Platinum nanoparticles enhanced electrochemiluminescence immunosensor for ultra-trace evaluation of cancerembryonic antigen using MXene@CeO2

Abstract

Early detection of tumor markers is crucial for the screening, diagnosis, and treatment efficacy evaluation of cancer. Electrochemical immunosensors are ideal tools for this purpose due to their high sensitivity and specificity. Here, we reported an ultrasensitive and specific electrochemiluminescence (ECL) immunosensor based on a MXene@CeO2-Pt nanocomposite for early detection of carcinoembryonic antigen (CEA). The fabricated immunosensor was prepared via sequential electrochemical deposition of MXene nanosheets (NSs)@Cerium Oxide (MXene@CeO2) and platinum nanoparticles (PtNPs) on the surface of a graphenized screen-printed carbon electrode (GSPCE). The proposed immunosensor exhibited a limit of detection of 0.098 pg mL- 1 within a concentration range of 0.1 pg mL- 1 to 600 ng mL- 1, demonstrating high sensitivity for healthy human serum and real patient samples. The excellent performance of the developed immunosensor arise from the synergistic combination of graphenized screen-printed carbon electrode with high conductivity and large surface area as well as unique catalytical properties of the MXene@CeO2-Pt nanocomposite. This work not only represents an advancement in MXene@CeO2-based ECL biosensing, but also provides an important milestone in the clinical detection of tumor markers by electrochemical graphenization of SPCE surface using KNO3 as a non-destructive and environmentally friendly method.