A radioimmunoassay of bile acids.

A radioimmunoassay for beta-muricholic acid was developed using an antiserum which was prepared by injecting beta-muricholic acid conjugated with bovine serum albumin into rabbits. The antiserum reacted with glyco-beta-muricholic, tauro-beta-muricholic and beta-muricholic acids, but not with other bile acids. The radioimmunoassay showed good reproducibility with inter- and intra-assay coefficients of variations of 6% to 15%. When the validity of the method was examined by comparing it with a gas-liquid chromatography method, a linear correlation was obtained.