Petri dish – Features, Types, Maintenance, Uses
A Petri dish is a cylindrical lidded dish made of shallow clear glass or plastic, used to hold a thin layer of agar. Used to cultivate bacteria, fungi and other microorganisms. The Petri dish, mounted on a PZT-driven stage, is repeatedly brought into contact with the cantilever tip for a certain period of time and retracted away. Petri dish contaminations are commonplace and personally witnessed by every microbiologist. The vast majority of such contaminations result in nothing more than annoyance following which the Petri dishes are discarded. However, a handful of incidents of contaminations have led to momentous outcomes, the most renowned of which being that perceived by Alexander Fleming on the basis of the immense number of lives saved by penicillin. Petri dish contaminations as reported upon in the literature fall broadly into two categories; those in which the contaminant caused antagonism toward the species being cultured, and those in which the contaminant was established to be a species novum. Accounts of both of these categories of contaminations are set out here.
What is a Petri dish?
- Biologists use a Petri dish (also known as a Petri plate or cell-culture dish) to hold growth medium in which cells can be cultivated, originally cells of bacteria, fungus, and tiny mosses.
- A Petri dish is a clear glass or plastic cylinder with a lid that is used to retain a thin coating of agar. Used to cultivate microorganisms such as bacteria, fungus, and others.
- The Petri dish is named after its inventor, Julius Richard Petri (1852-1921), who worked at the Imperial Health Office in Berlin as Robert Koch’s assistant.
- He created a small, circular, flat-bottomed dish with sides.
- One of the two dishes was somewhat larger than the other and served as a cover and shield. Designed using two fundamental principles: Separation: cultivating microorganisms while isolating them from airborne contaminants, then separating individuals (handlers) and the environment from these bacteria following cultivation. Disclosure / Visibility.
- It is the most prevalent form of culture plate.
- The Petri dish has entered public culture as one of the most frequent things in biology laboratories.
- The term is occasionally spelled with lowercase letters, particularly in non-technical writing.
- Robert Koch, a German physician, invented the predecessor of the Petri dish in 1881 in his home laboratory. As Koch’s assistant at Berlin University in 1887, Petri made the final alterations that are still in use today.
- Alexander Fleming discovered penicillin, the first antibiotic, in 1929 when he observed that mould that had infected a bacterial culture in a Petri dish had killed all the bacteria in the dish.
- Before the development of Petri dishes, microorganisms were cultured in atmosphere-vulnerable test tubes, ancient liquor bottles, and glass jars. The cultures are protected by a lid, yet they are still infected.
- In addition, raising the lid to inspect the contents of the jar frequently allowed condensation and air sediments to enter. As a result, it was unable to form microbe colonies.
Features of Petri dish
- 100% virgin polystyrene, 35/50/70/90/150 mm diameter, customised
- With a designated writing space.
- Easy to use with one hand.
- Gamma radiation for sterilising purposes.
- Packaged in plastic sleeves with thick walls.
- Unique characteristics of the 90mm x 15mm petri dish’s design.
- Digital scale with easy positioning and counting quadrants.
- The unique design (stacking ring) enables simple and secure stacking.
Types of petri dishes
Glassco provides three distinct Petri Dishes:
- Boro 3.3 Glass Petri Dish – These Petri dishes are completely transparent. They can be sterilised and reused. They are printed in white to ensure the correct size of the plate. Boro 3.3 Glass permits the steady diffusion of agar and ensures the absence of visual distortion.
- SG Line Petri Dish – The interior surface of these Petri dishes is lined with soda and is entirely flat. They are clear and free of air bubbles. Lime derived from limestone is added to these plates to improve their chemical resistance.
- Disposable Petri Dish – These indestructible Petri dishes are manufactured from polystyrene. These non-toxic, transparent plates can withstand temperatures up to 121 degrees Celsius.
Types of petri dishes based on material
1. Glass Petri Dishes
- Lab equipment made of glass can be sanitised and reused in an autoclave or laboratory oven.
- Some goods are constructed to survive repeated washings and sanitising.
- Borosilicate and quartz glasses have a strong thermal shock resistance.
- Additional qualities are possessed by proprietary materials such as KIMAX® (Kimble Chase), Pyrex® (Corning), and Zerdour® (Schott Glass). For instance, KIMAX petri dishes may be recommended for applications that require both physical robustness and chemical resistance.
2. Plastic Petri Dishes
- Disposable plastic Petri plates are an excellent alternative for scientific work where cross-contamination may be an issue.
