LB plates

This recipe is for 500 mL of LB agar. This makes about 20-25 plates (1 sleeve).

Materials

 * 5 g Bacto Tryptone


 * 2.5 g Yeast Extract


 * 5 g NaCl


 * 7.5 g Bacto Agar

Method

 * 1) Add solids and 500 mL of deionized water to a large flask. Note the Bacto   Agar will not dissolve until melted in the autoclave; but all other ingredients will dissolve. 
 * 2) Autoclave using the LIQUID cycle.
 * 3) Allow flask to cool on bench or in water bath. Do not allow the solution to cool completely as it will start solidifying in the flask.
 * 4) To check if it is time to add the antibiotic, give the medium some time to cool and then hold the flask in your hands. If you can hold the flask for a good few seconds, then the temperature is around ~50-55 °C. At this  temperature, you can add the antibiotics . See table below for antibiotic concentrations.  Do not touch or hold the flask right after autoclaving as it may cause burns.
 * 5) Mix well by stirring for 5 minutes.
 * 6) Prepare plates by pouring medium into plates (20-25 mL per plate). If bubbles form on the surface of the medium, quickly use a flame from a burner to pop them. Do not flame medium for more than a few seconds as it will degrade the antibiotics.
 * 7) Place the plates on becnh top and allow to cool at room temperature overnight.
 * 8) After the plates have cooled, place them in the sleeve and mark them accordingly. Then seal the sleeve and store at  4 °C.