Eppendorf Reference - Manual (Page 14)

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The serial number of the pipette is located on its control button.
8.1 Testing
Distilled water is dispensed from a pre-wetted tip into a tube and is then weighed.
Volumes 0.1 – 10 μL:
The test is performed with a highly sensitive analytic balance (resolution balance:
0.001 mg) by releasing the volume.
The bidistilled water, weighing vessel, pipette and pipette tip must all
be the same temperature!
To calculate the volume, divide the weight by the density of the water
(at 20 °C: 0.9982 mg/μL; mg/μL = g/mL).
Volumes > 10 – 2.500 μL:
For a volume of more than 10 μL, a balance with a resolution of 0.01 mg is
sufficient.
8.2 Alignment
8.2.1 When should alignment be carried out?
The pipettes in the Reference-Serie were tested during production in accordance
with the measurement conditions for water listed in Chapter 2.
In the case of doubts arising about the accuracy of the pipetted volume, the
following points should first be checked:
– Is the pipette leaking? (This is one possible reason for dispensed volumes
being too low; troubleshooting and solutions are contained in Chapter 7)
– What is the temperature of the sample? (In open tubes, water at room
temperature cools down due to evaporation.)
– What is the temperature of the pipette?
– What is the temperature of the air?
– Has mg been converted into μL?
– Does the sample have a different density to that of water?
– Is the pipetting speed too high?
8 Testing / Alignment
Eppendorf Reference® – Part A – Chapter 8