The Salbutamal (Sal) ELISA Test Kit is a competitive enzyme immunoassay for the quantitative analysis of clenbuterol in feed, tissue, and urine. The method of Salbutamal (Sal) ELISA Test Kit is based on a competitive colorimetric ELISA assay. The coupling antigen of Salbutamal has been coated in the plate wells. During the analysis, sample is added along with the primary antibody specific for the target antigen. If the target is present in the sample, it will compete for the antibody, thereby preventing the antibody from binding to the coated antigen attached to the well. Then add secondary antibody, tagged with a Horseradish Peroxidase enzyme, targets the primary antibody that is complexed to the drug coated on the plate wells. The resulting color intensity, after addition of substrates, has an inverse relationship with the Sal residues concentration in the sample.