Color-Potential-Resolved Nanoreactor Luminophore for Bipolar Electrode Electrochemiluminescence Biosensing and Imaging Assay of Dual DR Genes

High resolution and intense signal are challenges in electrochemiluminescence (ECL) imaging analysis. In this study, two novel color-potential-discriminated nanoreactor luminophores with high intensity ECL were innovatively prepared via a nanoconfinement effect, which was used to construct a sensitive bipolar electrode (BPE)-ECL biosensor by electrocatalyst amplification for ECL detection and imaging of mecA and ARG_AMP gene. First, a new ZrMOF with a porous structure was employed as a microreactor to accommodate abundant luminophor, Ru(bpy)₃²⁺ or luminol molecules, which not only produced an amplified high-strength ECL signal but also realized sensitive color discrimination. Thus, the two nanoreactor luminophors were combined with an outstanding electrocatalyst, Pt@PMOF(Fe), to fabricate a color-discriminated BPE biosensor for ECL sensing of dual targets. The amplification product output DNA 1 of target mecA introduced Pt@PMOF(Fe) into the A hole of channel 1 in BPE. During positive potential scan, the polarity of A hole was negative, so the excellent electrocatalytic performance promoted the decomposition of H₂O₂ and accelerated the electron transfer of BPE, which greatly improved the red ECL signal of RuMOFs for mecA detection. In negative-potential sweep, the amplification product of ARG_AMP introduced the electrocatalyst into B-hole with negative polarity in channel 2, so the blue ECL signal of L@ZrMOFs was enhanced for ECL detection and phone imaging assay of ARG_AMP. This work is for the first time to apply the color-potential-resolved nanoreactor luminophore into BPE-ECL sensing imaging analysis, which opened new techniques and applications in BPE-ECL analysis.