title: Europium and samarium as labels in time-resolved immunofluorometric assay of follitropin.
abstract: This time-resolved immunofluorometric assay for human follitropin involves use of europium- or samarium-labeled monoclonal antibodies, with an average incorporation ratio of 3 mol of Eu3+ or Sm3+ per mole of antibody. These lanthanide ions are bound to the antibody molecules by means of the anhydride of diethylenetriaminepentaacetic acid. The solid-phase antibody is immobilized inside polystyrene tubes in which plasma samples were assayed in a one-step procedure. After incubation, the fluorescence intensity of Eu3+ or Sm3+ label is measured by time-resolved fluorometry, with a nitrogen laser as the pulsed excitation source. The sensitivity of the assay is largely better with Eu3+ than with Sm3+ because of the difference in their intrinsic luminescence properties. Results obtained with the proposed methods correlated well with those by an immunoradiometric method.
mesh_terms: D000293:Adolescent; D000328:Adult; D000911:Antibodies, Monoclonal; D005063:Europium; D005260:Female; D005470:Fluorometry / Q000295:instrumentation; D005640:Follicle Stimulating Hormone / Q000097:blood* / Q000592:standards; D006801:Humans; D007118:Immunoassay / Q000379:methods; D007202:Indicators and Reagents; D008163:Luminescent Measurements; D008297:Male; D008875:Middle Aged; D012493:Samarium
chemical_list: D000911:Antibodies, Monoclonal; D007202:Indicators and Reagents; D012493:Samarium; D005063:Europium; D005640:Follicle Stimulating Hormone