Abstract:Ochratoxin A (OTA) can contaminate wheat, thus posing a serious food safety issue. On-site rapid detection of OTA requires stable and reliable equipment and detection methods. Current pretreatment methods require extensive equipment, involve long detection times, and are susceptible to human interference. In this study, an integrated microfluidic chip with various functional chambers was proposed to achieve synchronous, rapid pretreating of wheat. Pretreated test droplets are added to electrodes modified with antibodies for OTA detection through impedance sensing. The whole process only requires 15 minutes. Quantitative detection of OTA through impedance sensing exhibited a good linear relationship (R2=0.98), low detection limit (0.05 μg/mL), and stable recovery (88.25%~112.36%). Testing of other confounding toxins reveals that the combined use of the pretreatment microfluidic chip and impedance sensing has good specificity for OTA detection. The proposed method demonstrates higher specificity, reliability, and stability than conventional pretreatment methods and liquid chromatography-mass spectrometry. By combining a microfluidic chip with impedance sensing, this method meets the basic pretreatment requirements for detecting OTA in wheat and other foods and enables rapid detection of OTA. This efficient and convenient method provides insight into the development of systems for food quality and safety and early disease monitoring.
