Target responsive-regulated CRISPR/Cas12a electrochemiluminescence sensing of salmonella typhimurium integrating ultrafine Pt NCs-anchored MXenes-boosted luminol/O2 system.

Salmonella typhimurium (S. typhimurium), as common and highly pathogenic foodborne pathogen, poses a significant risk to public safety worldwide. The development of highly sensitive, rapid and on-site method for S. typhimurium analysis is urgently needed to prevent bacterial infections. Herein, we introduced a CRISPR/Cas12a-driven electrochemiluminescence (ECL) sensor based on luminol/O2 binary systems for S. typhimurium detection, employing ultrafine Pt nanoclusters-anchored 2D delaminated-MXenes (Pt NCs/D-MXenes) as the co-reactant accelerator. The ultrathin D-MXenes support regulates the size and dispersibility of Pt NCs and facilitates the full exposure of active sites, and synergistic interactions between D-MXenes and Pt NCs improves electrocatalytic properties toward the reduction of O2, which promotes the generation of ROS for boosting ECL emission. Using target responsive-regulated CRISPR/Cas12a system, the ECL sensor for S. typhimurium showed a broad concentration range from 101 to 106 CFU/mL and limit of detection of 6 CFU/mL, with satisfactory recoveries in spiked-actual samples.