Sterile Technique

Summary

This instructional video from Addgene emphasizes the importance of aseptic technique in lab sciences. It covers personal protective equipment, setting up a clean workspace, and maintaining sterility. Key points include wearing lab coats and gloves, keeping workspaces organized, and using alcohol and flame to sterilize tools. The video also demonstrates proper handling of agar dishes and bottles to prevent contamination, ensuring a safer and more effective laboratory practice.

Takeaways

• 🔬 Aseptic technique is crucial for success in fields like microbiology, molecular biology, and cell biology.
• 🧼 Personal protective equipment (PPE) such as lab coats, gloves, and safety glasses are essential for maintaining aseptic conditions.
• 👕 Ensure arms and wrists are covered to minimize the risk of contaminating samples with body flora.
• 🧤 Gloves protect both the user and the material from contamination; change them when necessary.
• 🧹 Clear the workspace of unnecessary materials and keep clean and dirty items separate to maintain a clean working environment.
• 🔥 Use a Bunsen burner or candle jar to create a sterile field, and keep the surrounding area free of flammable materials.
• 🍶 Wipe down workspace and equipment with 70% alcohol to disinfect surfaces before starting work.
• 🔍 Inspect all materials for signs of contamination or compromised sterility, including checking autoclaved items and sealed containers.
• 🔥 Sterilize metal objects like forceps by flaming after dipping in 70% alcohol for reuse in the lab.
• 🧫 When working with agar dishes, hold the lid at an angle to inoculate to prevent contamination from body flora.
• 🌐 Visit Addgene's website for more resources on aseptic technique, protocols, and scientific sharing.

Q & A

What is aseptic technique and why is it important in scientific fields?

Aseptic technique is a critical skill in fields such as microbiology, molecular biology, and cell biology, which involves maintaining a sterile environment to prevent contamination of samples and reagents.

What personal protective equipment is recommended for working in a lab?

Appropriate personal protective equipment includes a lab coat, gloves, and safety glasses if necessary.

How can body flora be a source of contamination in a lab setting?

Body flora can contaminate reagents and samples, so it's important to cover arms and wrists with a cuffed lab coat or disposable arm cuffs to reduce this risk.

What are some best practices for maintaining glove cleanliness in the lab?

To keep gloves clean, avoid touching skin, hair, cell phones, writing utensils, or other unsterilized objects, and always change gloves if they come into contact with something unsterile or when starting a new task.

How should a workspace be organized to minimize contamination risks?

The workspace should be cleared of unnecessary materials, with clean and dirty items separated and within arm’s reach. It's recommended to work from left to right, with clean items on the left and waste bins on the right.

Why is it important to wipe down workspaces and pipettes with 70% alcohol?

Wiping down workspaces and pipettes with 70% alcohol helps to disinfect surfaces and prevent contamination of materials and samples.

How can you check if autoclaved items have maintained their sterility?

Check autoclaved items for color changes in the indicator tape to ensure sterility. For foil-covered items, check for tears or holes, and for capped items, ensure the cap is tightly sealed.

What is the proper way to handle foil when working with sterile containers?

Gently loosen the edges of the foil before starting work, lift it with one hand to keep it upright, and hold it in your hand rather than putting it down to prevent contamination of the sterile side.

How should you handle glass bottles containing sterile liquids to maintain sterility?

Gently loosen the cap before starting, remove it with one hand without placing it on the lab bench, and pass the bottle neck through a flame before and after use to sterilize it.

What method can be used to sterilize metal objects like forceps and spreaders in the lab?

Dip the metal objects in 70% alcohol, pass the alcohol-dipped portion through a flame to ignite and burn off the alcohol, and cool the hot tip on a sterile surface before use if it's for live cultures.

How can you reduce the risk of body flora contamination when working with agar plates?

Hold the lid of the agar dish at a 75-90 degree angle towards you and inoculate from behind to form an additional barrier against contamination.

