FSCV/ECL dual-mode detection of circulating tumor cells based on multi-functionalized 2D bionanomaterials

Herein, a fast scan cyclic voltammetry (FSCV)/electrochemiluminescence (ECL) dual-mode electrochemical biosensor based on multi-functionalized two-dimensional (2D) bionanomaterials MXene@Fe3O4-APTs as the capture unit and BPNS@CuNPs-APTs as the signal unit, was designed for the detection of human circulating tumor cell (CTC) A549. In presence of A549, a Faraday cage-type electrochemical biosensor was one-step constructed by forming a complex "capture unit-A549-signal unit". A549 cells could be captured with high efficiency, and dual-mode detected with high sensitivity. Under optimal experimental conditions, the linear range of FSCV and ECL was 101–108 cells/mL, and the detection limit was 3 cells/mL. And, the stability, reproducibility and selectivity of the sensor were all satisfied. The dual-mode detection of intact CTC by electrochemical biosensor was achieved for the first time, the feasibility and reliability of which were verified by analyzing A549 in spiked and real human whole blood samples, suggesting a broad application prospect in clinical diagnosis.