Sources of Laboratory Contamination

Introduction

When performing experiments in a laboratory, it is essential to ensure that the results obtained are accurate and reliable. However, contamination in laboratory samples can affect the outcome of experiments, leading to inaccurate results. It is, therefore, important to understand the sources of contamination in a laboratory, in order to prevent it. In this blog post, we will discuss three common sources of laboratory contamination and how to prevent them.

Equipment Contamination

One of the significant sources of laboratory contamination is equipment. Equipment such as pipettes, beakers, and test tubes can harbor contaminants that may affect the accuracy of the results. To prevent equipment contamination, it is essential to clean and sterilize them thoroughly. Ensure that the equipment is cleaned immediately after use and sterilized using appropriate methods such as autoclaving or chemical disinfection. Contamination can also occur due to the use of expired or damaged equipment. Hence, it is necessary to check the expiry dates and the integrity of the equipment before use.

Personnel Contamination

Personnel can also be a significant source of contamination in a laboratory. Skin cells, hair, and clothing fibers can all contribute to contamination in laboratory samples. To prevent personnel contamination, laboratory staff must adhere to good laboratory practices. This includes wearing appropriate personal protective equipment, such as lab coats, gloves, and face masks, as well as keeping their work area clean and organized. Staff should also avoid eating, drinking, or applying cosmetics in the laboratory, as these can all contribute to contamination.

Airborne Contamination

Airborne contaminants such as dust, pollen, and microorganisms can also affect the accuracy of laboratory results. These contaminants can enter the laboratory through open windows or doors, as well as through the air conditioning system. To prevent airborne contamination, laboratories must be equipped with air filtration systems that remove contaminants from the air. The laboratory must also be kept clean and free from clutter that can harbor contaminants.

Conclusion

Contamination in a laboratory can have a significant impact on the accuracy and reliability of experimental results. It is, therefore, essential to understand the sources of contamination and how to prevent them. By following good laboratory practices, such as cleaning and sterilizing equipment, adhering to appropriate personal protective measures, and maintaining a clean laboratory environment, laboratory staff can help to ensure the accuracy and reliability of their results.

Study

Why some lab plastic consumables made by PP and some made by PS material?

Polypropylene (also known as PP) and polystyrene (also identified as PS) are two types of commonly used polymers in plastic laboratory consumables. PP and PS are similar in many applications, but there are some inherent differences between them that make them more appropriate for specific applications.

PP is a thermoplastic polymer. It is commonly used to manufacture plastic laboratory supplies such as beakers, bottles, flasks, specimen containers, test tubes, and many others. Polypropylene is exceptionally tough, unbreakable, flexible and resistant to many chemicals, acids, and bases. It also has a high level of heat resistance. Depending on the grade, polypropylene has a melting point of 130℃, up to 171℃. Many polypropylene products are autoclavable due to this high level of heat resistance. In contrast with polystyrene products, which are disposed of after only a single use, polypropylene can be reused over and over again. Therefore, polypropylene products can be considered as cost-effective alternatives to their glass equivalent. The durability, high chemical resistance, and high level of temperature tolerance of polypropylene products make them very versatile in many laboratory and industrial applications.

PS is a polymer made from the monomer styrene, a liquid hydrocarbon that is commercially manufactured from petroleum. At room temperature, polystyrene is normally a solid thermoplastic, but can be melted at higher temperature for extrusion, then resolidified. Polystyrene is great for general sample storage and transport and is commonly used in lab supplies such as test tubes, microplates, and petri dishes due to is glass level transparency. It is a highly used plastic all over the world because it is usually offered at a lower price than many other plastics. Polystyrene is environmentally friendly because it can be recycled. Although polystyrene offers some resistance to acids and bases, it is not as resistant against some chemicals as polypropylene. Polystyrene cannot withstand heat above 100°C and are disposed after only a single use.

how to distinguish between PP and PS?

• The difference in sound: PS material is tougher, the percussion sound is clearer. PP sound is dull because the PP material has adequate toughness but lacks hardness.
• The difference in appearance: PS can be quite clear, PP is not, but it still has the appearance of frosted glass.
• The difference in texture: PP has good toughness, while PS is more rigid.

Generally speaking, the same thickness of PP and PS products, transparency: PS>PP, hardness: PS>PP, toughness PP>PS.