Dispensing:
1. Touch the tip end against the side wall of the
receiving vessel and press the plunger slowly, past
the
FIRST STOP
, to blowout (bottom of stroke.) Wait
1 second for 2–200 µL volumes, 1-2 seconds for
1000 µL and larger. (Longer for viscous solutions.)
2. Still holding the plunger, withdraw the tip, sliding it
along the wall of the vessel. Release the plunger.
3. Press the tip ejector button lightly to discard the
tip. Use a new tip for each sample to prevent carry-
over. Repeat for the next pipetting cycle.
Pipetting Guidelines
Pipet-Lite pipettes incorporate several new features
which enhance pipetting consistency. You should
also maintain:
1. Consistent pickup and dispense rhythm.
2. Consistent speed and smoothness when pipetting.
3. Consistent pressure on the plunger button at the
FIRST STOP
.
4. Consistent immersion depth. See table on page 4.
5. Pipette vertically, or within 20° of vertical.
6. Don’t invert or lay the pipette flat with liquid in
the tip.
Pre-Rinsing Recommended
Some solutions may leave a film on the inside tip wall.
This film remains relatively constant in successive
pipettings with the same tip, so excellent precision
can be obtained by refilling the tip and using the
refilled volume as the sample. Successive samples
from this same tip will exhibit good reproducibility.
Reverse Mode Pipetting
Another way of reducing error due to film retention,
especially useful for more viscous liquids, is reverse
mode pipetting. The operating sequence is reversed:
1. Mount a disposable tip on the pipette shaft.
2. Press the pushbutton fully to the
SECOND STOP
.
3. Immerse the tip in liquid and allow the button to
return slowly to the fully
UP
position. Wait a
moment for the liquid column to reach equilibrium
in the tip.
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