Dual-Superfusion Slice Chamber Insert

 

It is not only a new product, but a unique, worldwide patented idea to support longer surviving of brain slices. This is a brand new improvement of slice chambers for electrophysiological recordings and/or in vitro imaging developed by Prof. Dr. Norbert Hajos, D.Sc. (email: hajos@koki.hu). The Dual-superfusion Slice Chamber Insert is recommended for all types of slice recordings, but it is indispensable for those investigations, where oxygen is a limiting factor of neuronal function, e.g. network oscillations (Hajos et al., European Journal of Neuroscience, Vol. 29, pp. 319-327, 2009).

 

 

 

 

 

Dual-superfusion of submerged slices increases the vitality of cells, since e.g. oxygen as well as other materials from both sides can freely and more effectively diffuse into the thick slices. In the most widely used slice chambers, where the slices are sitting on a glass cover slip, the oxygenation and the drug diffusion is achieved only from one side.

 

 

We invented a chamber insert where slices are sitting on a mesh and the shape of the insert supports laminar flow around the submerged slices ensuring the better oxygenation of slices. The mesh divides the chamber into two parts. Both the upper (above the mesh), and the lower (below the mesh) parts of the chamber have got 2 mm of height. By using this type of chamber design, the flow rate of the superfused solutions could be kept as low as 3-5 ml/min, yet the oxygenation of the tissue could be maximally maintained.

 

Dual-superfusion Slice Chamber Insert is 20 mm in outer diameter. We have chosen this diameter, because this way our product is compatible with the most popular brain slice chambers on the market. The mechanical drawing of the plexiglas insert is available for download. In the future we will introduce bigger meshes in the same 20 mm outer diameter to use human brain slices. The requirements for your given brain slice chamber to use Dual-superfusion Slice Chamber Insert are:

- the diameter of the internal middle hole must be bigger than 20 mm

- the effective depth of the internal middle hole should be approximately 5 mm or more

 

The working (meshed) area of the stainless steel mesh is 7.2 by 7.2 mm.

 

A description how to maintain slices in interface conditions is available for download.

 

A product leaflet of Dual-Superfusion Slice Chamber Insert is available for download.

 

A Frequently Asked Questions file about Dual-Superfusion Slice Chamber Insert is available for download.

 

 

Stainless steel mesh:

 

        Click on the picture to get it in full size

 

One piece of plexiglas insert:

 

        Click on the picture to get it in full size

 

Plexiglas inserts with stainless steel mesh:

 

        Click on the picture to get it in full size

 

 

Tips

 

Based on the experience obtained in Prof. Dr. Norbert Hajos' laboratory (Hajos et al., 2009, see above), the temperature and the oxygenation of brain slices in Dual-Superfusion Slice Chamber Insert could be controlled in two ways. Either the experiments should be done at room temperature, then only the flow rate of aCSF (Artificial CerebroSpinal Fluid) has to be set equivalently below and above the slices (e.g. using peristaltic pumps with at least three channels - two inlets and one outlet). Or, in the case, when experiments are desired to perform at higher temperature, then not only the flow rate but the temperature, as well, should be maintained as equivalent as possible below and above the slices. To achieve this, a Dual-channel In-line Solution Heater is recommended to use, where the temperature of two inlets is controlled in a single heater head to ensure the same temperature.

 

If you want to use the Dual-Superfusion Slice Chamber Insert in optimal conditions, the temperature of the two independent solution flows should be controlled. For this purpose any kind of 2-channel in-line solution heater, and a compatible temperature controller should also be used. We recommend to use the appropriate products of  Supertech Instruments. They are Dual-channel In-line Solution Heater and the compatible Physiological - Biological Temperature Controller TMP-5x. They are the optimal choice, because they are matched together and optimized for dual-superfusion surviving method.

 

On the surface of the stainless steel mesh the effects of some unwanted electrochemical changes can be observed after 3 month of usage. If you realize such a disturbing effect, please change the mesh in order to provide the optimal living conditions of your slices.

 

Some sterilizing gases used in the medical routine destroy the material of the plexiglas inserts chemically. Please take this aspect into account.

 

We offer the complete assembly "Plexiglas inserts with stainless steel mesh", and its parts independently, too. The reason, why we offer the parts, that there are many of our customers who regularly cleans the mesh, but the result of cleaning the plexiglas inserts is not sure, they are simply changed. The new plexiglas parts can be assembled together with the old, but disinfected mesh. Similarly, the mesh can also be changed any time.