You must know about the suction head of laboratory pipette
1. Use a suitable suction head:
In order to ensure better accuracy and precision, it is recommended that the pipetting volume be within the range of 35% – 100% of the measuring range of the suction head.
- Installation of suction head:
For most brands of pipettes, especially multi-channel pipettes, it is not easy to install the suction head: in order to pursue good sealing, it is necessary to insert the pipette handle into the suction head, rotate it left and right or shake it back and forth, and tighten it with force. Some people will repeatedly hit the suction head with the pipette to tighten it, but such operation will lead to deformation of the suction head and affect the accuracy. In serious cases, it will damage the pipette, so such operation should be avoided. Rainin’s multi-channel pipette does not have an O-ring. With the suction head with front stop point, it can achieve ideal sealing only by pressing gently. It is really a blessing for users of multi-channel pipette.
3. Immersion angle and depth of suction head:
The immersion angle of the suction head shall be controlled within 20 degrees, and it is better to keep it vertical; The recommended immersion depth of suction head is as follows:
Pipette specification suction head immersion depth
2L and 10 L 1 mm
20L and 100 L 2-3 mm
200L and 1000 l 3-6 mm
5000 l and 10 ml 6-10 mm
4. Moistening and washing of suction head:
For normal temperature samples, moistening the suction head is helpful to improve the accuracy; However, for high-temperature or low-temperature samples, moistening the suction head will reduce the operation accuracy. Please pay special attention to it.
5. Suction speed:
The pipetting operation shall maintain a smooth and appropriate suction speed; Too fast liquid absorption speed is easy to cause the sample to enter the sleeve handle, resulting in damage to the piston and sealing ring and cross contamination of the sample.
[expert advice:]
1. Maintain correct posture during liquid transfer; Do not hold the pipette tightly at all times. Use the pipette with finger hook to help relieve hand fatigue; Change hands frequently if possible.
2. Regularly check the sealing condition of the pipette. Once the sealing aging or liquid leakage is found, the sealing ring must be replaced in time.
3. Calibrate the pipette 1-2 times a year (depending on the frequency of use).
4. Most pipettes should be coated with a layer of lubricating oil before use and after use for a period of time to maintain sealing; For rainin pipettes with conventional range, it also has ideal sealing performance without lubricating oil.
