Visual biosensor using CRISPR and nanozyme to detect microRNA-21

A detection limit of 420.0 fM for tumor-associated miRNA-21 is achieved using a CRISPR/Cas12a-nanozyme visual biosensor.

• MicroRNAs, particularly miRNA-21, are important biomarkers for aggressive tumors.
• The biosensor utilizes a peroxidase-like nanozyme linked to magnetic beads for detection.
• Recognition of miRNA-21 triggers a reaction that amplifies DNA, activating the CRISPR/Cas12a system.
• The activated Cas12a cleaves DNA linkers, releasing the nanozyme to produce a visible color change.
• This method offers a direct and sensitive visual detection mechanism for nucleic acids.

Simplified