Outlines

00:00

🔬 Aseptic Technique Essentials

Meghan, a scientist at Addgene, introduces aseptic technique as a vital skill for fields like microbiology, molecular biology, and cell biology. The video covers key strategies for aseptic technique, emphasizing the importance of personal protective equipment (PPE) such as lab coats, gloves, and safety glasses. It advises on covering arms and wrists to minimize contamination risk, changing gloves when necessary, and setting up a clean workspace. The video also instructs on maintaining sterility, checking materials for contamination, and proper handling of agar dishes, glass bottles, and metal instruments. It concludes by promoting Addgene's resources for further learning.

Keywords

💡Aseptic technique

Aseptic technique refers to the practice of keeping an environment free from living microorganisms, such as bacteria, to prevent contamination. In the video, this technique is crucial for success in fields like microbiology and molecular biology. The script emphasizes the importance of maintaining sterility while working with samples to avoid contamination, which could compromise the integrity of experiments.

💡Personal protective equipment (PPE)

Personal protective equipment includes items like lab coats, gloves, and safety glasses that protect individuals from harmful substances or conditions. The script highlights the necessity of wearing PPE to prevent contamination of samples with body flora and to protect the user from potential hazards in the lab.

💡Sterility

Sterility is the state of being free from all forms of life, particularly microorganisms that could cause contamination. The video underscores the importance of maintaining sterility during laboratory procedures, such as when handling agar dishes or working with sterile liquids, to ensure the accuracy and reliability of scientific experiments.

💡Contamination

Contamination in the context of the video refers to the unwanted presence of microorganisms or other substances that can compromise the results of an experiment. The script provides various strategies to minimize contamination, such as using aseptic technique and personal protective equipment.

💡Lab coat

A lab coat is a protective garment worn in laboratories to protect both the wearer and the samples from contamination. The script specifies that a lab coat should have cuffs to cover the wrists, which is a detail highlighting the importance of covering the entire arm to reduce the risk of contamination.

💡Gloves

Gloves are a type of personal protective equipment used to prevent direct skin contact with potentially hazardous materials and to protect samples from contamination by body flora. The video script advises against touching unsterile objects with gloves and changing them when necessary to maintain sterility.

💡Workspace

A workspace in a laboratory setting is the area where experiments are conducted. The script provides guidance on setting up a clean workspace by clearing unnecessary materials and organizing items for efficient work flow, which is essential for maintaining aseptic conditions.

💡Bunsen burner

A Bunsen burner is a type of gas burner used in laboratories to produce a single flame, often for sterilization purposes. The video mentions using a Bunsen burner to create a flame that can be used to sterilize the necks of bottles or other instruments before use.

💡Alcohol

In the context of the video, alcohol, specifically 70% alcohol, is used as a disinfectant to wipe down workspaces and equipment. The script describes the process of wiping down the workspace with alcohol and allowing it to evaporate, which is a common method for decontaminating surfaces in a lab.

💡Indicator tape

Indicator tape is used on autoclaved items to show whether they have been adequately sterilized. The script mentions checking the color change of the indicator tape as a way to verify that sterility has been maintained after autoclaving.

💡Agar dishes

Agar dishes are used in laboratories to culture microorganisms, such as bacteria. The video script provides instructions on how to handle agar dishes to minimize the risk of contamination, emphasizing the importance of not fully removing the lid and working from behind it to maintain a barrier against contaminants.

Highlights

Aseptic technique is crucial for success in microbiology, molecular biology, and cell biology.

Personal protective equipment includes lab coats, gloves, and safety glasses.

Body flora can cause contamination in reagents; cover arms and wrists to reduce risk.

Gloves protect both the user and the material from contamination.

Change gloves if touching unsterile objects or starting a new task.

Clear workspace of unnecessary materials and set up materials within arm’s reach.

Use a bunsen burner or candle jar with caution, keeping the surrounding area clear.

Wipe down workspace and pipettes with 70% alcohol before starting work.

Inspect materials for contamination and ensure sterility, checking autoclaved items' indicator tape.

Handle foil-covered bottles and beakers carefully to maintain sterility.

Work quickly to minimize exposure of sterile items to the environment.

