This procedure is to concentrate minipreps by combining a number of them into a smaller volume.
1. Add NaCl to miniprep sample in an amount so that the final concentration of NaCl (after the addition of ethanol) will be 0.2M. Mix by inverting.
2. Add 90% ethanol in an amount that is twice the volume of the miniprep sample (eg. if miniprep volume is 30 uL, add 60 uL of ethanol).
3. Incubate tube at -80 C for an hour.
4. Centrifuge tube for 15 min at 4 C. The centrifuge for this step is found in Jay's lab on the 7th floor.
5. Pipet out supernatant, being careful not to touch the sides of the tube, as the pellet may be very small, or not visible at all. Allow to air-dry for a few minutes.
6. Resuspend DNA pellet in Buffer EB. The amount here is at your discretion, and will determine how concentrated your precipitated sample will be.