Sensitive and Amplification-Free Electrochemiluminescence Biosensor for HPV-16 Detection Based on CRISPR/Cas12a and DNA Tetrahedron Nanostructures

Rapidand accurate detection of biomarkers was very important forearly screening and treatment of diseases. Herein, a sensitive andamplification-free electrochemiluminescence (ECL) biosensor basedon CRISPR/Cas12a and DNA tetrahedron nanostructures (TDNs) was constructed.Briefly, 3D TDN was self-assembled on the Au nanoparticle-depositedglassy carbon electrode surface to construct the biosensing interface.The presence of the target would activate the trans-cleavage activityof Cas12a-crRNA duplex to cleave the single-stranded DNA signal probeon the vertex of TDN, causing the Ru(bpy)(3) (2+) to fall from the electrode surface and weakened the ECL signal.Thus, the CRISPR/Cas12a system transduced the change of target concentrationinto an ECL signal enabling the detection of HPV-16. The specificrecognition of CRISPR/Cas12a to HPV-16 made the biosensor have goodselectivity, while the TDN-modified sensing interface could reducethe cleaving steric resistance and improve the cleaving performanceof CRISPR/Cas12a. In addition, the pretreated biosensor could completesample detection within 100 min with a detection limit of 8.86 fM,indicating that the developed biosensor possesses the potential applicationprospect for fast and sensitive nucleic acid detection.

Automated summary

Rapid and accurate detection of biomarkers is crucial for early screening and treatment of diseases. This study developed a sensitive and amplification-free electrochemiluminescence (ECL) biosensor based on CRISPR/Cas12a and DNA tetrahedron nanostructures (TDNs). The CRISPR/Cas12a system transduced the change of target concentration into an ECL signal enabling the detection of HPV-16.