Dual-labeled time-resolved immunofluorometric assay for the determination of IgM antibodies to rubella virus and cytomegalovirus in human serum.

Abstract Objectives This study established a novel time-resolved fluorescence immunoassay (TRFIA) that allows the simultaneous determination of rubella virus (RV) IgM and cytomegalovirus (CMV) IgM in human serum. Design and methods Lanthanum elements labeled antibody and streptavidin–biotin system were used in the “capture sandwich” format simultaneously. Results The working range of TRFIA for RV IgM was 2–80 AU/mL and for CMV IgM was 5–400 AU/mL. Intra- and inter-assay coefficient of variation (CV) for RV IgM and CMV IgM were both less than 10% and recoveries were from 90% to 110%. No significant statistical difference in sensitivity or specificity was observed between dual-TRFIA and commercial chemiluminescent immunoassays (CLIA) in serum samples. Conclusion The novel dual-TRFIA for RV IgM and CMV IgM detection might have valuable clinical application, with satisfactory sensitivity, specificity and accuracy.