摘要
ATT-AuNCs provide intrinsically efficient solid-state AIE emission without additional material engineering. • CRISPR/Cas12a enables efficient target-triggered molecular signal amplification. • The biosensor achieves a 0.37 pg·mL −1 detection limit for NDMA in processed meat samples. N -Nitrosodimethylamine (NDMA) is a potent carcinogenic small-molecule contaminant, and its trace-level occurrence necessitates sensitive and reliable detection methods. Herein, we developed an electrochemiluminescence (ECL) aptasensor integrating a solid-state aggregation-induced emission (AIE)-active gold nanocluster (Au NCs) luminophore with clustered regularly interspaced short palindromic repeats (CRISPR)/Cas12a-mediated molecular signal amplification for ultrasensitive NDMA detection. 6-Aza-2-thiothymine (ATT)-protected Au NCs (ATT-AuNCs) served as the ECL luminophore with triethylamine as the coreactant, while ferrocene (Fc)-labeled single-stranded DNA (Fc-ssDNA) acted as the ECL quencher. Upon NDMA recognition, target-induced strand displacement released a DNA activator, which activated the Cas12a/crRNA complex and triggered trans-cleavage of electrode-bound Fc-ssDNA. Cleavage of the ssDNA backbone disrupted the linkage between the Fc moiety and the electrode-anchored terminus, allowing Fc-containing cleavage products to detach from the electrode interface and thereby reducing Fc-mediated quenching. As a result, the ECL emission of ATT-AuNCs was restored, translating target recognition into an enhanced ECL response. The proposed sensor exhibited a linear range of 5 pg·mL −1 to 500 ng·mL −1 with a detection limit of 0.37 pg·mL −1 . By exploiting the intrinsically efficient solid-state AIE emission of ATT-AuNCs and CRISPR/Cas12a-mediated signal amplification, this strategy enables ultrasensitive NDMA detection. Download: Download high-res image (118KB) Download: Download full-size image
危险品化学品经营许可证（带存储）