Making LB Plates

LB Agar (To Make 1L):

  • Before you start:
    • Use AGAR not agarose!
    • Use an Erlenmeyer flask that is twice the volume of your solution (avoid spillage in autoclave).
    • Keep your flask on a stir plate with a stir rod.
    • Put Aluminum foil on the top of the flask and put autoclave tape on.
    • DON`T let it solidify after autoclaving by keeping it on a stir plate while it cools.
    • DON`T put tubes of antibiotics back into freezer.
  • Add the following to 800 ml MilliQ H20:
Bacto-tryptone || 10g
Yeast extract || 5g
NaCl || 10g
  • Adjust pH to 7.5 with NaOH (Optional).
  • Add 15g agar.
  • Melt agar into solution in the microwave (Optional).
  • Adjust volume to 1L with MilliQ H20
  • Autoclave on the liquid cycle (no drying time) (aka LIQ20) for 30 minutes.
  • Wait for it to cool to touchable temperature and then add antibiotics if necessary. Amount of antibiotic required should be in the protocol binder.
  • Pour plates, making sure they are color coded with the type of antibiotic that you used.

Making LB Broth:

  • All of the above WITHOUT AGAR.