- Fluoroelastomer materials have excellent resistance to heat, oil, and chemicals, although they frequently operate poorly at low temperatures.
- Nitrile has a recommended operating temperature range of -20°C to 135°C, making it a viable option for some low-temperature applications.
- As with EPDM, Neoprene dishes may be used in a wide variety of temperatures and are resistant to UV radiation damage.
- Suppliers of plastic Petri dishes may label their wares as optically unaffected. This is essential for applications requiring the observation of the contents of a cell culture dish, often with a low-power microscope.
Glassco Petri Dishes Features
- Glassco’s Petri dish includes a clear airtight lid that prevents contamination of the cultures.
- The plate is resistant to both heat and chemicals to protect the cultures contained within.
- The rims of the petri dish have been fire-polished for simple and secure handling.
- The extremely transparent glass of the petri dish facilitates precise observations.
How to use Petri dishes effectively in a laboratory?
- Before utilising a Petri dish, it is essential to ensure that it is completely clean and devoid of any microparticles that could interfere with the experiment. You may ensure this by disinfecting every used dish with bleach before reusing it. Be sure to sterilise the Petri dish before to using it.
- To watch the development of bacteria, fill the dish with agar media (prepared with the help red algae).
- Agar media contains nutrients, blood, salt, indicators, antibiotics, and other substances that promote microbial development.
- Invert the Petri dishes and place them upside down in the refrigerator.
- When required, remove the culture plates from the refrigerator and use them after they have returned to room temperature.
- Take a sample of bacteria or any other microbe and either slowly pour it onto the culture or apply it using a cotton swab in a zigzag pattern. Ensure that you are not imposing excessive pressure, as this could destroy the culture.
- Once this is accomplished, cover the Petri dish properly with its lid.
- Allow it to grow for a few days at approximately 37
- Your sample will be ready for research after a few days.
Maintenance of petri dishes
.webp)
- Cleaning: Petri dishes are simple to clean. The dish can be washed under running water or disinfected with bleach, making it ready for reuse.
- Storage: When not in use, the Petri dishes should be stored upside down. To prevent condensation, they should be stored in a cool, dry place or a refrigerator.
- Life: Depending on their use, the Petri Dishes have a lengthy lifespan. Glass Petri dishes can be reused after sterilisation, but disposable Petri dishes are only used once and then discarded.
Precautions
- Before and after using the petri dishes, they should be sterilised.
- Clean up the spills with caution.
- Wear gloves and keep your hands clean while conducting experiments.
- Use only sterile equipment and materials.
Petri Dish Uses
Petri dishes are Used At
- Microbiology Laboratories: In biology, Petri plates are commonly used to produce microorganisms such as bacteria, yeasts, and fungi. It is optimal for organisms that flourish on solid or semisolid surfaces.
- Botany and Agriculture: Petri plates can be used to investigate the early phases of plant germination and to cultivate plants from isolated cells asexually.
- Entomology: Petri dishes may be useful for studying the behaviour of insects and other small creatures.
- Chemistry Labs: Petri dishes are efficient for evaporating solvents and drying precipitates at room temperature or in ovens and desiccators due to their huge open surface.
- Schools and Colleges: In college, it is utilised for laboratory testing and specimen cultivation.
Uses of petri dish in laboratory for:
- Crystallizing
- Cell Culture (Petri dishes are also used for cell cultivation of isolated eukaryotic cells, such as in immunodiffusion experiments, on solid agar or liquid medium.)
- Evaporating
- Drying
- Sample Storage and Display
- Assay
- Contamination Detection and Mapping (Petri dishes can be used to visualise the location of contamination on surfaces such as kitchen countertops and utensils, clothing, food preparation equipment, and animal or human skin).
Advantages of Petri dishes
- Petri dishes or plates are perfect for use in ordinary laboratory procedures. They are laboratory equipment utilised in the field of biology.
- It facilitates the study of cell structure and its colonies by scientists.
- These Petri dishes are necessary for watching seed germination in school and university laboratories.
- Petri dishes include a lid to avoid contamination and atmospheric reactions.
- Reusability is achieved through repeated sterilisation.
- Petri dishes, sometimes called as Peachery Petri Dishes, are available in several sizes and are inexpensive.
References
https://microbiologie-clinique.com/petri-dish.html
https://www.sciencedirect.com/topics/engineering/petri-dish
https://www.glasscolabs.com/product-category/laboratory-glassware/dishes/petri-dishes/
https://www.abdoslifesciences.com/product/petri-dish-ps/
No comments