so this is a competitive binding assay and we use the antibody, because it's extremely sensitive to the structure of the hormone, and secondly, we put on it either a radioimmune tag, so it's an, it's a radioactive tag and that would then be called a radioimmunoassayune or, or an ia or we add something that has a fluorescent tag on it and then those are called eli sa or these are fluorescent enzyme reactions.