Dual-functional DNAzyme powered CRISPR-Cas12a sensor for ultrasensitive and high-throughput detection of Pb2+ in freshwater

DNAzyme-activated CRISPR/Cas assay for sensitive and one-pot detection of lead contamination

“…[18][19][20] Harnessing the exceptional catalytic efficiency, the CRISPR/Cas12a system promises to increase the sensitivity of DNAzyme-based assays. DNAzyme-CRISPR tandem assays, while promising in bypassing nucleic acid amplification, 4,21 often encounter challenges due to the necessity of a separation step, [22][23][24] making the assays incapable of homogeneous reaction in one tube and less ideal for on-site detection.…”

“…Besides, the assays combining Cas12a with DNAzyme cannot achieve a one-tube homogeneous reaction, and generally require a separation step based on additional auxiliary tools such as magnetic beads and gold nanoparticles (Table S2, ESI †). 22,[24][25][26] The Klenow-mediated extension, serving as a bridge between the DNAzyme recognition and the Cas12a reporting, renders the separation step unnecessary and enables one-pot detection. Furthermore, in comparison to previously reported DNAzyme-based methods (Table S2, ESI †), 27,28 the DzCas12T assay demonstrates superior performance, characterized by its higher sensitivity.…”