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bioRxiv · 10.1101/2022.08.16.504138

In-vivo Measurement of Radio Frequency Electric Fields in Mice Brain

Yaghmazadeh, O.·Schoenhardt, S.·Sarabandi, A.·Sabet, A.·Sabet, K.·Safari, F.·Alon, L.·Buzsaki, G.
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Abstract

With development of novel technologies, radio frequency (RF) energy exposure is expanding at various wavelengths and power levels. These developments necessitate updated approaches of RF measurements in complex environments, particularly in live biological tissue. In this study, we introduce a technique for direct in-vivo measurement of electric fields in living tissue. Proof of principle in-vivo electric field measurements were conducted in rodent brains using Bismuth Silicon Oxide (BSO) crystals exposed to varying levels of RF energy. Electric field measurements were calibrated and verified using in-vivo temperature measurements using optical temperature fibers alongside electromagnetic field simulations of a transverse electromagnetic (TEM) cell. SIGNIFICANCEAccurate dosimetry of the absorbed radio frequency (RF) electric fields (E-Fields) by the live tissue is the keystone of environmental health considerations for this type of ever-growing non-ionizing radiation energy. The complexity of biological tissue and technical difficulties have made direct measurement of E-fields in live tissue challenging leading to application of ex-vivo and in-silico approaches. Here, we present a novel method for in-vivo direct measurement of RF E-fields in anesthetized mice brain using electro-optic sensors.

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Yaghmazadeh, O., Schoenhardt, S., Sarabandi, A., Sabet, A., Sabet, K., Safari, F., Alon, L., Buzsaki, G.. 2022-08-16. In-vivo Measurement of Radio Frequency Electric Fields in Mice Brain. https://doi.org/10.1101/2022.08.16.504138

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