Bifunctional probe-assisted hybridization chain reaction for circular RNA detection and live-cell imaging

Circular RNA (circRNA) is considered as a promising biomarker for various diseases owing to its unique functions and stable structure in biological circumstances. Nonetheless, homologous linear RNA always causes detection errors, posing a key challenge in effective circRNA assays for clinical applications. Herein, we present a novel method to directly analyze circRNA, eliminating homologous linear RNA interference. A dual-function circRNA-identifying hairpin (ih) probe is designed, which identifies target circRNA and initiates the subsequent hybridization chain reaction amplification. This method provides highly sensitive live-cell circRNA imaging capability and can directly monitor circRNA levels in biological samples, showing great promise for the analysis of low-abundant circRNA in clinical applications.