Comparative Study on Determination of Serum Carcino Embryonic Antigen by ICA and RIA and ELISA

Objective To assess the efficacy of magnetic particle capture immunochemical luminescent assay(ICA)for quantative determination of carcino embryonic antigen (CEA) in comparison with radio immuno assay (RIA) and enzme linked immunoabsorbent assay (ELISA). Methods Thirty serum samples from randomly selected patients were collected to test CEA content with ICA,RIA and ELISA respectively.Results The linear range of CEA was 0.1 to 1000 ng/ml for ICA,5 to 80 ng/ml for RIA and 5 to 50 ng/ml for ELISA.The intraassay coefficients of variation (CV) and interassay CV were 1.2% and 4.4% for ICA,3.5% and 8.6% for RIA,and 13.6% and 20.1% for ELISA,respectively.Correlation tests revealed that the results of RIA was more closely correlated with that of ICA than with that of ELISA.Conclusion ICA is shown to be a better method for CEA quantitation than RIA and ELISA in terms of precision and linear range.