A modularized universal strategy by integrating CRISPR/Cas with nanoporous materials for ultrasensitive determination of nucleic acids

Nucleic acid detection is crucial for early disease diagnosis and related clinical applications. Exploring nucleic acid amplification-free yet highly sensitive detection strategies is of significance for the development of accurate and user-friendly point-of-care testing devices. Herein, a modularized universal electrochemical sensing strategy was proposed based on the synergistic effect of CRISPR/Cas12 system and nanoporous materials. The trans -cleavage activity of Cas12a, which was activated by HPV-16 target, was utilized to cut the gatekeepers of mesoporous silica nanoparticle nanocontainers. The released methylene blue was entrapped by a mercaptobenzoic acid functionalized nanoporous gold (NPG) sensing platform. By virtue of the excellent electrocatalytic ability of NPG, ultrasensitive detection of HPV-16 was achieved over a broad linear range of 7 orders of magnitude with a detection limit as low as 0.41 fM. Moreover, determination of HPV-18 was easily achieved by only altering crRNA, revealing the remarkable universality of this strategy and its superiority of modularized design. The practical applicability of the proposed sensing strategy was verified in terms of specificity, stability, and complex biological sample analysis, demonstrating its promising prospects in the development of reliable, universal, robust, and user-friendly point-of-care diagnostic devices.