Electrochemiluminescent biosensor based on ECL-RET between Ru@TiO2-MXene and Pd@UiO-66-NH2 for the detection of carcinoembryonic antigens

Carcinoembryonic antigen (CEA) is often employed as a crucial tumor marker for both colon and rectal cancer. The assessment of CEA levels holds significant therapeutic importance in the diagnosis of these malignancies. In this study, an electrochemiluminescence immunosensor with a signal off was ingeniously designed with Ru@TiO2-MXene as the base material of the energy donor, and Pd@UiO-66-NH2 as the marker of the energy acceptor. This immunosensor was constructed based on the strong interaction between the two components of ECL-RET. Remarkably, TiO2-MXene exhibits favorable film-forming properties and electrical conductivity while effectively immobilizing Ru(bpy)32+. On the other hand, Pd@UiO-66-NH2 has excellent biocompatibility and light absorption, making it an ideal choice for use as a secondary antibody marker. The electrochemiluminescence immunosensor constructed exhibits an extensive detection range of 1 × 10-5 ng·ml-1 to 80 ng·ml-1 and a narrow detection limit of 2.65 fg·ml-1. The novel electrochemiluminescence immunosensor, as presented in this investigation, introduces a distinct methodology for CEA detection, carrying immense clinical significance in the field of colon and rectal cancer diagnosis.