CRISPR-powered microfluidic biosensor for preamplification-free detection of ochratoxin A

Area of Science:

• Biotechnology
• Nanotechnology
• Analytical Chemistry

Background:

• CRISPR-Cas systems offer powerful detection capabilities but often require pre-amplification, increasing complexity and time.
• Developing sensitive and rapid detection methods is crucial for on-site food safety analysis.

Purpose of the Study:

• To develop a pre-amplification-free CRISPR-Cas system for ochratoxin A detection.
• To utilize Pd@PCN-222 nanozyme as a reporter for enhanced electrochemical signal amplification.
• To establish a microfluidic electrochemical chip for on-site ochratoxin A detection.

Main Methods:

• A CRISPR-Cas system was constructed for ochratoxin A detection.
• Pd@PCN-222 nanozyme was used to label single-stranded DNA as a reporter (Pd@PCN-222 CRISPR nanozyme).
• A microfluidic electrochemical chip was developed for on-site detection.

Main Results:

• The Pd@PCN-222 CRISPR nanozyme exhibited high catalytic activity, significantly amplifying the electrochemical signal.
• The need for pre-amplification was successfully eliminated.
• An outstanding detection limit of 1.21 pg/mL for ochratoxin A was achieved.

Conclusions:

• The developed CRISPR-Cas system with Pd@PCN-222 nanozyme offers a sensitive and efficient method for ochratoxin A detection.
• Eliminating pre-amplification simplifies the detection process and reduces analysis time.
• The microfluidic electrochemical chip platform shows great potential for practical on-site food safety hazard detection.