LSPR-driven potential-resolved ECL aptasensor with integrated screening-detection for ochratoxin A in maize.

Area of Science:

• Analytical Chemistry
• Nanotechnology
• Biosensors

Background:

• Ochratoxin A (OTA) is a prevalent mycotoxin posing significant health risks.
• Sensitive and selective detection methods for OTA in complex matrices are crucial.

Purpose of the Study:

• To develop a potential-resolved electrochemiluminescence (PRECL) aptasensor for sensitive ochratoxin A (OTA) detection.
• To integrate highly ordered anodic aluminum oxide (AAO) nanopores and core-shell Au@Ag nanoparticles for enhanced sensing performance.

Main Methods:

• Fabrication of a PRECL aptasensor using AAO nanopores and Au@Ag nanoparticles.
• Utilizing tetrahedral DNA nanostructures for aptamer immobilization and OTA recognition.
• Employing ruthenium-silica NPs/K2S2O8 system for enhanced electrochemiluminescence (ECL) signals.
• Leveraging the screening effect of AAO to minimize interference.

Main Results:

• Achieved significant enhancement in both cathodic and anodic ECL emissions due to the localized surface plasmon resonance of Au@Ag NPs.
• Demonstrated efficient recognition of OTA molecules by orderly immobilized aptamers.
• Successfully eliminated interference from large-scale molecules via the AAO screening effect.
• Established a linear detection range of 0.01-80 μg/kg for OTA.
• Obtained a low limit of detection of 1.4 × 10⁻⁴ μg/kg.

Conclusions:

• Pioneered a PRECL aptasensor design with integrated screening-detection dual functionality.
• The developed aptasensor shows high promise for rapid and sensitive detection of trace targets in complex matrices.
• This approach offers a novel strategy for the development of advanced biosensing platforms.