Bioimpedance for Glucose Monitoring: Electrode Configuration and Metabolic Variability in Experimental Studies

Abstract

The search for non-invasive methods to estimate blood glucose levels has driven research into bioimpedance based on Electrochemical Impedance Spectroscopy (EIS) [1,2]. Various studies have demonstrated correlations between glucose levels and the electrical properties of the skin measured through impedance [3]. To enhance accuracy, optimizing factors such as electrode geometry is essential. This work investigated the configuration of contiguous parallel plate electrodes through simulations and experimental measurements in skin analog materials (SAM) and human skin. Measurements on three healthy volunteers, combining impedance and glucometry, examined glucose absorption and its effects on skin resistance. The results revealed impedance changes reflecting metabolic alterations induced by glucose, consistent with previous studies. Continuous measurements over 2.5 hours showed a probable correlation between impedance and blood glucose levels, albeit with a delay due to tissue differences, highlighting the complexity of the skin's response to glucose.