Precautions when using micropipetting instruments

Micropipetting instruments, such as micropipettes, are precision liquid-taking devices that are widely used in biochemical experiments, molecular biology experiments and other fields. When using it, in order to ensure its accuracy and extend its service life, you need to pay attention to the following matters:

1. Preparation before operation

1. Choose the appropriate range: Select the appropriate pipette range according to the experimental needs, ensuring that its maximum range is not exceeded.

2. Check the status of the pipette: Make sure that all parts of the pipette are intact, especially key parts such as the piston and O-ring, so as not to affect the accuracy of liquid extraction.

2. Liquid absorption process

1. Install the tip: Install the appropriate tip on the pipette and rotate it gently to ensure a good seal.

2. Immersion in liquid: Immerse the tip vertically into the liquid to be aspirated, generally to a depth of 3-5 mm, to avoid the pipette body from contacting the solution.

3. Release slowly: When absorbing liquid, release your thumb slowly and steadily to avoid sudden release, which will cause the solution to be sucked in too fast and rush into the liquid dispenser to corrode the plunger, causing air leakage or damage.

4. Pre-moisten the tip: For liquids such as serum protein solutions or organic solvents that tend to leave a "liquid film" on the inner wall of the tip, the sample solution should be pre-absorbed once to moisten the tip to reduce errors.

3. Discharging process

1. Wall-adhering operation: Attach the tip mouth to the bottom of the inner wall of the container and keep it tilted. Press the button smoothly to the first stop point. Wait for a moment and then press the button to the second stop point to drain the remaining liquid.

2. Complete discharge: After ensuring that the liquid is completely discharged, release the button and lift the pipette so that the tip touches the wall of the container to avoid dripping of residual liquid.

4. Maintenance and maintenance

1. Avoid impact: Do not use the pipette to repeatedly hit the tip to tighten it. This will cause the internal parts to loosen and damage the pipette.

2. Mixing is strictly prohibited: It is strictly prohibited to use a pipette to mix the liquid to avoid damage to the pipette or aerosol pollution.

3. Avoid corrosion: It is strictly prohibited to absorb highly volatile and corrosive liquids (such as concentrated acid, concentrated alkali, organic matter, etc.) to avoid corrosion of the pipette.

4. Regular cleaning: After use, the pipette should be returned to its original place, and the outside of the pipette should be cleaned regularly with a damp cloth. However, do not scrub with organic solvents such as alcohol to avoid damaging the surface coating of the pipette.

5. Professional calibration: In order to ensure the accuracy of the liquid volume delivered by the pipette, it should be calibrated regularly. Newly purchased instruments should be calibrated before use, and measuring instruments in use should also be regularly calibrated and calibrated, and files should be established.

5. Other matters needing attention

1. Avoid high temperatures: Do not grill any part of the pipette with fire, and do not absorb solutions with a temperature higher than 70°C to avoid corrosion of the piston after steam intrusion.

2. Handle the fault correctly: If the solution accidentally enters the pipette column, the pipette should be disassembled as soon as possible, rinse all parts with clean water, wipe them with alcohol, wipe them dry, and then assemble them correctly to restore them to their original state.

When using micropipetting instruments, operating procedures and precautions should be strictly followed to ensure the accuracy of the experiment and the service life of the instrument.