State Key Laboratory of Oncogenes and Related Genes, Institute for Personalized Medicine, School of Biomedical Engineering, Shanghai Jiao Tong University, Shanghai, 200030, China.
Shanghai Synchrotron Radiation Facility, Zhangjiang Lab, Shanghai Advanced Research Institute, Chinese Academy of Sciences, Shanghai, 201210, China.
Small Methods. 2021 Dec;5(12):e2100935. doi: 10.1002/smtd.202100935. Epub 2021 Oct 10.
Nucleic acid analysis using ultrasensitive and simple methods is critically important for the early-stage diagnosis and treatment of diseases. The CRISPR/Cas proteins, guided by a single-stranded RNA have shown incredible capability for sequence-specific targeting and detection. Herein, in order to improve and expand the application of CRISPR/Cas technology to the electrochemical interface-based nucleic acids analysis, the authors develop a CRISPR/Cas12a powered DNA framework-supported electrochemical biosensing platform via the cis and trans cleavage of Cas12a on the heterogeneous carbon interface (the existing publications which commonly adopted trans-cleavage). Their solid-liquid interface is first immobilized by 3D tetrahedral framework nucleic acids (FNAs) with specific DNA recognition probe. Based on the recognition of the complementary target through protospacer adjacent motif (PAM) confirmation and CRISPR-derived RNA (crRNA) matching, the easily formed Cas12a/crRNA duplex can get access to the interface, and the cis and trans cleavage of Cas12a can be easily activated. In combination with the enzyme catalyzed reaction, they achieved an ultralow limit of detection (LOD) of 100 fm in HPV-16 detection without pre-amplification. Furthermore, the platform is compatible with a spike-in human serum sample and has superior stability. Thus, their reported platform offers a practical, versatile, and amplification-free toolbox for ultrasensitive nucleic acid analysis.
利用超灵敏和简单的方法进行核酸分析对于疾病的早期诊断和治疗至关重要。CRISPR/Cas 蛋白在单链 RNA 的指导下,具有针对特定序列的靶向和检测的惊人能力。在此,为了提高和扩展 CRISPR/Cas 技术在基于电化学界面的核酸分析中的应用,作者通过 Cas12a 在异质碳界面上的顺式和反式切割(现有文献中通常采用反式切割),开发了一种 CRISPR/Cas12a 驱动的 DNA 框架支持的电化学生物传感平台。他们的固液界面首先通过具有特定 DNA 识别探针的三维四面体框架核酸 (FNA) 固定。基于通过前间隔基邻近基序 (PAM) 确认和 CRISPR 衍生 RNA (crRNA) 匹配对互补靶标的识别,易于形成的 Cas12a/crRNA 双链体可以进入界面,并且 Cas12a 的顺式和反式切割可以很容易地被激活。结合酶催化反应,他们在无需预扩增的情况下,在 HPV-16 检测中实现了 100fm 的超低检测限 (LOD)。此外,该平台与掺入的人血清样本兼容,具有优异的稳定性。因此,他们报告的平台为超灵敏核酸分析提供了一种实用、多功能且无需扩增的工具包。