Manual

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Note:
For Research, adjustable-volume (variable), 500–5 000 µL and 1 – 10 mL: if the
tip is removed from the liquid too quickly, coaxial forces may push liquid out of
the tip. This may result in the pipetted volume being too low.
4.4 Dispensing liquid
– Hold the tip(s) at an angle against the inside wall of the tube/well of the
microtiter plate.
– Press down the control button (Fig. 2-1) slowly to the first stop (measuring
stroke) and wait until the liquid stops flowing.
– Press down the control button to the second stroke (blow-out) until the tip(s)
is/are completely empty.
– Hold down the control button and pull the tip(s) up the inner wall of the tube.
– Allow the control button to slide back slowly.
Tips are ejected by pressing the ejection button on the side of the pipette
(Fig. 2-3).
Do not lay down the pipette when a filled pipette tip is attached as
this may result in liquid entering the pipette!
4.5 Special notes
To guarantee precision and accuracy, we recommend pre-wetting all new tips by
aspirating and dispensing liquid two or three times before pipetting.
With the tip not in contact with the liquid, empty it completely on the inner wall of
the tube (via blow-out).
Explanation: why does the pipette tip have to be pre-wetted ?
To compensate for the properties of the liquid.
Wetting liquids (serum, detergent) form a thin film on the inner wall of the pipette
tip. When the first pipetting is carried out, the volume dispensed would thus be
too low.
When pipetting serum or high-viscosity solutions, wait a few seconds when
aspirating and dispensing liquid.
Research – Part A – Section 4
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