Establishment and Evaluation Time-resolved Fluoroimmunoassay for Carcinoembryenic Antigen

Objective To establish and evaluate the Time-resolved Fluoroimmunoassay(TrFIA)for serum carcinoembrynoic antigen(CEA). Methods We used solidphase sandwich TrFIA for quantification of CEA in human serum,including two anti-CEA monoclonal antibodys:one anti-CEA monoclonal antibody was coated on microplates and the other was labeled by Europium. The method was evaluated. Results The cross-reaction rate of the method in the cross reaction with AFP and CA19-9 was 0.25% and 3.5%,respectively,with no cross reaction with other cancer markes. The intra-assay qualitative cotrol variation coefficient of low,middle and high concentrations of CEA was 4.75%,4.25% and 2.89% ,respectively,and the inter-assay variation coefficient of low,middle and high concentrations of CEA was 9.55% ,7.38% and 3.69%,respectively. The mean recovery rate was 95.94%. The CEA-TrFIA Kit was very stable at 37℃ for seven days. Compared with the CEA-CLIA,the correlation coffecient of CEA-TrFIA was 0.9986. The low limit of detection(LLD),the biological limit of detection(BLD)and the function sensitivity (FS) of CEA-TrFIA Kit were 0.4315 ng/mL,1.000 ng/mL and 1.000ng/mL,respectively. The linear scope was 1.000-500.0ng/mL. Conclusion CEA-TrFIA is a new non-radioactive immunoassay,with high sensitivity,strong specificity,good precision, wide linear scope and long duration,which shows better clinical value.