Here are the typical steps to measure liquid volume using a serological pipette:
1. Attach a rubber bulb or pipette pump to the top of the serological pipette.
2. Immerse the tip of the pipette into the liquid to be measured.
3. Gently squeeze and release the bulb to draw liquid up into the pipette. Draw the liquid slightly above the desired volume mark.
4. Remove the pipette from the liquid and hold it vertically with the tip pointing upwards.
5. Slowly release pressure on the bulb to allow the excess liquid to drain back down until the bottom of the meniscus is aligned with the volume mark.
6. The line at the bottom of the curved meniscus indicates the volume measurement. Read this against the graduations printed on the pipette.
7. The thin tip and fine graduations allow very precise volume measurement, usually to within 0.02 mL or less.
8. For accuracy, keep the pipette vertical while reading the volume and read it at eye level.
9. Dispense the measured volume by carefully squeezing the bulb. Serological pipettes allow very accurate transfer of the measured liquid volume.
10. Dispose of the plastic serological pipette after one use to avoid contamination.
