ddk2 at case.edu wrote:
> Greetings everyone. First post here and I need some suggestions. What
> do you guys use for a manipulator in your slice rigs? I currently have
> a burleigh pcs5000 but it gives too much drift and I am not happy. I
> want to buy another manipulator and am curious to others thoughts.
>> thanks,
> dave
Akk!
I truly, truly hate those damn Burleigh piezo manipulators. Used them
for several years, they ALL drift, we had to send almost every one of
ours back to the factory to deal with electrical or mechanical problems
(Burleigh admitted they were faulty and replaced parts) and even when
they are working "properly" they have extremely limited travel distance
in fine mode. And in coarse mode (i.e., with your hand on the knob),
the pipette wiggles all over the place. If my hand was that steady,
well, I wouldn't need a micromanipulator, now would I? Basically, I
think they suck, and have never understood why anyone would want a
piezo manipulator for patching cells, given the known nonlinearities
and drift associated with piezo materials. I was actually lectured by a
rep from Burleigh once about how my drift problems were all my fault,
because I hadn't followed their prescribed "cable handling" procedure
(i.e., you have to suspend the cables vertically directly *above* the
manipulator to reduce strain in all directions - I am not joking, they
actually have a technical report that recommends this preposterous
"method", including a diagram, as the best way to keep the manipulators
from drifting).
Anyway, I use Siskiyou Design Instruments (SD-Instruments) mechanical
screw-drive manipulators. You may not have heard of the company,
they're relatively small and relatively new. I believe the engineering
staff may have originally come from Newport. They make manipulators
that are similar in many respects to both Newport and Luigs & Neumann,
but when i was comparing prices several years ago, the SD ones were
considerably cheaper. I have been 100% happy with them. No drift,
several mm of travel distance, adjustable speed, and modular so that
you can take them apart and reconfigure them for different setups
(e.g., right vs left-handed use, etc). We have had 1 problem, which was
that one of the controller buttons was sticky on one of our
manipulators. I called up SD and the *president* of the company
answered the phone (this was in 2001, so they've probably got
receptionists by now). He instantly agreed to send me a replacement
controller.
In addition to manipulators, I use SD for all of the rig
"architecture": e.g., microscope XY translator, specimen stage, coarse
manipulators, and all other building blocks. In fact, these parts all
come essentially as building blocks, so they give a lot of flexibility
in how you set things up.
The most important consideration in all of this is probably mechanical
stability. The stability we can get with the SD equipment is sufficient
for us to routinely make dual recordings from synaptically-coupled
hippocampal neurons that last over an hour.
Here's the SD website:
http://www.sd-instruments.com/
and here's the type of manipulators we use:
http://www.sd-instruments.com/MX7630.htm
And by the way, I have no affiliation with, nor commercial interest, in
SD-Instruments.
Cheers,
Matt