WPI Nanoliter 2000, Instruction Manual

Page: 13 / 24

Nanoliter 2000
World Precision Instruments 9
3. Eject the liquid into the micropipette and slowly withdraw the MicroFil
needle as the liquid fills the micropipette.
Front Filling
“Front filling” is the term to describe filling a micropipette through the
small, pulled front end of the pipette. Front filling is achieved by creating
a vacuum at the back end of the pipette that pulls the filling liquid into
the micropipette. Once the microliter is installed on the
Nanoliter 2000 ,
it is possible to front fill. Front filling is advantageous for small volumes
or expensive samples. Because of the small opening in the front, it is not
preferred for bulk filling of large volumes.
Typical Technique
The technique described below is a typical process for filling a micropipette
with a small volume for microinjection.
1. Backfill the micropipette with mineral oil.
2. Use the
Nanoliter 2000 controller to eject the plunger from the home
position. This is necessary in order to allow the plunger to move
backwards to create a vacuum for front filling.
3. Fig. 5 and Fig. 6 show the assembly of the micropipette to the Nanoliter
2000 .
4. Once the micropipette is installed, submerge the micropipette tip into
the sample.
5. Press the Fill button on the Nanoliter 2000 controller to pull the sample
into the tip of the micropipette.
Injecting
Injection aliquot volumes are determined by the position of the DIP
switches, located on the right side of the
Nanoliter 2000 . DIP switches #1–4
control the aliquot volume ( Fig. 6 ). DIP switch #5 selects the fast injection
rate and fill rates. See “Setting the Aliquot Volume and Injection Speed” on
page 10.
Fig. 6 –The DIP switches, located on the right side of the control unit, determine
the injection volumes. See Table 1.