Determination of carcinoembryonic antigen (CEA) by label-free electrochemical immunosensor using functionalized boron nitride nanosheets

In this study, a simple, specific and sensitive immunosensor for CEA detection was prepared based on BN nanosheets. Lewis acid-base interaction was sufficient for the immobilization of anti-CEA used as an antibody on the electrode surface without an activation agent. This immunosensor could be used for CEA determination without the need to use any label or secondary antibody. With its epedance-based recognition mechanism, this immunosensor offered a low LOD value of 0.017 ng/mL and a wide measurement range of 0.1-500 ng/mL and could be used for a long time. The analytical performance of this immunosensor is higher than the biosensors prepared in the literature. Compared to commercially available kits, it is attractive because it is cheap, simple and analyzes in a short time. This immunosensor, which has high selectivity against CEA in the presence of competitive agents in commercial human serum, has a high potential for clinical applications.