Sterilize metal objects like forceps and spreaders with alcohol and a flame.

Cool hot instruments before contacting live cultures to avoid killing the specimen.

When working with agar dishes, do not fully remove the lid to reduce body flora contamination.

Inoculate agar plates from behind, using the lid as a barrier against contamination.

For more information on aseptic technique, visit Addgene’s website for videos, protocols, and blog posts.

Transcripts

Hi, I'm Meghan, a scientist at Addgene

Aseptic technique is a critical skill for success in numerous fields such as microbiology,

molecular biology or cell biology.

In this instructional video we will provide an overview of some of the key strategies

of aseptic technique, including personal protective equipment, setting up a clean workspace and

maintaining sterility while working.

Before beginning any experiment make sure that you are wearing the appropriate personal

protective equipment, including a lab coat, gloves and, if necessary, safety glasses.

As we mentioned during our protocol on “Getting Started With Tissue Culture”, body flora

can be a common cause of contamination in reagents.

To reduce the risk of contaminating your samples with body flora, ensure that your arms and

wrists are covered by a cuffed lab coat or disposable arm cuffs.

While gloves are meant to protect users from the material they are working with, they also

protect the material from user contamination.

To keep your gloves clean, avoid touching your skin and hair, as well as your cell phone,

writing utensils, or other unsterilized objects.

Always change your gloves if you touch something unsterile or are starting a new task.

Before beginning any task, clear the workspace of unnecessary materials.

Set up all materials so that they are in arm’s reach with clean and dirty items clearly separated.

We recommend working from left to right with all clean items stored on the left and waste

bins to the right.

If you are going to be using a bunsen burner or candle jar, make sure that the space around

the burners are free of loose papers or laboratory wipes.

Finally, wipe down the workspace and pipettes with 70% alcohol and allow it to evaporate.

Before beginning a task, examine all of your materials for signs of contamination or signs

that the sterility may have been compromised.

Check all autoclaved items to ensure that the indicator tape has changed colors.

For items that are covered with foil check for tears or holes for capped items, ensure

that the cap has been tightly sealed.

When working with agar dishes, examine the dishes for signs of microbial growth.

Foil is often used as a cover for bottles and beakers.

Before beginning your work, gently loosen the edges of the foil, so it is easier to

remove.

When ready, gently lift the foil with one hand and keep it upright, to prevent contamination

of the sterile side.

While working, keep the foil in your hand rather than putting it down on the lab bench.

Work quickly so that the beaker does not sit uncovered for an extended period of time.

When working in the lab with sterile liquids in glass bottles, gently loosen the cap before

starting.

Using one hand, remove the cap from the bottle.

To prevent the sterile side of the cap from becoming contaminated, do not put the cap

on the lab bench.

Instead hold it in your hand upright as you work.

While holding the bottle at an angle, gently pass the neck of the bottle through the flame.

Before recapping, pass the neck of the bottle through the flame a second time.

If you are going to use the bottle again, you can leave the cap loosely sitting on the

top of the bottle.

Once you are finished, however, be sure to cap the bottle tightly.

Metal objects such as forceps and spreaders are used and reused frequently in the lab.

While these items can be sterilized in an autoclave, it is often more convenient to

disinfect with alcohol and a burner.

To sterilize, dip the portion of the instrument that will be used for the procedure in 70%

alcohol.

Pass the alcohol-dipped portion of the instrument through the flame of the burner to ignite

and then allow the alcohol to burn off.

If you are going to use the instrument on a live culture, such as bacteria, touch the hot tip to the inside

of a sterile tube or the surface of an uninoculated culture to cool before contacting the specimen.

Agar dishes are used in the lab to culture bacteria such as E. coli.

To reduce the risk of body flora contamination when working with agar plates, do not fully

remove the lid of the agar dish.

Instead, hold the lid at 75-90 degree angle toward you and inoculate from behind.

The lid will form an additional barrier against unwanted contamination.

Thank you for watching this aseptic technique video.

For more useful videos, protocols or blog posts please visit Addgene’s website.

Addgene - a better way to share science.