Study and Analysis of Electrode, Electrolyte and Skin Interface with Emphasis on Overall Magnitude of Impedance

Skin layer analysis is crucial for the diagnosis of skin problems and for tracking the outcome of treatment. The outermost layer of the skin is called the stratum corneum (SC). It is mainly composed of lipids and keratin. The visible layers of the epidermis renew and shed their cells. This study aims to investigate the skin-electrode interface and form factor design. It is necessary to analyze the skin-electrode interface under various circumstances. Analyzing the skin-electrode interface is required in various conditions, like biomedical signal acquisition and transdermal drug delivery (TDD). The complex structure of human skin can be simulated using an electrical equivalent circuit to find the frequency-dependent impedance of the skin. Researchers have made various efforts to identify and reduce the impedance magnitude during interface to get better biomedical signals. A few of the methods of reducing impedance during interface are reported in the literature as mechanical abrasive, chemical removal, and μneedle insertion methods. These methods and their effects are analyzed in detail in this work. This work provides a practical skin-electrode interface analysis, which will help develop a realistic model for future research and biomedical applications.