Preparation method of nCOVsiRNA drug for targeted delivery of shRNA by RBD

The invention relates to a preparation method of an nCOVsiRNA drug for targeted delivery of shRNA by using RBD, and discovers a novel targeted delivery vector RBD derived from a coronavirus receptor binding domain and an anti-variant strain target shRNA derived from a coronavirus conserved gene. According to the present invention, shRNA and RBD are synthesized, the positive sense strand and the negative sense strand of the shRNA are respectively connected with the N end of the RBD, such that the compound having the gene drug and macromolecular vaccine dual effects and using the RBD to deliver the shRNA in the targeting manner is formed, and the RBD and the shRNA are subjected to mutual synergy so as to produce a plurality of new functions; wherein the shRNA is not only a broad-spectrum antiviral drug, but also an immunologic adjuvant for enhancing the effect of the RBD vaccine; the RBD not only can be used as a targeted delivery carrier to avoid side effects of non-targeted gene therapy, but also is a common