ASEPTIC TECHNIQUE

Aseptic technique is the set of habits that keep unwanted microbes out of your samples, media and equipment, and keep your cultures from contaminating you or the lab. Every other protocol on this site depends on it.

WHAT YOU NEED?

• 70% ethanol and paper towels

• Bunsen burner or a biosafety cabinet / fume hood

• Sterile loops, tips and pipettes

• Lab coat and gloves

• Biohazard waste container

STEPS

1. Tie back hair, put on a lab coat and gloves, and remove anything you don’t need from the bench.

2. Wipe the work surface with 70% ethanol and let it dry.

3. Light the Bunsen burner or switch on the hood to create a clean working zone.

4. Label all plates and tubes before you start.

5. Open containers only for as long as needed, and hold lids facing down, never placing them open-side up on the bench.

6. Flame the necks of bottles and tubes briefly when opening and closing them. This is not needed in the fume hood.

7. Use a new sterile loop, tip or pipette for every sample.

8. Dispose of used materials in biohazard waste and wipe the bench with ethanol again when finished.

TIPS

• Keep ethanol well away from the flame.

• Never place open fire like Bunsen burners in a hood.

• Work calmly and avoid talking or reaching over open plates.

• Include a negative control (an uninoculated tube or plate) so you can catch contamination.