Instruction Manual – 15
Parameters for Checking the Pipetting Accuracy
The pipetting accuracy is influenced by factors such as:
tips used, characteristics of the pipetted liquid (density,
viscosity), and operating conditions (ambient temperature,
pressure).
To determine the accuracy error of the pipettor, the following
conditions should be met:
• Ambient temperature and temperature of the pipettor,
pipet tips, and liquid should be within the range of 20°C
to 25°C and stabilized during weighing within ±0.5°C.
• Measurements should be conducted using distilled water.
• Balance sensitivity should be suitable for the volume “V”
to be measured.
Volume Checked (V, μL)
Balance Sensitivity (mg)
0.1≤V≤10
0.001
10≤V≤100
0.01
100≤V≤1,000
0.1
V>1,000
0.1
• When calculating the liquid volume aspirated by
the pipettor, the conversion factor (Z) [μL/mg] for
distilled water or a liquid with comparable density
should be taken into account. Sample values of
conversion factors are given in the following table.
Temperature
(°C)
Pressure (kPa)
95.0
101.3
105.0
20
1.0028
1.0029
1.0029
21
1.0030
1.0031
1.0031
22
1.0032
1.0033
1.0033
23
1.0034
1.0035
1.0036
24
1.0037
1.0038
1.0038
25
1.0039
1.0040
1.0040
See ISO 8655 for the full table of conversion factors (Z).
NOTE:
Pipetting should be performed in accordance with
guidance described in Sections 7 and 8.