A protein-binding assay for measurement of biotin in physiological fluids.
A sensitive and convenient protein-binding assay for biotin in physiological fluids is described. The method is based upon the binding of an iodinated biotin conjugate by avidin followed by separation of bound and free conjugate by charcoal absorption. Adult plasma biotin levels averaged 1.26 pmol/ml, a value comparable to that determined by microbiological assays for biotin.