An Immuno-Separated Assay for Ochratoxin Detection Coupled with a Nano-Affinity Cleaning-Up for LC-Confirmation

Area of Science:

• Analytical Chemistry
• Biotechnology
• Immunosensing

Background:

• Ochratoxin A is a prevalent mycotoxin with significant health implications.
• Accurate and sensitive detection methods are crucial for food safety and quality control.
• Existing detection methods can be time-consuming or require specialized equipment.

Purpose of the Study:

• To develop a novel immuno-separated assay for ochratoxin A detection.
• To couple this assay with nano-affinity cleanup for enhanced Liquid Chromatography (LC) confirmation.
• To provide a sensitive, efficient, and reliable method for ochratoxin A quantification.

Main Methods:

• Immuno-fluorescent reporters were created by modifying ochratoxin A with quantum dot beads.
• Immuno-magnetic adsorbents were prepared by conjugating Fe3O4 magnetic nanoparticles with protein G.
• Immuno-separation was achieved using magnetic separation, where released fluorescent reporters correlated with ochratoxin A concentration.
• Eluted ochratoxin A was analyzed using LC for confirmation.

Main Results:

• The developed assay demonstrated a quantitative range of 0.03-100 ng/mL for ochratoxin A.
• Recoveries for spiked samples were between 78.2% and 91.4%, with relative standard deviations (RSD) of 11.9%–15.3%.
• Statistical analysis showed no significant difference compared to High-Performance Liquid Chromatography with Fluorescence Detection (HPLC-FLD) using commercial affinity columns.

Conclusions:

• The developed immuno-separated assay coupled with nano-affinity cleanup is a viable and effective method for ochratoxin A detection.
• The assay offers a sensitive and reliable alternative for ochratoxin A quantification.
• This approach facilitates accurate ochratoxin A analysis with potential for broader application in food safety.