The High-Speed Plasmid Miniprep Kit was designed for plasmid DNA purification or cosmid DNA purification from 1-4 ml of cultured bacterial cells. Modified Alkaline Lysis method and RNase treatment are used to obtain clear cell lysate with minimal genomic DNA/RNA contaminants. In the presence of chaotropic salt, plasmid DNA in the lysate binds to the glass fiber matrix of the spin column. Contaminants are removed with a Wash Buffer (containing ethanol) and the purified plasmid DNA is eluted by a low salt Elution Buffer or TE. Typical yields are 20-30 μg for high-copy number plasmid or 3-10 μg for low-copy number plasmid from 4 ml of cultured bacterial cells. DNA phenol extraction or alcohol precipitation is not required and the entire procedure can be completed within 30 minutes.