Instruction manual

2 World Precision Instruments
amount of time that the injection pressure is applied to the output port. Time intervals can
range from 10 seconds down to 10ms or less, depending on the eject pressure setting. The
injection pressure interval can be triggered manually on the front panel, by foot switch or
by a computer controlled TTL pulse. A 5V mon i tor output provides a logic-level pulse for
your computer or other mon i tor ing device.
The PicoPumps are designed to inject very small quantities of fl uids, such as drugs,
into cells or small organelles. Pressure injection is an especially useful alternative to
electroionophoresis, since it does not mandate the use of charged ions. Two different
positive pressures may be applied–one for ejection at high pressure and a second, lower
pressure to prevent back fi lling of the pipette by capillary action. Vacuum may also be
applied on a separate channel to hold cells or small objects and to load pipettes from the
tip. Therefore, cells may be held by vacuum and simultaneously injected using pressure.
PV820
Like the PV830, the PV820 offers separate regulated hold and ejection pres sures with
a pre ci sion timing circuit that switches from eject pressure to hold pres sure au to mat i cal-
ly. Al though reg u lat ed vac u um is not pro vid ed in this mod el, suction can be pro vid ed by
con nect ing a pre-regulated vac u um source to the vac u um port on the rear pan el. Suc tion
is then available through the pres sure ports.
PV830
On the PV830, eject pressure, hold pressure and vacuum are all available, controlled
by separate reg u la tors on the front panel. Eject pressure supplies a high-pressure pulse
for injecting fl uid. Hold pressure, which is not suffi cient to cause fl uid ejection, is used
to prevent front fi lling of the pipette by capillary action when not injecting. Pressure in
the injection pipette is au to mat i cal ly switched between Eject and Hold pressure by a
precision timing circuit that controls a solenoid valve. Vacuum is regulated the same way,
by a 20-turn knob on the front panel. The vacuum port may be switched from regulated
vacuum to at mo sphere by using a switch on the front panel. Vacuum may also be routed
to the eject port.
Notes and Warnings
!
WARNING: SECURE THE PIPETTE FIRMLY IN THE HOLDER. WHEN HIGH
PRESSURE IS APPLIED, A LOOSE PIPETTE CAN BE EJECTED FORCEFULLY.
DO NOT APPLY PRESSURES IN EXCESS OF 150PSI (1000KPA).
!
WARNING: USE DRY AIR, NITROGEN OR OTHER INERT GASES ONLY. DO
NOT USE OXYGEN.
!
WARNING: THIS INSTRUMENT IS FOR INVESTIGATIONAL USE ONLY IN
ANIMALS OR OTHER TESTS THAT DO NOT INVOLVE HUMAN SUBJECTS.