QIAGEN Plasmid Mini Kit (100)

The QIAGEN Plasmid Mini Kit uses gravity-flow, anion-exchange tips for purification of transfection-grade plasmid DNA, with lysate clearing and isopropanol precipitation achieved by centrifugation. The unique anion-exchange resin in the tips is developed exclusively for nucleic-acid purification, delivering DNA purity equivalent or superior to that obtained by two successive rounds of CsCl gradient centrifugation, while avoiding toxic substances such as phenol, chloroform, ethidium bromide, and CsCl.

Designed for a culture volume of 3–10 ml and 1 sample per run, the kit handles high-copy, low-copy, and cosmid DNA. The manual gravity-flow workflow is completed in 80 min, with up to 20 µg of plasmid DNA recovered for use in transfection, cloning, sequencing, and capillary sequencing applications. Prepacked tips operate by gravity flow and never run dry, minimizing hands-on time.

The Quick-Start protocol specifies resuspending the bacterial pellet in 0.3 ml Buffer P1, lysing with 0.3 ml Buffer P2, neutralizing with 0.3 ml prechilled Buffer P3 on ice for 5 min, and clearing the lysate by centrifugation at 14,000–18,000 x g for 10 min at 4°C. A QIAGEN-tip 20 is equilibrated with 1 ml Buffer QBT, the cleared lysate is loaded, washed with 2 x 2 ml Buffer QC, and DNA is eluted with 0.8 ml Buffer QF. DNA is precipitated with 0.56 ml (0.7 volumes) room-temperature isopropanol and the pellet washed with 1 ml room-temperature 70% ethanol. Reagents can be stored at room temperature (15–25°C) for up to 2 years; RNase A solution is added to Buffer P1 and stored at 2–8°C.