Aseptic techniques – in practice
- Complete the procedure with a Bunsen burner on the bench to kill airborne microorganisms.
- Pass a metal loop through the flame to sterilise it.
- Allow the metal loop to cool to prevent any microorganism it touches being killed.
- Remove the In microbiology, a colony of microbes, typically on an agar plate. bottle lid and sweep the neck of the bottle through the flame to sterilise it.
- Glide the metal loop through the bacterial culture. This will To introduce bacterial cells. the metal loop with bacteria.
- Sweep the neck of the bottle through the flame to sterilise it again.
- Replace the culture bottle lid to prevent contamination.
- Partially lift the A clear glass or plastic dish, used to grow living cells from organisms so they can be studied. lid to prevent the entry of unwanted airborne microorganisms.
- Gently glide the inoculated metal loop over the surface of the nutrient agar (agar enriched with nutrients and minerals essential for bacterial growth). This is known as plating.
- Pass the metal loop through the flame again to sterilise it.
- Tape the Petri dish lid on.
- Incubate at 25°C – below body temperature to ensure pathogenic microorganisms do not grow. Incubate upside down to avoid condensation dripping on the bacteria.