Skin layers characterisation by fractional bioimpendace

Abstract

Bioelectro-mechanical properties of skin can be very valid data for analyzing fractal characteristics of skin structure. In this paper, bioelectrical impedance method and fractional calculus have been utilized for the characterization of the human skin. Our fractional model is the generalized continuous Cole - Cole model because it predicts structural - functional parameters as a lot of Cole-Cole complex relaxation times. It is shown, using the proposed model and experimental results, that these parameters depend on the fractional indexes as a degree of the fractional derivatives in interval [0, 1]. These relaxation time constants correspond to structural -functional characteristics of the skin. The integral approximation of continual Cole - Cole model was done from ten points corresponding to orderly connected known reduced Cole-Cole elements. It was experimentally observed that five reduced Cole - Cole elements had significant values of complex relaxation times. These results open a new window of skin layer interpretation and investigation based on water well ordered nanolayers in epidermis.