A Novel Electrochemiluminescence Janus Emitter for Dual‐Mode Biosensing

Abstract A novel electrochemiluminescence (ECL) Janus emitter realizes dual‐mode biosensing for multiple disease‐related biomarkers from cells. Each Janus emitter consists of ruthenium (II) complex and luminol polymer doped hemispheres that are spatially separated but function simultaneously, generating intense dual‐ECL emissions. This design effectively eliminates optical and electrochemical interferences between different ECL mono‐luminophores in comparison with the homogenous nanostructures, thereby improving ECL efficiency and detection sensitivity. Accordingly, the ECL Janus emitters provide a proof of concept for the construction of the ratiometric ECL sensing of H 2 O 2 . Furthermore, this Janus emitter enables simultaneous identification and quantification of the intracellular cancer‐related dual microRNAs. This work not only inspires the development of ECL Janus emitters, but also highlights their potential in bioanalysis and clinical diagnosis in the future.