Cell culture tips

As my postdoc / mentor likes to say,

Trust no one. (only applies to cell culture, not to life in general)

A week after my first attempt at passaging cells, I came back to them and found them contaminated, so I wrote this to remind myself of some tips to help maintain a sterile environment.

Tips

• Before each use
  • Make sure sash is at the correct height
  • Wipe down hood thoroughly with 70% ethanol before starting and after each use
• Sterile handling
  • Spray down everything that goes into the hood with 70% ethanol, including
    • First time putting your hands and arms into the hood: spray your gloved hands + a little bit up your sleeve
    • Every time your hands exit the hood, spray them with 70% ethanol again before putting them back into the hood
  • Switch Pasteur pipette tips at at least between different cell types
  • Apparently a controversial statement, but keep lids and caps facing up
  • Avoid sucking up media into serological pipette gun
  • Keep lids and caps on as often as possible
  • Try your best to not touch the inside of dishes and flasks with pipettes and tips
• Organization
  • Keep objects out of the vent at the front of the hood (push things inside the hood)
  • Try not to pass hands, bottles, pipettes, tubes etc. over any open and uncovered media bottles, uncovered plates, and opened tips
• After each use
  • UV
  • Wipe everything down with 70% ethanol
  • Vacuum tube: spray with bleach + 70% ethanol