A CRISPR-Cas12a Based Lateral Flow Biosensor For The Sensitive And Specific Detection Of African Swine-fever Viruses

African swine fever(ASF)is caused by African swine fever virus(ASFV)that infects the domestic pigs,wild pigs(such as African wild pigs or European wild pigs,etc.).It is an acute,hemorrhagic,virulent infectious disease that endangered the global pig industry is seriously,indirectly affecting food safety.At present,there is no effective vaccine to prevent and control ASFV.Early and rapid diagnosis and prevention of ASFV is the main means to prevent the outbreak of ASFV.In this study,we developed a rapid detection method for African swine fever virus based on CRISPR/Cas12a system,polymerase chain reaction amplification and colloidal gold strip technology.We analyzed the specificity and sensitivity,and confirmed that the nano gold strip detection method based on CRISPR/Cas12a has strong specificity,high sensitivity,and it is easy to use.This method is applicable for the detection of a wide range of pathogens.The development of colloidal gold strip technology can effectively detect food safety problems caused by foodborne pathogens and ensure food safety.To establish the lateral flow strip assay,the CRISPR/Cas g RNA and cr RNA are designed,which is specific to the gene VP73 of the African swine fever virus.I also designed and optimized the length and concentration of the reporter of CRISPR/Cas cleavage system.The capture probe fixed on the test zone of the strip was complementary to the reporter,which captures the uncleared reporter sequence.The absence of the test line indicates positive results as a result of the cleavage of the reporter.This method is simple to operate and highly specific with a detection limit of2.5×10^-15M,which is conducive to the early diagnosis of AFSV and the effective control of the outbreak,ensuring food safety.