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

Abstract

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 μg/L, respectively. The quantitative detection linear range was 0.01–0.625 μg/L for AFB1, 0.08–2.5 μg/L for OTA, and 0.8–25 μg/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%.