Self-Assembled Chemiluminescent Nanoprobes Based on α,α-Dicyanoolefins: Leveraging a Dioxetane "Funnel" for High-Contrast Inflammation Imaging

Abstract

Although peroxynitrite (ONOO-) chemiluminescence (CL) imaging offers near-zero background sensitivity for in vivo sensing, developing CL probes remains a formidable challenge due to the limited repertoire of chemiluminescent scaffolds and boronate-related cross-reactivity. Herein, we report the rational design of self-assembled chemiluminescent nanoprobes utilizing an α,α-dicyanoolefin scaffold. The optimal candidate, YMTPT-NPs, spontaneously forms stable nanoparticles in water and achieves orthogonal ONOO- specificity via its C=C bond of α,α-dicyanoolefin, eliminating H2O2 interference. Experimental and density functional theory (DFT) calculations elucidate that ONOO- attack forms a dioxetane intermediate, triggering sequential O–O cleavage to access an S1–S0 near-degenerate "funnel" and subsequent excited-state C–C cleavage. This mechanism efficiently channels chemical energy to drive robust intermolecular CRET within the confined nano-architecture. In a murine acute arthritis model, YMTPT-NPs exhibited an extended functional imaging window (>15 min) and a superior signal-to-background ratio (SBR = 31.38). This study establishes a robust supramolecular paradigm for constructing CL probes that combine practical signal duration, superior specificity, and red-shifted emission for precision in vivo imaging of inflammation.