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1. Pick a colony with a sterile toothpick or use 30µl of a liquid culture and inoculate 3.0ml of LB + 3ul AMP stock (75 mg/ml) in a sterile culture tube.
2. Let grow at 37^oC overnight, shaking vigorously.
3. Centrifuge 1.5ml of liquid culture for 10 sec at room temperature in a sterile 1.5 ml tube. Never use all of the liquid culture if this is a new clone. Store the excess at 4^oC for future use.
4. Remove all but ~60ul of supernatant and vortex well to re-suspend.
   DO STEPS 5 &6 AS quickly AS POSSIBLE. If doing more than 5-6 samples at one time, keep on ice.
5. Add 300ul TENS buffer and vortex 2-5 seconds or until sticky. (Keep samples on ice)
6. Add 150ul of 3M sodium acetate (pH 5.2) and vortex 2-5 seconds.
7. Immediately centrifuge at room temperature, 14,000 RPM for 10 minutes.
8. Transfer supernatant to a clean tube.
9. Add 1/2 volume of phenol and 1/2 volume of chloroform, vortex and centrifuge for 5 minutes at room temperature. Transfer the aqueous layer (top) to a new tube and discard the bottom layer (organic).
10. Repeat Step 9 one or two more times.
11. Add 1 volume of chloroform to aqueous layer, vortex, and centrifuge as above. Remove top layer as above.
12. Add 900ul of cold 100% EtOH and store at -20^oC for 8 hours to overnight or at -80^oC for 15 minutes (-80^oC method tends to cause a decrease in yield).
13. Centrifuge at 14,000 RPM at 4^oC for 15 minutes.
14. Remove supernatant and add 200-500ul of cold 70% EtOH.
15. Centrifuge as above for 2 minutes.
16. CAREFULLY remove supernatant (pop spin if necessary) and let pellet air dry.
17. Re-suspend pellet in sterile nH2O; use 25-50 µl, depending on the size of the pellet.
18. Check quantity and quality of plasmid DNA on a gel (run 1-2 µl).

Digestion of Plasmid DNA