BE-CATCH: Bioamplifier-Equipped CRISPR-Cas12a Transduction System Coupled with Commercial Pregnancy Test Strips to...

Area of Science:

• Biomedical Diagnostics
• Molecular Biology
• Biosensing Technologies

Background:

• Point-of-care testing (POCT) aims for portable, affordable diagnostics by repurposing commercial equipment.
• Existing methods for POCT often involve complex steps like target-specific probe conjugation.
• Pregnancy test strips (PTS) offer a low-cost, accessible platform but require adaptation for broader applications.

Purpose of the Study:

• To develop a universal, separation-free POCT strategy adaptable to various targets.
• To simplify the detection process on PTS by eliminating intricate conjugation steps.
• To enhance the sensitivity and user-friendliness of PTS-based diagnostics.

Main Methods:

• Introduced the bioamplifier-equipped CRISPR-Cas12a transduction system coupled with PTS (BE-CATCH).
• Utilized a novel signal output probe that replaces traditional hCG conjugation on PTS.
• Employed strand displacement amplification (SDA) for signal amplification and CRISPR-Cas12a for target-triggered trans-cleavage.
• Implemented a signal-on detection mechanism for colorimetric readout on PTS.

Main Results:

• Demonstrated that a goat antimouse IgG can trigger a color change on PTS, replacing hCG.
• The BE-CATCH strategy achieved boosted sensitivity and specificity compared to conventional methods.
• Successfully detected specific biomarkers, including miR-155 and flap endonuclease 1, showcasing versatility.
• The system maintained a user-friendly, signal-on detection mode.

Conclusions:

• The BE-CATCH strategy offers a versatile and simplified approach for POCT using PTS.
• This method broadens the applicability of PTS beyond pregnancy testing for diverse biomedical diagnostics.
• BE-CATCH presents an appealing option for developing affordable and accessible POCT devices.