Magnetic copper silicate and boronic acid-conjugated AuNCs@keratin-based electrochemical/fluorescent dual-sensing for carcinoembryonic antigen

Boronic Acid Sensitivity, selectivity, and reliability are of great importance for tumor diagnosis. Herein, we proposed a novel electrochemical and fluorescent dual-sensing strategy to detect carcinoembryonic antigens (CEA). To this end, monodisperse spindle-like magnetic copper silicate (FeOx@C@CS) was prepared with multiple active sites to immobilize the CEA antibody. Moreover, magnetic properties improved the anti-interference ability and sensitivity to endow the assay for complex samples. In addition, boronic acid-conjugated gold nanocluster (AuNCs@keratin-BA) was prepared as an electrochemical and fluorescent dual-signal indicator. Thus, the sandwich structure of FeOx@C@CS/CEA/AuNCs@keratin-BA was formed for electrochemical/fluorescent dual-modality assay. Under optimal conditions, the quantitation range of 12.5 fg mL-1-37.5 pg mL-1 and detection limit of 4.3 fg mL-1 were obtained for the electrochemical strategy. The fluorescence detection owned the linear range of 0.05 pg mL-1-7.5 pg mL-1 with a detection limit of 0.025 pg mL-1. Dual-modality assay improved the accuracy and efficiency of CEA detection to meet the requirement of tumor diagnosis, while chemical identification and signal transduction lay an important foundation for engineering advanced nano materials for clinical applications.