In depth understanding of internal volume pipettes

The volume of all the liquid in the pipette is consistent with the scale. The usual pipette scale marks the volume of liquid "flowing out". This pipette is suitable for solutions with low viscosity. For the liquid with high viscosity, the scale marked on the tube is the total volume of the tube, because there is a lot of residue on the inner wall of the pipe. Generally, the inner wall of the pipette should be washed with solvent after suction, so the volume marked by the scale of the content pipette is slightly smaller than that of the commonly used "external volume" type.
The content pipette is a common pipette. The difference is that the former is metering operation while the latter is metering out. The correction value needs to be recorded and added to the operation. It is usually used for sampling of viscous samples. After sampling, clean and transfer with appropriate amount of solvent.
Difference between content pipette and common pipette
Common pipette: the normal pipette scale marks the volume of liquid "flowing out". This pipette is suitable for solutions with low viscosity.
Content pipette: the content pipette is used to transfer viscous liquid. It belongs to metering pipette. It needs to be washed with solvent for many times, and the washing solution is put into a volumetric flask, and then diluted to the scale with solvent for sample preparation. For example, if the mark scale is 2ml, then draw the liquid to the scale volume is exactly 2ml, and then rinse the liquid adsorbed on the pipe wall with solvent after discharge.
The volume of all the liquid in the pipette is consistent with the scale. For the liquid with high viscosity, the scale marked on the tube is the total volume of the tube, because there is a lot of residue on the inner wall of the pipe.
The pipette also has a big belly. The main differences are: first, it can be flushed; second, theoretically, when aspirating, it should be just sucked to the scale line. If it is sucked above the scale line, it is not allowed to put it on the scale line again. Generally, the inner wall of pipette should be washed with solvent after suction. Therefore, the volume indicated by the scale of the content pipette is slightly smaller than that of the commonly used "external volume" type.
Content pipette usage
Content pipette should only be used in some industries, such as blood test; the pipette itself has low accuracy. Some netizens said: chemical analysis of the capacity vessels should be able to use volumetric flasks, high viscosity things, pipette suction is also very difficult, it is better to simply weigh the weight is convenient, the Pharmacopoeia of this kind to seek truth should be changed.
The content pipette belongs to the metering pipette, but we usually use the metering pipette. When using, first measure according to the scale, and then wash all the liquid on the inner wall with water into the container, which is specially used for the detection of viscous liquid. In general, syrup and other viscous liquid detection seems to be used, Paclitaxel injection to use internal volume pipette. Some glassware manufacturers can make them, but they usually have to order them because of the small amount of them.

TIANTAI BIOLIFE PLASTIC Co., Ltd.