Integrating PCR-free amplification and synergistic sensing for ultrasensitive and rapid CRISPR/Cas12a-based SARS-CoV-2 antigen detection [article]

Xiangxiang Zhao, Zhengduo Wang, Bowen Yang, Zilong Li, Yaojun Tong, Yuhai Bi, Zhenghong Li, Xuekui Xia, Xiangyin Chen, Weishan Wang, Gao-Yi Tan, Lixin Zhang
2021 medRxiv   pre-print
Antigen detection provides particularly valuable information for medical diagnoses; however, the current detection methods are less sensitive and accurate than nucleic acid analysis. The combination of CRISPR/Cas12a and aptamers provides a new detection paradigm, but sensitive sensing and stable amplification in antigen detection remain challenging. Here, we present a PCR-free multiple trigger dsDNA tandem-based signal amplification strategy and a de novo designed dual aptamer synergistic
more » ... g strategy. Integration of these two strategies endowed the CRISPR/Cas12a and aptamer-based method with ultra-sensitive, fast, and stable antigen detection. In a demonstration of this method, the limit of detection was at the single virus level (0.17 fM, approximately two copies/μL) in SARS-CoV-2 antigen nucleocapsid protein analysis of saliva or serum samples. The entire procedure required only 20 minutes. Given our system's simplicity and modular setup, we believe that it could be adapted reasonably easily for general applications in CRISPR/Cas12a-aptamer-based detection.
doi:10.1101/2021.06.17.21258275 fatcat:isl4k5uhevhxnbw52tlqast5eq