WPI PicoPump PV830, Инструкция по эксплуатации

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PV830 Pneumatic PicoPump
World Precision Instruments 13
1 pl
10 pl
100 pl
1 nl
10 nl
100 nl
1 µl
10 µm 100 µm 1 mm
Volume of a Spherical Droplet
V =
π
d
3
6
V
olume
Diameter
Fig. 11—(Left) The volume of a droplet increases as the diameter increases. See “Appendix”
on page 16.
Fig. 12—(Right) WPI’s MicroFil is helpful in backfilling glass pipette tips. Syringe filters
(available separately) help prevent clogged micropipette tips.
The following table is useful for converting between different units of volume.
Cubic Measure 1cm
3
1mm
3
(100µm)
3
(10µm)
3
1µm
3
Volume 1mL 1µL 1nL 1pL (10 -12 L) 1fL (10 -15 L)
For ejected volumes less than 1nL, visual inspection in air proves to be difficult due
to rapid evaporation. The same technique may be used though if the drop is kept
submerged under oil. Droplets may seem to disappear after emergence from the
tip. Sometimes this is due to creepage of the aqueous fluid back along the outside
shank of the micropipette. This creepage may be decreased by silanizing the outside
of the pipette. If it is desired to silanize only the outside of the pipette, the
PV830
may be used to good advantage by applying air flow through the pipette during the
silanization.
Precise assays of ejected volume may also be obtained through various
radioisotopic methods. See the bibliography for further information.
A slight deflection of the micropipette tip may be noticed during the application
of the pressure pulse. This deflection may be eliminated by ensuring that the
micropipette is firmly seated in the holder and that the holder is firmly held by a
manipulator.