A multi-thionine DNA network-driven electrochemical aptasensor with dual signal amplification for ultrasensitive...

Au NPs@FGO@Fe MOG were sythesized for its inaugural application in biosensor development and engineered as a novel, highly efficient electrochemical aptasensor for the precise detection of interleukin-6 (IL-6). The aptasensor architecture integrates Au NPs@FGO@Fe MOG as the electrode interface and an anemone-like PtNi nanoclusters@MIL-anchored three-dimensional DNA (PD) network as the signal transduction matrix. The as-prepared Au NPs@FGO@Fe MOG exhibited an exceptionally high specific surface area, excellent electrical conductivity, and robust structural stability, collectively contributing to a pronounced enhancement in the performance of an electrochemical biosensor. The hierarchically PD network provided abundant binding sites for the redox-active probe thionine (Thi), thereby amplifying the electrochemical signal with remarkable efficiency. Under optimized conditions, the aptasensor achieved an impressive detection limit of 0.89 pg/mL. Moreover, the platform demonstrated reliable performance in detecting IL-6 in unspiked human serum samples, with results exhibiting high concordance with those obtained from commercial enzyme-linked immunosorbent assay (ELISA) kits. These findings demonstrate the considerable potential of this platform for rapid, sensitive, and accurate cytokine quantification, offering valuable prospects for clinical diagnostic applications.