Stable Open-Shell Radical Polymers as Multifunctional Platforms for Electronic Memory and Analyte Sensing

Stable nitroxide-functionalized nonconjugated polymers are introduced as a class of redox-active macromolecules uniquely positioned at the intersection of soft materials engineering and functional electronics. The absence of a conjugated backbone proves advantageous rather than limiting: it confers exceptional processability in common solvents and mechanical adaptability that conjugated analogs rarely achieve, thereby enabling direct film deposition onto compliant substrates through scalable solution-based routes. Central to device operation is the chemically reversible single-electron transition inherent to the nitroxide radical unit, which drives reproducible resistive switching under low applied bias while maintaining a substantial ON/OFF current ratio across repeated cycling. This switching characteristic satisfies key benchmarks for non-volatile data retention without the need for inorganic active layers. Beyond memory functionality, the polymer's tolerance of aqueous conditions and tissue-compatible mechanical properties position it as an active material candidate for electrochemical detection in biological microenvironments. Taken together, the findings reframe nonconjugated radical polymers not as structural compromises but as deliberately engineered platforms capable of addressing simultaneous demands in flexible memory and biointegrated sensing.