A self-assembled DNA double-crossover-based fluorescent aptasensor for highly sensitivity and selectivity in the simultaneous detection of aflatoxin M and aflatoxin B.

Realizing the simultaneous speedy detection of multiple mycotoxins in contaminated food and feed is of great practical importance in the domain of food manufacturing and security. Herein, a fluorescent aptamer sensor based on self-assembled DNA double-crossover was developed and used for effective simultaneous quantitative detection of aflatoxins M and B by fluorescence resonance energy transfer (FRET). Fluorescent dye-modified aflatoxin M and B aptamers are selected as recognition elements and signal probes, and DNA double crosses are consistently locked by the aflatoxin aptamers, which results in a "turn-off" of the fluorescent signal.