What We Should Pay Attention to When Using Pipette?
How do we correct the pipette when using it to avoid errors and affect the accuracy of the experiment?
1. For liquids with large concentrations and viscosities, errors will occur. To compensate for the error, the amount of compensation can be determined by experiment. The amount of compensation can be set by changing the reading of the reading window with the adjustment knob.
2. The pipette can be calibrated by weighing the weight of the purified water and calculating it using an analytical balance. Note: 1mL of distilled water weighs 0.9982g at 20°C. Do not rotate the button out of the range within the pipette range. Otherwise, the mechanism will be stuck and the pipette will be damaged.
3. When setting the range, please note that the number is clearly displayed in the display window and rotated to the required range.
4. Do not use a large-scale pipette to remove a small volume of liquid, so as not to affect the accuracy. Also, if you need to remove a larger amount of liquid outside the range, use a pipette.
Using a pipette accurately and consistently is crucial in various laboratory and clinical settings. To ensure precision and reliability in your pipetting tasks, here are some important considerations and best practices to keep in mind:
1. Calibration and Maintenance:
- Calibration: Regularly calibrate your pipettes to ensure accuracy. Calibration schedules may vary based on laboratory requirements, but it’s typically recommended annually or after significant servicing.
- Maintenance: Keep your pipettes clean and well-maintained. Follow the manufacturer’s recommendations for cleaning, lubrication, and servicing. Regular maintenance helps extend the lifespan of your pipettes.
2. Pipette Selection:
- Choose the Right Pipette: Select the appropriate pipette model and size for your specific application. Different pipettes have different volume ranges and accuracy levels.
3. Pipette Tips:
- Use High-Quality Tips: Always use high-quality, sterile pipette tips that are compatible with your pipette model. Low-quality or improperly fitted tips can compromise accuracy.
- Pre-Wet Tips: Before pipetting, pre-wet the pipette tips by aspirating and dispensing the working liquid several times. This helps ensure consistent volume delivery.
4. Technique:
- Correct Pipetting Technique: Learn and practice proper pipetting technique, including maintaining a vertical pipette, using a slow and steady plunger press/release, and avoiding rapid plunger release, which can create aerosols.
- Avoid Air Bubbles: Be careful to avoid trapping air bubbles in the tip when aspirating and dispensing liquids. Ensure the tip is fully submerged in the liquid.
- Blow-Out Technique: For accurate delivery, use the “blow-out” technique by aspirating to the desired volume and then expelling any remaining liquid by gently pressing the plunger to the first stop, followed by a quick release.
- Sequential Pipetting: When working with multiple samples, practice sequential pipetting by using the same pipette for all samples before changing to a new pipette. This minimizes variations due to pipette-to-pipette differences.
5. Temperature and Viscosity:
- Temperature: Be aware that the temperature of the liquid can affect its volume. Many pipettes are calibrated at a specific temperature (often 20°C). Adjust for temperature variations if necessary.
- Viscosity: Viscous liquids may require a specific pipette or tip designed for such fluids. Consult the manufacturer’s recommendations.
6. Contamination Prevention:
- Avoid Cross-Contamination: Change tips between samples to prevent cross-contamination. Always use a fresh tip when pipetting different solutions.
- Avoid Pipetting by Mouth: Never pipette by mouth, as it can expose you to potential chemical or biological hazards. Use mechanical pipettes or pipetting aids.
7. Record Keeping:
- Documentation: Maintain thorough records of your pipetting tasks, including pipette model, calibration status, date, operator initials, and any deviations from standard procedures.
8. Safety:
- Safety Precautions: Be aware of any potential hazards associated with the samples you are handling. Use appropriate personal protective equipment (PPE) when necessary.
9. Storage:
- Proper Storage: Store pipettes in an upright position in a designated pipette stand or holder to prevent damage or contamination.
10. Training:
- Training and Certification: Ensure that personnel using pipettes are properly trained and certified in pipetting techniques. Regular training and competency assessments are essential.
By adhering to these best practices, you can maintain the accuracy and reliability of your pipetting tasks, contributing to the overall quality and integrity of your laboratory or clinical work.
