Solid-phase extraction of ochratoxin A from wine based on a binding hexapeptide prepared by combinatorial synthesis

Area of Science:

• Analytical Chemistry
• Food Safety
• Biochemistry

Background:

• Mycotoxins, such as ochratoxin A (OTA), pose a significant risk to food and beverage safety.
• Accurate quantification of OTA in complex matrices like wine is crucial for regulatory compliance and consumer protection.
• Existing methods for OTA detection and extraction can be costly or complex.

Purpose of the Study:

• To synthesize a hexapeptide library using combinatorial chemistry.
• To identify a specific peptide with high affinity for ochratoxin A (OTA).
• To develop a novel solid-phase extraction (SPE) method for OTA quantification in wine using the identified peptide.

Main Methods:

• Combinatorial synthesis was employed to create a hexapeptide library.
• Peptide-OTA binding affinity was assessed, identifying a Ser-Asn-Leu-His-Pro-Lys hexapeptide with K(eq)=3.4 x 10(4) M(-1).
• An immunoaffinity-like stationary phase functionalized with this peptide was developed for SPE.

Main Results:

• The Ser-Asn-Leu-His-Pro-Lys hexapeptide demonstrated significant affinity for ochratoxin A.
• The developed SPE method allowed for OTA quantification in wine down to 0.10 microg l(-1).
• High recovery rates (94.7% and 98.4% at 2.0 and 4.0 microg l(-1) OTA, respectively) were achieved without matrix interference.

Conclusions:

• A synthetic hexapeptide-based stationary phase offers an effective alternative for ochratoxin A extraction.
• This method provides a reliable and efficient approach for quantifying OTA in wine samples.
• The performance of this novel SPE method is comparable to established immunoaffinity extraction techniques.