Detection of multiple mycotoxins based on catalytic hairpin assembly coupled with pregnancy test strip

Various mycotoxins are widely present in crop products, which cause serious harm to human and animals. In this study, combining the specific recognition of aptamer with catalytic hairpin assembly (CHA) strategy, the pregnancy test strip is used to detect multiple mycotoxins. The signal amplification can be further achieved through following enzymatic reaction to increase sensitivity. In the experiment, there is no need to assemble test strip as well as prepare and purify antibody/hapten. It only requires to couple human chorionic gonadotropin (hCG) with DNA probe to realize the target determination via CHA process and enzymatic signal amplification on the test strip. Under optimal conditions, using the CHA based pregnancy test strip detection platform, the visual limits of detection for aflatoxin B1, ochratoxin and zearalenone can be obtained within 15 min, which are 20, 50 and 20 pg/mL, respectively. The detection results of the spiked samples show that the platform possesses satisfied accuracy, reproducibility and practicability. The method has facile scheme, low cost and good design versatility, and reveals potential application prospects in high sensitivity, low cost, and convenient detection of mycotoxins.