A complete pipetting process consists of the following six steps:
1.Tip installation–rotary installation ■ Use a tip with a suitable pipette range. To ensure good sealing, insert the pipette vertically into the tip, rotate it halfway to the left and right, and tighten it. The recommended pipette volume is 35% -100% of the tip within the range. (Multi-channel pipettes are recommended to use imported tips)
2. Volume setting: rough adjustment / fine adjustment ■ Adjusting from large range to small range is the normal adjustment method, just rotate the scale counterclockwise. ■ When adjusting from a small range to a large range, it should first be adjusted to exceed the set volume scale, and then adjusted back to the set volume. (Do not turn the button out of the range, otherwise, it will jam the mechanism and damage the pipette.)
3. Rinse the tips ■ After installing a new tip or increasing the volume value, the liquid is sucked and discharged two or three times, and the adsorption on the inner wall surface of the tip reaches saturation, ensuring the precision and accuracy of the pipetting work;
4. Imbibition ■ Tip immersion depth when pipetting with different volume • 0.1-2.5ul / 0.5-10ul ≤ 1mm • 2-20ul / 10-100ul / 20-200ul ≤ 2mm • 100-1000ul ≤ 3mm • 1000-5000ul / 2-10ml ≤ 4mm
■ Positive pipetting (low-density solution) 1. Press the button to the stop point; 2. Gently release the button to the starting point to complete the imbibition; 3. Gently press the button to the stop point to drain the liquid; pause for a while and continue to press the button to drain the liquid; 4. Release the button to return to the origin. If necessary, continue pipetting after changing tips.
■ Reverse pipetting (for viscous or volatile liquids) 1. Press the button to the second stop point to imbibe, and gently release the button to the starting point to complete the imbibition. Suck more liquid than set capacity; 2. Gently press the button to the stop point to exclude the liquid with the set capacity; 3. The excess liquid remaining in the tip is discarded with the tip.
5. Drain The tip is close to the wall of the container. Press the discharge button to the stop point, pause slightly, and then press it to the second stop point. This will ensure that there is no residual liquid in the tip. If there is still residue, the tip needs to be replaced.
6. Remove the tip ■ After removing the pipette tip, set the pipette to a large volume. After the pipette is operated, there are a few more TIPS to remember: • Do not use a large-range pipette to transfer small volumes of liquid; • Use a pipette tip that matches the pipette; • Bubbles are generated too quickly when the liquid is imbibed, and the liquid immerses into the pipette to corrode the interior; • The set range must not exceed the valid range of the pipette and damage the pipette; • Pipettes that have sucked liquids should not be placed flat, and the liquid in the tips will easily contaminate the inside of the pipettes; • The pipette should be adjusted to a large scale after each experiment to allow the spring to return to the prototype to extend the life of the pipette; • Check for leaks during use. After imbibing the liquid, suspend it for a few seconds and check whether the liquid level drops. If the liquid leaks, check whether the tip is matched and the spring piston is normal.