Surface-anchored liquid crystal droplets for the semi-quantitative detection of Aflatoxin B1 in food samples

Aflatoxin B1 (AFB1) is a common food mycotoxin that can cause various diseases. Therefore, reliable detection methods are required to ensure food safety against mycotoxins. In this study, we design a liquid-crystal (LC)-based assay for rapid detection of AFB1 in food samples. The surface-anchored LC droplets on glass (5CB_SADrop) are obtained via a solvent evaporation method. The 5CB_SADrop displays a four-leaf clover appearance that corresponds to an escape-radial configuration in a mixture of CTAB and AFB1 aptamer. Interestingly, they adopt a radial configuration in the mixture of CTAB, AFB1, and its aptamer. Using this approach, AFB1 can be detected using only 1 µL of the aqueous solution with a minimum detection concentration of 10 pg/mL. This LC-based sensing platform provides simple operation, remarkable sensitivity, high selectivity, low cost, and excellent portability without the use of any bulky instrument, which is very promising in rapid on-field detection of mycotoxins.