Fast Deoxynivalenol Determination in Cereals Using a White Light Reflectance Spectroscopy Immunosensor

Area of Science:

• Food Science
• Analytical Chemistry
• Biosensors

Background:

• Deoxynivalenol (DON) is a prevalent mycotoxin in global wheat and maize supplies.
• DON poses chronic and acute toxicity risks, necessitating rapid detection methods.
• Existing methods for DON determination can be time-consuming and require laboratory settings.

Purpose of the Study:

• To develop and validate a fast, sensitive, and label-free method for on-site DON determination.
• To utilize White Light Reflectance Spectroscopy (WLRS) for DON quantification in grain matrices.
• To assess the feasibility of using buffer-based calibration for real-world sample analysis.

Main Methods:

• Development of an optical immunosensor employing WLRS technology.
• Optimization of extraction protocols, with distilled water yielding >90% recovery.
• Assay validation using spiked wheat and maize samples, with analysis time of 12 minutes.

Main Results:

• The WLRS immunosensor achieved a quantification limit of 2.5 ng/mL in buffer (125 μg/kg in whole grain).
• Extraction with distilled water provided the highest DON recovery rates (>90%).
• Calibration curves in buffer and grain extracts were comparable, enabling simplified analysis.

Conclusions:

• The developed WLRS immunosensor offers a rapid and sensitive method for label-free DON detection.
• The assay's performance, speed, and portability support its application for on-site food safety monitoring.
• The method's sensitivity surpasses regulatory limits for DON in grains intended for consumption.