Specific for human transferrin complex between transferrin and soluble transferrin receptor. Does not cross-react with mouse, rabbit, bovine transferrin and with human lactoferrin. Can be used for detection of transferrin in serum by sandwich immunoassay, for detection of transferrin - transferrin receptor complex by sandwich ELISA, recommended pairs for transferrin detection by sandwich immunoassay (coating - conjugate): 8B9 - 11D3.