Pipetting is an essential skill in any laboratory, and accuracy is crucial for reliable results. Even small errors in pipetting can lead to big issues in your experiments. If you’re wondering how to make your pipetting more accurate, here are some practical tips you can follow to improve your technique.
Choose the Right Pipette
Using the correct pipette for the job is the first step towards accuracy. Pipettes are designed for different volume ranges, so make sure to use one that suits the volume you need. For example, if you’re handling small volumes, use a micropipette with a low-volume range. Pipetting at the upper or lower limits of a pipette’s capacity can lead to errors.
Pre-Wet the Pipette Tip
One common mistake is not pre-wetting the pipette tip. Before you start your actual sample transfer, aspirate and dispense the liquid a few times. This ensures that the tip is conditioned and prevents any liquid from sticking inside. It makes sure the correct volume is being transferred every time.
Slow and Steady Aspiration
To ensure accurate pipetting, move slowly and steadily when aspirating liquid into the pipette. Pulling the liquid too quickly can cause bubbles or splashes, which leads to errors. A slow and controlled motion guarantees the liquid enters the tip evenly, without leaving gaps of air inside.
Use Consistent Pipetting Techniques
Consistency is key when it comes to accurate pipetting. Hold the pipette at a consistent angle—usually around 20–30 degrees—and avoid tilting it too much. The depth of the tip in the liquid should also be consistent. This helps avoid aspirating air or affecting the volume you’re transferring.
Change Tips Between Samples
Using the same pipette tip for multiple samples can lead to contamination and inaccurate results. Always use a fresh, sterile tip for each new sample to ensure that nothing mixes between them. This is especially important in sensitive applications like DNA or RNA work.
Use Reverse Pipetting for Viscous Liquids
Viscous liquids, like glycerol, tend to stick to the inside of the pipette tip, making it hard to transfer the full volume. Using a technique called reverse pipetting can help. In reverse pipetting, you draw in a little more liquid than you need, then dispense only the exact volume required.
Regularly Calibrate Your Pipettes
Pipettes can lose calibration over time, leading to inaccurate measurements. Regular maintenance and calibration are essential to keep them functioning correctly. You can either calibrate pipettes in your own lab or send them for professional calibration.
Hold the Pipette Correctly
How you hold the pipette matters. Avoid gripping it too tightly, as the heat from your hand can affect its performance. Instead, hold it comfortably by the body, and avoid touching the tip or the top. This helps keep your pipette stable and ensures that you’re pipetting accurately.
Work at Room Temperature
Temperature plays a big role in pipetting accuracy. If you’re working with liquids that are much colder or warmer than room temperature, they can expand or contract, affecting the volume. To avoid this, allow your reagents to reach room temperature before pipetting. This ensures that the liquid is at its normal volume.
Some additional Tips
To improve pipetting accuracy, minimize pipette angle changes, as tilting can lead to volume inconsistencies. For example, when working with small volumes, keep the pipette vertical to avoid errors. Use the correct pipette type for different liquids, such as positive displacement pipettes for viscous substances like oils. Regularly clean your pipette, especially after handling sticky samples, to ensure precise transfers. Taking breaks during long pipetting sessions also prevents fatigue, ensuring better results.
Improve your pipetting accuracy by choosing CytoScientific pipette tips—trusted by laboratories for their superior design and performance. Buy our tips today for more accurate results in your experiments