Electrochemical Immunosensor based on hierarchical au Nanoflowers modified screen-printed carbon electrode for sensitive and specific detection of CEA

Uniform hierarchical AuNFs are in-situ fabricated on SPCE via facile one-step electrodeposition. • AuNFs provide abundant accessible binding sites for antibody immobilization and efficient electron-transfer pathways. • The developed immunosensor achieves ultra-sensitive CEA detection with an ultra-low LOD. • The as-prepared immunosensor exhibits favorable reproducibility and satisfactory long-term storage stability. This study reports a highly sensitive electrochemical immunosensor based on branched hierarchical gold nanoflowers (AuNFs) for the selective detection of carcinoembryonic antigen (CEA). Uniform AuNFs were synthesized by optimized electrochemical deposition parameters on the screen-printed carbon electrode (SPCE). The distinct hierarchical branched structure of AuNFs endows the electrode interface with abundant uniformly distributed active sites and efficient electron-transport pathways. By integrating MUA self-assembly with EDC/NHS-mediated covalent antibody immobilization, a highly specific and stable electrochemical immunosensor was successfully developed for ultrasensitive CEA detection. The proposed immunosensor achieves a wide linear detection range from 0.1 to 100,000 pg·mL −1 and a low limit of detection (LOD) of 0.069 fg·mL −1 for CEA detection. Furthermore, the immunosensor exhibits excellent selectivity, reproducibility, and long-term storage stability, enabling reliable quantification of CEA in biological samples. This study demonstrates that the AuNFs-modified SPCEs immunosensor is a promising high-performance platform for point-of-care (POCT) tumor biomarker detection, with great application potential in early clinical cancer screening and postoperative dynamic monitoring. AuNFs modified screen-printed carbon electrodes (SPCEs) possesses excellent electrical conductivity and plasticity, which facilitates the construction of CEA-specific sensing interfaces and improve detection sensitivity. Download: Download high-res image (175KB) Download: Download full-size image