For those of us who calibrate daily, repeated pipetting procedures are almost second nature. In fact, a metrology-centric calibration program should provide the necessary standardized expertise for proper performance evaluation and maintenance. However, regularly reviewing the basics of exercises and procedures can refresh your skills, correct mistakes, and remind you that even the smallest mistakes can have a big impact on a lab space. Knowing your process and mastering your chemistry lab supplies or biology techniques will make a huge difference in your success or failure. So let's get back to the basics to ensure the highest quality service and measurements at every turn, here are 5 things you need to know about pipette tips:
1. Correct fit: To ensure accurate results and reduce the risk of error, be sure to use trial and error when installing pipette tips. The correct tip will fit easily without applying a lot of force and will stay on the pipette.
2. If...: If the tip ejector is not releasing the tip properly, it is most likely the wrong tip. If the pipette seems to be working fine, but liquid is leaking, assume it might just be the wrong tip. Many tips are colored to match the corresponding pipette; if the color does not match, the tip may not fit the pipette. For example, yellow tips are used for pipettes with yellow markings, such as 20-200uL pipettes.
3. Sealing Ring: To establish a seal between the tip and the pipette, a sealing ring located on the pipette nozzle can be a useful feature. While not necessary, these rings help minimize "water leaks" and accuracy, and reduce errors during testing.
4. Low retention tips: With today's air displacement pipettes, all liquid in the pipette tip is part of the measured volume. Low retention tips reduce liquid residue adhering to the inside walls of the tip and maximize the use of liquid dispensed by the tip. This option is best when performing tasks that require measuring the volume down to the lowest uL volume.
5. Barrier/Filter Tips: Barrier tips (or filter tips) contain a liquid barrier (sometimes called a filter) located in each tip to prevent pipette contamination. The barrier prevents liquid from entering the pipette during use. Cross-contamination can occur with even the slightest technical error, so barrier tips are a good precaution.
pipette tips
Experienced lab technicians should be able to remove these five basic pipetting reminders from the quality checklist. However, if any of the above reminders trigger the lightbulb, indicating that you overlooked something in your pipetting practice, be sure to revisit your process. After all, it's never a bad idea to refresh your daily routine.
