The detection of ovulation with a two-hour radioimmunoassay for human plasma luteinizing hormone using the centria analyzer.

We describe a rapid (2-h) radioimmunoassay for human plasma luteinizing hormone which utilizes the reagents from a commercially available kit. Standardization of the assay was achieved using plasma standards instead of a buffer system and the Centria radioimmunoassay centrifugal analyzer which allowed simultaneous initiation and termination of reactions in all assay tubes. The specifity, precision, and accuracy of the assay were equal to or better than the conventional 24-h assay. Since this assay is designed to derect the mid-cycle surge of luteinizing hormone, its decreased sensitivity was small price to pay for the speed with which a result could be obtained.