Immunoradiometric assay for human serum amyloid P component

► Human serum amyloid P component (SAP) is of basic and clinical interest. ► We have validated a precise, sensitive immunoradiometric assay for human SAP. ► Free calcium must be absent to prevent interference by the SAP depleting drug, CPHPC. ► Results were similar by electroimmunoassay and a new commercial ELISA kit (Hycult).