Functionalized DNA mimic of GFP based on the molecule-activated chromophore derivative for hydrogen peroxide detection

Hydrogen peroxide (H₂O₂) plays a pivotal role in both physiological and pathological processes, which attracted considerable attention to its content analysis. Detection of certain small molecules based on DNA/RNA mimics of green fluorescent protein (GFP mimics) has been preferentially constructed due to its high specificity, excellent optical properties, and high stability. However, there is a dearth of functional GFP mimics that can be directly activated by these targets. Herein, an H2O2-activated DNA mimic of GFP (HDG) has been proposed through primarily remolding the GFP chromophore derivative named 3,5-difluoro-4-hydroxybenzylidene imidazolidinone (DFHBI) with phenyl boronate group (PB-DFHBI) and then forming the HDG by adding the truncated Lettuce DNA aptamer (tLet-10) to reveal the specifically fluorescent response toward H₂O₂. In this sensing method, the fluorescence of PB-DFHBI is markedly declined with PB group lock by restricting its intramolecular charge transfer (ICT) process, while the presence of H2O2 will activate a cascade reaction to remove the PB group in HDG, resulting in a high-contrast and turn-on fluorescence. The unique emitting mechanism triggered by H₂O₂ endows HDG with stable, rapid response, high sensitivity, and specific detection performances, exhibiting a low detection limit of 0.59 μM and a comprehensive linear range of 1–1000 μM. Moreover, HDG was allowed to realize the reliable and accurate analysis of spiked H2O2 in beverage and water samples. It is believed that the well-designed HDG will provide a promising way to establish new sensing strategies for certain target analyses and expand their applications of GFP mimics-based sensing platforms. [Display omitted] •Achieving the H2O2-responsive GFP derivatives.•Constructing a novel H₂O₂-responsive fluorescent sensing assay.•Achieving the turn-on, rapid, and sensitive detection performances.•Realizing the H2O2 detection in water and beverages.