WPI PV850, Инструкция по эксплуатации

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PV850
World Precision Instruments 17
ass r at ts t o o u t rou t t Silanization decreases the surface
t ns on an a o s t u to o s oot t rou t t or s ar r asons
on t r o n us o a a ar t an nt rna a nt So o t an
papers on the art of silanization are listed in the bibliography.
Calibrating Volume by Measuring Droplet
For ejected volumes greater than 1 nL, visual inspection using a microscope can be
an a urat au o o u s n u s os ts a ro o u on t t o t
micropipette. The volume of this drop may be calculated by measuring the radius of
the drop and assuming the drop to be spherical. Fig. 26 may be helpful in determining
the volume for a given radius. See “Appendix A: Droplet Volume” on page 23 for a
comparison of spherical and cubical volumes.
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. 26—(Left) The volume of a droplet increases as the diameter increases. See “Appendix A:
Droplet Volume” on page 23.
Fig. 27—(Right) WPI’s MicroFil is helpful in backfilling glass pipette tips. The MicroFil’s tip is
thin and very flexible.
o o n ta s us u or on rt n t n ff r nt un ts o o u
Cubic Measure 1 cm
3
1 mm
3
100 µm
3
10 µm
3
1 µm
3
Volume 1 mL 1 µL 1 nL (
-12
) (
-15
)
or t o u s ss t an n sua ns t on n a r ro s to u t u
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.
So t s t s s u to r a o t a u ous u a a on t outs s an o
the micropipette. This creepage may be decreased by silanizing the outside of the pipette.
TIP : Precise assays of ejected volume may also be obtained through various
radioisotopic methods. See the bibliography for further information.
s t t on o t ro tt t a not ur n t a at on o t
r ssur u s s t on a nat nsur n t at t ro tt s
r s at n t o r an t at t o r s r a an u ator