An aptamer-based lateral flow test strip was developed for the detection of zearalenone (ZEN). This assay was based on the competition for the aptamer between ZEN and its complementary sequence. Several experimental conditions that could influence sensitivity have been investigated, including the concentration of aptamer and NaCl used in the probe preparation, the mole ratio of streptavidin and biotinylated DNA used in the preparation of test line and control line, and the loading quantity of gold nanoparticles-aptamer conjugates (AuNPs-Apt). Under the optimal experimental conditions, we successfully detected ZEN within a detection range of 5-200 ng/mL and the visual limit of detection of 20 ng/mL. This aptamer-based strip was successfully applied to the determination of ZEN in spiked corn samples, and the recoveries were from 93.4% to 114.2%. All detections can be achieved within 5 min. The results demonstrated that the developed aptamer-based lateral flow test strip is a potential alternative tool for the rapid and sensitive detection of ZEN.
Keywords: aptamer; gold nanoparticles; lateral flow test strip; zearalenone.