Preparation method of multipurpose RNA target molecule

The invention discloses a preparation method of an RNA (Ribonucleic Acid) target molecule. The preparation method comprises the following steps: (1) selecting a DNA (Deoxyribose Nucleic Acid) target fragment of an RNA virus to be detected; designing promoter sequences and primers of T7 and T3; (2) adding a T7 promoter sequence to the 5'end of the positive chain of the target fragment, and adding a T3 promoter sequence or a T7 promoter sequence to the 5 'end of the negative chain of the target fragment; (3) artificially synthesizing the DNA fragment containing the promoter sequence, and carrying out PCR (Polymerase Chain Reaction) amplification by taking the DNA fragment as a template and utilizing a primer sequence of a T7 promoter and/or a T3 promoter to obtain a large number of double-stranded DNA molecules; and (4) carrying out transcription amplification by using T7 RNA polymerase and/or T3 RNA polymerase by taking the DNA product obtained in the step (1) as a template to obtain a single-chain or double-c