Infrared Patchclamp

In the following we would like to introduce the 240 XY and the 380 FM Workstations, two different infrared patch-clamp set-ups so as to demonstrate the possibility of different combinations and their according advantages.
All workstations and set-ups are universally compatible to all know microscopes and are very easy to handle. These set-ups can additionally be upgraded by various specific components such as the Dodt Gradient Contrast and the Infrared-Guided Photostimulation System also later explained in more detail.

240 XY Workstation

This workstation is set-up with a ring slot for a possible integration of up to five LN Mini 25 Units. The microscope can be manoeuvred individually (manually / motorized) in three dimensions independent to the experiment enabling the combination of patch-clamp measurements, fluorescent applications and infrared guided photostimulation. The shifting table has teflon coated surfaces and is mechanically damped from the base plate preventing any undesired vibrations.
As an example, the workstation might be set-up as follows:

• 240XY shifting table for microscope
• LN Mini 25 Unit MRE right side
• LN Mini 25 Unit MLE left side
• LN Mini 25 Unit B3ES 3 axis chamber manipulator
• 3 steel columns
• Headstage holders

This assembly just shows one example of many different possibilities. For more information please contact Luigs & Neumann.

After 10 years of research and development Luigs & Neumann has come up with a completely new and compatible system that is very easy to use. All anticipated aspects such as grounding, possible drift etc, have been taken into account and dealt with during the development.
The 380 FM workstation allows the combination of electrophysiological experiments with confocal applications, enabling to position up to 8 electrodes e.g. patch electrodes fluorescents / injection and stimulation electrodes around the chamber. These electrodes can be manoeuvred individually and independently from each other.
The microscope is mounted and fixed on four solid steel columns preventing any kind of vibration. The shifting table 380 FM enables to move the chamber simultaneously with the electrodes micron-exact. The very stable and solid Bridge 500 can carry heavy microscopes including additional components such as the Dodt Gradient Contrast and the Infrared-Guided Photostimulation System and hold different Slice Chambers for heating/ non heating or cover slips/ Nunc or Falcon dishes.
As an example, the workstation might be set-up as follows:

• 380FM shifting table for microscope
• LN Mini 25 Units right and left side (MRE/MLE)
• 3 steel columns
• Bridge 500
• Headstage holders

This assembly just shows one example of many different possibilities. For more information please contact us.

380 FM Workstation with the Zeiss Axioskop

380 FM Workstation with Olympus BX51 WI

Dodt Gradient Contrast (DGC)

This contrast system was developed in response to increasing demands in microscopy by Mr Dodt (MPI München). It enables to visualize the structures in sliced tissue.
Specific adjusting of the contrast enables various structures (horizontal or vertical) to be highlighted.
The Contrast is mounted between the microscope stand and the lamp housing. Since absolutely no contrast procedure is provided by the manufacturer, an independent and for all microscopes adaptable system has been developed.
In the same way it is also for the first time possible to obtain fluorescence and infra-red pictures simultaneously without any great effort.

Technical Data

• Contrast method as from Mr. H.-U. Dodt
• Developed for infra-red microscopy
• Available for all erect / inverse microscopy
• Adjustments can also be set motorized
• Independent to constitution and structure
  of the base of the chamber (thickness / material)

Infrared-Guided Photostimulation

The infrared-guided photostimulation system allows one to stimulate neurons or parts of neurons in brain slices under visual control. The neurons are visualized by infrared video-microscopy in brain slices superfused with caged glutamate (0.2 - 1 mM) in Krebs-Ringer solution. The caged glutamate is per se inactive, but the cage can be opened by irradiation with UV-light. This results in the release of active glutamate which causes depolarisation of the neuron on which the UV-light spot is directed.

The infrared-guided photostimulation system can be used for two kinds of experiments:

1. Investigation of neurontransmitter sensitivity of the neuron recorded. For this kind of experiment, the neuron is isolated from synaptic input with TTX and the UV-light spot is directed on the soma or various parts of the apical dendrite. The response recorded indicates the sensitivity of the neuronal part onto which the caged neurotransmitter is released.

2. Investigation of neuronal circuits. Without the addition of TTX, many neurons can be scanned and stimulated and synaptic connections to the neuron recorded will be revealed by a synaptic potential following the UV-stimulation.

Technical Data

• HBO 100W Housing
• 3 different neutral filter
• shutter + control
• fibreglass adjustment unit
• manipulator allows to adjust the spot in the centre of the field of view
• long fused silica fibre

Not Included

• epifluorescence condenser
• dichroic beamsplitter with cube