Zymo Research Plasmid Minipreps
Zymo Research Zippy Plasmid Minipreps
Zymo Research: http://www.zymoresearch.com/
Cat. D4036, D4037
The kit suggests starting with 600 ul of overnight bacterial culture. We tested the capacity of the kit and increased that volume to 8 ml.
If the minipreps are for screening to find a new clone, we reserve 700 ul in a sterile 1.5 ml tube for use in making a glycerol stock.
We spin down the 8 ml culture in a clinical centrifuge at 4000 rpm for 6 minutes. We dump the supernatant and resuspend the pellet in either 600 ul sterile water or 600 ul sterile LB broth.
Step 9 is to spin down the Zippy Wash Buffer for 30 seconds, then dump the wash buffer from the collection tube. We follow that step with a second spin of 30 seconds to make sure that the column is dry and no wash buffer carries over to the elution step.
For elution, we use 30 ul of Zippy Elution Buffer, let stand for 1 minute on the bench, and spin for 30 seconds as suggested. However, we often reapply the elution buffer to the column, let stand for another minute, then spin for 1 minute. This improves the plasmid yield substantially.
We use a Nanodrop to measure the concentration and purity of the plasmid solution. It is important to blank the Nanodrop with the same solution (same bottle) of Zippy Elution Buffer that was used to elute.
Yield is dramatically affected by the copy number of the plasmid vector used.