Aseptic
technique
for
plating bacteria
Before you
begin, think
about what you need to do and make sure everything is labeled
Work quickly,
but
carefully
Work near
your Bunsen
burner, it will reduce airborne contamination.
Procedure
1.
Put on
gloves, briefly
rub ethanol on your gloved hands.
2.
Spray
area with
ethanol, wipe off with a paper towel if necessary.
3.
Light
Bunsen burner.
4.
Using
your non-dominant
hand, hold your tube and open it with your dominant hand. If the tube
has a
screwtop lid, put the lid of the tube into your non-dominant hand.
5.
Remove
plate lid with
your free hand and set it upside down near your plate.
6.
Use your
pipette to
pick up the appropriate volume of culture, then dispense into the
center of the
plate.
7.
Close
your culture tube
and place in rack. Cover your plate with the lid.
8.
Using
ethanol,
sterilize your spreader by passing it BRIEFLY through the flame of your
burner
to ignite it. Do not hold the spreader over the burner.
9.
Let the
ethanol burn
off your spreader, then allow the spreader to cool for 30 seconds. Do
not set
it down or touch anything with it.
10.
Once
spreader has cooled, open your plate, holding
the lid with your non-dominant hand. Use the same hand to hold the
plate steady
by grabbing the edge of the plate.
11.
Holding
the spreader in your dominant hand, use a
circular motion to spread the culture evenly across the plate.
12.
Cover the
plate and return the spreader to the
ethanol. Repeat steps 4-11 for each sample.
Materials
necessary
LB
Plates (with antibiotics and inducers, if necessary)
Pipette
tips
Bacterial
cultures
Ethanol
Equipment
necessary
Spreader
Micropipette
Bunsen
burner