A quantitative approach to the dielectric properties of the skin

The results of measurements using an open-ended coaxial probe of the audio/ radiofrequency dielectric properties of human skin in vivo, either dry or m oistened with physiological saline, are reported. Permittivity and conducti vity dispersion curves were parametrized by using a newly reported dispersi on function (Raicu V 1999 Dielectric properties of biological matter: model combining Debye-type and 'universal' responses Phys. Rev. E60 4677), and t he results obtained are discussed in the light of the recent advances in th is held. It is suggested that the coaxial probe reports on the properties o f the superficial layer, the stratum corneum, when the skin surface is dry, whilst the signal from deeper skin layers becomes dominant after wetting t he skin with conductive physiological saline.