Micropipette is an indispensable precision instrument in the laboratory, used to accurately transfer small volumes of liquid. The following are the correct methods and precautions for using micropipette:
Tip installation:
For single-channel pipettes, insert the end of the pipette vertically into the tip, press lightly and turn slightly left and right to tighten.
For multi-channel pipettes, align the first channel of the pipette with the first tip, insert it at an angle, and rock it back and forth slightly to tighten.
Range setting:
Select an appropriate measuring range and avoid turning the adjustment knob outside the measuring range to avoid damaging the mechanical device inside the pipette.
The measurement range is selected between 35% and 100% of the full scale to ensure better accuracy and repeatability.
Aspiration and discharge:
When aspirating liquid, press the pipette button to the first gear and slowly aspirate the liquid to avoid liquid entering too quickly and causing back suction.
When dispensing liquid, press close to the wall of the container, first press to the first gear, pause briefly, and then press to the second gear to drain the remaining liquid.
Tip immersion depth and angle:
Immersing the tip at the proper depth improves accuracy. Don't dip too deep or too shallow.
When holding the pipette, keep it no more than 20° from vertical when aspirating or discharging liquids to improve accuracy.
Rinse:
Rinsing is a way to improve pipetting accuracy. After installing a new tip, rinse the tip 2 to 3 times with the same sample to keep the film constant and improve accuracy and repeatability.
Dispensing techniques:
When dispensing, touch the tip to the wall of the container for better consistency.
Slide the orifice end of the tip up along the wall of the container to remove any remaining liquid at the orifice end.
Correct placement:
After use, hang it vertically on the pipette holder, being careful not to fall.
Do not place the pipette horizontally or turn it upside down to prevent backflow of liquid and corrode the piston spring.