摘要
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 sensing 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 min.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.
基金
This work was supported by the National Key R&D program of China(2020YFA0907800)
the National Natural Science Foundation of China(31922002,31720103901,31772242 and 31870040),the 111 Project(B18022)
the Fundamental Research Funds for the Central Universities[22221818014]
the Youth Innovation Promotion Association CAS(Y202027)to W.W and the Open Project Funding of the State Key Laboratory of Bioreactor Engineering.
