Relaxation polarization model of SD rat tissues at frequency range 42Hz–5MHz

With the increasing recognition of electromagnetic radiation to human health and environment, research on the dielectric phenomenon and the explanation on polarization theory of biological tissues has become an important part of biological dielectric. Our recent study about low-frequency polarization characteristics of SD (Sprague & Dawley) rat tissues found that the polarization characteristic of tissues is consistent with CS (Curie-von Schweidler) polarization theory in α and β relaxation polarization frequency band. In this paper, a designed electrode system was used to test the dielectric parameters of typical SD rat tissues (liver, etc.) by LCR impedance analyzer in-vitro at room temperature. According to related Cole-Cole plot, polarization model of SD rat liver at this range is not a single Debye polarization, but an intricate model accompanied with multiple polarization processes where Debye and CS polarization theory have different proportions at this frequency range. Meanwhile, polarizations of other typical tissues (lung, kidney) are also in line with the theory of CS polarization. With the variation of the imaginary part and the dielectric modulus, the CS polarization model of SD rat in this frequency range was obtained, and the application value of CS polarization theory in the phenomenon of biological tissue polarization was verified. Therefore, at this frequency range, CS polarization model of the biological tissues can be used for further study on the biological dielectric polarization.