Multiplexed lateral flow immunoassay based on inner filter effect for mycotoxin detection in maize

Multiplexed screening techniques for simple, rapid, and accurate mycotoxin sensing are of great importance. Hence, a multiplexed competitive lateral flow immunoassay (cLFIA) based on inner filter effect (IFE) between flower-like gold nanoparticles and red-emitting quantum dots was developed for the simultaneous detection of aflatoxin B1 (AFB1), ochratoxin A (OTA), and zearalenone (ZEN) in maize. A control line based on a biotin-streptavidin system was developed to ensure that a target independent signal can serve as the reference signal and achieve accurate quantification of multiple targets. The resultant multiplexed IFE-cLFIA test strips exhibited high sensitivities for AFB1, OTA, and ZEN, with LODs of 0.005, 0.04, and 0.4 mu g/L, respectively. The quantitative detection linear range was 0.01-0.625 mu g/L for AFB1, 0.08-2.5 mu g/L for OTA, and 0.8-25 mu g/L for ZEN in the diluted maize extract solution. Recoveries for the three kinds of mycotoxins in maize ranged from 72.92% to 105.80%, with a coefficient of variation below 15.43%.