Dual aptamer-regulated activation of CRISPR-Cas12a assisted self-enhanced electrochemiluminescence sensor for AFB1 detection based on ultrafine Au NCs-anchored g-C3N4

Aflatoxin B1 (AFB1), the most toxic mycotoxin among aflatoxin family, which presents a risk to food safety and human health at a trace level. Herein, the self-enhanced electrochemiluminescence (ECL) emitters of Au nanoclusters-anchored g-C 3 N 4 nanosheet (Au NCs@g-C 3 N 4 ) were synthesized, in which the Au NCs as a co-reaction accelerator enhanced the ECL stability and intensity. Integrating with CRISPR/Cas12a system, the Au NCs@g-C 3 N 4 behaved as sensing substrate to construct a “off-on” switch-type ECL sensor for AFB1 detection based on ECL resonance energy transfer (ECL-RET). The presence of targets AFB1 can specifically bind its aptamer to trigger the release of the activator. Using dual aptamer-regulated activation of CRISPR-Cas12a, AFB1 can be quantified via the ECL sensor, displaying a wide detection range from 0.2 pg/mL-100 ng/mL and a detection limit of 0.08 pg/mL. Furthermore, good practicability was verified in real samples assay, providing an efficient tool for the early warning of AFB1 pollution.