How to Use a Micropipette

What is the Purpose of a Micropipette?

A micropipette is a crucial laboratory tool for scientists and lab workers. It is a highly precise instrument used to measure and transfer very small volumes of liquids, gels, or other substances for a variety of purposes. 

Micropipettes measure liquid in microliters (µL) with typical volumes ranging from 0.1µL to 1000µL. The right volume range depends on your specific lab application and needs.

Micropipettes have important uses for a variety of applications in biological, chemical, and medical labs where precise liquid handling is key. This includes Polymerase Chain Reaction (PCR), Cell Culture, Drug Research, Genetic Research, and Pharmaceutical Development, among other industrial uses. 

The high level of accuracy of micropipettes make them essential for scientists and lab technicians who have experiments, assays, or processes where even small errors in volume can have significant issues. 

It’s needless to say that micropipettes have great purpose in every laboratory and are at the heart of much of our work.

Top 8 Micropipette Uses in a Laboratory

Micropipettes are essential tools in laboratories, particularly in biological, chemical, and medical research. When considering the transfer of very small volumes of liquid with high precision and accuracy, the main uses of micropipettes include:

1. Sample preparation:

   Transferring precise volumes of liquids for experiments, such as preparing DNA samples, cell cultures, or solutions.

2. Molecular biology:

   Used extensively for tasks like PCR (Polymerase Chain Reaction), DNA sequencing, and cloning, where exact amounts of enzymes, buffers, and nucleic acids are needed.

3. Quantitative analysis:

   Measuring and dispensing liquids for assays, such as enzyme-linked immunosorbent assays (ELISA), where precise reagent volumes are crucial for accurate results.

4. Cell biology:

   Transferring small volumes of media, drugs, or solutions to cell cultures, or preparing samples for microscopy.

5. Biochemical reactions:

   Setting up reactions that require accurate and small quantities of reagents, such as enzyme reactions or protein purification.

6. Pharmaceutical and clinical labs:

   Used in drug testing and diagnostics to handle minute volumes of chemicals, blood, or other fluids.

7. Serial dilutions:

   Micropipettes are used to create serial dilutions, allowing researchers to systematically reduce the concentration of a substance.

8. Microinjection:

   In some advanced applications, micropipettes can be used for injecting substances into cells or embryos, common in genetic engineering.

How to Use a Micropipette

A micropipette works fairly simply: a vacuum is created inside the pipette to allow for precise aspiration and dispensing of small volumes of liquid. Here are the five steps to follow when using a micropipette:

1. For Adjustable Pipettes, Set the Volume

   • The dial or knob on the pipette allows for volume adjustment. The user sets their desired volume for the liquid they want to aspirate, measured in microliters (µL). Fixed-volume pipettes do not contain this feature, thus the step may be skipped.

2. Attach a Micropipette Tip

   • Disposable pipette tips attach to the end of the pipette to aspirate and dispense liquid. Different volumes of liquid require different tips to ensure accuracy and avoid contamination.

3. Aspirate the Liquid

   • To aspirate, or “suck up”, the liquid one starts by depressing the plunger to the first stop (a preset resistance point) and then inserting the pipette tip into the liquid. 
   • Next, releasing the plunger creates the necessary vacuum to draw the liquid up into the pipette tip. The volume of liquid that is drawn will match the volume setting on the micropipette. 

4. Dispense the Liquid

   • To release the liquid from the micropipette, the user places the tip into whichever vessel they want to dispense the liquid and the plunger is pressed past the first stop to the second stop. 
   • The liquid expels from the tip, with the second stop ensuring all liquid is fully ejected. 

5. Eject the Tip

   • After dispensing the liquid, the user presses the tip ejector button to discard the used tip. This avoids contamination of the pipette itself.

To learn more about how to successfully use a micropipette, check out this video from the University of Leicester.

10 Tips to Master Your Micropipetting Technique

Micropipetting isn’t rocket science, but it does require correct technique. Mastering micropipetting technique is essential for accuracy and precision in laboratory experiments. Here are some tips to help improve your micropipetting skills.

1. Choose the Right Pipette and Tip

   • Select the correct micropipette: Use a micropipette with a volume range appropriate for your sample. It's generally known that pipettes can trend towards more accurate measurements at the upper end of their ranges.
     
     This is due to air displacement principles, as air compression and liquid evaporation are more significant when measuring smaller volumes.
     
     Frequent and on-schedule calibration is the key to instruments operating within range
   • Use the right tips: Always use pipette tips that fit the pipette snugly and are sterile to avoid contamination. Check for low-retention tips if working with viscous liquids.

2. Set the Volume Correctly

   • Adjust the volume by turning the dial slowly to avoid damaging the internal mechanism. Don’t go past the minimum or maximum volume.

