Enzyme-linked immunosorbent assay (ELISA) is a biochemical technique to detect the presence of an antibody or an antigen in a sample. Whereas an indirect ELISA is used to determine the amount of antibodies to a specific antigen in a sample, a Sandwich ELISA is used to determine the concentration of the analyte by use of antibodies that bind to the analyte (and a standard). A different way of determining the analyte concentration is a competetive ELISA, often called EIA - analogous to RIA. The latter technique is preferred for small analytes.
AAT Bioquest Alkaline Phosphatase Substrate Kits:
AAT Bioquest Horseradish Peroxidase (HRP) Substrate Kits: