Antibodies are employed in immunoassays, which are laboratory techniques used to detect and quantify substances. These assays exploit the specific binding affinity between an antibody and its corresponding antigen. Techniques such as Enzyme-Linked Immunosorbent Assay (ELISA), radioimmunoassay, and lateral flow assays are commonly used in toxicology for detecting a wide range of toxins, including drugs, pesticides, and heavy metals.