Enhanced DNA cryogel platform: Dual-RCA-Driven coloration in situ for portable biosensing

Background Portable biosensing strategies are promising rapid and on-site detection methods, possessing the efficiency and accessibility for detecting target. Hydrogel present numerous advantages in rapid analysis owing to their remarkable biological loading capabilities and optical properties. However, traditional hydrogels suffer from some drawbacks, such as poor signal intensity and slow responsiveness, restricting their further utilization in practice. Results To address these challenges, an enhanced DNA cryogel biosensing platform based on dual-RCA and dual-enzyme had proposed for quantification of zearalenone (ZEN) in this study. The MB@Apt-cDNA probe and DNA cryogel were prepared in advance to provide accurate recognition and portable interface. When ZEN presented, the released cDNA aroused rolling-circle amplification (RCA) to amplify signal, and then introduced dual-enzyme system by coupling glucose oxidase and horseradish peroxidase. On the dual-RCA-based DNA cryogel, the coloration in situ displayed under self-powered H 2 O 2 system. The results identified through visualization, smartphone and color chart, exhibiting a limit of detection (LOD) at 6.95 pg/mL, with detection range between 10 pg/mL to 20 ng/mL. This biosensing showed satisfactory specificity, accuracy, efficiency and accessibility by its application in spiked and real samples. Furthermore, the highlights, including high integration, simplified operation and portable reading, had demonstrated. Significance The enhanced chromogenic cryogel platform can provide by integrating advanced strategies, which may have promising prospects for portable monitoring.