Sutter Instrument P-97, Инструкции по эксплуатации

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Maximum usable values of DELAY will be dependent on glass dimensions but are expected to
be near 200 (100ms of delay).
3.5.2.6 PRESSURE Adjustment
The pressure setting controls the pressure of the cooling air delivered to the filament. The
higher the pressure, the shorter the pipette taper will be. Because thin walled glass cools
more rapidly than thick walled glass, the recommended values are
≤
300 for thin walled
tubing and 500 for thick walled or standard walled tubing. By varying PRESSURE around
these values, the user can control pipette tip length over a moderate range.
3.5.2.7 Filament Width
Further control over pipette tip length can be accomplished by varying filament width.
Longer tips can be formed by using wider filaments and conversely shorter tips can be
formed by using narrower filaments.
3.5.3 Patch Pipette Fabrication
Pipettes used for the electrophysiological recording technique of “patch clamping” are
characterized by a short, stubby shank and relatively large diameter tips (> 0.7 mm).
Programs that can fabricate a pipette with these characteristics generally differ from
programs for micropipettes in three ways:
The trip velocity is lower.
Hard pull is not activated (PULL = 0).
More than one heating cycle is used.
The P-97 can be used very effectively for this type of processing. The following general
information will familiarize you with the effect of adjusting each of the pull cycle parameters
in a typical patch pipette program. Following this general information are step-by-step
instructions intended to help you establish a stable program to pull patch type pipettes and
should be followed in the order described.
Consider the following sample patch program for 1.5 mm O.D. by 0.86 mm I.D. borosilicate
glass using a 2.5 x 2.5 mm Box filament:
HEAT PULL VELOCITY DELAY PRESSURE
Ramp 0 23 1 500
A program sequentially executes each line of code, then loops back to the start, and begins
again until the glass separates. A single line program such as this may execute two to four
times before the glass separates.
3.5.3.1 HEAT
The actual HEAT value used should be sufficiently high to allow the glass to melt in the first
cycle in 5 to 15 seconds. Using a higher HEAT that melts the glass in less than 5 seconds will
cause no problem in the first heating cycle, but may heat the glass so much in subsequent
heating cycles, that the air cooling will be less effective.
P-97 FLAMING/BROWN MICROPIPETTE PULLER OPERATION MANUAL – REV. 2.43 - DOM (20161118)