Final answer:
When attaching the tip to a pipette, maintaining sterility is crucial, which includes preventing contact with non-sterile surfaces and using aseptic techniques during liquid transfer.
Step-by-step explanation:
When attaching the tip to the pipette, it is key to ensure that both the pipette and the media remain sterile. This means that there should be no direct contact with your hands, skin, or lab surfaces. To maintain sterility:
- Always make sure that the instrument is level and that your eye is at the level of the top of the liquid when reading it.
- Hold tubes or bottles at an angle during the transfer process to minimize contamination by airborne contaminants.
- Briefly pass the opening of the tube or bottle through a flame before and after the transfer process to discourage the presence of any airborne contaminants.
It is also important to be comfortable with the use of the pipette and pipump. Practice with water first by drawing up and releasing liquid in measured increments. Once proficient, apply these techniques using aseptic methods with media in a sterile environment.