RESUMO
Objective:To develop a luminescent oxygen channeling immunoassay for pregnancy associated plasm a protein A.Methods:The monoclonal antibody of PAPP-A was labeled with biotin ,the polyclonal antibody of PAPP-A was coated on receptor particles.The LOCI reagents also contained sensitizer particles coated with streptavidin.The optimal test conditions and analytical per-formance of the method were studied.Results:The within-run and the between-run coefficients of variation were 5.91%-7.94% and 6.14%-9.69%,respectively;the analytical sensitivity was 2.8 mU/L and the function sensitivity was 4.6 mU/L,good linear in 2.8 mU/L-8 000 mU/L range;the recovery rate was 96.7%-100.3%.The interference rate of hemolysis , icterus and triglycerides were less than 10%; there is no Hook effect of PAPP-A concentrations up to 8 000 mU/L;the correlation coefficient between clinical samples detection results and Time resolved fluoroimmunoassay analysis results was 0.974.Conclusion:This LOCI can be used for the quantitative of serum PAPP-A,and detection performance in line with the requirements of clinical diagnostic reagents .