In this kit. the plasmid DNA was purified rapidly by the modified SDS alkaline lysis combined with the method of selective adsorption of DNA on DNA preparation membrane. It applies to extract up to 20ug of high purity plasmid DNA from 1-5 ml bacterial culture. It has been used in molecular biology experiments such as sequencing. in vitro transcription and translation. restriction endonuclease digestion and bacterial transformation.