Signal-enhanced visual strand exchange amplification detection of African swine fever virus by the introduction of multimeric G-quadruplex/hemin DNAzyme

African swine fever virus (ASFV) causes hemorrhagic infectious disease in pigs with a fatality rate of nearly 100%. In this study, we developed a visual strand exchange amplification detection assay for ASFV. In the presence of ASFV, DNA amplification products containing multimeric G-quadruplex sequences were amplified by strand exchange amplification. These G-quadruplexes, assembled with hemin to form DNAzyme, displayed enhanced significant turned-on colorimetric signals to indicate detection results. The results showed that dimeric DNAzyme had the best visualization effect. Under the optimal reaction parameters, there was a linear relationship between the absorbance of the reaction solution at 417 nm and the logarithm of ASFV concentration ranged from 1 x 10(1) to 1 x 10(3) copies/mu L, and the detection limit was 2.7 copies/mu L. We hoped this visual assay could be helpful in the rapid and sensitive detection of ASFV, and the results of multimeric G-quadruplex/hemin DNAzyme could be helpful for the development of better visual detection assays.

Automated summary

In this study, a visual strand exchange amplification detection assay was developed for the detection of African swine fever virus (ASFV). The assay showed rapid and sensitive detection of ASFV through amplification of specific DNA sequences and colorimetric signals. The results of this study could be helpful for the development of better visual detection assays.