Sensitive amplified luminescent proximity homogeneous assay for the quantitative detection of CA242.

We here developed a sensitive and stable amplified luminescent proximity homogeneous assay (AlphaLISA) method for fast quantification of CA242 in human serum. Donor and acceptor beads modified with carboxyl groups could be coupled with CA242 antibodies after activation in the AlphaLISA method. CA242 was rapidly detected by the double antibody sandwich immunoassay. The method yielded good linearity (>0.996) and detection range (0.16-400 U/mL). The intra-assay precisions of CA242-AlphaLISA were between 3.43% and 6.81% (< 10%), and the inter-assay precisions were between 4.06% and 9.56% (< 15%). The relative recoveries ranged from 89.61% to 107.29%. Detection time for the CA242-AlphaLISA method was only 20 min. Moreover, results of CA242-AlphaLISA and time-resolved fluorescence immunoassay had satisfactory correlation and consistency (ρ = 0.9852). The method was successfully applied to the analysis of human serum samples. Meanwhile, serum CA242 has a good detection value in the identification and diagnosis of pancreatic cancer and the monitoring of disease degree. Furthermore, the proposed AlphaLISA method is expected to be an alternative to traditional detection methods, laying a good foundation for the further development of kits to detect other biomarkers in future studies.