The instructions for suction and discharge of serological pipettes are worth studying!
A serological pipette is a measuring device used to accurately pipette a certain volume of solution. As a measuring instrument, it is only used to measure the volume of the solution it releases. It is a slender glass tube with a bulge in the middle. The lower end is beak-shaped, and a marking line is engraved on the neck of the upper end, which is a sign of the exact volume removed.
Before using the serological pipette, select the range and pipette type, and then check the pipette mark, accuracy level, scale mark position, integrity, etc., and wipe the outer surface with filter paper.
Pinch the upper end of the pipette with the thumb and middle finger of the right hand (left hand), and insert the lower mouth of the tube into the solution to be sucked. The insertion should not be too shallow or too deep, generally 10-20mm, too shallow will cause suction. , Suction the solution into the ear-washing bulb to contaminate the solution, if it is too deep, the solution will adhere to the outside of the tube too much. Take the ear-washing ball in the left hand (right hand), connect it to the upper mouth of the tube and slowly inhale the solution, first inhale about 1/3 of the capacity of the tube, hold the mouth of the tube with the index finger of the right hand (left hand), take it out and hold it horizontally. Rotate the tube so that the solution touches the part above the scale to replace the water on the inner wall, then release the solution from the lower mouth of the tube and discard it and place it in the waste liquid beaker. Above 10-20mm, immediately press the nozzle with the index finger of the right hand (left hand).
Dispensing of serological pipettes:
If the container for the solution is a conical flask, the conical flask should be tilted 30°, the pipette should be upright, the lower end of the pipe should be close to the inner wall of the conical flask, loosen the index finger slightly, and let the solution flow down slowly and naturally along the bottle wall. After the tip of the tube touches the inner wall of the bottle for about 10-15s, the pipette is removed, and a small amount of solution remaining at the end of the tube cannot be forced out by external force, because the volume of the solution retained at the end has been considered during calibration.
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