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 coverslip, 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 we wanted to make our product compatible with the most popular LN Insert Type A. The mechanical drawing of the plexiglass insert is available for download. We do not plan to design other versions of plexiglass inserts and meshes. We have designed only one model, what is compatible with most of the commercially available brain slice chambers worldwide. 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.

 

We can manufacture a special, circle-symmetric, plexiglass chamber if you need it (on the unity, list price). You should design it, and we will manufacture it according to your draft drawing. Certainly, our engineer will help you to design if you need it. There are many different kinds of chambers, heater plates, stages, and mechanical adaptors in the different labs. The new chamber designed by you must fit mechanically to your given environment. The fitting measure of the new chamber is the diameter of the hole, where you would like to put the chamber. The easiest way of design if you have the mechanical drawing of your original chamber. Please send us this drawing, and we will design the new chamber to be compatible with your original one.

 

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 plexiglass insert:

 

        Click on the picture to get it in full size

 

Plexiglass 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 plexiglass inserts chemically. Please take this aspect into account.

 

We offer the complete assembly "Plexiglass 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 plexiglass inserts is not sure, they are simply changed. The new plexiglass parts can be assembled together with the old, but disinfected mesh. Similarly, the mesh can also be changed any time.