Monitoring the LH Surge by Ultrarapid and Highly Sensitive Immunofluorometric Assay

A novel time-resolved immunofluorometric method is described for the estimation of human luteinizing hormone (LH) in serum and urine. The method utilizes two monoclonal antibodies: one reacting with the beta-subunit is adsorbed to the wall of a microtiter well, and the other is labeled with a fluorescent europium chelate and reacts with the alpha-subunit. The method is ultrarapid (15-30 min) and highly sensitive (1 IU/L). A large linear measuring range allows measurement of LH levels from 1 to 250 IU/L. For the monitoring of urinary LH, IFMA gives the same information as the Hi-Gonavis assay, but it has the advantages of greater sensitivity and a shorter assay time. For the determination of serum LH levels, an acceptable correlation was observed between radioimmunoassay and IFMA. Furthermore, IFMA has a greater sensitivity, and is more rapid and not dependent on the handling of radioactive materials.