Competitive ELISA

Competitive ELISA (Enzyme-Linked Immunosorbent Assay) is a lab technique used to measure specific substances, like hormones or drugs, in a sample. It works by mixing a known amount of labeled target molecule with the sample; both compete to bind to a limited number of specific antibodies. The more target substance in the sample, the less labeled molecule binds. After washing away unbound components, a color change indicates how much labeled molecule remained attached. The intensity of the color inversely correlates with the amount of target substance in the sample, allowing precise quantification.