1Single channel pipetteDaily maintenance: Extend lifespan and ensure long-term accuracy
1. Cleaning and disinfection
Surface cleaning: After daily experiments, wipe the outer shell with a non-woven fabric soaked in 70% isopropanol, focusing on cleaning the button gaps and suction nozzle interfaces. Laboratories with biosafety level 2 or above must be wiped with a 1% sodium hypochlorite solution for at least 3 minutes.
Residual treatment of suction head: After using a dedicated ejector to discard the suction head, immediately clean the inner wall of the cone sleeve with absorbent paper. If liquid seeps in, the lower sleeve needs to be disassembled, the piston assembly rinsed with distilled water, and allowed to air dry naturally.
2. Lubrication management
High frequency usage scenario: After every 2000 operations, apply a small amount of specialized silicone grease to the piston and sealing ring to reduce friction and wear. Avoid using regular lubricants to prevent corrosion of rubber components.
Low frequency usage scenario: Conventional range pipettes can be lubrication free, but the piston movement resistance needs to be checked quarterly. If there is any jamming, timely lubrication is required.
3. Sealing test
Quarterly testing: Calibration device verification using gravity method: Transfer 200 μ L of ultrapure water 10 times at 20 ℃ environment, and the standard deviation of weighing should be ≤ 0.03mg. If the data fluctuates>0.05mg, the sealing ring needs to be replaced.
Daily inspection: After absorbing the liquid, suspend it vertically for a few seconds and observe if the liquid level drops. If the decrease is significant, check if the suction head is installed properly or if the sealing ring is aging.
4. Range adjustment and storage
When not in use for a long time: Adjust the range to the maximum scale to keep the spring in a relaxed state and avoid elastic fatigue.
Transportation protection: When moving equipment, it must be packed in the original protective box to avoid collision and displacement of the range adjustment knob.
IISingle channel pipetteOperation standard: Details determine success or failure, avoiding human error
1. Principle of Range Selection
The transfer volume should be within 35% -100% of the suction range, and avoid using a large range pipette to transfer small volumes of liquid. For example, when transferring 10 μ L of liquid, a 10 μ L range pipette should be selected instead of a 100 μ L range pipette adjusted to 10 μ L.
2. Tips for installing suction heads
Insert the pipette vertically into the suction head, rotate it left and right half a turn, and tighten it to avoid deformation caused by repeated impact on the suction head. Some multi-channel pipettes are equipped with O-rings and suction tips with stops, which can be lightly pressed to achieve the desired sealing effect.
3. Key points for liquid absorption and discharge
Liquid suction: Dip the suction head vertically into the liquid surface by 1-2mm (micro pipette) or 6-10mm (large range pipette), slowly release the button to the first gear to avoid bubble formation.
Drain: Contact the container wall at a 45 ° angle, first press to the first level to drain most of the liquid, and then press to the second level to drain any remaining liquid. For viscous liquids, the pause time should be extended to 3 seconds.
4. Avoid temperature influence
The temperature of the pipette should be consistent with the liquid temperature (such as 25 ℃± 1 ℃) to avoid heating the pipette with hand temperature, which may cause internal air expansion. When removing liquids from an ice bath or high-temperature environment, it is necessary to pre balance the temperature.
5. Specification for removing suction tips
Use a dedicated ejector to discard the suction head to avoid contamination caused by residual liquid splashing inside the suction head. If the suction head has difficulty popping out, check if the ejector spring is fatigued or if the connecting rod is stuck, and clean or replace the components in a timely manner.