This kit is suitable for extracting plasmid from 150-300 mL of the bacterial solution cultured overnight , using an improved SDS-alkaline lysis method to lyse the bacteria. The crude extract is selectively combined with a unique Endotoxin Scavenger and separated by centrifugation to remove endotoxins. Then, teh silicon matrix membrane in the centrifugal adsorption colun selectively binds to plasmid DNA in the solution under conditions of high salt and low pH.  This is followed by addition of wash buffer to  remove impurities and other becterial components. Finally, a low-salt, high-pH elution buffer is used to elute pure plasmid DNA from the silicon matrix membrane. The silicon matrix membrane in centrifugal adsorption column employs imported special adsorption membrane, and the adsorption amount difference between the column and the column is very small and the repeatability is well. Phneol, chloroform and other toxic reagents are not required, and neither is ethanol required for precipitation. This kit can be used to rapidly extract 0.2-1.5 mg of pure high-copy plasmid DNA, with an extraction rate of 80% - 90%. The unique process formula removes endotoxin, the content of endotoxin is extremely low and the cell transfection effect is excellent. The extracted plasmid could be directly used in enzymatic digestion, PCR, in vitro transcription, transformation, sequencing and other molecular biology experiments.