Eco-Friendly Bioimpedance Muscle Phantom: PVA-Agar Hydrogel Mimicking Living Tissue at Low Frequencies.

In this study, we present the development of a muscle phantom using a hydrogel composed of polyvinyl alcohol (PVA), agar, graphite, and NaCl, cross-linked through freeze/thaw cycling. We compared the properties of the PVA hydrogel with those of a PVA-agar hydrogel filled with graphite and NaCl. To characterize and optimize the mixtures, samples with varying graphite concentrations were prepared, and their electrical properties were measured using bioelectrical impedance spectroscopy (BIS) over a low-frequency range (1 kHz-1 MHz).