Proper Use Of Pipette
1. Adjusting range
When adjusting the measuring range, if you want to adjust from large volume to small volume, you can rotate the knob anticlockwise according to the normal adjustment method; but if you want to adjust from small volume to large volume, you can first rotate the scale knob clockwise to the scale beyond the measuring range, and then callback to the set volume, so as to ensure the highest accuracy of measurement. In this process, do not turn the button out of the range, otherwise, the internal mechanism will be stuck and the pipette will be damaged.
2. Assemble the pipette head (suction nozzle)
When the pipette head is put on the pipette, the correct method is to insert the pipette (device) vertically into the pipette head and turn it slightly to the left and right with a little force to make it tightly combined. If it is a multi-channel (such as 8 or 12 channels) pipette, the first channel of the pipette can be aimed at the first pipette head, then it can be inserted obliquely, and it can be clamped by shaking forward and backward. The mark of the pipette head clamping is slightly more than the O-ring, and the connection part can be seen to form a clear sealing ring.
3. Method of liquid transfer
Before liquid transfer, make sure that the pipette, pipette head, and liquid are at the same temperature. When sucking the liquid, keep the pipette vertical and insert the pipette head 2-3mm below the liquid level. Before sucking the liquid, you can first suck and put liquid several times to wet the sucking nozzle (especially when you want to suck liquid with viscosity or density different from water). At this time, two methods of liquid transfer can be adopted.
One is forward pipetting. Press the button with your thumb to the first stop, and then slowly release the button back to the origin. Then press the button to the first stop point to discharge the liquid, and then press the button to the second stop point to blow out the residual liquid. Finally, release the button.
The other is reverse pipetting. This method is generally used to transfer high viscosity liquid, biological active liquid, easily foaming liquid or a very small amount of liquid. Its principle is to first inhale more than the set range of liquid, and when transferring the liquid, there is no need to blow out the residual liquid. First, press the button to the second stop point, and slowly release the button to the origin. Then press the button to the first stop point to discharge the set range of liquid, keep holding the button at the first stop point (never press down again), remove the pipette head with residual liquid and discard it.
4. Correct placement of pipette
After use, it can be hung vertically on the pipette rack, but be careful not to fall down. When there is liquid in the tip of the pipette, do not place the pipette horizontally or upside down, so as to avoid the backflow of liquid corroding the piston spring.