DNAzyme Amplified Aptasensing Platform for Ochratoxin A Detection Using a Personal Glucose Meter

Area of Science:

• Biotechnology
• Biosensor Technology
• Analytical Chemistry

Background:

• Aptamer-based sensors offer high affinity and selectivity for small-molecule detection.
• Current challenges include achieving portable, accurate, sensitive, and affordable detection methods.
• Existing platforms often struggle with sensitivity and practical application in diverse settings.

Purpose of the Study:

• To develop a novel aptasensing platform for sensitive and portable detection of small-molecular targets.
• To enhance signal amplification for improved detection limits.
• To create a versatile platform adaptable for various analytes.

Main Methods:

• Conjugation of biotin-labeled aptamer probes and substrate strands onto magnetic beads.
• Utilizing a DNAzyme strand for signal amplification via iterative substrate cleavage.
• Employing invertase to convert toxin detection into glucose measurement for readout with a portable glucose meter.

Main Results:

• The aptasensor demonstrated high sensitivity in detecting ochratoxin, a common food toxin.
• Achieved a linear detection range spanning 5 orders of magnitude.
• Reported a low detection limit of 0.88 pg/mL with good selectivity.
• The platform showed ease of operation and potential for point-of-care applications.

Conclusions:

• The developed aptasensing platform offers a sensitive, portable, and affordable solution for small-molecule detection.
• The system's modular design allows for adaptation to detect a wide range of analytes by modifying aptamer probes and DNAzyme components.
• This technology holds promise for quantitative analysis in home and point-of-care settings.