Mycotoxin-induced logic gates to execute multichannel intelligent display of DNA biocomputations based on symmetric...

Despite significant progress has been made in DNA computations, the intelligent display of logic events remains a big challenge. Herein, we reported a logic system for mycotoxin sensing based on symmetric catalytic hairpin assembly (SCHA) using dumbbell DNA as the self-assembly probes. The mycotoxin-aptamer binding releases the trigger DNA, which can launch the SCHA reaction to produce the long-nicked double-stranded DNA products. The obtained fluorescence signals are used to monitor the logic outputs. The numbers "1" and "0" are used to code the mycotoxin inputs, including deoxynivalenol (DEO), ochratoxin A (OTA), and aflatoxin M1 (AFM1). The outputs are the fluorescence signals, defined as "On" and "Off" states when the fluorescence intensities are higher and lower than the threshold values, respectively. Through simulating single chip microcomputer, the mycotoxin sensing strategy has been further applied to build the multichannel intelligent display of DNA computations. Several logic circuits, including single-channel YES logic circuit, dual-channel FANOUT logic circuit, and three-channel FANOUT logic circuit, were utilized to operate the logic functions. The mycotoxin-induced logic system was successfully used to create a series of images on the basis of appropriate input combinations and biocomputing. The resulting outputs depicted symbols including a number sign, a chuckle face, a smiling face, a mask, and a Super Mario character. Our proposed logic system can not only provide a smart sensing strategy for mycotoxin monitoring, but also can realize the intelligent display of logic events.