Preparing LB Media in Different Water Types

Yesterday it occurred to me that I couldn’t autoclave LB media made with DDW or D2O because of D-exchange. So I had to come up with a solution which prompted me to ask the world (thank you internet). Through the power of open science (victory for ONS!) I was able to get some comments that said I should use a 0.2 micron filter:

Well that is what I did and here is my protocol:

  •  I have this easy mix stuff that dissolves pretty rapidly (see Experiments’ Products Page), and it requires 20g/L
  • I want to make 100ml amounts for each water type (99% DDW and 99% D2O), so I need 2g of LB media.
  • Add 2 g to the 100ml of water and stir.
  • Suck up in a sterile syringe.
  • Add 0.2 micron filter to syringe and pump into autoclaved glassware.

Presto!