the surface of the wells. When the E1 concentration is higher relative to the enzyme conjugate, the E1 will predominantly bind the antibody and vice versa. Chromogenic Reaction Unbound E1 and excess E1-enzyme conjugates are washed out. The presence of E1 is detected by adding a chromogenic substrate:TMB. The enzyme-labeled E1 bound to the E1 antibody in the plate, catalyzes the conversion of the substrate to a colored product. After an incubation period, the reaction is stopped by the addition of a diluted acid. The higher the E1 concentration in a sample, for example, leads to less antigen-enzyme conjugate bound to the antibody binding sites in a microplate well, generating a lighter color, i.e. lower absorbance. Quantitative Analysis The standard curve, a dose-response curve obtained from known concentrations of E1 standards, is determined from the absorbance at 450nm. The E1 concentration in each sample is accurately calculated by interpolation using the absorbance intensity obtained from the standard curve. Features -Estrone(E1) monoclonal antibody binds exclusively with E1 and does not show cross-reaction with other chemicals of similar structures. A monoclonal antibody is uniform in quality, generating very little lot-to-lot variation. -The quantitative analysis ranges from 0.05μg/L to 5μg/L (ppb). -The ELISA measurement is highly reproducible; the coefficient of variation (CV) is mostly under 10%. -The assay requires less amount of harmful solvent than instrument analyses. -With ease of handling, the total time for measurement is only 2.5 hours. -The kit, a 96-well microplate format, enables simultaneous measurement of multiple samples at more reasonable cost.