Well, basically micro-scissors have been demonstrated quite some years
ago with good success. I assume, that you will find useful info in
www.nikon.co.jp/.../technology_e/ mems_e/
As the technology is very straightforward for the "dumb knife", any
MEMS department in your university should be able to help using
silicon etch technology.
As a first try, I´d suggest to use a glass rod, heat it to the viscous
state an pull it "in the flame" apart until the two part separate. the
remaining ultrathin glass fibre may also suit your needs; I have seen
tips pulled out to about 5um "cutting radius"

Regards,

Erik
-------------------
> Hello everyone:
>
> I am only vaguely familiar with MEMS technology, but I have a
question
> about a possible application.  I am a veterinary embryologist and I
am
> trying to do "surgery" on embryos that are 100 to 150 microns in
> diameter (they are about 3 days post fertilization and have
> approximately 8 cells).  These embryos consist of a clump of very
> fragile cells surrounded by a very small fluid-filled space
> approximately 1 to 5 microns wide, and then enclosed in a soft but
tough
> shell approximately 10 microns thick.  I need to remove the clump of
> cells in the middle from their "shell" (the zona pellucida) without
> ripping them apart or bursting them.  This can be accomplished using
an
> enzyme to dissolve the shell, but the enzyme does some damage to the
> inner cells.  I have also tried using a laser fitted onto the
objective
> lens of a microscope to cut the shell, but the cells are so close to
the
> shell (touching in places) that I can't avoid overexposure to heat
from
> the laser.  I can rip a hole in the shell by holding the embryo with
> suction on one side applied to a fine glass pipette, while piercing
the
> other side with a glass needle; however, when I try to remove the
embryo
> by suctioning it out with a glass pipette, the cells get pulled
apart or
> ruptured.  I have come to the conclusion that I must cut the
embryo's
> shell with a blade (but can't find one small enough) or make a large
> hole, almost the diameter of the entire embryo, with a sharp
"biopsy"
> device while holding the embryo with my suction device (I have tried
> unsuccessfully to produce a biopsy tool using a glass pipette and a
> grinding wheel).  I have a set of micromanipulators that allow me to
> move two tools visualized through an inverted microscope.  The
problem
> is that I don't have the tools I need.  I am limited to working with
> glass rods or tubing and can pull it, cut it, and do some fairly
crude
> filing with a grinding wheel.  The embryo must remain in a liquid
medium
> during this procedure and is generally placed in a drop of this
medium
> in a dish filled with silicone oil.  Is there any way that MEMS
> technology could be used to solve my problem?
> Thank you very much for your time.
> Suzanne Walmsley
>
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>
>
Erik Jung
Fraunhofer-IZM
Gustav-Meyer-Allee 25
D-13355 Berlin