LB (Amp/Kan) plate

  1. Dissolve 32 g of LB agar powder in 800 mL of sterile/ELGA water. (4g of LB agar powder in 100 mL)

  2. Autocleave it for 20 min at 121C.

  3. Cool it to about 45-50C by letting it sit on a bench (room temperature).

Tip

If you can keep touching it with bare hands, that indicates the temperature of the LB is around 45-50C and it’s time to add antibiotics.

  1. Add 800 uL of 1000x antibiotics to the autocleaved LB agar-water.

  2. Dissolve the antibiotics by stirring with a stirrer.

  3. Pour 30-35ml of the antibiotics-containing LB per a petri dish.

Tip

You can use a pipette but the LB can easily become solid so pouring LB by hand might be a good alternative method.

  1. Incubate the plate at RT until the LB agar become solid (normally it takes about 30-45min).

  2. After the LB agar become solid, put the plates back to a bag and store it at 4C.