Table of Contents
Advertisement
Pipetting Guidelines & Precautions
Consistency in all aspects of pipetting procedure will con-
tribute significantly to optimum reproducibility. Use a:
1. Consistent pickup/dispense rhythm while pipetting.
2. Consistent speed and smoothness when you press
and release the pushbutton.
3. Consistent pushbutton pressure at the
4. Consistent immersion depth.
5. Minimal angle (< 20° from vertical).
If an air bubble enters the tip, dispense the sample to the
original vessel, check tip immersion depth, and pipette
more slowly. If an air bubble appears a second time, dis-
card the tip and use a new one.
Prevent liquids from being drawn into the Pipetman shaft
by taking the following precautions:
1. Never invert or lay Pipetman down if liquid is in the tip.
2. Pipette slowly, holding Pipetman < 20° from vertical.
3. Use Rainin aerosol-resistant tips, with an internal filter
which acts as a barrier to aerosols and liquids.
4. For Pipetman Models F-1001 to F-10ML, use the
special filters supplied.
Temperature Considerations
You can measure warm or cold liquids with good preci-
sion by using a consistent pipetting rhythm. A consistent
rhythm will help to minimize any differences in heating or
cooling effects within the pipette. Use a new disposable
tip each time for best accuracy and precision when mea-
suring samples with temperatures greatly different from
ambient, and do not pre-rinse.
As with any air-displacement pipette, best results will be
obtained if there is no delay between picking up the sam-
ple and dispensing it.
Acids and Corrosives
When pipetting concentrated acids or highly corrosive
solutions it is recommended that Pipetman be disassem-
bled after use and the piston, shaft, and seal assemblies
inspected, cleaned if necessary, and reassembled.
Extensive contact with corrosive fumes may corrode the
piston. This will inevitably result in premature seal wear
and may require refinishing or replacement of the piston.
Exposure of internal Pipetman components to corrosive
fumes can be reduced by using Rainin aerosol-resistant
tips: an internal filter acts as an aerosol barrier.
6
.
FIRST STOP
Advertisement
Table of Contents
