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Fig.1:
Patch pipette moved by a Nanomotor

Fig.
2: A patch clamp head including an additional D.O.F.

Fig.
3: Sketch of the patch clamp head
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Patch Clamp Manipulators, Small, cartesian, robust
and in closed loop:
For Patch Clamp Manipulation a microscope is combined with manipulators.
Since these manipulators are quite big the mechanical path from patch pipette
to a cell can be about one meter, causing drift and oscillations. A clever
setup is necessary when you like to have more than one or two manipulators
pointing at the same position:

Conventional bulky patch clamp manipulator setup (gray) and a
Nanorobotics manipulator in the center, scaled 1:1 into the image.
A normal microscope with four manipulators
for cell manipulation is shown in the background of the upper
picture. An area of about two square meter is filled with this
equipment. The manipulators are fixed on the ground, not at the
sample stage. So sample and manipulator cam move relative to each
other. The small picture on top of it shows one NMT xyz-manipulator,
scaled into this setup. This very compact device can replace one
of the four big ones completely - with a much higher precision.
And some of these manipulators can be fixed directly at the sample
stage with a very short mechanical path to the sample. This manipulator
is by far not the samllest we can deliver. It includes position
sensors for repeatable operation and a preamplifier is also assembled
at the top end.
A Nanomotor
inside of a Patch Clamp Head:
Even inside of a Patch Clamp Head there is
space enough for a Nanomotor, see Fig. 2 and 3 and the following
image:

A "Small" Nanomotor inside the patch pipette
This additional degree of freedom allows to
measure the mobility of molecules that leave a single cell: High
resolution patch capacitance measurements of membrane fusion in
combination with amperometric detection of released molecules.
The amperometric detector is placed inside of the patch pipette.
Details are described in the paper Electrochemical
methods for Neuroscience.
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