3. Proper Pipetting Technique

   • Pre-wet the tip: Aspirate and dispense liquid at least once before pipetting to pre-wet the tip. This ensures accurate volume delivery.
   • Hold the pipette vertically: Keep the pipette vertical, especially when drawing liquids. Tilting the pipette can result in inaccurate volumes.
   • Immerse the tip correctly: Only immerse the tip slightly below the surface of the liquid (2-3 mm for small volumes and up to 6 mm for larger volumes). Going too deep can cause liquid to cling to the outside of the tip.
   • Use consistent speed and pressure: Press the plunger smoothly and at a constant speed. 

4. Properly Aspirating Liquids

   • Slowly release the plunger after pressing it to the first stop to avoid creating bubbles in the liquid.
   • Let the liquid rise into the tip steadily. If you aspirate too quickly, it can lead to air bubbles and inaccurate volume.

5. Properly Dispensing Liquids

   • Press the plunger to the first stop to dispense the liquid. Once the liquid is dispensed, press to the second stop to expel any residual liquid in the tip.
   • Touch the tip to the side of the receiving container to prevent liquid from clinging to the tip during dispensing.

6. Avoid Contamination

   • Change tips between samples to avoid cross contamination.
   • Avoid touching the tip to surfaces or liquids that could introduce contaminants.
   • Use filtered tips when working with sensitive samples like RNA or DNA.

7. Practice Proper Technique

   • Repeatedly practice micropipetting using a balance to check the accuracy of the volume pipetted. This will help refine your hand-eye coordination and muscle memory.

8. Use Reverse Pipetting for Viscous or Foamy Liquids

   • For viscous or volatile liquids, use the reverse pipetting technique to ensure accurate volume handling:
     1. Press the plunger to the second stop before immersing the tip.
     2. Aspirate liquid and dispense to the first stop.
     3. Discard any excess liquid from the tip by pressing to the second stop.

9. Maintain Your Pipette

   • Clean the pipette regularly, especially when handling different sample types.
   • Regularly calibrate your pipette to ensure it remains accurate.

10. Relax and Avoid Fatigue

    • Micropipetting for long periods can lead to hand fatigue or even a repetitive strain injury. Use an ergonomic pipette and take breaks to prevent discomfort, which can affect your precision.

Check out this video from BioNetwork to learn the best use of a micropipette in your laboratory:

Common Things to Avoid When Micropipetting

As you learn to master your micropipette technique, there are a few common mistakes and errors that will be helpful to avoid.

1. Using the Wrong Tip

   • It is important to ensure that your pipette tip is the correct type and volume for your pipette and application. Shop a variety of universal pipette tips and LTS compatible tips from Pipette.com.

2. Pipetting at the Wrong Angle

   • Always hold the pipette at a 90-degree angle when aspirating and dispensing to avoid introducing air bubbles or getting inaccurate volumes.

3. Not Handling with Care

   • Don’t jerk your pipette around, force the volume dial, attempt to jam tips on to your pipette, or drop your pipette on the ground. Any of these errors could cause damage to your pipette.;

4. Improper Storage

   • Ensure your pipettes are stored correctly in their appropriate pipette stands to avoid damage and wear.

5. Trying to Fix Damage Yourself

   • Damage, it happens to the best of us. However, don’t make matters worse by attempting to fix damage to your pipette by yourself.
     
     Turn to the experts at Pipette.com where we have the largest inventory of spare parts in the industry. With quick turnaround times and friendly, professional service we will have your pipette back to you as good as new.

6. Not Keeping Your Pipette Properly Calibrated

   • Routine calibration is essential to maintaining accurate, reliable micropipettes. Using a pipette out of calibration can cause errors in your volumes.

Pipette.com - Your All-in-One Micropipetting Solution

Pipette.com is your one stop shop for all things micropipette! Not only do we have a massive inventory of products to supply your laboratory, we provide incredible repair and calibration services as well.

Browse Pipette.com, or check out some of our top pipette product categories below:

• Single Channel Pipettes
• Multi Channel Pipettes
• Refurbished Pipettes
• Eppendorf Pipettes
• Rainin Pipettes
• Gilson Pipettes
• Pipette Tips

Our website is simple and easy to use, but if you need help finding something or want to discuss your buying needs you can connect with one of our account managers at info@pipette.com or through the link below.

Pipette.com’s calibration and repair lab is an ISO 17025-accredited and FDA-registered facility servicing nationwide for over 20 years. We work with labs of all sizes and provide excellent services for products of all brands and models. We offer in-lab or onsite services at a variety of service levels to fit your needs and budget.

We would love to work with you, so let’s get the conversation started!

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