Suction and Dispensing When Using Pipettor?

Let’s first introduce the specific operation method of the adjustable automatic liquid dispenser. Use your thumb and index finger to rotate the knob on the upper part of the liquid dispenser so that the number required volume and volume appears in the digital window.

Insert a plastic pipette tip at the lower end of the liquid dispenser and tighten it to ensure airtightness, and then hold it with four fingers together. On the upper part of the liquid container, press the button on the top of the plunger rod with your thumb, press down to the first stop, insert the suction head of the liquid extractor into the solution to be taken, slowly release the button, suck up the liquid, and stay for 1 ~2 seconds.

Standard Single-Channel Fixed Pipettes

Suction (Aspiration)

  1. Select the Correct Pipette:
    • Choose a pipette with the appropriate volume range for the amount of liquid you need to aspirate.
  2. Attach the Proper Pipette Tip:
    • Ensure that the pipette tip is securely attached to the pipette. Use a tip size that matches the volume you are aspirating.
  3. Adjust the Volume Setting:
    • Set the volume on the pipette to the desired amount. Be sure to adjust the volume using the pipette’s adjustment mechanism.
  4. Pre-Wet the Pipette Tip (Optional):
    • Some protocols recommend pre-wetting the pipette tip by aspirating and dispensing the liquid once without the pipette being immersed in the sample. This helps improve accuracy.
  5. Immerse the Pipette Tip:
    • Immerse the pipette tip into the liquid sample to the specified depth. Make sure the tip is fully submerged.
  6. Depress the Plunger Slowly:
    • Depress the plunger button to the first stop slowly. This action draws the liquid into the pipette tip.
  7. Wait for Equilibration (Optional):
    • Some protocols may recommend waiting a few seconds after aspirating to allow the liquid to equilibrate to the temperature of the pipette.
  8. Check for Bubbles:
    • If bubbles are present in the pipette tip, expel the liquid back into the sample and repeat the aspiration process.


  1. Position the Pipette Tip Over the Target Container:
    • Hold the pipette tip over the target container where you want to dispense the liquid.
  2. Depress the Plunger to the Second Stop:
    • Depress the plunger button to the second stop. This expels the liquid from the pipette tip.
  3. Wait for a Moment:
    • Allow a moment for any residual liquid to exit the pipette tip completely.
  4. Touch the Pipette Tip to the Container Wall:
    • Touch the pipette tip to the inside wall of the container to ensure complete dispensing.
  5. Eject the Pipette Tip:
    • Eject the pipette tip using the appropriate mechanism on the pipette. Dispose of used tips in a designated waste container.
  6. Final Plunger Push (Optional):
    • Some protocols recommend pushing the plunger to the final stop to expel any remaining liquid in the tip. This is particularly useful when working with viscous liquids.
  7. Wipe the Outside of the Pipette:
    • Wipe the exterior of the pipette with a laboratory wipe to prevent cross-contamination between samples.
  8. Perform Calibration Checks (As Needed):
    • Regularly check and calibrate the pipette according to the manufacturer’s recommendations to ensure accurate and precise pipetting.

Additional Tips

  • Use Consistent Technique:
    • Maintain a consistent and smooth motion when operating the plunger to ensure accuracy and precision.
  • Avoid Over-Aspiration:
    • Avoid over-aspirating the liquid to prevent damage to the pipette and ensure accurate dispensing.
  • Minimize Air Displacement:
    • Minimize the introduction of air bubbles during aspiration to prevent inaccurate volume measurements.
  • Practice Good Pipetting Posture:
    • Maintain a comfortable and ergonomic posture while pipetting to reduce the risk of repetitive strain injuries.
  • Follow Laboratory Protocols:
    • Adhere to laboratory protocols and standard operating procedures (SOPs) for pipetting techniques and safety.

How to use the pipettor?

Set the pipetting volume: adjusting from a large range to a small range is the normal adjustment method, just rotate the scale counterclockwise. This operation for a long time will cause the parts of the pipettor to lose due to the impact, which will seriously cause the knob to adjust the scale to get stuck.

Aspiration and dispensing

Vertical aspiration: the pipette tip is immersed below 3mm of the liquid surface. Before aspiration, the pipette tip is pre-rinsed in the liquid 2 to 3 times to ensure the accuracy and accuracy of the pipetting (because a layer of “liquid film” will remain on the inner wall of the pipette tip, resulting in an error due to the small discharge volume).

Slowly inhale and release slowly to prevent the sudden release of the solution and the inhalation of the solution is too fast, which will rush into the liquid extractor and corrode the plunger and cause air leakage. If the amount is small when dispensing liquid, the pipette tip should be secured to the inner wall of the container. Check if there is any leakage during use.

The method is to suck the liquid and place it vertically in the air for a few seconds to see if the liquid level drops. If it leaks, check whether the suction nozzle matches and whether the spring piston is normal. Liquid with high concentration and viscosity: error will occur. The compensation amount to eliminate the error can be determined by experiment. The compensation amount can be set by changing the reading of the reading window with the adjusting knob. (Reverse pipetting technology can be used to pipettor high viscosity liquids).
Pipettor is a sucking liquid that should not lie flat: the liquid in the pipette tip can easily contaminate the inside of the pipette and may cause the pipettor’s spring to rust. The scale of the pipettor should be adjusted to the maximum after each experiment to let the spring return to the prototype to extend the service life of the pipettor.

pipettor calibration: the method can be used to calibrate the pipettor by weighing the weight of the pure water taken with an analytical balance and calculating it. 1mL of distilled water weighs 0.9982g at 20°C. The pipettor is strictly prohibited to absorb highly volatile and corrosive liquids (such as concentrated acid, concentrated alkali, organic matter, etc.). Never use a pipettor and mix the liquid.

Do not use a large-range pipettor to pipette small volumes of liquid, so as not to affect accuracy. At the same time, if you need to pipettor a larger amount of liquid outside the measuring range, please use a pipettor. If liquid enters the piston chamber accidentally, remove the contaminants in time. Clean the outer wall of the pipettor regularly. You can use 95% alcohol or 60% isopropanol, wipe it with distilled water, and let it dry naturally.