Particle counting immunoassay of choriogonadotropin using monoclonal antibodies

A latex particle immunoassay has been developed for the quantification of choriogonadotropin in human serum using two monoclonal antibodies specific for the beta-chain of the hormone. The assay, based on optical counting of monomeric particles, was achieved in 40 min and the calibration curve was linear between 10 and 200 IU/l. Intra- and interassay precisions at three different levels of the curve varied between 3.3 and 10.9%. The method was validated by comparison with two different radioimmunoassays and correlation coefficients of 0.97-0.99 were obtained.