The application discloses a preparation method of
DNA molecular weight standards based on self-
assembly, comprising the following steps: S1, two single-stranded DNAs with equal length but not complete complementarity are chemically synthesized, and each single-stranded
DNA is composed of two sequences, one of which is a complementary sequence, and the other is a self-
assembly complementary sequence; S2, directional self-
assembly is carried out in a reaction
buffer solution, and a ligase is added; S3, reaction is carried out at
room temperature for 0.5-10 min, the number of self-assembly is controlled by controlling the reaction time, the number of bases added by each connection is equal to the number of bases of the single-stranded
DNA, and a plurality of DNA molecular weight standards with arithmetic progression of sequence length are formed; S4,
heat inactivation treatment is carried out; S5, an
electrophoresis loading
buffer solution is added, and the DNA molecular weight standards are prepared, and the DNA molecular weight standards are stored at low temperature. The application has the advantages of simple process, low manufacturing cost, strong expandability and the like, and has a good application prospect.