An exposure device (or an applicator) is a device for the application controlled electromagnetic field intensities to biological samples. While the purpose of most antenna designs is to send messages to remote distances with optimal efficiency, design of exposure devices for bioelectromagnetic experiments aims at applying fields with desired intensity and favorable distribution within a biological sample with high efficiency. Clinical Applicators used for therapy exposure apply fields onto the surface or into the body for diagnosis (e.g. skin cancer detection) or treatment (e.g. hyperthermia, tDCS, TMS).
In terms of Bio-electromagnetic research, exposure devices can be classified into those designed for tissue, cellular or molecular (solution) samples. From a technical view, exposure devices can be classified as operating in free space, or with guided waves, based on resonant structures, and near-field (usually in the low frequency). There are exposure designs that enable simultaneous monitoring of biological effects (e.g. microscopy), which is an advantage over offline exposure, i.e. observing biological effects subsequent to exposure.
Based on our experience there are a number of favorable criteria for a good laboratory exposure device:
- Realization of electric/magnetic fields with specific amplitude and polarization at frequencies of interest.
- Field homogeneity within the sample.
- Controlled field intensity within the sample
- Controlled temperature and temperature homogeneity within the sample
- High field intensity within the sample for low input power (high efficiency)
- User safety and necessary protection; stable performance against environmental changes and unforeseen circumstances (Proximity to metallic objects, power cord magnetic interference, etc.)
- Monitoring the applied field quantities during exposure.
1978- Using electrophoresis to apply a constant flow and to apply a uniform electric field onto cell monolayers in room conditions. Can simultaneously measure changes of cell layer conductivity.
1981- Using electrophoresis to apply a constant current flow and a uniform electric field to tissue in room conditions, together with perfusion.
1996- Using electrophoresis to apply a constant current flow and a uniform electric field to cell monolayers In the vicinity of 37°C water. Can simultaneously measure
changes of cell layer conductivity.
1996- As before, but with the use of Pasteur pipette at any time during field exposure to provide the material necessary for cell growth.
2001- As before, with cells placed in a chamber with a temperature of 37 ° C and observed by inverted microscope simultaneously during exposure.
2002- As before while cells placed within a chamber with carbon dioxide 5% and air of 37 ° C temperature. Sample simultaneously observed by inverted microscope and Capable of measuring changes of cell layer conductivity during exposure.
2005- Using electrophoresis to apply a constant flow and a uniform electric field onto cell monolayers. Humidity supplied by placing two wet wipes inside the chamber. Observed by inverted microscope simultaneously and capable of measuring changes of cell layer conductivity.
2007- As above, but with extra space for cell migration and addition of necessary measures for supplying solutions for cell growth and the elimination of waste. Temperature and Co2 are controlled by performing the Experiments within a standard incubator.
2014- Using electrophoresis to apply a constant flow and a uniform electric field onto cell monolayers. Experiments performed in the mini-incubator and Sample simultaneously observed by inverted microscope.