Hualin Guo, Pengfei Ma, Yu Li, Chen Pe, Zhouping Wang
Herein, we present a novel dual-mode biosensor for ultrasensitive chloramphenicol detection using an engineering split aptamer, which is rationally designed via molecular dynamics simulation to identify key binding bases. Upon target-induced assembly, the split fragments simultaneously enhance the fluorescence of silver nanoclusters and recover the peroxidase activity of the ZIF-67 nanoflower (ZNF), enabling fluorometric/colorimetric dual-readout. Under optimal conditions, the biosensor demonstrated outstanding analytical performance with fluorescent and colorimetric detection limits of 0.011 and 0.021 ng/mL, respectively. It was also successfully applied to the accurate detection of CAP in milk, honey, fish, and river water samples with satisfactory recoveries. This work not only provides a robust and reliable sensing platform for food safety monitoring but also offers a general MD-guided strategy for the rational design of split aptamers.