Multi-channel pipette pipetting operation steps and precautions

Before conducting any experiment, it is important to be familiar with and master the correct use of the instrument. Multi-channel pipettes, with their ability to transfer multiple portions of the same volume of liquid at the same time, greatly simplify experimental procedures and are especially suitable for high-throughput experimental scenarios. However, incorrect operation may not only lead to deviations in experimental results, but may also pose a threat to the safety of experimental personnel. This article will elaborate on the pipetting operation steps and precautions of multi-channel pipettes. I hope it will be helpful to you:

1. Preparation work

1. Disinfection and cleaning:

1>Use 70% alcohol to wipe the pipette and experimental table to ensure no contamination.

2> Place the multi-well plate directly in front of the experimental table, and pour the liquid to be removed into a clean and sterilized container, such as a V-shaped groove.

2. Install the suction head:

1>Select the appropriate tip according to the pipette model and experimental needs.

2> Align the first channel of the pipette with the first tip, insert it at an angle, shake it back and forth slightly, and tighten it. Make sure that the tip slightly exceeds the O-ring after insertion, so that the pipette and the tip fit tightly. .

3> Be careful not to use excessive force to avoid damaging the suction head or making it difficult to withdraw the suction head.

3. Set the pipetting volume:

1>First use the discharge button to quickly adjust the capacity value to close to the expected value.

2>When the volume value is close to the expected value, place the pipette horizontally in front of your eyes, and slowly adjust the volume value to the expected value through the adjustment wheel to avoid visual errors.

3> When setting the capacity, just rotate it directly from the large value to the small value; but when adjusting from the small value to the large value, you need to turn it over one-third of a turn and then return to ensure accuracy.

2. Liquid aspiration operation

1. Pre-wash the tips:

1>After installing a new tip or increasing the capacity value, the liquid to be transferred needs to be sucked and discharged two to three times (four to six times for organic solvents or highly volatile liquids) to ensure pipetting precision and accuracy.

2. Vertical aspiration:

1> Hold the pipette in your hand and press the button with your thumb to the first stop position.

2>Immerse the sampler vertically into the liquid surface by 2-3mm, release your thumb slowly and steadily, and slowly inhale the liquid.

3> Ensure that the pipette is perpendicular to the liquid surface to avoid inhaling air due to tilting of the pipette or insufficient immersion distance.

4> Try to avoid using a pipette to absorb corrosive liquids to prevent corrosion of the pipette.

3. Drainage operation

1. Close to the container wall:

1>When draining liquid, first place the suction head close to the wall of the container.

2> Press the discharge button to the first stop position, pause briefly, and then press it to the second stop position to ensure that there is no residual liquid in the suction head.

4. Follow-up processing

1. Remove the suction head:

1>After the pipetting process is completed, press the tip ejection arm to remove the discarded tip into the waste bucket.

2> Note that waste tips must not be mixed with new tips to avoid cross-contamination.

2. Pipette storage:

1> Place the pipette on the pipette holder promptly after use and do not leave it lying around.

2> Do regular inspection and calibration of the pipette to ensure the accuracy of the pipette.

5. Things to note

1. Avoid collision:

1>Never use the pipette to repeatedly hit the tip to tighten it, as this will cause internal parts to loosen and damage the pipette.

2. Laying flat problem:

1> The pipette gun that absorbs liquid should not be placed flat to prevent the liquid in the tip from contaminating the inside of the gun and causing the spring to rust.

3. Spring protection:

1>The scale of the pipette should be adjusted to the maximum range after each experiment to allow the spring to return to its original shape to extend the service life of the pipette.

Continuous attention and compliance with the precautions can ensure the accuracy and safety of multi-channel pipette pipetting operations. This includes personal safety protection in place, regular calibration and maintenance of pipettes, and the cleanliness and standardization of the experimental environment. These measures not only help improve experimental efficiency, but also ensure the smooth progress of the experimental process and the reliability of experimental results.