A sensitive enzyme immunoassay for the quantitation of human IgM

A highly sensitive and specific two-site solid-phase enzyme immunoassay for the quantitation of human immunoglobulin M (IgM) in biological fluids is presented. Detection limit is 20 micrograms/l (12 ng/tube). Routine working range is 30--1000 micrograms/l. Between-assay coefficient of variation is 10%. The assay allows quantitation of IgM in human cerebrospinal fluid.