Epitope-imprinted polydopamine electrochemical sensor for ovalbumin detection.

Area of Science:

• Electrochemistry
• Biosensors
• Materials Science

Background:

• Ovalbumin (OVA) is a common allergen found in various food products.
• Accurate detection of OVA is crucial for food safety and allergic individuals.
• Existing detection methods may lack sensitivity, selectivity, or require complex procedures.

Purpose of the Study:

• To develop a novel, sensitive, and selective electrochemical sensor for OVA detection.
• To utilize epitope-imprinted polydopamine (PDA) for enhanced molecular recognition.
• To validate the sensor's performance for OVA detection in real-world samples like wine.

Main Methods:

• Synthesis of molecularly imprinted PDA on an AuNP-coated screen-printed carbon electrode (SPCE) using OVA IgE-binding epitope as a template.
• Optimization of key parameters including template concentration, electropolymerization cycles, pH, and binding/rebinding times.
• Electrochemical detection of OVA using differential pulse voltammetry (DPV) in a K3Fe(CN)6/KCl supporting electrolyte.

Main Results:

• The developed sensor exhibited high sensitivity towards OVA with a linear range from 23.25 to 232.50 nM (1 to 10 ppm).
• Achieved a low limit of detection (LOD) of 10.76 nM (0.46 ppm) and limit of quantification (LOQ) of 35.87 nM (1.54 ppm).
• Demonstrated excellent selectivity against other proteins (HSA, BSA, LYZ) and successful detection of OVA in wine samples with good recovery (104.74-105.96%).

Conclusions:

• The epitope-imprinted PDA-based electrochemical sensor provides a sensitive, selective, and reliable method for OVA detection.
• The sensor's ability to detect OVA in wine samples highlights its practical applicability in food analysis.
• This approach can be extended to detect other allergenic proteins in the food supply chain, enhancing food safety.