When conducting research on analysis and testing, a pipettor is generally used to measure a small amount or a small amount of liquid. Many people will ignore the correct use of the pipettor and some details of its operation, which will be described in detail in several aspects.
1. Range adjustment
When adjusting the range, if you want to adjust from a large volume to a small volume, you can turn the knob clockwise according to the normal adjustment method; but if you want to adjust from a small volume to a large volume, you can first turn the scale knob counterclockwise to exceed the scale of the range, and then call back to the set volume, so as to ensure the highest accuracy of the measurement.
During this process, never turn the button out of the range, otherwise, the internal mechanical device will be stuck and the pipettor will be damaged.
2. Assembly of the gun head
When putting a pipettor tip on a pipettor gun, many people will knock on the pipettor box a few times. The correct method is to vertically insert the pipettor (instrument) into the tip of the pipettor. If it is a multi-channel (such as 8 or 12) pipettor gun, you can align the first pipettor pipe with the first pipettor tip, then insert it obliquely, and shake it in the front-back direction to lock. The sign that the gun head is tight is slightly over the O-ring, and you can see the connection part forms a clear seal ring.
3. The method of pipetting
Before pipetting, make sure that the pipettor, tip, and liquid are at the same temperature. When aspirating liquid, the pipettor is kept upright and the tip of the pipettor is inserted 2-3 mm below the liquid surface. Before sucking liquid, you can suck the liquid a few times to wet the suction nozzle (especially when you want to suck a viscous or different density of water). At this time, two pipetting methods can be used.
One is the forward pipetting method. Use your thumb to press the button to the first stop, and then slowly release the button to return to the original point (aspirate a fixed volume of liquid). Then press the button to the first stop point to discharge the liquid, stop for a while and continue to press the button to the second stop point to blow out the remaining liquid. Finally, release the button.
The second is the reverse pipetting method. This method is generally used to transfer high-viscosity liquids, biologically active liquids, liquids that are easy to foam, or very small amounts of liquids.
The principle is to inhale more than the set range of liquid first, and do not need to blow out the residual liquid when transferring the liquid. First press the button to the second stop point, slowly release the button to the original point, after sucking up, lean against the container wall to flow excess liquid back to the container along the container wall.
Then press the button to the first stop point to discharge the liquid with the set range, continue to hold the button at this (do not press it down again), remove the tip of the residual liquid, discard it and suck it up. Leaning against the container wall to flow excess liquid back to the container along the container wall.
4. Pipettor placement
After use, you can hang it vertically on the pipettor holder, but be careful not to drop it. When there is liquid in the pipettor tip, do not place the pipettor horizontally or upside down to prevent the backflow of liquid from corroding the piston spring.
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