One-step strand displacement-mediated nucleic acids signal-amplified analytical strategy based on...

DNA nanostructure, as polymeric material with remarkable molecular recognition property, has been widely used in bioassay. However, it still faces some challenges to overcome complexity of signal-amplified strategies and to realize efficient separation of reaction products. Herein, we present an innovative signal-amplified approach by integrating the toehold-mediated strand displacement reaction with DNA tile self-assembly technology to construct superparamagnetism-functionalized DNA polymeric materials, establishing a new signal-amplified analytical strategy for nucleic acids. This strategy enables highly sensitive, rapid, and efficient nucleic acid detection, making it a promising candidate for point-of-care testing (POCT). The analytical performance of this strategy was validated using target DNA (tDNA) and PIWI-interacting RNA-36026 (piRNA-36026), achieving limits of detection (LOD) of 2.4 × 10^-10 M and 2.7 × 10^-10 M. Moreover, it successfully detected single-base mutations and demonstrated stability over seven days. Comparative experiments confirmed the superior signal-amplified efficiency of DNA arrays. Recovery experiments yielded recoveries of 88.53 %-101.89 % for tDNA and 87.58 %-108.61 % for piRNA-36026. Ultimately, the feasibility of this strategy for real-world applications was validated through detecting piRNA-36026 in cell lysates. In conclusion, this work introduces an innovative and efficient signal-amplified method, while expanding the application prospects of multifunctional DNA polymeric materials in biomedical diagnostics.