Double hook-type aptamer-based colorimetric and electrochemical biosensor enables rapid and robust analysis of EpCAM expression

作者：Zhuoliang Hu, Zelin Yang, Mengjie Chen, Wen Chen, Wenjuan Ma, Jing Lü, Duanping Sun · 发表于：Biosensors and Bioelectronics · 年份：2024 · DOI：10.1016/j.bios.2024.116717 · 被引用次数：14 · 研究领域：Advanced biosensing and bioanalysis techniques、RNA and protein synthesis mechanisms、RNA Interference and Gene Delivery

Epithelial cell adhesion molecule (EpCAM), which is overexpressed in breast cancer cells and participates in cell signaling , migration, proliferation, and differentiation, has been utilized as a biomarker for cancer diagnosis and therapeutic prognosis. Here, a dual-signal readout nonenzymatic aptasensor is fabricated for the evaluation of EpCAM at the level of three breast cancer cell lines. The central principle of this enzyme-free aptasensor is the use of double hook-type aptamers (SYL3C and SJ3C2)-functionalized magnetic iron oxide (Fe 3 O 4 ) as capture probes and quasi-CoFe prussian blue analogs (QCoFe PBAs) as nonenzymatic signal probes for colorimetric and electrochemical analysis. Following ligand detachment, the CoFe PBA was transformed to QCoFe PBA (calcined at 350 °C for 1 h), with its metal active sites exposed by controllable pyrolysis . We found that the enhanced sensitivity was attributed to the resonance effect of QCoFe PBA with the remarkable enzymatic properties. The dual-signal readout nonenzymatic aptasensor exhibited limits of detection for EpCAM as low as 0.89 pg mL −1 and 0.24 pg mL −1 , within a wide linear range from 0.001 to 100 ng mL −1 , respectively. We successfully employed this nonenzymatic aptasensor for monitoring EpCAM expression in three breast cancer cell lines, which provides an economical and robust alternative to costly and empirical flow cytometry. The dual-signal readout nonenzymatic aptasensor provides rapid, robust, and promising te...