Advances in CRISPR/Cas13a-based biosensors for non-coding RNA detection

Non-coding RNAs play crucial roles in disease initiation and progression, making them promising biomarkers for early diagnosis and treatment monitoring. Conventional nucleic acid diagnostic methods, including polymerase chain reaction (PCR), next-generation sequencing (NGS), and enzyme-linked immunosorbent assay (ELISA), alongside emerging techniques such as single-molecule fluorescence in situ hybridization (smFISH), nanopore sequencing, and single-cell RNA sequencing (scRNA-seq), face inherent limitations in detecting regulatory non-coding RNAs. These challenges include laborious workflows, prolonged processing times, and technical complexities, hindering their broad applicability in rapid and high-throughput RNA analysis. CRISPR/Cas13a-based biosensors, integrated with various signal transduction systems-such as fluorescence, electrochemistry, colorimetry, surface-enhanced Raman spectroscopy (SERS)-show great promise for real-world diagnostic applications. This review provides a comprehensive overview of the CRISPR/Cas13a-mediated RNA detection mechanism, the development of CRISPR/Cas13a-based biosensors, and their integration with innovative signal detection methods. Additionally, we highlight the progress in portable detection devices, including lateral flow assay strips and smartphone-based platforms. Finally, the review discusses the current challenges and future prospects of CRISPR/Cas13a-based biosensors, particularly in the context of clinical diagnostics and personalized medicine.