Petri Dish Usage Guidelines: Cleaning, Types & Precautions

News

News 28 3 月, 2025

A Petri dish is an essential laboratory tool for microbial and cell cultures. It consists of a flat, round base and a lid. Due to its fragile nature, handling it with care is crucial. Proper cleaning, sterilization, and storage are key to maintaining its integrity and ensuring accurate experimental results.

How to Clean a Petri Dish?

1. Soaking

Both new and used glass Petri dishes should be soaked in water to soften residues.
New dishes: Rinse with tap water, then soak in 5% hydrochloric acid overnight.
Used dishes: Immediately immerse in water to prevent proteins and oils from drying, making them easier to clean.

2. Scrubbing

Use a soft-bristled brush and detergent solution to scrub thoroughly, avoiding scratches or damage.
Ensure all areas are cleaned, with no residue left behind.

3. Acid Bath

Immerse dishes in an acid solution (cleaning liquid) for at least 6 hours, ideally overnight to remove any remaining contaminants.
Handle carefully while transferring dishes in and out of the solution.

4. Rinsing

Proper rinsing is crucial for successful cell cultures.
After acid treatment, rinse thoroughly by repeating the “fill-drain” method at least 15 times.
Finally, rinse 2-3 times with distilled water before drying.

5. Sterilization of Disposable Petri Dishes

Plastic Petri dishes are typically pre-sterilized by gamma irradiation or chemical treatment before shipment.

Types of Petri Dishes

By Usage:

Cell Culture Petri Dishes
Bacterial Culture Petri Dishes

By Material:

Plastic Petri Dishes (single-use or reusable)
Glass Petri Dishes (for microbial & cell cultures)

By Size:

Common diameters: 35mm, 60mm, 90mm, 150mm

By Compartments:

Divided Petri Dishes: 2-section, 3-section dishes for multiple samples

Petri Dish Usage Precautions

Before Use: Always clean and sterilize Petri dishes to prevent contamination. Any residual chemicals may alter pH or inhibit bacterial growth.

New Petri Dishes: Wash with hot water, soak in 1-2% hydrochloric acid for a few hours to remove alkaline substances, then rinse twice with distilled water.

For Bacterial Culture:

Autoclave sterilization at 121°C, 15 psi for 30 minutes OR
Dry heat sterilization at 120°C for 2 hours in an oven.

Only sterilized Petri dishes should be used for culturing.