Guoqi Ding, Yulin Li, Yao Xiao, Yanru Li, Jiale Yang, Rujian Zhao, Yidan Tang, Bingling Li
A lock-and-key aptamer-CRISPR/Cas12a strategy was developed to convert antibiotic recognition into signal-off fluorescence. Antibiotic binding disrupted the locking domain-maintained stem-loop structure, suppressed T4 DNA polymerase-mediated activator generation and inhibited Cas12a trans-cleavage, enabling selective antibiotic detection and providing a programmable strategy for small-molecule sensing.