Petri Dish Handling Checklist: 10 Things Pros Never Forget
Whether you're culturing bacteria, working with stem cells, or imaging live cells or embryos, attention to detail with Petri dishes can make or break your results. Use this quick checklist to avoid common mistakes and maintain best practices in the lab.
Use Sterile Tools & Aseptic Technique
- Disinfect tools you will use with the cell culture dishes and wash your hands before donning gloves
- Work in a laminar flow hood
- Store and handle media properly
Label the Bottom of the Dish
- Label the base (not the lid) with the sample name, date, and your initials
- Use a waterproof marker or printed labels
- Place the label along the edge for visibility under a microscope
Let Agar Cool Before Pouring
- Cool agar to 45–50°C to avoid condensation or media damage
- Pour agar slowly to reduce bubbles
- Allow the agar to setup on a level surface
Store Dishes Inverted
- Store cell culture dishes with the agar-side up to prevent condensation drip
- Stack culture plates evenly and store them in clean conditions
Avoid Overcrowding the Plate
- When populating the culture, use a proper streaking technique
- Only place one (or few) sample(s) per cell culture dish to allow clear separation
Minimize Plate Exposure
- If necessary, only remove the Petri dish lid for brief periods
- Keep hands and sleeves away from open dishes
- Handle plates only under sterile conditions
Incubate with Precision
- Set the incubator temperature according to protocol
- Do not over-incubate your cell culture dishes
- Calibrate your incubator temperature regularly
Never Touch the Agar
- Never touch tools to the media surface carelessly
- Sterilize loops/pipettes before and after each use
Dispose of Cell Culture Plates Safely
- Autoclave cell culture plates before disposal
- Handle used Petri dishes as biohazardous waste
- Follow lab-specific disposal procedures for used cell culture dishes
Observe Carefully—Don’t Assume
- Compare your cell growth patterns to controls
- Rule out contamination before interpreting your results
- Take photos for documentation, when needed
Bonus Tip: For Imaging or Delicate Samples, Upgrade Your Dish
If you're working with live cell imaging, embryos, or high-resolution microscopy, a standard plastic dish might limit your results. Consider WPI’s FluoroDishes™:
- Thin optical-grade glass bottom that’s as thin as a cover slip
- Exceptional clarity for microscopy, fluorescence, and imaging
- Higher embryo survival rates
- Optional coatings like fibronectin, vitronectin, collagen, or poly-D-lysine
Ready to level up your cell culture work?
