MXene@Ni(HITP)@AuNPs combined with NiCo@Fc-MWCNTs-LDH for electrochemical detection of extracellular vesicles.

This study proposed an electrochemical sensor combining Mxene@Ni(HITP)@AuNPs with NiCo@Fc-MWCNTs-LDH for detecting extracellular vesicles (EVs) derived from MCF-7 cells. Mxene exhibits high conductivity and large surface area. Ni(HITP) is a novel conductive metal-organic framework (MOF) with outstanding conductivity, capable of loading more gold nanoparticles (AuNPs) when combined with polyetherimide (PEI). Tetrahedra DNA (TDN) is anchored on the substrate through gold nanoparticles (AuNPs) for the specific capture of EVs, with CD63 aptamers carried at their vertices. In the signal layer, the NiCo@Fc-MWCNTs-LDH loaded with CD63 aptamers was prepared as the electrochemical sensor signal label for EVs detection. This electrochemical sensor exhibits high sensitivity, evidenced by a low limit of detection (LOD) of 13.79 particles/mL and a linear range from 1.6 × 10 to 1.6 × 10 particles/mL, underscoring its potential for early cancer diagnosis.