Team:University College London/Protocols/Miniprep1

Miniprep Protocol 1 - Qiagen

Step 1 - Pellet Cells: Pellet 1-5ml bacterial overnight culture by centrifugation at >8000rpm (68800 x g) for 3 min at room temperature (15-25oC)

Step 2 - Resuspend Cells: Resuspend pelleted bacterial cells in 250ul Buffer P1 and transfer to a microcentrifuge tube

Step 3 - Puncturing Cell Membrane: Add 250ul Buffer P2 and mix thoroughly by inverting the tube 4-6 times until the solution becomes clear. Do not allow the lysis reaction to proceed for more than 5 min.

Step 4 - Neutralising buffer P2: Add 350ul Buffer N3 and mix immediately and thoroughly by inverting the tube 4-6 times.

Step 5 - Centrifuge:

RPM: 13000

Time:10 minutes

Temperature: 18oC

Step 6 - Centrifuge: Apply the supernatant from step 5 to the QIAprep spin column by decanting or pipetting. Centrifuge for 30-60s and discard the flow-through.

Step 7 - Remove Endonucleases from Sample: Wash the QIAprep spin column by adding 500ul of Buffer PB. Centrifuge for 30-60s and discard flow-through.

Step 8 - Remove salts from sample: Wash the QIAprep spin column by adding 750ul of Buffer PE. Centrifuge for 3-60s and discard flow through.

Step 9 - Centrifuge:

RPM: 13000

Time:1 minute

Temperature: 18oC

Step 10 - Elute DNA: Place the QIAprep column in a clean 1.5ml microcentrifuge tube. To elute DNA, add 50ul Buffer EB to the centre of the spin column, let it stand for 1 min, and centrifuge for 1 min.