A Novel Time-Resolved Fluoroimmunoassay Using a Macrocyclic Europium Ligand as a Label

A novel macrocyclic ligand for Eu3+ (24, 30-diphenyl-1, 21 : 4, 6 : 10, 12 : 15, 17-tetraetheno-8, 9, 19, 20-tetrahydro-7H, 18H-dibenzo[b, k]-[1, 4, 7, 10, 13, 16]hexaazacyclooctadecine-8, 19-diacetic acid) was used to label an anti-human chorionic gonadotropin (hCG) monoclonal antibody. The time-resolved fluoroimmunoassay of hCG using this labeled antibody showed a linear response over the range 0.1 to 10 I.U. hCG/ml.