Crystal Phase-Driven MnO₂-DNA as Editable Artificial Messengers Enabling a Bioinspired Array for High-Resolution Biosensing.

Abstract

Enzyme cascade-based bioinspired array hold promise for high-resolution recognition of structurally similar compounds; however, most enzymes lack a direct substrate-to-product relationship, necessitating stable and editable artificial messengers for their integration. Herein, the exposed crystal surfaces of ligand-free manganese dioxide (MnO₂) are found to facilitate efficient single-stranded DNA (ssDNA) adsorption and separation. Theory-guided crystal phase modulation further reveals that β-MnO₂ can capture the phosphate backbone of ssDNA through a surface potential-induced oxygen-vacancy-filling mechanism. Leveraging nuclease's bioactivity, β-MnO₂-ssDNA are engineered on demand as artificial messengers to cascade hydrolases and nucleases via reductive product-mediated self-sacrifice and release of Mn²⁺ and ssDNA. Notably, nucleases can capture organophosphorus (OPs) from phosphorylated hydrolases before their complete aging. Such protein competition among hydrolase-OP-nuclease triggers accumulative differentiation across pathways, improving the resolution for structurally similar OPs. Accordingly, we proposed a gustatory-inspired pathway-signaling-recognition system (GPS), where the GPS-based array delivers differential optical signals via multipathway responses and generates unique digital encoding for precisely discriminating 19 structurally similar OPs. With chlorpyrifos as a representative target, the GPS-based array provides high-resolution qualitative/quantitative assays and supports dynamic degradation monitoring in multidimensional samples. These findings provide inorganic insights into the MnO₂-ssDNA interaction mechanism and establish the GPS-based array as a generalizable paradigm for high-resolution biosensing.