LB Agar Plates
Weigh out the following into a 1L Erlenmeyer flask : 5g NaCl 5g Tryptone 2.5g Yeast .
Extract 7.5g Agar add ( dH2O ) to 500mL .
Swirl to mix .
Cover the top of the flask with aluminum foil and label with autoclave tape .
Autoclave on the liquid setting for 20 minutes or according to your autoclave's specifications .
After removing the solution from the autoclave , allow the agar solution to cool to 55°C .
Add the appropriate amount of desired antibiotic to the solution ( 500μL if you are using a 1,000x antibiotic stock ) and swirl to mix .
Pour ~ 20mL of LB agar per 10cm polystyrene Petri dish .
Place the lids on the plates and allow them to cool for 30 - 60 minutes ( until solidified ) .
Invert the plates and let sit for several more hours or overnight .
Label the bottom of plates with antibiotic and date and store in plastic bags or sealed with parafilm at 4°C .
