miR-Cabiner: A Universal microRNA Sensing Platform Based on Self-Stacking Cascaded Bicyclic DNA Circuit-Mediated CRISPR/Cas12a

CRISPR/Cas12a-based diagnostics have great potential for sensing nucleic acids, but their application is limited by the sequence-dependent property. A platform termed miR-Cabiner (a universal <u>miR</u>NA sensing platform based on self-stacking <u>ca</u>scaded <u>bi</u>cyclic D<u>N</u>A circuit-m<u>e</u>diated C<u>R</u>ISPR/Cas12a) is demonstrated herein that is sensitive and universal for analyzing miRNAs. This platform combines catalytic hairpin assembly (CHA) and hybrid chain reaction (HCR) into a unified circuit and finally cascades to CRISPR/Cas12a. Compared with the CHA-Cas12a and HCR-Cas12a systems, miR-Cabiner exhibits a significantly higher reaction rate. Panels of miRNAs (miR-130a, miR-10b, miR-21, and miR-1285), which are associated with diagnosis, staging, and prognosis of breast cancer, are designed to demonstrate the universality of miR-Cabiner. Four miRNAs can be detected to the fM-level by simply tuning the sequence in CHA components. Additionally, miRNA panel analysis also shows high accuracy in practical samples. This universally applicable platform for detecting miRNA may serve as an excellent tool for clinical diagnosis.